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Sample records for aircraft electrical systems

  1. Promising Electric Aircraft Drive Systems

    NASA Technical Reports Server (NTRS)

    Dudley, Michael R.

    2010-01-01

    An overview of electric aircraft propulsion technology performance thresholds for key power system components is presented. A weight comparison of electric drive systems with equivalent total delivered energy is made to help identify component performance requirements, and promising research and development opportunities.

  2. Power system characteristics for more electric aircraft

    NASA Technical Reports Server (NTRS)

    Hansen, Irving G.

    1993-01-01

    It should not be suprising that more electric aircraft must meet significantly more difficult electrical power system requirements than were considereed when today's power distribution systems were being developed. Electric power, no longer a secondary system, will become a critical element of the primary control system. Functional reliability requiirements will be extremely stringent and can only be met by controlling element redundancy within a distributed power system. Existing electrical systems were not developed to have both the power system and the control/sensing elements distributed and yet meet the requirements of lighting tolerance and high intensity radio frequency (HIRF). In addition, the operation of electric actuators involves high transient loading and reverse energy flows. Such phenomena were also not anticipated when power quality was specified for either 270 vdc or 400 Hertz ac power systems. This paper will expand upon the issues and discuss some of the technologies involved in their resolution.

  3. Aircraft Electric Secondary Power

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Technologies resulted to aircraft power systems and aircraft in which all secondary power is supplied electrically are discussed. A high-voltage dc power generating system for fighter aircraft, permanent magnet motors and generators for aircraft, lightweight transformers, and the installation of electric generators on turbine engines are among the topics discussed.

  4. Advanced electrical power system technology for the all electric aircraft

    NASA Technical Reports Server (NTRS)

    Finke, R. C.; Sundberg, G. R.

    1983-01-01

    The application of advanced electric power system technology to an all electric airplane results in an estimated reduction of the total takeoff gross weight of over 23,000 pounds for a large airplane. This will result in a 5 to 10 percent reduction in direct operating costs (DOC). Critical to this savings is the basic electrical power system component technology. These advanced electrical power components will provide a solid foundation for the materials, devices, circuits, and subsystems needed to satisfy the unique requirements of advanced all electric aircraft power systems. The program for the development of advanced electrical power component technology is described. The program is divided into five generic areas: semiconductor devices (transistors, thyristors, and diodes); conductors (materials and transmission lines); dielectrics; magnetic devices; and load management devices. Examples of progress in each of the five areas are discussed. Bipolar power transistors up to 1000 V at 100 A with a gain of 10 and a 0.5 microsec rise and fall time are presented. A class of semiconductor devices with a possibility of switching up to 100 kV is described. Solid state power controllers for load management at 120 to 1000 V and power levels to 25 kW were developed along with a 25 kW, 20 kHz transformer weighing only 3.2 kg.

  5. Advanced electrical power system technology for the all electric aircraft

    NASA Technical Reports Server (NTRS)

    Finke, R. C.; Sundberg, G. R.

    1983-01-01

    The application of advanced electric power system technology to an all electric airplane results in an estimated reduction of the total takeoff gross weight of over 23,000 pounds for a large airplane. This will result in a 5 to 10 percent reduction in direct operating costs (DOC). Critical to this savings is the basic electrical power system component technology. These advanced electrical power components will provide a solid foundation for the materials, devices, circuits, and subsystems needed to satisfy the unique requirements of advanced all electric aircraft power systems. The program for the development of advanced electrical power component technology is described. The program is divided into five generic areas: semiconductor devices (transistors, thyristors, and diodes); conductors (materials and transmission lines); dielectrics; magnetic devices; and load management devices. Examples of progress in each of the five areas are discussed. Bipolar power transistors up to 1000 V at 100 A with a gain of 10 and a 0.5 microsec rise and fall time are presented. A class of semiconductor devices with a possibility of switching up to 100 kV is described. Solid state power controllers for load management at 120 to 1000 V and power levels to 25 kW were developed along with a 25 kW, 20 kHz transformer weighing only 3.2 kg. Previously announced in STAR as N83-24764

  6. Aircraft Electric Propulsion Systems Applied Research at NASA

    NASA Technical Reports Server (NTRS)

    Clarke, Sean

    2015-01-01

    Researchers at NASA are investigating the potential for electric propulsion systems to revolutionize the design of aircraft from the small-scale general aviation sector to commuter and transport-class vehicles. Electric propulsion provides new degrees of design freedom that may enable opportunities for tightly coupled design and optimization of the propulsion system with the aircraft structure and control systems. This could lead to extraordinary reductions in ownership and operating costs, greenhouse gas emissions, and noise annoyance levels. We are building testbeds, high-fidelity aircraft simulations, and the first highly distributed electric inhabited flight test vehicle to begin to explore these opportunities.

  7. Aircraft Electric/Hybrid-Electric Power and Propulsion Workshop Perspective of the V/STOL Aircraft Systems Tech Committee

    NASA Technical Reports Server (NTRS)

    Hange, Craig E.

    2016-01-01

    This presentation will be given at the AIAA Electric Hybrid-Electric Power Propulsion Workshop on July 29, 2016. The workshop is being held so the AIAA can determine how it can support the introduction of electric aircraft into the aerospace industry. This presentation will address the needs of the community within the industry that advocates the use of powered-lift as important new technologies for future aircraft and air transportation systems. As the current chairman of the VSTOL Aircraft Systems Technical Committee, I will be presenting generalized descriptions of the past research in developing powered-lift and generalized observations on how electric and hybrid-electric propulsion may provide advances in the powered-lift field.

  8. Systems Analysis Initiated for All-Electric Aircraft Propulsion

    NASA Technical Reports Server (NTRS)

    Kohout, Lisa L.

    2003-01-01

    A multidisciplinary effort is underway at the NASA Glenn Research Center to develop concepts for revolutionary, nontraditional fuel cell power and propulsion systems for aircraft applications. There is a growing interest in the use of fuel cells as a power source for electric propulsion as well as an auxiliary power unit to substantially reduce or eliminate environmentally harmful emissions. A systems analysis effort was initiated to assess potential concepts in an effort to identify those configurations with the highest payoff potential. Among the technologies under consideration are advanced proton exchange membrane (PEM) and solid oxide fuel cells, alternative fuels and fuel processing, and fuel storage. Prior to this effort, the majority of fuel cell analysis done at Glenn was done for space applications. Because of this, a new suite of models was developed. These models include the hydrogen-air PEM fuel cell; internal reforming solid oxide fuel cell; balance-of-plant components (compressor, humidifier, separator, and heat exchangers); compressed gas, cryogenic, and liquid fuel storage tanks; and gas turbine/generator models for hybrid system applications. Initial mass, volume, and performance estimates of a variety of PEM systems operating on hydrogen and reformate have been completed for a baseline general aviation aircraft. Solid oxide/turbine hybrid systems are being analyzed. In conjunction with the analysis efforts, a joint effort has been initiated with Glenn s Computer Services Division to integrate fuel cell stack and component models with the visualization environment that supports the GRUVE lab, Glenn s virtual reality facility. The objective of this work is to provide an environment to assist engineers in the integration of fuel cell propulsion systems into aircraft and provide a better understanding of the interaction between system components and the resulting effect on the overall design and performance of the aircraft. Initially, three

  9. Systems Analysis Developed for All-Electric Aircraft Propulsion

    NASA Technical Reports Server (NTRS)

    Kohout, Lisa L.

    2004-01-01

    There is a growing interest in the use of fuel cells as a power source for all-electric aircraft propulsion as a means to substantially reduce or eliminate environmentally harmful emissions. Among the technologies under consideration for these concepts are advanced proton exchange membrane (PEM) and solid oxide fuel cells (SOFCs), alternative fuels and fuel processing, and fuel storage. A multidisciplinary effort is underway at the NASA Glenn Research Center to develop and evaluate concepts for revolutionary, nontraditional fuel cell power and propulsion systems for aircraft applications. As part of this effort, system studies are being conducted to identify concepts with high payoff potential and associated technology areas for further development. To support this effort, a suite of component models was developed to estimate the mass, volume, and performance for a given system architecture. These models include a hydrogen-air PEM fuel cell; an SOFC; balance-of-plant components (compressor, humidifier, separator, and heat exchangers); compressed gas, cryogenic, and liquid fuel storage tanks; and gas turbine/generator models for hybrid system applications. First-order feasibility studies were completed for an all-electric personal air vehicle utilizing a fuel-cell-powered propulsion system. A representative aircraft with an internal combustion engine was chosen as a baseline to provide key parameters to the study, including engine power and subsystem mass, fuel storage volume and mass, and aircraft range. The engine, fuel tank, and associated ancillaries were then replaced with a fuel cell subsystem. Various configurations were considered including a PEM fuel cell with liquid hydrogen storage, a direct methanol PEM fuel cell, and a direct internal reforming SOFC/turbine hybrid system using liquid methane fuel. Each configuration was compared with the baseline case on a mass and range basis.

  10. Systems study for an Integrated Digital-Electric Aircraft (IDEA)

    NASA Technical Reports Server (NTRS)

    Tagge, G. E.; Irish, L. A.; Bailey, A. R.

    1985-01-01

    The results of the Integrated Digital/Electric Aircraft (IDEA) Study are presented. Airplanes with advanced systems were, defined and evaluated, as a means of identifying potential high payoff research tasks. A baseline airplane was defined for comparison, typical of a 1990's airplane with advanced active controls, propulsion, aerodynamics, and structures technology. Trade studies led to definition of an IDEA airplane, with extensive digital systems and electric secondary power distribution. This airplane showed an improvement of 3% in fuel use and 1.8% in DOC relative to the baseline configuration. An alternate configuration, an advanced technology turboprop, was also evaluated, with greater improvement supported by digital electric systems. Recommended research programs were defined for high risk, high payoff areas appropriate for implementation under NASA leadership.

  11. Electrical Thermometers for Aircraft

    NASA Technical Reports Server (NTRS)

    Peterson, John B; Womack, S H J

    1937-01-01

    Electrical thermometers commonly used on aircraft are the thermoelectric type for measuring engine-cylinder temperatures, the resistance type for measuring air temperatures, and the superheat meters of thermoelectric and resistance types for use on airships. These instruments are described and their advantages and disadvantages enumerated. Methods of testing these instruments and the performance to be expected from each are discussed. The field testing of engine-cylinder thermometers is treated in detail.

  12. Influence of the energy management on the sizing of Electrical Energy Storage Systems in an aircraft

    NASA Astrophysics Data System (ADS)

    Devillers, Nathalie; Péra, Marie-Cécile; Bienaimé, Daniel; Grojo, Marie-Laure

    2014-12-01

    In an aircraft, Electrical Energy Storage Systems (EESS) are used as support to other sources in few mission phases in order to ensure the energy availability. They are also used as electrical smoothing devices in order to guarantee the required levels of reliability, stability and quality for an embedded electrical network. This paper deals with the association of two EESS: supercapacitors and secondary battery, which exhibit complementary properties. In this paper, a sizing method for both EESS is developed by taking into account their hybridization and their characteristics (such as capacity or depth-of-discharge) so as to minimize the global storage system weight. Moreover, an energy management based on a frequency approach is implemented to dispatch the power between all the sources. The influence of this management on the sizing is studied. Indeed the cut-off frequency of the low-pass filter is used as a setting parameter of the sizing algorithm. Finally, the sizing validity is assessed and discussed according to temperature constraints. Although battery performances are reduced at low temperature, the sizing determined with the algorithm at 20 °C is still valid on all the temperature range thanks to an adaptation of the energy management parameter.

  13. Integrated digital/electric aircraft concepts study

    NASA Technical Reports Server (NTRS)

    Cronin, M. J.; Hays, A. P.; Green, F. B.; Radovcich, N. A.; Helsley, C. W.; Rutchik, W. L.

    1985-01-01

    The integrated digital/electrical aircraft (IDEA) is an aircraft concept which employs all electric secondary power systems and advanced digital flight control systems. After trade analysis, preferred systems were applied to the baseline configuration. An additional configuration, the alternate IDEA, was also considered. For this concept the design ground rules were relaxed in order to quantify additional synergistic benefits. It was proposed that an IDEA configuration and technical risks associated with the IDEA systems concepts be defined and the research and development required activities to reduce these risks be identified. The selected subsystems include: power generation, power distribution, actuators, environmental control system and flight controls systems. When the aircraft was resized, block fuel was predicted to decrease by 11.3 percent, with 7.9 percent decrease in direct operating cost. The alternate IDEA shows a further 3.4 percent reduction in block fuel and 3.1 percent reduction in direct operating cost.

  14. Airvolt Aircraft Electric Propulsion Test Stand

    NASA Technical Reports Server (NTRS)

    Samuel, Aamod; Lin, Yohan

    2015-01-01

    Development of an electric propulsion test stand that collects high-fidelity data of motor, inverter, and battery system efficiencies; thermal dynamics; and acoustics independent of manufacturer reported values will improve understanding of electric propulsion systems to be used in future aircraft. A buildup approach to this development reveals new areas of research and best practices in testing, and attempts to establish a standard for testing these systems.

  15. Energy Conversion and Storage Requirements for Hybrid Electric Aircraft

    NASA Technical Reports Server (NTRS)

    Misra, Ajay

    2016-01-01

    Among various options for reducing greenhouse gases in future large commercial aircraft, hybrid electric option holds significant promise. In the hybrid electric aircraft concept, gas turbine engine is used in combination with an energy storage system to drive the fan that propels the aircraft, with gas turbine engine being used for certain segments of the flight cycle and energy storage system being used for other segments. The paper will provide an overview of various energy conversion and storage options for hybrid electric aircraft. Such options may include fuel cells, batteries, super capacitors, multifunctional structures with energy storage capability, thermoelectric, thermionic or a combination of any of these options. The energy conversion and storage requirements for hybrid electric aircraft will be presented. The role of materials in energy conversion and storage systems for hybrid electric aircraft will be discussed.

  16. Unmanned aircraft systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Unmanned platforms have become increasingly more common in recent years for acquiring remotely sensed data. These aircraft are referred to as Unmanned Airborne Vehicles (UAV), Remotely Piloted Aircraft (RPA), Remotely Piloted Vehicles (RPV), or Unmanned Aircraft Systems (UAS), the official term used...

  17. Projected Demand and Potential Impacts to the National Airspace System of Autonomous, Electric, On-Demand Small Aircraft

    NASA Technical Reports Server (NTRS)

    Smith, Jeremy C.; Viken, Jeffrey K.; Guerreiro, Nelson M.; Dollyhigh, Samuel M.; Fenbert, James W.; Hartman, Christopher L.; Kwa, Teck-Seng; Moore, Mark D.

    2012-01-01

    Electric propulsion and autonomy are technology frontiers that offer tremendous potential to achieve low operating costs for small-aircraft. Such technologies enable simple and safe to operate vehicles that could dramatically improve regional transportation accessibility and speed through point-to-point operations. This analysis develops an understanding of the potential traffic volume and National Airspace System (NAS) capacity for small on-demand aircraft operations. Future demand projections use the Transportation Systems Analysis Model (TSAM), a tool suite developed by NASA and the Transportation Laboratory of Virginia Polytechnic Institute. Demand projections from TSAM contain the mode of travel, number of trips and geographic distribution of trips. For this study, the mode of travel can be commercial aircraft, automobile and on-demand aircraft. NASA's Airspace Concept Evaluation System (ACES) is used to assess NAS impact. This simulation takes a schedule that includes all flights: commercial passenger and cargo; conventional General Aviation and on-demand small aircraft, and operates them in the simulated NAS. The results of this analysis projects very large trip numbers for an on-demand air transportation system competitive with automobiles in cost per passenger mile. The significance is this type of air transportation can enhance mobility for communities that currently lack access to commercial air transportation. Another significant finding is that the large numbers of operations can have an impact on the current NAS infrastructure used by commercial airlines and cargo operators, even if on-demand traffic does not use the 28 airports in the Continental U.S. designated as large hubs by the FAA. Some smaller airports will experience greater demand than their current capacity allows and will require upgrading. In addition, in future years as demand grows and vehicle performance improves other non-conventional facilities such as short runways incorporated into

  18. Developing Large-Scale Bayesian Networks by Composition: Fault Diagnosis of Electrical Power Systems in Aircraft and Spacecraft

    NASA Technical Reports Server (NTRS)

    Mengshoel, Ole Jakob; Poll, Scott; Kurtoglu, Tolga

    2009-01-01

    In this paper, we investigate the use of Bayesian networks to construct large-scale diagnostic systems. In particular, we consider the development of large-scale Bayesian networks by composition. This compositional approach reflects how (often redundant) subsystems are architected to form systems such as electrical power systems. We develop high-level specifications, Bayesian networks, clique trees, and arithmetic circuits representing 24 different electrical power systems. The largest among these 24 Bayesian networks contains over 1,000 random variables. Another BN represents the real-world electrical power system ADAPT, which is representative of electrical power systems deployed in aerospace vehicles. In addition to demonstrating the scalability of the compositional approach, we briefly report on experimental results from the diagnostic competition DXC, where the ProADAPT team, using techniques discussed here, obtained the highest scores in both Tier 1 (among 9 international competitors) and Tier 2 (among 6 international competitors) of the industrial track. While we consider diagnosis of power systems specifically, we believe this work is relevant to other system health management problems, in particular in dependable systems such as aircraft and spacecraft. (See CASI ID 20100021910 for supplemental data disk.)

  19. Aircraft Photovoltaic Power-Generating System.

    NASA Astrophysics Data System (ADS)

    Doellner, Oscar Leonard

    Photovoltaic cells, appropriately cooled and operating in the combustion-created high radiant-intensity environment of gas-turbine and jet engines, may replace the conventional (gearbox-driven) electrical power generators aboard jet aircraft. This study projects significant improvements not only in aircraft electrical power-generating-system performance, but also in overall aircraft performance. Jet -engine design modifications incorporating this concept not only save weight (and thus fuel), but are--in themselves --favorable to jet-engine performance. The dissertation concentrates on operational, constructional, structural, thermal, optical, radiometrical, thin-film, and solid-state theoretical aspects of the overall project. This new electrical power-generating system offers solid-state reliability with electrical power-output capability comparable to that of existing aircraft electromechanical power-generating systems (alternators and generators). In addition to improvements in aircraft performance, significant aircraft fuel- and weight-saving advantages are projected.

  20. Advanced secondary power system for transport aircraft

    NASA Technical Reports Server (NTRS)

    Hoffman, A. C.; Hansen, I. G.; Beach, R. F.; Plencner, R. M.; Dengler, R. P.; Jefferies, K. S.; Frye, R. J.

    1985-01-01

    A concept for an advanced aircraft power system was identified that uses 20-kHz, 440-V, sin-wave power distribution. This system was integrated with an electrically powered flight control system and with other aircraft systems requiring secondary power. The resulting all-electric secondary power configuration reduced the empty weight of a modern 200-passenger, twin-engine transport by 10 percent and the mission fuel by 9 percent.

  1. Comparison of Mars Aircraft Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Colozza, Anthony J.

    2003-01-01

    The propulsion system is a critical aspect of the performance and feasibility of a Mars aircraft. Propulsion system mass and performance greatly influence the aircraft s design and mission capabilities. Various propulsion systems were analyzed to estimate the system mass necessary for producing 35N of thrust within the Mars environment. Three main categories of propulsion systems were considered: electric systems, combustion engine systems and rocket systems. Also, the system masses were compared for mission durations of 1, 2, and 4 h.

  2. A new direction in energy conversion - The all-electric aircraft

    NASA Technical Reports Server (NTRS)

    Spitzer, C. R.

    1985-01-01

    This paper reviews recent studies of all-electric aircraft that use electric-only secondary power and flight critical fly-by-wire flight controls, and brings to the attention of the power system designer the intrinsic advantages of such aircraft. The all-electric aircraft is made possible by the development of rare earth magnet materials and fault tolerant systems technologies. Recent studies have shown all-electric aircraft to be more efficient than conventional designs and offer substantial operating costs reductions. Compared to present aircraft, an all-electric transport can save at least 10 percent in fuel burn. The cornerstone of an all-electric aircraft is the electric secondary power system. This paper reviews the major features of flight critical electric secondary power systems. Research required to lay the foundation for an all-electric aircraft is briefly discussed.

  3. Material Challenges and Opportunities for Commercial Electric Aircraft

    NASA Technical Reports Server (NTRS)

    Misra, Ajay

    2014-01-01

    Significant reduction in carbon dioxide emission for future air transportation system will require adoption of electric propulsion system and more electric architectures. Various options for aircraft electric propulsion include hybrid electric, turboelectric, and full electric system. Realization of electric propulsion system for commercial aircraft applications will require significant increases in power density of electric motors and energy density of energy storage system, such as the batteries and fuel cells. In addition, transmission of MW of power in the aircraft will require high voltage power transmission system to reduce the weight of the power transmission system. Finally, there will be significant thermal management challenges. Significant advances in material technologies will be required to meet these challenges. Technologies of interest include materials with higher electrical conductivity than Cu, high thermal conductivity materials, and lightweight electrically insulating materials with high breakdown voltage, high temperature magnets, advanced battery and fuel cell materials, and multifunctional materials. The presentation will include various challenges for commercial electric aircraft and provide an overview of material improvements that will be required to meet these challenges.

  4. Integrated topology for an aircraft electric power distribution system using MATLAB and ILP optimization technique and its implementation

    NASA Astrophysics Data System (ADS)

    Madhikar, Pratik Ravindra

    The most important and crucial design feature while designing an Aircraft Electric Power Distribution System (EPDS) is reliability. In EPDS, the distribution of power is from top level generators to bottom level loads through various sensors, actuators and rectifiers with the help of AC & DC buses and control switches. As the demands of the consumer is never ending and the safety is utmost important, there is an increase in loads and as a result increase in power management. Therefore, the design of an EPDS should be optimized to have maximum efficiency. This thesis discusses an integrated tool that is based on a Need Based Design method and Fault Tree Analysis (FTA) to achieve the optimum design of an EPDS to provide maximum reliability in terms of continuous connectivity, power management and minimum cost. If an EPDS is formulated as an optimization problem then it can be solved with the help of connectivity, cost and power constraints by using a linear solver to get the desired output of maximum reliability at minimum cost. Furthermore, the thesis also discusses the viability and implementation of the resulted topology on typical large aircraft specifications.

  5. Aircraft noise synthesis system

    NASA Technical Reports Server (NTRS)

    Mccurdy, David A.; Grandle, Robert E.

    1987-01-01

    A second-generation Aircraft Noise Synthesis System has been developed to provide test stimuli for studies of community annoyance to aircraft flyover noise. The computer-based system generates realistic, time-varying, audio simulations of aircraft flyover noise at a specified observer location on the ground. The synthesis takes into account the time-varying aircraft position relative to the observer; specified reference spectra consisting of broadband, narrowband, and pure-tone components; directivity patterns; Doppler shift; atmospheric effects; and ground effects. These parameters can be specified and controlled in such a way as to generate stimuli in which certain noise characteristics, such as duration or tonal content, are independently varied, while the remaining characteristics, such as broadband content, are held constant. The system can also generate simulations of the predicted noise characteristics of future aircraft. A description of the synthesis system and a discussion of the algorithms and methods used to generate the simulations are provided. An appendix describing the input data and providing user instructions is also included.

  6. Aircraft Operations Classification System

    NASA Technical Reports Server (NTRS)

    Harlow, Charles; Zhu, Weihong

    2001-01-01

    Accurate data is important in the aviation planning process. In this project we consider systems for measuring aircraft activity at airports. This would include determining the type of aircraft such as jet, helicopter, single engine, and multiengine propeller. Some of the issues involved in deploying technologies for monitoring aircraft operations are cost, reliability, and accuracy. In addition, the system must be field portable and acceptable at airports. A comparison of technologies was conducted and it was decided that an aircraft monitoring system should be based upon acoustic technology. A multimedia relational database was established for the study. The information contained in the database consists of airport information, runway information, acoustic records, photographic records, a description of the event (takeoff, landing), aircraft type, and environmental information. We extracted features from the time signal and the frequency content of the signal. A multi-layer feed-forward neural network was chosen as the classifier. Training and testing results were obtained. We were able to obtain classification results of over 90 percent for training and testing for takeoff events.

  7. Aircraft Fuel Cell Power Systems

    NASA Technical Reports Server (NTRS)

    Needham, Robert

    2004-01-01

    In recent years, fuel cells have been explored for use in aircraft. While the weight and size of fuel cells allows only the smallest of aircraft to use fuel cells for their primary engines, fuel cells have showed promise for use as auxiliary power units (APUs), which power aircraft accessories and serve as an electrical backup in case of an engine failure. Fuel cell MUS are both more efficient and emit fewer pollutants. However, sea-level fuel cells need modifications to be properly used in aircraft applications. At high altitudes, the ambient air has a much lower pressure than at sea level, which makes it much more difficult to get air into the fuel cell to react and produce electricity. Compressors can be used to pressurize the air, but this leads to added weight, volume, and power usage, all of which are undesirable things. Another problem is that fuel cells require hydrogen to create electricity, and ever since the Hindenburg burst into flames, aircraft carrying large quantities of hydrogen have not been in high demand. However, jet fuel is a hydrocarbon, so it is possible to reform it into hydrogen. Since jet fuel is already used to power conventional APUs, it is very convenient to use this to generate the hydrogen for fuel-cell-based APUs. Fuel cells also tend to get large and heavy when used for applications that require a large amount of power. Reducing the size and weight becomes especially beneficial when it comes to fuel cells for aircraft. My goal this summer is to work on several aspects of Aircraft Fuel Cell Power System project. My first goal is to perform checks on a newly built injector rig designed to test different catalysts to determine the best setup for reforming Jet-A fuel into hydrogen. These checks include testing various thermocouples, transmitters, and transducers, as well making sure that the rig was actually built to the design specifications. These checks will help to ensure that the rig will operate properly and give correct results

  8. Power Requirements Determined for High-Power-Density Electric Motors for Electric Aircraft Propulsion

    NASA Technical Reports Server (NTRS)

    Johnson, Dexter; Brown, Gerald V.

    2005-01-01

    Future advanced aircraft fueled by hydrogen are being developed to use electric drive systems instead of gas turbine engines for propulsion. Current conventional electric motor power densities cannot match those of today s gas turbine aircraft engines. However, if significant technological advances could be made in high-power-density motor development, the benefits of an electric propulsion system, such as the reduction of harmful emissions, could be realized.

  9. The all-electric aircraft - In your future?

    NASA Technical Reports Server (NTRS)

    Spitzer, Cary R.

    1984-01-01

    Recent developments in all-electric aircraft technology are reviewed with particular attention given to models with a digital fly-by-wire quadraplex control systems and experimental mechanical actuators. It is shown that all-electric technologies can eliminate many traditional design constraints and open up enormous range of design possibilities.

  10. Aircraft photovoltaic power-generating system

    NASA Astrophysics Data System (ADS)

    Doellner, Oscar Leonard

    Photovoltaic cells, appropriately cooled and operating in the combustion-created high radiant-intensity environment of gas-turbine and jet engines, may replace the conventional (gearbox-driven) electrical power generators aboard jet aircraft. This study projects significant improvements not only in aircraft electrical power-generating-system performance, but also in overall aircraft performance. Jet-engine design modifications incorporating this concept not only save weight (and thus fuel), but are - in themselves - favorable to jet-engine performance. The dissertation concentrates on operational, constructional, structural, thermal, optical, radiometrical, thin-film, and solid-state theoretical aspects of the overall project.

  11. Evaluation of all-electric secondary power for transport aircraft

    NASA Technical Reports Server (NTRS)

    Murray, W. E.; Feiner, L. J.; Flores, R. R.

    1992-01-01

    This report covers a study by Douglas Aircraft Company (DAC) of electrical power systems for advanced transport aircraft based upon an all-electric design concept. The concept would eliminate distributed hydraulic and pneumatic secondary power systems, and feature an expanded secondary electrical power system redesigned to supply power to the loads customarily supplied by hydraulic or pneumatic power. The initial study was based on an advanced 20-kHz electrical power transmission and distribution system, using a system architecture supplied by NASA-Lewis Research Center for twin-engine aircraft with many advanced power conversion concepts. NASA-LeRC later requested DAC to refocus the study on 400-Hz secondary power distribution. Subsequent work was based on a three-engine MD-11 aircraft, selected by DAC as a baseline system design that would provide data for the comparative cost/benefit analysis. The study concluded that the 20-kHz concept produced many expected benefits, and that the all-electric trijet weight savings on hardware redesign would be 2,304 pounds plus a 2.1-percent fuel reduction and resized for a total weight reduction of 11,000 pounds. Cost reductions for a fleet of 800 aircraft in a 15-year production program were estimated at $76.71 million for RDT&E; $2.74 million per aircrat for production; $9.84 million for nonrecurring expenses; $120,000 per aircraft for product support; and $300,000 per aircraft per year for operating and maintenance costs, giving a present value of $1.914 billion saved or a future value of $10.496 billion saved.

  12. Evaluation of all-electric secondary power for transport aircraft

    NASA Astrophysics Data System (ADS)

    Murray, W. E.; Feiner, L. J.; Flores, R. R.

    1992-01-01

    This report covers a study by Douglas Aircraft Company (DAC) of electrical power systems for advanced transport aircraft based upon an all-electric design concept. The concept would eliminate distributed hydraulic and pneumatic secondary power systems, and feature an expanded secondary electrical power system redesigned to supply power to the loads customarily supplied by hydraulic or pneumatic power. The initial study was based on an advanced 20-kHz electrical power transmission and distribution system, using a system architecture supplied by NASA-Lewis Research Center for twin-engine aircraft with many advanced power conversion concepts. NASA-LeRC later requested DAC to refocus the study on 400-Hz secondary power distribution. Subsequent work was based on a three-engine MD-11 aircraft, selected by DAC as a baseline system design that would provide data for the comparative cost/benefit analysis. The study concluded that the 20-kHz concept produced many expected benefits, and that the all-electric trijet weight savings on hardware redesign would be 2,304 pounds plus a 2.1-percent fuel reduction and resized for a total weight reduction of 11,000 pounds. Cost reductions for a fleet of 800 aircraft in a 15-year production program were estimated at $76.71 million for RDT&E $2.74 million per aircrat for production; $9.84 million for nonrecurring expenses; $120,000 per aircraft for product support; and $300,000 per aircraft per year for operating and maintenance costs, giving a present value of $1.914 billion saved or a future value of $10.496 billion saved.

  13. Turboprop cargo aircraft systems study

    NASA Technical Reports Server (NTRS)

    Muehlbauer, J. C.; Hewell, J. G., Jr.; Lindenbaum, S. P.; Randall, C. C.; Searle, N.; Stone, R. G., Jr.

    1981-01-01

    The effects of using advanced turboprop propulsion systems to reduce the fuel consumption and direct operating costs of cargo aircraft were studied, and the impact of these systems on aircraft noise and noise prints around a terminal area was determined. Parametric variations of aircraft and propeller characteristics were investigated to determine their effects on noiseprint areas, fuel consumption, and direct operating costs. From these results, three aircraft designs were selected and subjected to design refinements and sensitivity analyses. Three competitive turbofan aircraft were also defined from parametric studies to provide a basis for comparing the two types of propulsion.

  14. Aircraft landing gear systems

    NASA Technical Reports Server (NTRS)

    Tanner, John A. (Editor)

    1990-01-01

    Topics presented include the laboratory simulation of landing gear pitch-plane dynamics, a summary of recent aircraft/ground vehicle friction measurement tests, some recent aircraft tire thermal studies, and an evaluation of critical speeds in high-speed aircraft. Also presented are a review of NASA antiskid braking research, titanium matrix composite landing gear development, the current methods and perspective of aircraft flotation analysis, the flow rate and trajectory of water spray produced by an aircraft tire, and spin-up studies of the Space Shuttle Orbiter main gear tire.

  15. Misconceptions of Electric Propulsion Aircraft and Their Emergent Aviation Markets

    NASA Technical Reports Server (NTRS)

    Moore, Mark D.; Fredericks, Bill

    2014-01-01

    Over the past several years there have been aircraft conceptual design and system studies that have reached conflicting conclusions relating to the feasibility of full and hybrid electric aircraft. Some studies and propulsion discipline experts have claimed that battery technologies will need to improve by 10 to 20 times before electric aircraft can effectively compete with reciprocating or turbine engines. However, such studies have approached comparative assessments without understanding the compelling differences that electric propulsion offers, how these technologies will fundamentally alter the way propulsion integration is approached, or how these new technologies can not only compete but far exceed existing propulsion solutions in many ways at battery specific energy densities of only 400 watt hours per kilogram. Electric propulsion characteristics offer the opportunity to achieve 4 to 8 time improvements in energy costs with dramatically lower total operating costs, while dramatically improving efficiency, community noise, propulsion system reliability and safety through redundancy, as well as life cycle Green House Gas emissions. Integration of electric propulsion will involve far greater degrees of distribution than existing propulsion solutions due to their compact and scale-free nature to achieve multi-disciplinary coupling and synergistic integration with the aerodynamics, highlift system, acoustics, vehicle control, balance, and aeroelasticity. Appropriate metrics of comparison and differences in analysis/design tools are discussed while comparing electric propulsion to other disruptive technologies. For several initial applications, battery energy density is already sufficient for competitive products, and for many additional markets energy densities will likely be adequate within the next 7 years for vibrant introduction. Market evolution and early adopter markets are discussed, along with the investment areas that will fill technology gaps and

  16. Intelligent aircraft/airspace systems

    NASA Technical Reports Server (NTRS)

    Wangermann, John P.

    1995-01-01

    Projections of future air traffic predict at least a doubling of the number of revenue passenger miles flown by the year 2025. To meet this demand, an Intelligent Aircraft/Airspace System (IAAS) has been proposed. The IAAS operates on the basis of principled negotiation between intelligent agents. The aircraft/airspace system today consists of many agents, such as airlines, control facilities, and aircraft. All the agents are becoming increasingly capable as technology develops. These capabilities should be exploited to create an Intelligent Aircraft/Airspace System (IAAS) that would meet the predicted traffic levels of 2005.

  17. Aircraft Engine Systems

    NASA Technical Reports Server (NTRS)

    Veres, Joseph

    2001-01-01

    This report outlines the detailed simulation of Aircraft Turbofan Engine. The objectives were to develop a detailed flow model of a full turbofan engine that runs on parallel workstation clusters overnight and to develop an integrated system of codes for combustor design and analysis to enable significant reduction in design time and cost. The model will initially simulate the 3-D flow in the primary flow path including the flow and chemistry in the combustor, and ultimately result in a multidisciplinary model of the engine. The overnight 3-D simulation capability of the primary flow path in a complete engine will enable significant reduction in the design and development time of gas turbine engines. In addition, the NPSS (Numerical Propulsion System Simulation) multidisciplinary integration and analysis are discussed.

  18. SILHIL Replication of Electric Aircraft Powertrain Dynamics and Inner-Loop Control for V&V of System Health Management Routines

    NASA Technical Reports Server (NTRS)

    Bole, Brian; Teubert, Christopher Allen; Cuong Chi, Quach; Hogge, Edward; Vazquez, Sixto; Goebel, Kai; George, Vachtsevanos

    2013-01-01

    Software-in-the-loop and Hardware-in-the-loop testing of failure prognostics and decision making tools for aircraft systems will facilitate more comprehensive and cost-effective testing than what is practical to conduct with flight tests. A framework is described for the offline recreation of dynamic loads on simulated or physical aircraft powertrain components based on a real-time simulation of airframe dynamics running on a flight simulator, an inner-loop flight control policy executed by either an autopilot routine or a human pilot, and a supervisory fault management control policy. The creation of an offline framework for verifying and validating supervisory failure prognostics and decision making routines is described for the example of battery charge depletion failure scenarios onboard a prototype electric unmanned aerial vehicle.

  19. Design of a 4-seat, general aviation, electric aircraft

    NASA Astrophysics Data System (ADS)

    Rajagopalan, Arvindhakshan

    Range and payload of current electric aircraft is limited primarily due to low energy density of batteries. However, recent advances in battery technology promise storage of more than 1 kWh of energy per kilogram of weight in the near future. This kind of energy storage makes possible the design of an electric aircraft comparable to, if not better than existing state-of-the art general aviation aircraft powered by internal combustion engines. This thesis explores through parametric studies the effect of lift-to-drag ratio, flight speed, and cruise altitude on required thrust power and battery energy and presents the conceptual and preliminary design of a four-seat, general aviation electric aircraft with a takeoff weight of 1750 kg, a range of 800 km, and a cruise speed of 200 km/h. An innovative configuration design will take full advantage of the electric propulsion system, while a Lithium-Polymer battery and a DC brush less motor will provide the power. Advanced aerodynamics will explore the greatest possible extend of laminar flow on the fuselage, the wing, and the empennage surfaces to minimize drag, while advanced composite structures will provide the greatest possible savings on empty weight. The proposed design is intended to be certifiable under current FAR 23 requirements.

  20. Design and simulation of a fuel cell hybrid emergency power system for a more electric aircraft: Evaluation of energy management schemes

    NASA Astrophysics Data System (ADS)

    Njoya Motapon, Souleman

    As the aircraft industries are moving toward more electric aircraft (MEA), the electrical peak load seen by the main and emergency generators becomes higher than in conventional aircraft. Consequently, there is a major concern regarding the aircraft emergency system, which consists of a ram air turbine (RAT) or air driven generator (ADG), to fulfill the load demand during critical situations; particularly at low aircraft speed where the output power is very low. A potential solution under study by most aircraft manufacturers is to replace the air turbine by a fuel cell hybrid system, consisting of fuel cell combined with other high power density sources such as supercapacitors or lithium-ion batteries. To ensure the fuel cell hybrid system will be able to meet the load demand, it must be properly designed and an effective energy management strategy must be tested with real situations load profile. This work aims at designing a fuel cell emergency power system of a more electric aircraft and comparing different energy management schemes (EMS); with the goal to ensure the load demand is fully satisfied within the constraints of each energy source. The fuel cell hybrid system considered in this study consists of fuel cell, lithium-ion batteries and supercapacitors, along with associated DC-DC and DC-AC converters. The energy management schemes addressed are state-of-the-art, most commonly used energy management techniques in fuel cell vehicle applications and include: the state machine control strategy, the rule based fuzzy logic strategy, the classical PI control strategy, the frequency decoupling/fuzzy logic control strategy and the equivalent consumption minimization strategy (ECMS). Moreover, a new optimal scheme based on maximizing the instantaneous energy of batteries/supercapacitors, to improve the fuel economy is proposed. An off-line optimization based scheme is also developed to ascertain the validity of the proposed strategy in terms of fuel consumption

  1. Developing Large-Scale Bayesian Networks by Composition: Fault Diagnosis of Electrical Power Systems in Aircraft and Spacecraft

    NASA Technical Reports Server (NTRS)

    Mengshoel, Ole Jakob; Poll, Scott; Kurtoglu, Tolga

    2009-01-01

    This CD contains files that support the talk (see CASI ID 20100021404). There are 24 models that relate to the ADAPT system and 1 Excel worksheet. In the paper an investigation into the use of Bayesian networks to construct large-scale diagnostic systems is described. The high-level specifications, Bayesian networks, clique trees, and arithmetic circuits representing 24 different electrical power systems are described in the talk. The data in the CD are the models of the 24 different power systems.

  2. A Study of Aircraft Fire Hazards Related to Natural Electrical Phenomena

    NASA Technical Reports Server (NTRS)

    Kester, Frank L.; Gerstein, Melvin; Plumer, J. A.

    1960-01-01

    The problems of natural electrical phenomena as a fire hazard to aircraft are evaluated. Assessment of the hazard is made over the range of low level electrical discharges, such as static sparks, to high level discharges, such as lightning strikes to aircraft. In addition, some fundamental work is presented on the problem of flame propagation in aircraft fuel vent systems. This study consists of a laboratory investigation in five parts: (1) a study of the ignition energies and flame propagation rates of kerosene-air and JP-6-air foams, (2) a study of the rate of flame propagation of n-heptane, n-octane, n-nonane, and n-decane in aircraft vent ducts, (3) a study of the damage to aluminum, titanium, and stainless steel aircraft skin materials by lightning strikes, (4) a study of fuel ignition by lightning strikes to aircraft skins, and (5) a study of lightning induced flame propagation in an aircraft vent system.

  3. Conceptual design of hybrid-electric transport aircraft

    NASA Astrophysics Data System (ADS)

    Pornet, C.; Isikveren, A. T.

    2015-11-01

    The European Flightpath 2050 and corresponding Strategic Research and Innovation Agenda (SRIA) as well as the NASA Environmentally Responsible Aviation N+ series have elaborated aggressive emissions and external noise reduction targets according to chronological waypoints. In order to deliver ultra-low or even zero in-flight emissions levels, there exists an increasing amount of international research and development emphasis on electrification of the propulsion and power systems of aircraft. Since the late 1990s, a series of experimental and a host of burgeouning commercial activities for fixed-wing aviation have focused on glider, ultra-light and light-sport airplane, and this is proving to serve as a cornerstone for more ambitious transport aircraft design and integration technical approaches. The introduction of hybrid-electric technology has dramatically expanded the design space and the full-potential of these technologies will be drawn through synergetic, tightly-coupled morphological and systems integration emphasizing propulsion - as exemplified by the potential afforded by distributed propulsion solutions. With the aim of expanding upon the current repository of knowledge associated with hybrid-electric propulsion systems a quad-fan arranged narrow-body transport aircraft equipped with two advanced Geared-Turbofans (GTF) and two Electrical Fans (EF) in an under-wing podded installation is presented in this technical article. The assessment and implications of an increasing Degree-of-Hybridization for Useful Power (HP,USE) on the overall sizing, performance as well as flight technique optimization of fuel-battery hybrid-electric aircraft is addressed herein. The integrated performance of the concept was analyzed in terms of potential block fuel burn reduction and change in vehicular efficiency in comparison to a suitably projected conventional aircraft employing GTF-only propulsion targeting year 2035. Results showed that by increasing HP,USE, significant

  4. Aircraft control system

    NASA Technical Reports Server (NTRS)

    Lisoski, Derek L. (Inventor); Kendall, Greg T. (Inventor)

    2007-01-01

    A solar rechargeable, long-duration, span-loaded flying wing, having no fuselage or rudder. Having a two-hundred foot wingspan that mounts photovoltaic cells on most all of the wing's top surface, the aircraft uses only differential thrust of its eight propellers to turn, pitch and yaw. The wing is configured to deform under flight loads to position the propellers such that the control can be achieved. Each of five segments of the wing has one or more motors and photovoltaic arrays, and produces its own lift independent of the other segments, to avoid loading them. Five two-sided photovoltaic arrays, in all, are mounted on the wing, and receive photovoltaic energy both incident on top of the wing, and which is incident also from below, through a bottom, transparent surface.

  5. Integrated engine-generator concept for aircraft electric secondary power

    NASA Technical Reports Server (NTRS)

    Secunde, R. R.; Macosko, R. P.; Repas, D. S.

    1972-01-01

    The integrated engine-generator concept of locating an electric generator inside an aircraft turbojet or turbofan engine concentric with, and driven by, one of the main engine shafts is discussed. When properly rated, the generator can serve as an engine starter as well as a generator of electric power. The electric power conversion equipment and generator controls are conveniently located in the aircraft. Preliminary layouts of generators in a large engine together with their physical sizes and weights indicate that this concept is a technically feasible approach to aircraft secondary power.

  6. Cryogenic system options for a superconducting aircraft propulsion system

    NASA Astrophysics Data System (ADS)

    Berg, F.; Palmer, J.; Bertola, L.; Miller, Paul; Dodds, Graham

    2015-12-01

    There is a perceived need in the future for a move away from traditional aircraft designs in order to meet ambitious emissions and fuel burn targets. High temperature superconducting distributed propulsion may be an enabler for aircraft designs that have better propulsive efficiency and lower drag. There has been significant work considering the electrical systems required, but less on the cryogenics to enable it. This paper discusses some of the major choices to be faced in cryocooling for aircraft. The likely need for a disposable cryogen to reduce power demand is explained. A set of cryocooling methods are considered in a sensitivity study, which shows that the feasibility of the cryogenic system will depend strongly on the superconducting technology and the aircraft platform. It is argued that all three aspects must be researched and designed in close collaboration to reach a viable solution.

  7. Applications of advanced electric/electronic technology to conventional aircraft

    NASA Technical Reports Server (NTRS)

    Heimbold, R. L.

    1980-01-01

    The desirability of seven advanced technologies as applied to three commercial aircraft of 1985 to 1995 was investigated. Digital fly by wire, multiplexing, ring laser gyro, integrated avionics, all electric airplane, electric load management, and fiber optics were considered for 500 passenger, 50 passenger, and 30 passenger aircraft. The major figure of merit used was Net Value of Technology based on procurement and operating cost over the life of the aircraft. An existing computer program, ASSET, was used to resize the aircraft and evalute fuel usage and maintenance costs for each candidate configuration. Conclusions were that, for the 500 passenger aircraft, all candidates had a worthwhile payoff with the all electric airplane having a large payoff.

  8. Aircraft measurement of electric field - Self-calibration

    NASA Technical Reports Server (NTRS)

    Winn, W. P.

    1993-01-01

    Aircraft measurement of electric fields is difficult as the electrically conducting surface of the aircraft distorts the electric field. Calibration requires determining the relations between the undistorted electric field in the absence of the vehicle and the signals from electric field meters that sense the local distorted fields in their immediate vicinity. This paper describes a generalization of a calibration method which uses pitch and roll maneuvers. The technique determines both the calibration coefficients and the direction of the electric vector. The calibration of individual electric field meters and the elimination of the aircraft's self-charge are described. Linear combinations of field mill signals are examined and absolute calibration and error analysis are discussed. The calibration method was applied to data obtained during a flight near thunderstorms.

  9. NASA Electric Aircraft Test Bed (NEAT) Development Plan - Design, Fabrication, Installation

    NASA Technical Reports Server (NTRS)

    Dyson, Rodger W.

    2016-01-01

    As large airline companies compete to reduce emissions, fuel, noise, and maintenance costs, it is expected that more of their aircraft systems will shift from using turbofan propulsion, pneumatic bleed power, and hydraulic actuation, to instead using electrical motor propulsion, generator power, and electrical actuation. This requires new flight-weight and flight-efficient powertrain components, fault tolerant power management, and electromagnetic interference mitigation technologies. Moreover, initial studies indicate some combination of ambient and cryogenic thermal management and relatively high bus voltages when compared to state of practice will be required to achieve a net system benefit. Developing all these powertrain technologies within a realistic aircraft architectural geometry and under realistic operational conditions requires a unique electric aircraft testbed. This report will summarize existing testbed capabilities located in the U.S. and details the development of a unique complementary testbed that industry and government can utilize to further mature electric aircraft technologies.

  10. MTR BASEMENT. GENERAL ELECTRIC CONTROL CONSOLE FOR AIRCRAFT NUCLEAR PROPULSION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    MTR BASEMENT. GENERAL ELECTRIC CONTROL CONSOLE FOR AIRCRAFT NUCLEAR PROPULSION EXPERIMENT NO. 1. INL NEGATIVE NO. 6510. Unknown Photographer, 9/29/1959 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  11. Unmanned Aircraft Systems at NASA Dryden

    NASA Video Gallery

    NASA Dryden has a heritage of developmental and operational experience with unmanned aircraft systems. Work on Boeing's sub-scale X-36 Tailless Fighter Agility Research Aircraft, X-48 Blended Wing ...

  12. Small Aircraft Data Distribution System

    NASA Technical Reports Server (NTRS)

    Chazanoff, Seth L.; Dinardo, Steven J.

    2012-01-01

    The CARVE Small Aircraft Data Distribution System acquires the aircraft location and attitude data that is required by the various programs running on a distributed network. This system distributes the data it acquires to the data acquisition programs for inclusion in their data files. It uses UDP (User Datagram Protocol) to broadcast data over a LAN (Local Area Network) to any programs that might have a use for the data. The program is easily adaptable to acquire additional data and log that data to disk. The current version also drives displays using precision pitch and roll information to aid the pilot in maintaining a level-level attitude for radar/radiometer mapping beyond the degree available by flying visually or using a standard gyro-driven attitude indicator. The software is designed to acquire an array of data to help the mission manager make real-time decisions as to the effectiveness of the flight. This data is displayed for the mission manager and broadcast to the other experiments on the aircraft for inclusion in their data files. The program also drives real-time precision pitch and roll displays for the pilot and copilot to aid them in maintaining the desired attitude, when required, during data acquisition on mapping lines.

  13. Enabling Electric Propulsion for Flight - Hybrid Electric Aircraft Research at AFRC

    NASA Technical Reports Server (NTRS)

    Clarke, Sean; Lin, Yohan; Kloesel, Kurt; Ginn, Starr

    2014-01-01

    Advances in electric machine efficiency and energy storage capability are enabling a new alternative to traditional propulsion systems for aircraft. This has already begun with several small concept and demonstration vehicles, and NASA projects this technology will be essential to meet energy and emissions goals for commercial aviation in the next 30 years. In order to raise the Technology Readiness Level of electric propulsion systems, practical integration and performance challenges will need to be identified and studied in the near-term so that larger, more advanced electric propulsion system testbeds can be designed and built. Researchers at NASA Armstrong Flight Research Center are building up a suite of test articles for the development, integration, and validation of these systems in a real world environment.

  14. An aircraft sensor fault tolerant system

    NASA Technical Reports Server (NTRS)

    Caglayan, A. K.; Lancraft, R. E.

    1982-01-01

    The design of a sensor fault tolerant system which uses analytical redundancy for the Terminal Configured Vehicle (TCV) research aircraft in a Microwave Landing System (MLS) environment was studied. The fault tolerant system provides reliable estimates for aircraft position, velocity, and attitude in the presence of possible failures in navigation aid instruments and onboard sensors. The estimates, provided by the fault tolerant system, are used by the automated guidance and control system to land the aircraft along a prescribed path. Sensor failures are identified by utilizing the analytic relationship between the various sensor outputs arising from the aircraft equations of motion.

  15. Deicing System Protects General Aviation Aircraft

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Kelly Aerospace Thermal Systems LLC worked with researchers at Glenn Research Center on deicing technology with assistance from the Small Business Innovation Research (SBIR) program. Kelly Aerospace acquired Northcoast Technologies Ltd., a firm that had conducted work on a graphite foil heating element under a NASA SBIR contract and developed a lightweight, easy-to-install, reliable wing and tail deicing system. Kelly Aerospace engineers combined their experiences with those of the Northcoast engineers, leading to the certification and integration of a thermoelectric deicing system called Thermawing, a DC-powered air conditioner for single-engine aircraft called Thermacool, and high-output alternators to run them both. Thermawing, a reliable anti-icing and deicing system, allows pilots to safely fly through ice encounters and provides pilots of single-engine aircraft the heated wing technology usually reserved for larger, jet-powered craft. Thermacool, an innovative electric air conditioning system, uses a new compressor whose rotary pump design runs off an energy-efficient, brushless DC motor and allows pilots to use the air conditioner before the engine even starts

  16. Mission Analysis and Aircraft Sizing of a Hybrid-Electric Regional Aircraft

    NASA Technical Reports Server (NTRS)

    Antcliff, Kevin R.; Guynn, Mark D.; Marien, Ty V.; Wells, Douglas P.; Schneider, Steven J.; Tong, Michael T.

    2016-01-01

    The purpose of this study was to explore advanced airframe and propulsion technologies for a small regional transport aircraft concept (approximately 50 passengers), with the goal of creating a conceptual design that delivers significant cost and performance advantages over current aircraft in that class. In turn, this could encourage airlines to open up new markets, reestablish service at smaller airports, and increase mobility and connectivity for all passengers. To meet these study goals, hybrid-electric propulsion was analyzed as the primary enabling technology. The advanced regional aircraft is analyzed with four levels of electrification, 0 percent electric with 100 percent conventional, 25 percent electric with 75 percent conventional, 50 percent electric with 50 percent conventional, and 75 percent electric with 25 percent conventional for comparison purposes. Engine models were developed to represent projected future turboprop engine performance with advanced technology and estimates of the engine weights and flowpath dimensions were developed. A low-order multi-disciplinary optimization (MDO) environment was created that could capture the unique features of parallel hybrid-electric aircraft. It is determined that at the size and range of the advanced turboprop: The battery specific energy must be 750 watt-hours per kilogram or greater for the total energy to be less than for a conventional aircraft. A hybrid vehicle would likely not be economically feasible with a battery specific energy of 500 or 750 watt-hours per kilogram based on the higher gross weight, operating empty weight, and energy costs compared to a conventional turboprop. The battery specific energy would need to reach 1000 watt-hours per kilogram by 2030 to make the electrification of its propulsion an economically feasible option. A shorter range and/or an altered propulsion-airframe integration could provide more favorable results.

  17. Aircraft

    DOEpatents

    Hibbs, B.D.; Lissaman, P.B.S.; Morgan, W.R.; Radkey, R.L.

    1998-09-22

    This disclosure provides a solar rechargeable aircraft that is inexpensive to produce, is steerable, and can remain airborne almost indefinitely. The preferred aircraft is a span-loaded flying wing, having no fuselage or rudder. Travelling at relatively slow speeds, and having a two-hundred foot wingspan that mounts photovoltaic cells on most all of the wing`s top surface, the aircraft uses only differential thrust of its eight propellers to turn. Each of five sections of the wing has one or more engines and photovoltaic arrays, and produces its own lift independent of the other sections, to avoid loading them. Five two-sided photovoltaic arrays, in all, are mounted on the wing, and receive photovoltaic energy both incident on top of the wing, and which is incident also from below, through a bottom, transparent surface. The aircraft is capable of a top speed of about ninety miles per hour, which enables the aircraft to attain and can continuously maintain altitudes of up to sixty-five thousand feet. Regenerative fuel cells in the wing store excess electricity for use at night, such that the aircraft can sustain its elevation indefinitely. A main spar of the wing doubles as a pressure vessel that houses hydrogen and oxygen gases for use in the regenerative fuel cell. The aircraft has a wide variety of applications, which include weather monitoring and atmospheric testing, communications, surveillance, and other applications as well. 31 figs.

  18. Aircraft

    DOEpatents

    Hibbs, Bart D.; Lissaman, Peter B. S.; Morgan, Walter R.; Radkey, Robert L.

    1998-01-01

    This disclosure provides a solar rechargeable aircraft that is inexpensive to produce, is steerable, and can remain airborne almost indefinitely. The preferred aircraft is a span-loaded flying wing, having no fuselage or rudder. Travelling at relatively slow speeds, and having a two-hundred foot wingspan that mounts photovoltaic cells on most all of the wing's top surface, the aircraft uses only differential thrust of its eight propellers to turn. Each of five sections of the wing has one or more engines and photovoltaic arrays, and produces its own lift independent of the other sections, to avoid loading them. Five two-sided photovoltaic arrays, in all, are mounted on the wing, and receive photovoltaic energy both incident on top of the wing, and which is incident also from below, through a bottom, transparent surface. The aircraft is capable of a top speed of about ninety miles per hour, which enables the aircraft to attain and can continuously maintain altitudes of up to sixty-five thousand feet. Regenerative fuel cells in the wing store excess electricity for use at night, such that the aircraft can sustain its elevation indefinitely. A main spar of the wing doubles as a pressure vessel that houses hydrogen and oxygen gasses for use in the regenerative fuel cell. The aircraft has a wide variety of applications, which include weather monitoring and atmospheric testing, communications, surveillance, and other applications as well.

  19. Fireworthiness of transport aircraft interior systems

    NASA Technical Reports Server (NTRS)

    Parker, J. A.; Kourtides, D. A.

    1982-01-01

    The fire worthiness of air transport interiors was evaluated. The effect of interior systems on the survival of passengers and crew in an uncontrolled transport aircraft fire is addressed. Modification of aircraft interior subsystem components which provide improvements in aircraft fire safety are examined. Three specific subsystem components, interior panels, seats and windows, offer the most immediate and highest payoff by modifying interior materials of existing aircrafts. It is shown that the new materials modifications reduce the fire hazards because of significant reduction in their characteristic flame spread, heat release, and smoke and toxic gas emissions.

  20. Advanced U. S. military aircraft battery systems

    SciTech Connect

    Flake, R.A.; Eskra, M.D.

    1990-01-01

    While most USAF aircraft currently use vented Ni-Cd for dc electrical power and emergency power, as well as the powering of lights and instruments prior to engine starting, these batteries have high maintenance requirements, low reliability, and no built-in testing capability with which to check battery health prior to flight. The USAF Wright R D Center accordingly initiated its Advanced Maintenance-Free NiCd Battery System development program in 1986, in order to develop a sealed Ni-Cd battery which would remain maintenance-free over a period of three years. Attention is being given to a high power bipolar battery design in which there are no individual cell cases or cell interconnects.

  1. Propulsion system study for Small Transport Aircraft Technology (STAT)

    NASA Technical Reports Server (NTRS)

    Smith, C. E.; Hirschkron, R.; Warren, R. E.

    1981-01-01

    Propulsion system technologies applicable to the generation of commuter airline aircraft expected to enter service in the 1990's are identified and evaluated in terms of their impact on aircraft operating economics and fuel consumption. The most promising technologies in the areas of engine, propeller, gearbox, and nacelle design are recommended for future research. Each item under consideration is evaluated relative to a modern baseline engine, the General Electric CT7-5, in a current technology aircraft flying a fixed range and payload. The analysis is presented for two aircraft sizes (30 and 50 passenger), over a range of mission lengths (100 to 1100 km) and fuel costs ($264 to $396 per cu m).

  2. Fireworthiness of transport aircraft interior systems

    NASA Technical Reports Server (NTRS)

    Parker, J. A.; Kourtides, D. A.

    1981-01-01

    The key materials question is addressed concerning the effect of interior systems on the survival of passengers and crew in the case of an uncontrolled transport aircraft fire. Technical opportunities are examined which are available through the modification of aircraft interior subsystem components, modifications that may reasonably be expected to provide improvements in aircraft fire safety. Subsystem components discussed are interior panels, seats, and windows. By virtue of their role in real fire situations and as indicated by the results of large scale simulation tests, these components appear to offer the most immediate and highest payoff possible by modifying interior materials of existing aircraft. These modifications have the potential of reducing the rate of fire growth, with a consequent reduction of heat, toxic gas, and smoke emission throughout the habitable interior of an aircraft, whatever the initial source of the fire.

  3. Aircraft system modeling error and control error

    NASA Technical Reports Server (NTRS)

    Kulkarni, Nilesh V. (Inventor); Kaneshige, John T. (Inventor); Krishnakumar, Kalmanje S. (Inventor); Burken, John J. (Inventor)

    2012-01-01

    A method for modeling error-driven adaptive control of an aircraft. Normal aircraft plant dynamics is modeled, using an original plant description in which a controller responds to a tracking error e(k) to drive the component to a normal reference value according to an asymptote curve. Where the system senses that (1) at least one aircraft plant component is experiencing an excursion and (2) the return of this component value toward its reference value is not proceeding according to the expected controller characteristics, neural network (NN) modeling of aircraft plant operation may be changed. However, if (1) is satisfied but the error component is returning toward its reference value according to expected controller characteristics, the NN will continue to model operation of the aircraft plant according to an original description.

  4. Lightweight, Efficient Power Converters for Advanced Turboelectric Aircraft Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Hennessy, Michael J.

    2014-01-01

    NASA is investigating advanced turboelectric aircraft propulsion systems that use superconducting motors to drive multiple distributed turbofans. Conventional electric motors are too large and heavy to be practical for this application; therefore, superconducting motors are required. In order to improve aircraft maneuverability, variable-speed power converters are required to throttle power to the turbofans. The low operating temperature and the need for lightweight components that place a minimum of additional heat load on the refrigeration system open the possibility of incorporating extremely efficient cryogenic power conversion technology. This Phase II project is developing critical components required to meet these goals.

  5. Multidisciplinary Techniques and Novel Aircraft Control Systems

    NASA Technical Reports Server (NTRS)

    Padula, Sharon L.; Rogers, James L.; Raney, David L.

    2000-01-01

    The Aircraft Morphing Program at NASA Langley Research Center explores opportunities to improve airframe designs with smart technologies. Two elements of this basic research program are multidisciplinary design optimization (MDO) and advanced flow control. This paper describes examples where MDO techniques such as sensitivity analysis, automatic differentiation, and genetic algorithms contribute to the design of novel control systems. In the test case, the design and use of distributed shapechange devices to provide low-rate maneuvering capability for a tailless aircraft is considered. The ability of MDO to add value to control system development is illustrated using results from several years of research funded by the Aircraft Morphing Program.

  6. Multidisciplinary Techniques and Novel Aircraft Control Systems

    NASA Technical Reports Server (NTRS)

    Padula, Sharon L.; Rogers, James L.; Raney, David L.

    2000-01-01

    The Aircraft Morphing Program at NASA Langley Research Center explores opportunities to improve airframe designs with smart technologies. Two elements of this basic research program are multidisciplinary design optimization (MDO) and advanced flow control. This paper describes examples where MDO techniques such as sensitivity analysis, automatic differentiation, and genetic algorithms contribute to the design of novel control systems. In the test case, the design and use of distributed shape-change devices to provide low-rate maneuvering capability for a tailless aircraft is considered. The ability of MDO to add value to control system development is illustrated using results from several years of research funded by the Aircraft Morphing Program.

  7. Aircraft anti-insect system

    NASA Technical Reports Server (NTRS)

    Spiro, Clifford Lawrence (Inventor); Fric, Thomas Frank (Inventor); Leon, Ross Michael (Inventor)

    1997-01-01

    Insect debris is removed from or prevented from adhering to insect impingement areas of an aircraft, particularly on an inlet cowl of an engine, by heating the area to 180.degree.-500.degree. C. An apparatus comprising a means to bring hot air from the aircraft engine to a plenum contiguous to the insect impingement area provides for the heating of the insect impingement areas to the required temperatures. The plenum can include at least one tube with a plurality of holes contained in a cavity within the inlet cowl. It can also include an envelope with a plurality of holes on its surface contained in a cavity within the inlet cowl.

  8. Vertical flight path steering system for aircraft

    NASA Technical Reports Server (NTRS)

    Lambregts, Antonius A. (Inventor)

    1983-01-01

    Disclosed is a vertical flight path angle steering system for aircraft, utilizing a digital flight control computer which processes pilot control inputs and aircraft response parameters into suitable elevator commands and control information for display to the pilot on a cathode ray tube. The system yields desirable airplane control handling qualities and responses as well as improvements in pilot workload and safety during airplane operation in the terminal area and under windshear conditions.

  9. Cooling system for high speed aircraft

    NASA Technical Reports Server (NTRS)

    Lawing, P. L.; Pagel, L. L. (Inventor)

    1981-01-01

    The system eliminates the necessity of shielding an aircraft airframe constructed of material such as aluminum. Cooling is accomplished by passing a coolant through the aircraft airframe, the coolant acting as a carrier to remove heat from the airframe. The coolant is circulated through a heat pump and a heat exchanger which together extract essentially all of the added heat from the coolant. The heat is transferred to the aircraft fuel system via the heat exchanger and the heat pump. The heat extracted from the coolant is utilized to power the heat pump. The heat pump has associated therewith power turbine mechanism which is also driven by the extracted heat. The power turbines are utilized to drive various aircraft subsystems, the compressor of the heat pump, and provide engine cooling.

  10. Electrical Generation for More-Electric Aircraft Using Solid Oxide Fuel Cells

    SciTech Connect

    Whyatt, Greg A.; Chick, Lawrence A.

    2012-04-01

    This report examines the potential for Solid-Oxide Fuel Cells (SOFC) to provide electrical generation on-board commercial aircraft. Unlike a turbine-based auxiliary power unit (APU) a solid oxide fuel cell power unit (SOFCPU) would be more efficient than using the main engine generators to generate electricity and would operate continuously during flight. The focus of this study is on more-electric aircraft which minimize bleed air extraction from the engines and instead use electrical power obtained from generators driven by the main engines to satisfy all major loads. The increased electrical generation increases the potential fuel savings obtainable through more efficient electrical generation using a SOFCPU. However, the weight added to the aircraft by the SOFCPU impacts the main engine fuel consumption which reduces the potential fuel savings. To investigate these relationships the Boeing 787­8 was used as a case study. The potential performance of the SOFCPU was determined by coupling flowsheet modeling using ChemCAD software with a stack performance algorithm. For a given stack operating condition (cell voltage, anode utilization, stack pressure, target cell exit temperature), ChemCAD software was used to determine the cathode air rate to provide stack thermal balance, the heat exchanger duties, the gross power output for a given fuel rate, the parasitic power for the anode recycle blower and net power obtained from (or required by) the compressor/expander. The SOFC is based on the Gen4 Delphi planar SOFC with assumed modifications to tailor it to this application. The size of the stack needed to satisfy the specified condition was assessed using an empirically-based algorithm. The algorithm predicts stack power density based on the pressure, inlet temperature, cell voltage and anode and cathode inlet flows and compositions. The algorithm was developed by enhancing a model for a well-established material set operating at atmospheric pressure to reflect the

  11. General Matrix Inversion Technique for the Calibration of Electric Field Sensor Arrays on Aircraft Platforms

    NASA Technical Reports Server (NTRS)

    Mach, D. M.; Koshak, W. J.

    2007-01-01

    A matrix calibration procedure has been developed that uniquely relates the electric fields measured at the aircraft with the external vector electric field and net aircraft charge. The calibration method can be generalized to any reasonable combination of electric field measurements and aircraft. A calibration matrix is determined for each aircraft that represents the individual instrument responses to the external electric field. The aircraft geometry and configuration of field mills (FMs) uniquely define the matrix. The matrix can then be inverted to determine the external electric field and net aircraft charge from the FM outputs. A distinct advantage of the method is that if one or more FMs need to be eliminated or deemphasized [e.g., due to a malfunction), it is a simple matter to reinvert the matrix without the malfunctioning FMs. To demonstrate the calibration technique, data are presented from several aircraft programs (ER-2, DC-8, Altus, and Citation).

  12. Internal-flow systems for aircraft

    NASA Technical Reports Server (NTRS)

    Rogallo, F M

    1941-01-01

    An investigation has been made to determine efficient arrangements for an internal-flow system of an aircraft when such a system operates by itself or in combination with other flow systems. The investigation included a theoretical treatment of the problem and tests in the NACA 5-foot vertical wind tunnel of inlet and outlet openings in a flat plate and in a wing.

  13. Affordable MMW aircraft collision avoidance system

    NASA Astrophysics Data System (ADS)

    Almsted, Larry D.; Becker, Robert C.; Zelenka, Richard E.

    1997-06-01

    Collision avoidance is of concern to all aircraft, requiring the detection and identification of hazardous terrain or obstacles in sufficient time for clearance maneuvers. The collision avoidance requirement is even more demanding for helicopters, as their unique capabilities result in extensive operations at low-altitude, near to terrain and other hazardous obstacles. TO augment the pilot's visual collision avoidance abilities, some aircraft are equipped with 'enhanced-vision' systems or terrain collision warning systems. Enhanced-vision systems are typically very large and costly systems that are not very covert and are also difficult to install in a helicopter. The display is typically raw images from infrared or radar sensors, and can require a high degree of pilot interpretation and attention. Terrain collision warning system that rely on stored terrain maps are often of low resolution and accuracy and do not represent hazards to the aircraft placed after map sampling. Such hazards could include aircraft parked on runway, man- made towers or buildings and hills. In this paper, a low cost dual-function scanning pencil-beam, millimeter-wave radar forward sensor is used to determine whether an aircraft's flight path is clear of obstructions. Due to the limited space and weight budget in helicopters, the system is a dual function system that is substituted in place of the existing radar altimeter. The system combines a 35 GHz forward looking obstacle avoidance radar and a 4.3 GHz radar altimeter. The forward looking 35 GHz 3D radar's returns are used to construct a terrain and obstruction database surrounding an aircraft, which is presented to the pilot as a synthetic perspective display. The 35 GHz forward looking radar and the associated display was evaluated in a joint NASA Honeywell flight test program in 1996. The tests were conducted on a NASA/Army test helicopter. The test program clearly demonstrated the systems potential usefulness for collision avoidance.

  14. Analytic Solution to the Problem of Aircraft Electric Field Mill Calibration

    NASA Technical Reports Server (NTRS)

    Koshak, William

    2003-01-01

    It is by no means a simple task to retrieve storm electric fields from an aircraft instrumented with electric field mill sensors. The presence of the aircraft distorts the ambient field in a complicated way. Before retrievals of the storm field can be made, the field mill measurement system must be "calibrated". In other words, a relationship between impressed (i.e., ambient) electric field and mill output must be established. If this relationship can be determined, it is mathematically inverted so that ambient field can be inferred from the mill outputs. Previous studies have primarily focused on linear theories where the relationship between ambient field and mill output is described by a "calibration matrix" M. Each element of the matrix describes how a particular component of the ambient field is enhanced by the aircraft. For example the product M(sub ix), E(sub x), is the contribution of the E(sub x) field to the i(th) mill output. Similarly, net aircraft charge (described by a "charge field component" E(sub q)) contributes an amount M(sub iq)E(sub q) to the output of the i(th) sensor. The central difficulty in obtaining M stems from the fact that the impressed field (E(sub x), E(sub y), E(sub z), E(sub q) is not known but is instead estimated. Typically, the aircraft is flown through a series of roll and pitch maneuvers in fair weather, and the values of the fair weather field and aircraft charge are estimated at each point along the aircraft trajectory. These initial estimates are often highly inadequate, but several investigators have improved the estimates by implementing various (ad hoc) iterative methods. Unfortunately, none of the iterative methods guarantee absolute convergence to correct values (i.e., absolute convergence to correct values has not been rigorously proven). In this work, the mathematical problem is solved directly by analytic means. For m mills installed on an arbitrary aircraft, it is shown that it is possible to solve for a single 2m

  15. Aircraft sensor analysis package system description

    NASA Technical Reports Server (NTRS)

    Forman, M. L.

    1977-01-01

    An overview of the capabilities of the Aircraft Sensor Analysis Package (ASAP) is presented. The approach is non-technical, and several output products are illustrated. The major features of the system are described in more detail than is found in the User's Guide to a potential user, or to a user looking for a specific capability to be incorporated in another system.

  16. An investigation of separate surface stability augmentation systems for general aviation aircraft

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The status of a project to develop and evaluate separate surface stability augmentation systems for general aviation aircraft is discussed. The electrical design, roll heading hold is described and schematic diagrams and an operational description are provided. The flight tests program is explained. Various failure conditions are proposed and the effects on the stability of the aircraft are analyzed.

  17. The Development of a Highly Reliable Power Management and Distribution System for Civil Transport Aircraft

    NASA Technical Reports Server (NTRS)

    Coleman, Anthony S.; Hansen, Irving G.

    1994-01-01

    NASA is pursuing a program in Advanced Subsonic Transport (AST) to develop the technology for a highly reliable Fly-By-Light/Power-By-WIre aircraft. One of the primary objectives of the program is to develop the technology base for confident application of integrated PBW components and systems to transport aircraft to improve operating reliability and efficiency. Technology will be developed so that the present hydraulic and pneumatic systems of the aircraft can be systematically eliminated and replaced by electrical systems. These motor driven actuators would move the aircraft wing surfaces as well as the rudder to provide steering controls for the pilot. Existing aircraft electrical systems are not flight critical and are prone to failure due to Electromagnetic Interference (EMI) (1), ground faults and component failures. In order to successfully implement electromechanical flight control actuation, a Power Management and Distribution (PMAD) System must be designed having a reliability of 1 failure in 10(exp +9) hours, EMI hardening and a fault tolerance architecture to ensure uninterrupted power to all aircraft flight critical systems. The focus of this paper is to analyze, define, and describe technically challenging areas associated with the development of a Power By Wire Aircraft and typical requirements to be established at the box level. The authors will attempt to propose areas of investigation, citing specific military standards and requirements that need to be revised to accommodate the 'More Electric Aircraft Systems'.

  18. Reconfiguration control system for an aircraft wing

    NASA Technical Reports Server (NTRS)

    Wakayama, Sean R. (Inventor)

    2008-01-01

    Independently deflectable control surfaces are located on the trailing edge of the wing of a blended wing-body aircraft. The reconfiguration control system of the present invention controls the deflection of each control surface to optimize the spanwise lift distribution across the wing for each of several flight conditions, e.g., cruise, pitch maneuver, and high lift at low speed. The control surfaces are deflected and reconfigured to their predetermined optimal positions when the aircraft is in each of the aforementioned flight conditions. With respect to cruise, the reconfiguration control system will maximize the lift to drag ratio and keep the aircraft trimmed at a stable angle of attack. In a pitch maneuver, the control surfaces are deflected to pitch the aircraft and increase lift. Moreover, this increased lift has its spanwise center of pressure shifted inboard relative to its location for cruise. This inboard shifting reduces the increased bending moment about the aircraft's x-axis occasioned by the increased pitch force acting normal to the wing. To optimize high lift at low speed, during take-off and landing for example, the control surfaces are reconfigured to increase the local maximum coefficient of lift at stall-critical spanwise locations while providing pitch trim with control surfaces that are not stall critical.

  19. Design and certification of low-cost distributed Control-By-Light aircraft control systems for part 25 aircraft

    NASA Astrophysics Data System (ADS)

    Morrison, Brian D.; Robillard, Michael N.

    1996-10-01

    Raytheon has developed and is certifying fault-tolerant low- cost distributed Control-By-LightTM technology for use in the next generation of Civil, Regional, and General Aviation aircraft. Distributed Control-By-LightTM holds significant promise when applied to complex sensor/actuator systems such as aircraft controls. CBLTM systems replace mechanical, hydraulic and electrical controls presently used to monitor, control and display flight, engine, and utility functions, and has substantial weight, cost, safety, and performance advantages over today's mechanical and Fly-By- Wire techniques. This paper describes the system concepts and outlines the formal certification program presently underway.

  20. Serial Escape System For Aircraft Crews

    NASA Technical Reports Server (NTRS)

    Wood, Kenneth E.

    1990-01-01

    Emergency escape system for aircraft and aerospace vehicles ejects up to seven crewmembers, one by one, within 120 s. Intended for emergencies in which disabled craft still in stable flight at no more than 220 kn (113 m/s) equivalent airspeed and sinking no faster than 110 ft/s (33.5 m/s) at altitudes up to 50,000 ft (15.2 km). Ejection rockets load themselves from magazine after each crewmember ejected. Jumpmaster queues other crewmembers and helps them position themselves on egress ramp. Rockets pull crewmembers clear of aircraft structure. Provides orderly, controlled exit and avoids ditching at sea or landing in rough terrain.

  1. A Turbo-Brayton Cryocooler for Aircraft Superconducting Systems

    NASA Technical Reports Server (NTRS)

    Dietz, Anthony

    2014-01-01

    Hybrid turboelectric aircraft-with gas turbines driving electric generators connected to electric propulsion motors-have the potential to transform aircraft design. Decoupling power generation from propulsion enables innovative aircraft designs, such as blended-wing bodies, with distributed propulsion. These hybrid turboelectric aircraft have the potential to significantly reduce emissions, decrease fuel burn, and reduce noise, all of which are required to make air transportation growth projections sustainable. The power density requirements for these electric machines can only be achieved with superconductors, which in turn require lightweight, high-capacity cryocoolers.

  2. Aircraft Environmental Systems Mechanic. Part 2.

    ERIC Educational Resources Information Center

    Chanute AFB Technical Training Center, IL.

    This packet contains learning modules designed for a self-paced course in aircraft environmental systems mechanics that was developed for the Air Force. Learning modules consist of some or all of the following materials: objectives, instructions, equipment, procedures, information sheets, handouts, workbooks, self-tests with answers, review…

  3. Aircraft Environmental Systems Mechanic. Part 1.

    ERIC Educational Resources Information Center

    Chanute AFB Technical Training Center, IL.

    This packet contains learning modules for a self-paced course in aircraft environmental systems mechanics that was developed for the Air Force. Each learning module consists of some or all of the following: objectives, instructions, equipment, procedures, information sheets, handouts, self-tests with answers, review section, tests, and response…

  4. Rotor systems research aircraft simulation mathematical model

    NASA Technical Reports Server (NTRS)

    Houck, J. A.; Moore, F. L.; Howlett, J. J.; Pollock, K. S.; Browne, M. M.

    1977-01-01

    An analytical model developed for evaluating and verifying advanced rotor concepts is discussed. The model was used during in both open loop and real time man-in-the-loop simulation during the rotor systems research aircraft design. Future applications include: pilot training, preflight of test programs, and the evaluation of promising concepts before their implementation on the flight vehicle.

  5. Aircraft signal definition for flight safety system monitoring system

    NASA Technical Reports Server (NTRS)

    Gibbs, Michael (Inventor); Omen, Debi Van (Inventor)

    2003-01-01

    A system and method compares combinations of vehicle variable values against known combinations of potentially dangerous vehicle input signal values. Alarms and error messages are selectively generated based on such comparisons. An aircraft signal definition is provided to enable definition and monitoring of sets of aircraft input signals to customize such signals for different aircraft. The input signals are compared against known combinations of potentially dangerous values by operational software and hardware of a monitoring function. The aircraft signal definition is created using a text editor or custom application. A compiler receives the aircraft signal definition to generate a binary file that comprises the definition of all the input signals used by the monitoring function. The binary file also contains logic that specifies how the inputs are to be interpreted. The file is then loaded into the monitor function, where it is validated and used to continuously monitor the condition of the aircraft.

  6. Aircraft Weather Mitigation for the Next Generation Air Transportation System

    NASA Technical Reports Server (NTRS)

    Stough, H. Paul, III

    2007-01-01

    Atmospheric effects on aviation are described by Mahapatra (1999) as including (1) atmospheric phenomena involving air motion - wind shear and turbulence; (2) hydrometeorological phenomena - rain, snow and hail; (3) aircraft icing; (4) low visibility; and (5) atmospheric electrical phenomena. Aircraft Weather Mitigation includes aircraft systems (e.g. airframe, propulsion, avionics, controls) that can be enacted (by a pilot, automation or hybrid systems) to suppress and/or prepare for the effects of encountered or unavoidable weather or to facilitate a crew operational decision-making process relative to weather. Aircraft weather mitigation can be thought of as a continuum (Figure 1) with the need to avoid all adverse weather at one extreme and the ability to safely operate in all weather conditions at the other extreme. Realistic aircraft capabilities fall somewhere between these two extremes. The capabilities of small general aviation aircraft would be expected to fall closer to the "Avoid All Adverse Weather" point, and the capabilities of large commercial jet transports would fall closer to the "Operate in All Weather Conditions" point. The ability to safely operate in adverse weather conditions is dependent upon the pilot s capabilities (training, total experience and recent experience), the airspace in which the operation is taking place (terrain, navigational aids, traffic separation), the capabilities of the airport (approach guidance, runway and taxiway lighting, availability of air traffic control), as well as the capabilities of the airplane. The level of mitigation may vary depending upon the type of adverse weather. For example, a small general aviation airplane may be equipped to operate "in the clouds" without outside visual references, but not be equipped to prevent airframe ice that could be accreted in those clouds.

  7. Transport aircraft loading and balancing system: Using a CLIPS expert system for military aircraft load planning

    NASA Technical Reports Server (NTRS)

    Richardson, J.; Labbe, M.; Belala, Y.; Leduc, Vincent

    1994-01-01

    The requirement for improving aircraft utilization and responsiveness in airlift operations has been recognized for quite some time by the Canadian Forces. To date, the utilization of scarce airlift resources has been planned mainly through the employment of manpower-intensive manual methods in combination with the expertise of highly qualified personnel. In this paper, we address the problem of facilitating the load planning process for military aircraft cargo planes through the development of a computer-based system. We introduce TALBAS (Transport Aircraft Loading and BAlancing System), a knowledge-based system designed to assist personnel involved in preparing valid load plans for the C130 Hercules aircraft. The main features of this system which are accessible through a convivial graphical user interface, consists of the automatic generation of valid cargo arrangements given a list of items to be transported, the user-definition of load plans and the automatic validation of such load plans.

  8. Analysis and testing of aeroelastic model stability augmentation systems. [for supersonic transport aircraft wing and B-52 aircraft control system

    NASA Technical Reports Server (NTRS)

    Sevart, F. D.; Patel, S. M.

    1973-01-01

    Testing and evaluation of a stability augmentation system for aircraft flight control were performed. The flutter suppression system and synthesis conducted on a scale model of a supersonic wing for a transport aircraft are discussed. Mechanization and testing of the leading and trailing edge surface actuation systems are described. The ride control system analyses for a 375,000 pound gross weight B-52E aircraft are presented. Analyses of the B-52E aircraft maneuver load control system are included.

  9. Control technology for future aircraft propulsion systems

    NASA Technical Reports Server (NTRS)

    Zeller, J. R.; Szuch, J. R.; Merrill, W. C.; Lehtinen, B.; Soeder, J. F.

    1984-01-01

    The need for a more sophisticated engine control system is discussed. The improvements in better thrust-to-weight ratios demand the manipulation of more control inputs. New technological solutions to the engine control problem are practiced. The digital electronic engine control (DEEC) system is a step in the evolution to digital electronic engine control. Technology issues are addressed to ensure a growth in confidence in sophisticated electronic controls for aircraft turbine engines. The need of a control system architecture which permits propulsion controls to be functionally integrated with other aircraft systems is established. Areas of technology studied include: (1) control design methodology; (2) improved modeling and simulation methods; and (3) implementation technologies. Objectives, results and future thrusts are summarized.

  10. An adaptive learning control system for aircraft

    NASA Technical Reports Server (NTRS)

    Mekel, R.; Nachmias, S.

    1976-01-01

    A learning control system is developed which blends the gain scheduling and adaptive control into a single learning system that has the advantages of both. An important feature of the developed learning control system is its capability to adjust the gain schedule in a prescribed manner to account for changing aircraft operating characteristics. Furthermore, if tests performed by the criteria of the learning system preclude any possible change in the gain schedule, then the overall system becomes an ordinary gain scheduling system. Examples are discussed.

  11. Tribological systems as applied to aircraft engines

    NASA Technical Reports Server (NTRS)

    Buckley, D. H.

    1985-01-01

    Tribological systems as applied to aircraft are reviewed. The importance of understanding the fundamental concepts involved in such systems is discussed. Basic properties of materials which can be related to adhesion, friction and wear are presented and correlated with tribology. Surface processes including deposition and treatment are addressed in relation to their present and future application to aircraft components such as bearings, gears and seals. Lubrication of components with both liquids and solids is discussed. Advances in both new liquid molecular structures and additives for those structures are reviewed and related to the needs of advanced engines. Solids and polymer composites are suggested for increasing use and ceramic coatings containing fluoride compounds are offered for the extreme temperatures encountered in such components as advanced bearings and seals.

  12. Active Aircraft Pylon Noise Control System

    NASA Technical Reports Server (NTRS)

    Thomas, Russell H. (Inventor); Czech, Michael J (Inventor); Elmiligui, Alaa A. (Inventor)

    2015-01-01

    An active pylon noise control system for an aircraft includes a pylon structure connecting an engine system with an airframe surface of the aircraft and having at least one aperture to supply a gas or fluid therethrough, an intake portion attached to the pylon structure to intake a gas or fluid, a regulator connected with the intake portion via a plurality of pipes, to regulate a pressure of the gas or fluid, a plenum chamber formed within the pylon structure and connected with the regulator, and configured to receive the gas or fluid as regulated by the regulator, and a plurality of injectors in communication with the plenum chamber to actively inject the gas or fluid through the plurality of apertures of the pylon structure.

  13. Ride quality systems for commuter aircraft

    NASA Technical Reports Server (NTRS)

    Downing, D. R.; Hammond, T. A.; Amin, S. P.

    1983-01-01

    The state-of-the-art in Active Ride Augmentation, specifically in terms of its feasibility for commuter aircraft applications. A literature survey was done, and the principal results are presented here through discussion of different Ride Quality Augmentation System (RQAS) designs and advances in related technologies. Recommended follow-on research areas are discussed, and a preliminary RQAS configuration for detailed design and development is proposed.

  14. Emergency Control Aircraft System Using Thrust Modulation

    NASA Technical Reports Server (NTRS)

    Burken, John J. (Inventor); Burcham, Frank W., Jr. (Inventor)

    2000-01-01

    A digital longitudinal Aircraft Propulsion Control (APC system of a multiengine aircraft is provided by engine thrust modulation in response to comparing an input flightpath angle signal (gamma)c from a pilot thumbwheel. or an ILS system with a sensed flightpath angle y to produce an error signal (gamma)e that is then integrated (with reasonable limits) to generate a drift correction signal to be added to the error signal (gamma)e after first subtracting a lowpass filtered velocity signal Vel(sub f) for phugoid damping. The output error signal is multiplied by a constant to produce an aircraft thrust control signal ATC of suitable amplitude to drive a throttle servo for all engines. each of which includes its own full-authority digital engine control (FADEC) computer. An alternative APC system omits sensed flightpath angle feedback and instead controls the flightpath angle by feedback of the lowpass filtered velocity signal Vel(sub f) which also inherently provides phugoid damping. The feature of drift compensation is retained.

  15. Small Aircraft Transportation System Concept and Technologies

    NASA Technical Reports Server (NTRS)

    Holmes, Bruce J.; Durham, Michael H.; Tarry, Scott E.

    2005-01-01

    This paper summarizes both the vision and the early public-private collaborative research for the Small Aircraft Transportation System (SATS). The paper outlines an operational definition of SATS, describes how SATS conceptually differs from current air transportation capabilities, introduces four SATS operating capabilities, and explains the relation between the SATS operating capabilities and the potential for expanded air mobility. The SATS technology roadmap encompasses on-demand, widely distributed, point-to-point air mobility, through hired-pilot modes in the nearer-term, and through self-operated user modes in the farther-term. The nearer-term concept is based on aircraft and airspace technologies being developed to make the use of smaller, more widely distributed community reliever and general aviation airports and their runways more useful in more weather conditions, in commercial hired-pilot service modes. The farther-term vision is based on technical concepts that could be developed to simplify or automate many of the operational functions in the aircraft and the airspace for meeting future public transportation needs, in personally operated modes. NASA technology strategies form a roadmap between the nearer-term concept and the farther-term vision. This paper outlines a roadmap for scalable, on-demand, distributed air mobility technologies for vehicle and airspace systems. The audiences for the paper include General Aviation manufacturers, small aircraft transportation service providers, the flight training industry, airport and transportation authorities at the Federal, state and local levels, and organizations involved in planning for future National Airspace System advancements.

  16. Electrical short circuit and current overload tests on aircraft wiring

    NASA Technical Reports Server (NTRS)

    Cahill, Patricia

    1995-01-01

    The findings of electrical short circuit and current overload tests performed on commercial aircraft wiring are presented. A series of bench-scale tests were conducted to evaluate circuit breaker response to overcurrent and to determine if the wire showed any visible signs of thermal degradation due to overcurrent. Three types of wire used in commercial aircraft were evaluated: MIL-W-22759/34 (150 C rated), MIL-W-81381/12 (200 C rated), and BMS 1360 (260 C rated). A second series of tests evaluated circuit breaker response to short circuits and ticking faults. These tests were also meant to determine if the three test wires behaved differently under these conditions and if a short circuit or ticking fault could start a fire. It is concluded that circuit breakers provided reliable overcurrent protection. Circuit breakers may not protect wire from ticking faults but can protect wire from direct shorts. These tests indicated that the appearance of a wire subjected to a current that totally degrades the insulation looks identical to a wire subjected to a fire; however the 'fire exposed' conductor was more brittle than the conductor degraded by overcurrent. Preliminary testing indicates that direct short circuits are not likely to start a fire. Preliminary testing indicated that direct short circuits do not erode insulation and conductor to the extent that ticking faults did. Circuit breakers may not safeguard against the ignition of flammable materials by ticking faults. The flammability of materials near ticking faults is far more important than the rating of the wire insulation material.

  17. A system approach to aircraft optimization

    NASA Technical Reports Server (NTRS)

    Sobieszczanski-Sobieski, Jaroslaw

    1991-01-01

    Mutual couplings among the mathematical models of physical phenomena and parts of a system such as an aircraft complicate the design process because each contemplated design change may have a far reaching consequence throughout the system. Techniques are outlined for computing these influences as system design derivatives useful for both judgemental and formal optimization purposes. The techniques facilitate decomposition of the design process into smaller, more manageable tasks and they form a methodology that can easily fit into existing engineering organizations and incorporate their design tools.

  18. Analysis of cooling systems for hypersonic aircraft

    NASA Technical Reports Server (NTRS)

    Petley, Dennis H.; Jones, Stuart C.; Dziedzic, William M.

    1991-01-01

    A computer program has been written to analyze cooling systems of hypersonic aircraft. This computer program called NASP/SINDA is written into the SINDA'85 command structure and uses the SINDA'85 finite difference subroutines. Both internal fluid flow and heat transfer must be analyzed, because increased heating causes a decrease in the flow of the coolant. Also local hot spots will cause a redistribution of the coolant in the system. Both steady state and transient analyses have been performed. Details of empirical correlations are presented. Results for two cooling system applications are given.

  19. Fires in P-3 Aircraft Oxygen Systems

    NASA Technical Reports Server (NTRS)

    Stoltzfus, Joel

    2006-01-01

    Fires in three P3 aircraft oxygen systems have occurred: one in the Royal Australian Air Force (RAAF) in 1984 and two in the U.S. Navy in 1998 and 2003. All three fires started in the aluminum manifold and check valve (MCV) assembly and produced similar damages to the aircraft in which they occurred. This paper discusses a failure analysis conducted by the NASA Johnson Space Center White Sands Test Facility (WSTF) Oxygen Hazards and Testing Team on the 2003 U.S. Navy VP62 fire. It was surmised that the fire started due to heat generated by an oxygen leak past a silicone check valve seal or possibly because of particle impact near the seat of one of the MCV assembly check valves. An additional analysis of fires in several check valve poppet seals from other aircraft is discussed. These burned poppet seals came from P3 oxygen systems that had been serviced at the Naval Air Station (NAS) in Jacksonville following standard fill procedures. It was concluded that these seal fires occurred due to the heat from compression heating, particle impact, or the heat generated by an oxygen leak past the silicone check valve seal. The fact that catastrophic fires did not occur in the case of each check valve seal fire was attributed to the protective nature of the aluminum oxide layer on the check valve poppets. To prevent future fires of this nature, the U.S. and Canadian fleets of P3 aircraft have been retrofitted with MCV assemblies with an upgraded design and more burn-resistant materials.

  20. Turboprop Cargo Aircraft Systems study, phase 1

    NASA Technical Reports Server (NTRS)

    Muehlbauer, J. C.; Hewell, J. G., Jr.; Lindenbaum, S. P.; Randall, C. C.; Searle, N.; Stone, F. R., Jr.

    1980-01-01

    The effects of advanced propellers (propfan) on aircraft direct operating costs, fuel consumption, and noiseprints were determined. A comparison of three aircraft selected from the results with competitive turbofan aircraft shows that advanced turboprop aircraft offer these potential benefits, relative to advanced turbofan aircraft: 21 percent fuel saving, 26 percent higher fuel efficiency, 15 percent lower DOCs, and 25 percent shorter field lengths. Fuel consumption for the turboprop is nearly 40 percent less than for current commercial turbofan aircraft. Aircraft with both types of propulsion satisfy current federal noise regulations. Advanced turboprop aircraft have smaller noiseprints at 90 EPNdB than advanced turbofan aircraft, but large noiseprints at 70 and 80 EPNdB levels, which are usually suggested as quietness goals. Accelerated development of advanced turboprops is strongly recommended to permit early attainment of the potential fuel saving. Several areas of work are identified which may produce quieter turboprop aircraft.

  1. A local authority aircraft noise monitoring system

    NASA Astrophysics Data System (ADS)

    Vulkan, G.; Hyde, J.

    1981-06-01

    Aircraft noise exposure levels recorded at London's Heathrow airport are analyzed for the purpose of noise abatement policy-making. The basic equipment consisted of a data logger capable of recording an eight-bit phase encoded binary signal at 0.5 second intervals on standard audio cassettes. The mean peak landing noise for a month was 85 dB(A) by day, increasing to 85.4 dB(A) by night, while take-off noise dropped from 87.7 dB(A) by day to 82.8 dB(A) at night. Although it had been anticipated that noise from landing aircraft would generally be less than that from departing aircraft, results so far indicate little difference. It is concluded that selection of groups of data based on time period, runway in use and weather conditions parameters can be provided by the system, enabling thus assessments to be made in planning and designing of buildings.

  2. NASA Aircraft Vortex Spacing System Development Status

    NASA Technical Reports Server (NTRS)

    Hinton, David A.; Charnock, James K.; Bagwell, Donald R.; Grigsby, Donner

    1999-01-01

    The National Aeronautics and Space Administration (NASA) is addressing airport capacity enhancements during instrument meteorological conditions through the Terminal Area Productivity (TAP) program. Within TAP, the Reduced Spacing Operations (RSO) subelement at the NASA Langley Research Center is developing an Aircraft VOrtex Spacing System (AVOSS). AVOSS will integrate the output of several systems to produce weather dependent, dynamic wake vortex spacing criteria. These systems provide current and predicted weather conditions, models of wake vortex transport and decay in these weather conditions, and real-time feedback of wake vortex behavior from sensors. The goal of the NASA program is to provide the research and development to demonstrate an engineering model AVOSS in real-time operation at a major airport. The demonstration is only of concept feasibility, and additional effort is required to deploy an operational system for actual aircraft spacing reduction. This paper describes the AVOSS system architecture, a wake vortex facility established at the Dallas-Fort Worth International Airport (DFW), initial operational experience with the AVOSS system, and emerging considerations for subsystem requirements. Results of the initial system operation suggest a significant potential for reduced spacing.

  3. Microwave System for Detecting Ice on Aircraft

    NASA Technical Reports Server (NTRS)

    Joseph, Philip J.; Glynn, Dennis P., Jr.; Joseph, John C.

    2004-01-01

    A microwave-based system has been developed as a means of detecting ice on aircraft surfaces, with enough sensitivity to provide a warning before the ice accretes to a dangerous thickness. The system can measure the thickness of ice from a few mils (1 mil = 0.0254 mm) to about 1/4 in. (.6 mm) and can distinguish among (1) ice, (2) water (or deicing fluid), and (3) a mixture of ice and water (or deicing fluid). Sensors have been ruggedized to withstand the rain erosion environment.

  4. Internal-flow systems for aircraft

    NASA Technical Reports Server (NTRS)

    Rogallo, F M

    1940-01-01

    An investigation has been made to determine efficient arrangements for an internal-flow system of an aircraft when such a system operates by itself or in combination with other flow systems. The investigation included a theoretical treatment of a problem and tests in the NACA 5-foot vertical wind tunnel of inlet and outlet openings in a flat plate and in a wing. When an internal-flow system tends to decrease the final velocity of it's wake, the results showed that it should be arranged in series with the propulsive system; the inlet opening should be located at a forward stagnation point; and the outlet opening should be so shaped and located as to recover the kinetic energy of the jet without increasing the drag of other portions of the aircraft. When an internal-flow system tends to increase the final velocity new b's wake, as does a propeller, location of the inlet opening in the boundary layer or in the wake of the wing or in the fuselage may be desirable.

  5. General Matrix Inversion for the Calibration of Electric Field Sensor Arrays on Aircraft Platforms

    NASA Technical Reports Server (NTRS)

    Mach, D. M.; Koshak, W. J.

    2006-01-01

    We have developed a matrix calibration procedure that uniquely relates the electric fields measured at the aircraft with the external vector electric field and net aircraft charge. Our calibration method is being used with all of our aircraft/electric field sensing combinations and can be generalized to any reasonable combination of electric field measurements and aircraft. We determine a calibration matrix that represents the individual instrument responses to the external electric field. The aircraft geometry and configuration of field mills (FMs) uniquely define the matrix. The matrix can then be inverted to determine the external electric field and net aircraft charge from the FM outputs. A distinct advantage of the method is that if one or more FMs need to be eliminated or de-emphasized (for example, due to a malfunction), it is a simple matter to reinvert the matrix without the malfunctioning FMs. To demonstrate our calibration technique, we present data from several of our aircraft programs (ER-2, DC-8, Altus, Citation).

  6. An Immunized Aircraft Maneuver Selection System

    NASA Technical Reports Server (NTRS)

    Karr, Charles L.

    2003-01-01

    The objective of this project, as stated in the original proposal, was to develop an immunized aircraft maneuver selection (IAMS) system. The IAMS system was to be composed of computational and informational building blocks that resemble structures in natural immune systems. The ultimate goal of the project was to develop a software package that could be flight tested on aircraft models. This report describes the work performed in the first year of what was to have been a two year project. This report also describes efforts that would have been made in the final year to have completed the project, had it been continued for the final year. After introductory material is provided in Section 2, the end-of-year-one status of the effort is discussed in Section 3. The remainder of the report provides an accounting of first year efforts. Section 4 provides background information on natural immune systems while Section 5 describes a generic ar&itecture developed for use in the IAMS. Section 6 describes the application of the architecture to a system identification problem. Finally, Section 7 describes steps necessary for completing the project.

  7. Aircraft engine mathematical model - linear system approach

    NASA Astrophysics Data System (ADS)

    Rotaru, Constantin; Roateşi, Simona; Cîrciu, Ionicǎ

    2016-06-01

    This paper examines a simplified mathematical model of the aircraft engine, based on the theory of linear and nonlinear systems. The dynamics of the engine was represented by a linear, time variant model, near a nominal operating point within a finite time interval. The linearized equations were expressed in a matrix form, suitable for the incorporation in the MAPLE program solver. The behavior of the engine was included in terms of variation of the rotational speed following a deflection of the throttle. The engine inlet parameters can cover a wide range of altitude and Mach numbers.

  8. Metal matrix composites for aircraft propulsion systems

    NASA Technical Reports Server (NTRS)

    Signorelli, R. A.

    1975-01-01

    Studies of advanced aircraft propulsion systems have indicated that performance gains and operating costs are possible through the application of metal matrix composites. Compressor fan blades and turbine blades have been identified as components with high payoff potential as a result of these studies. This paper will present the current status of development of five candidate materials for such applications. Boron fiber/aluminum, boron fiber/titanium, and silicon carbide fiber/titanium composites are considered for lightweight compressor fan blades. Directionally solidified eutectic superalloy and tungsten wire/superalloy composites are considered for application to turbine blades for use temperatures to 1100 C (2000 F).

  9. Immunity-Based Aircraft Fault Detection System

    NASA Technical Reports Server (NTRS)

    Dasgupta, D.; KrishnaKumar, K.; Wong, D.; Berry, M.

    2004-01-01

    In the study reported in this paper, we have developed and applied an Artificial Immune System (AIS) algorithm for aircraft fault detection, as an extension to a previous work on intelligent flight control (IFC). Though the prior studies had established the benefits of IFC, one area of weakness that needed to be strengthened was the control dead band induced by commanding a failed surface. Since the IFC approach uses fault accommodation with no detection, the dead band, although it reduces over time due to learning, is present and causes degradation in handling qualities. If the failure can be identified, this dead band can be further A ed to ensure rapid fault accommodation and better handling qualities. The paper describes the application of an immunity-based approach that can detect a broad spectrum of known and unforeseen failures. The approach incorporates the knowledge of the normal operational behavior of the aircraft from sensory data, and probabilistically generates a set of pattern detectors that can detect any abnormalities (including faults) in the behavior pattern indicating unsafe in-flight operation. We developed a tool called MILD (Multi-level Immune Learning Detection) based on a real-valued negative selection algorithm that can generate a small number of specialized detectors (as signatures of known failure conditions) and a larger set of generalized detectors for unknown (or possible) fault conditions. Once the fault is detected and identified, an adaptive control system would use this detection information to stabilize the aircraft by utilizing available resources (control surfaces). We experimented with data sets collected under normal and various simulated failure conditions using a piloted motion-base simulation facility. The reported results are from a collection of test cases that reflect the performance of the proposed immunity-based fault detection algorithm.

  10. NASA's UAS [Unmanned Aircraft Systems] Related Activities

    NASA Technical Reports Server (NTRS)

    Bauer, Jeffrey

    2012-01-01

    NASA continues to operate all sizes of UAS in all classes of airspace both domestically and internationally. Missions range from highly complex operations in coordination with piloted aircraft, ground, and space systems in support of science objectives to single aircraft operations in support of aeronautics research. One such example is a scaled commercial transport aircraft being used to study recovery techniques due to large upsets. NASA's efforts to support routine UAS operations continued on several fronts last year. At the national level in the United States (U.S.), NASA continued its support of the UAS Executive Committee (ExCom) comprised of the Federal Aviation Administration (FAA), Department of Defense (DoD), Department of Homeland Security (DHS), and NASA. The committee was formed in recognition of the need of UAS operated by these agencies to access to the National Airspace System (NAS) to support operational, training, development and research requirements. Recommendations were received on how to operate both manned and unmanned aircraft in class D airspace and plans are being developed to validate and implement those recommendations. In addition the UAS ExCom has begun developing recommendations for how to achieve routine operations in remote areas as well as for small UAS operations in class G airspace. As well as supporting the UAS ExCom, NASA is a participant in the recently formed Aviation Rule Making Committee for UAS. This committee, established by the FAA, is intended to propose regulatory guidance which would enable routine civil UAS operations. As that effort matures NASA stands ready to supply the necessary technical expertise to help that committee achieve its objectives. By supporting both the UAS ExCom and UAS ARC, NASA is positioned to provide its technical expertise across the full spectrum of UAS airspace access related topic areas. The UAS NAS Access Project got underway this past year under the leadership of NASA s Aeronautics

  11. An adaptive learning control system for aircraft

    NASA Technical Reports Server (NTRS)

    Mekel, R.; Nachmias, S.

    1978-01-01

    A learning control system and its utilization as a flight control system for F-8 Digital Fly-By-Wire (DFBW) research aircraft is studied. The system has the ability to adjust a gain schedule to account for changing plant characteristics and to improve its performance and the plant's performance in the course of its own operation. Three subsystems are detailed: (1) the information acquisition subsystem which identifies the plant's parameters at a given operating condition; (2) the learning algorithm subsystem which relates the identified parameters to predetermined analytical expressions describing the behavior of the parameters over a range of operating conditions; and (3) the memory and control process subsystem which consists of the collection of updated coefficients (memory) and the derived control laws. Simulation experiments indicate that the learning control system is effective in compensating for parameter variations caused by changes in flight conditions.

  12. STBC AF relay for unmanned aircraft system

    NASA Astrophysics Data System (ADS)

    Adachi, Fumiyuki; Miyazaki, Hiroyuki; Endo, Chikara

    2015-01-01

    If a large scale disaster similar to the Great East Japan Earthquake 2011 happens, some areas may be isolated from the communications network. Recently, unmanned aircraft system (UAS) based wireless relay communication has been attracting much attention since it is able to quickly re-establish the connection between isolated areas and the network. However, the channel between ground station (GS) and unmanned aircraft (UA) is unreliable due to UA's swing motion and as consequence, the relay communication quality degrades. In this paper, we introduce space-time block coded (STBC) amplify-and-forward (AF) relay for UAS based wireless relay communication to improve relay communication quality. A group of UAs forms single frequency network (SFN) to perform STBC-AF cooperative relay. In STBC-AF relay, only conjugate operation, block exchange and amplifying are required at UAs. Therefore, STBC-AF relay improves the relay communication quality while alleviating the complexity problem at UAs. It is shown by computer simulation that STBC-AF relay can achieve better throughput performance than conventional AF relay.

  13. RSRA flight control and stabilization. [Rotor Systems Research Aircraft

    NASA Technical Reports Server (NTRS)

    Linden, A. W.

    1976-01-01

    Handling qualities of the RSRA (rotor systems research aircraft), a special test vehicle with optional configurations (forewings, removable horizontal tailplanes, main rotor, tail rotor, and twin engines for forward flight all removable), are described. The aircraft can be fitted to fly as a conventional rotary-wing aircraft, fixed-wing aircraft, or compound helicopter, and is designed for testing existing and future rotor systems in flight. Controls include full-authority fly-by-wire controls and mechanical controls for rotary wing and for fixed wing. Stability augmentation, rotor test measurement systems, variable center of gravity capability, and rotor loading potential of the RSRA are also described.

  14. 77 FR 14319 - Unmanned Aircraft System Test Sites

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-09

    ... can be found in the Federal Register published on April 11, 2000 (65 FR 19477-19478), as well as at... Federal Aviation Administration 14 CFR Part 91 Unmanned Aircraft System Test Sites AGENCY: Federal... test ranges/sites to integrate unmanned aircraft systems (UAS) into the National Airspace System...

  15. System design requirements for advanced rotary-wing agricultural aircraft

    NASA Technical Reports Server (NTRS)

    Lemont, H. E.

    1979-01-01

    Helicopter aerial dispersal systems were studied to ascertain constraints to the system, the effects of removal of limitations (technical and FAA regulations), and subsystem improvements. Productivity indices for the aircraft and swath effects were examined. Typical missions were formulated through conversations with operators, and differing gross weight aircraft were synthesized to perform these missions. Economic analysis of missions and aircraft indicated a general correlation of small aircraft (3000 lb gross weight) suitability for small fields (25 acres), and low dispersion rates (less than 32 lb/acre), with larger aircraft (12,000 lb gross weight) being more favorable for bigger fields (200 acres) and heavier dispersal rates (100 lb/acre). Operator problems, possible aircraft and system improvements, and selected removal of operating limitations were reviewed into recommendations for future NASA research items.

  16. Challenges of future aircraft propulsion: A review of distributed propulsion technology and its potential application for the all electric commercial aircraft

    NASA Astrophysics Data System (ADS)

    Gohardani, Amir S.; Doulgeris, Georgios; Singh, Riti

    2011-07-01

    This paper highlights the role of distributed propulsion technology for future commercial aircraft. After an initial historical perspective on the conceptual aspects of distributed propulsion technology and a glimpse at numerous aircraft that have taken distributed propulsion technology to flight, the focal point of the review is shifted towards a potential role this technology may entail for future commercial aircraft. Technological limitations and challenges of this specific technology are also considered in combination with an all electric aircraft concept, as means of predicting the challenges associated with the design process of a next generation commercial aircraft.

  17. Airbag system and method for facilitating emergency egress from an aircraft

    NASA Technical Reports Server (NTRS)

    Rawdon, Blaine K. (Inventor); Hawley, Arthur V. (Inventor)

    2002-01-01

    An airbag system for elevating the fuselage of an aircraft off a landing surface a sufficient degree to allow for emergency egress of passengers and crew through ventral emergency exit doors. An airbag assembly made up of a plurality of independent airbags is disposed within the aircraft. When activated, the airbag system deploys the airbags external of the aircraft that elevate the fuselage of the aircraft a sufficient degree to allow for utilizing the ventral emergency exit doors on the fuselage to enable evacuating the passengers and crew. An activation mechanism is connected to the inflation.devices associated with each of the airbags. The activation mechanism generates an electrical signal which activates the inflation devices, which in turn fill the airbags with a compressed fluid, thus expanding the airbags and lifting the fuselage. A crew member initiates the activation of the airbag system through one or more switches.

  18. Small Aircraft Transportation System Higher Volume Operations Concept

    NASA Technical Reports Server (NTRS)

    Abbott, Terence S.; Consiglio, Maria C.; Baxley, Brian T.; Williams, Daniel M.; Jones, Kenneth M.; Adams, Catherine A.

    2006-01-01

    This document defines the Small Aircraft Transportation System (SATS) Higher Volume Operations concept. The general philosophy underlying this concept is the establishment of a newly defined area of flight operations called a Self-Controlled Area (SCA). Within the SCA, pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft. This document also provides details for a number of off-nominal and emergency procedures which address situations that could be expected to occur in a future SCA. The details for this operational concept along with a description of candidate aircraft systems to support this concept are provided.

  19. Crew systems and flight station concepts for a 1995 transport aircraft

    NASA Technical Reports Server (NTRS)

    Sexton, G. A.

    1983-01-01

    Aircraft functional systems and crew systems were defined for a 1995 transport aircraft through a process of mission analysis, preliminary design, and evaluation in a soft mockup. This resulted in a revolutionary pilot's desk flight station design featuring an all-electric aircraft, fly-by-wire/light flight and thrust control systems, large electronic color head-down displays, head-up displays, touch panel controls for aircraft functional systems, voice command and response systems, and air traffic control systems projected for the 1990s. The conceptual aircraft, for which crew systems were designed, is a generic twin-engine wide-body, low-wing transport, capable of worldwide operation. The flight control system consists of conventional surfaces (some employed in unique ways) and new surfaces not used on current transports. The design will be incorporated into flight simulation facilities at NASA-Langley, NASA-Ames, and the Lockheed-Georgia Company. When interfaced with advanced air traffic control system models, the facilities will provide full-mission capability for researching issues affecting transport aircraft flight stations and crews of the 1990s.

  20. National Unmanned Aircraft Systems Project Office

    USGS Publications Warehouse

    Goplen, Susan E.; Sloan, Jeff L.

    2015-01-01

    The U.S. Geological Survey (USGS) National Unmanned Aircraft Systems (UAS) Project Office leads the implementation of UAS technology in the Department of the Interior (DOI). Our mission is to support the transition of UAS into DOI as a new cost-effective tool for collecting remote-sensing data to monitor environmental conditions, respond to natural hazards, recognize the consequences and benefits of land and climate change and conduct wildlife inventories. The USGS is teaming with all DOI agencies and academia as well as local, State, and Tribal governments with guidance from the Federal Aviation Administration and the DOI Office of Aviation Services (OAS) to lead the safe, efficient, costeffective and leading-edge adoption of UAS technology into the scientific research and operational activities of the DOI.

  1. Stability, Transient Response, Control, and Safety of a High-Power Electric Grid for Turboelectric Propulsion of Aircraft

    NASA Technical Reports Server (NTRS)

    Armstrong, Michael; Ross, Christine; Phillips, Danny; Blackwelder, Mark

    2013-01-01

    This document contains the deliverables for the NASA Research and Technology for Aerospace Propulsion Systems (RTAPS) regarding the stability, transient response, control, and safety study for a high power cryogenic turboelectric distributed propulsion (TeDP) system. The objective of this research effort is to enumerate, characterize, and evaluate the critical issues facing the development of the N3-X concept aircraft. This includes the proposal of electrical grid architecture concepts and an evaluation of any needs for energy storage.

  2. Solar Powered Aircraft, Photovoltaic Array/Battery System Tabletop Demonstration: Design and Operation Manual

    NASA Technical Reports Server (NTRS)

    Colozza, Anthony J.; Scheiman, David A.; Bailey, Sheila (Technical Monitor)

    2000-01-01

    A system was constructed to demonstrate the power system operation of a solar powered aircraft. The system consists of a photovoltaic (PV) array, a charge controller, a battery, an electric motor and propeller. The system collects energy from the PV array and either utilizes this energy to operate an electric motor or stores it in a rechargeable battery for future use. The system has a control panel which displays the output of the array and battery as well as the total current going to the electric motor. The control panel also has a means for adjusting the output to the motor to control its speed. The entire system is regulated around 12 VDC.

  3. Aircraft Engine Exhaust Nozzle System for Jet Noise Reduction

    NASA Technical Reports Server (NTRS)

    Thomas, Russell H. (Inventor); Czech, Michael J. (Inventor); Elkoby, Ronen (Inventor)

    2014-01-01

    The aircraft exhaust engine nozzle system includes a fan nozzle to receive a fan flow from a fan disposed adjacent to an engine disposed above an airframe surface of the aircraft, a core nozzle disposed within the fan nozzle and receiving an engine core flow, and a pylon structure connected to the core nozzle and structurally attached with the airframe surface to secure the engine to the aircraft.

  4. Pseudo Aircraft Systems - A multi-aircraft simulation system for air traffic control research

    NASA Technical Reports Server (NTRS)

    Weske, Reid A.; Danek, George L.

    1993-01-01

    Pseudo Aircraft Systems (PAS) is a computerized flight dynamics and piloting system designed to provide a high fidelity multi-aircraft real-time simulation environment to support Air Traffic Control research. PAS is composed of three major software components that run on a network of computer workstations. Functionality is distributed among these components to allow the system to execute fast enough to support real-time operation. PAS workstations are linked by an Ethernet Local Area Network, and standard UNIX socket protocol is used for data transfer. Each component of PAS is controlled and operated using a custom designed Graphical User Interface. Each of these is composed of multiple windows, and many of the windows and sub-windows are used in several of the components. Aircraft models and piloting logic are sophisticated and realistic and provide complex maneuvering and navigational capabilities. PAS will continually be enhanced with new features and improved capabilities to support ongoing and future Air Traffic Control system development.

  5. Fault-tolerant electrical power system

    NASA Astrophysics Data System (ADS)

    Mehdi, Ishaque S.; Weimer, Joseph A.

    1987-10-01

    An electrical system that will meet the requirements of a 1990s two-engine fighter is being developed in the Fault-Tolerant Electrical Power System (FTEPS) program, sponsored by the AFWAL Aero Propulsion Laboratory. FTEPS will demonstrate the generation and distribution of fault-tolerant, reliable, electrical power required for future aircraft. The system incorporates MIL-STD-1750A digital processors and MIL-STD-1553B data buses for control and communications. Electrical power is distributed through electrical load management centers by means of solid-state power controllers for fault protection and individual load control. The system will provide uninterruptible power to flight-critical loads such as the flight control and mission computers with sealed lead-acid batteries. Primary power is provided by four 60 kVA variable speed constant frequency generators. Buildup and testing of the FTEPS demonstrator is expected to be complete by May 1988.

  6. The rotor systems research aircraft - A flying wind tunnel

    NASA Technical Reports Server (NTRS)

    Linden, A. W.; Hellyar, M. W.

    1974-01-01

    The Sikorsky Aircraft division of United Aircraft Corporation is constructing two uniquely designed Rotor Systems Research Aircraft (RSRA). These aircraft will be used through the 1980's to comparatively test many different types of rotors - articulated, hingeless, teetering, and gimballed, as well as advanced rotor concepts, such as reverse velocity and variable diameter rotors. The RSRA combines a new airframe with existing Sikorsky H-3 (S-61) dynamic components. A force measurement system is incorporated to permit accurate evaluation of significant rotor characteristics. Both rotor and fixed-wing control systems are provided, appropriately integrated for operation in the pure helicopter mode, compound helicopter mode, and fixed-wing mode. The RSRA is the first rotary wing aircraft designed with a crew escape system, including a pyrotechnic system to sever the main rotor blades.

  7. Pneumatic system structure for circulation control aircraft

    NASA Technical Reports Server (NTRS)

    Krauss, Timothy A. (Inventor); Roman, Stephan (Inventor); Beurer, Robert J. (Inventor)

    1986-01-01

    A plenum for a circulation control rotor aircraft which surrounds the rotor drive shaft (18) and is so constructed that the top (32), outer (38) and bottom (36) walls through compressed air is admitted are fixed to aircraft structure and the inner wall (34) through which air passes to rotor blades (14) rotates with the drive shaft and rotor blades.

  8. Smart camera system for aircraft and spacecraft

    NASA Astrophysics Data System (ADS)

    Delgado, Francisco J.; White, Janis; Abernathy, Michael F.

    2003-09-01

    This paper describes a new approach to situation awareness that combines video sensor technology and synthetic vision technology in a unique fashion to create a hybrid vision system. Our implementation of the technology, called "SmartCam3D" (SCS3D) has been flight tested by both NASA and the Department of Defense with excellent results. This paper details its development and flight test results. Windshields and windows add considerable weight and risk to vehicle design, and because of this, many future vehicles will employ a windowless cockpit design. This windowless cockpit design philosophy prompted us to look at what would be required to develop a system that provides crewmembers and operations personnel an appropriate level of situation awareness. The system created to date provides a real-time 3D perspective display that can be used during all-weather and visibility conditions. While the advantages of a synthetic vision only system are considerable, the major disadvantage of such a system is that it displays the synthetic scene created using "static" data acquired by an aircraft or satellite at some point in the past. The SCS3D system we are presenting in this paper is a hybrid synthetic vision system that fuses live video stream information with a computer generated synthetic scene. This hybrid system can display a dynamic, real-time scene of a region of interest, enriched by information from a synthetic environment system, see figure 1. The SCS3D system has been flight tested on several X-38 flight tests performed over the last several years and on an ARMY Unmanned Aerial Vehicle (UAV) ground control station earlier this year. Additional testing using an assortment of UAV ground control stations and UAV simulators from the Army and Air Force will be conducted later this year. We are also identifying other NASA programs that would benefit from the use of this technology.

  9. Smart Camera System for Aircraft and Spacecraft

    NASA Technical Reports Server (NTRS)

    Delgado, Frank; White, Janis; Abernathy, Michael F.

    2003-01-01

    This paper describes a new approach to situation awareness that combines video sensor technology and synthetic vision technology in a unique fashion to create a hybrid vision system. Our implementation of the technology, called "SmartCam3D" (SC3D) has been flight tested by both NASA and the Department of Defense with excellent results. This paper details its development and flight test results. Windshields and windows add considerable weight and risk to vehicle design, and because of this, many future vehicles will employ a windowless cockpit design. This windowless cockpit design philosophy prompted us to look at what would be required to develop a system that provides crewmembers and awareness. The system created to date provides a real-time operations personnel an appropriate level of situation 3D perspective display that can be used during all-weather and visibility conditions. While the advantages of a synthetic vision only system are considerable, the major disadvantage of such a system is that it displays the synthetic scene created using "static" data acquired by an aircraft or satellite at some point in the past. The SC3D system we are presenting in this paper is a hybrid synthetic vision system that fuses live video stream information with a computer generated synthetic scene. This hybrid system can display a dynamic, real-time scene of a region of interest, enriched by information from a synthetic environment system, see figure 1. The SC3D system has been flight tested on several X-38 flight tests performed over the last several years and on an ARMY Unmanned Aerial Vehicle (UAV) ground control station earlier this year. Additional testing using an assortment of UAV ground control stations and UAV simulators from the Army and Air Force will be conducted later this year.

  10. Retrieving Storm Electric Fields from Aircraft Field Mill Data. Part 1; Theory

    NASA Technical Reports Server (NTRS)

    Koshak, W. J.

    2006-01-01

    It is shown that the problem of retrieving storm electric fields from an aircraft instrumented with several electric field mill sensors can be expressed in terms of a standard Lagrange multiplier optimization problem. The method naturally removes aircraft charge from the retrieval process without having to use a high voltage stinger and linearly combined mill data values. It allows a variety of user-supplied physical constraints (the so-called side constraints in the theory of Lagrange multipliers) and also helps improve absolute calibration. Additionally, this paper introduces an alternate way of performing the absolute calibration of an aircraft that has some benefits over conventional analyses. It is accomplished by using the time derivatives of mill and pitch data for a pitch down maneuver performed at high (greater than 1 km) altitude. In Part II of this study, the above methods are tested and then applied to complete a full calibration of a Citation aircraft.

  11. Retrieving Storm Electric Fields From Aircraft Field Mill Data. Part I: Theory

    NASA Technical Reports Server (NTRS)

    Koshak, W. J.

    2005-01-01

    It is shown that the problem of retrieving storm electric fields from an aircraft instrumented with several electric field mill sensors can be expressed in terms of a standard Lagrange multiplier optimization problem. The method naturally removes aircraft charge from the retrieval process without having to use a high voltage stinger and linearly combined mill data values. It also allows a variety of user-supplied physical constraints (the so-called side constraints in the theory of Lagrange multipliers). Additionally, this paper introduces a novel way of performing the absolute calibration of an aircraft that has several benefits over conventional analyses. In the new approach, absolute calibration is completed by inspecting the time derivatives of mill and pitch data for a pitch down maneuver performed at high (greater than 1 km) altitude. In Part II of this study, the above methods are tested and then applied to complete a full calibration of a Citation aircraft.

  12. 78 FR 38076 - NASA Advisory Council; Aeronautics Committee; Unmanned Aircraft Systems Subcommittee; Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-25

    ... SPACE ADMINISTRATION NASA Advisory Council; Aeronautics Committee; Unmanned Aircraft Systems... Aeronautics and Space Administration announces a meeting of the Unmanned Aircraft Systems (UAS) Subcommittee... meeting includes the following topics: ] Review of NASA Unmanned Aircraft System (UAS) Integration...

  13. Automatic Aircraft Collision Avoidance System and Method

    NASA Technical Reports Server (NTRS)

    Skoog, Mark (Inventor); Hook, Loyd (Inventor); McWherter, Shaun (Inventor); Willhite, Jaimie (Inventor)

    2014-01-01

    The invention is a system and method of compressing a DTM to be used in an Auto-GCAS system using a semi-regular geometric compression algorithm. In general, the invention operates by first selecting the boundaries of the three dimensional map to be compressed and dividing the three dimensional map data into regular areas. Next, a type of free-edged, flat geometric surface is selected which will be used to approximate terrain data of the three dimensional map data. The flat geometric surface is used to approximate terrain data for each regular area. The approximations are checked to determine if they fall within selected tolerances. If the approximation for a specific regular area is within specified tolerance, the data is saved for that specific regular area. If the approximation for a specific area falls outside the specified tolerances, the regular area is divided and a flat geometric surface approximation is made for each of the divided areas. This process is recursively repeated until all of the regular areas are approximated by flat geometric surfaces. Finally, the compressed three dimensional map data is provided to the automatic ground collision system for an aircraft.

  14. A Future with Hybrid Electric Propulsion Systems: A NASA Perspective

    NASA Technical Reports Server (NTRS)

    DelRosario, Ruben

    2014-01-01

    The presentation highlights a NASA perspective on Hybrid Electric Propulsion Systems for aeronautical applications. Discussed are results from NASA Advance Concepts Study for Aircraft Entering service in 2030 and beyond and the potential use of hybrid electric propulsion systems as a potential solution to the requirements for energy efficiency and environmental compatibility. Current progress and notional potential NASA research plans are presented.

  15. Electrical system architecture

    DOEpatents

    Algrain, Marcelo C.; Johnson, Kris W.; Akasam, Sivaprasad; Hoff, Brian D.

    2008-07-15

    An electrical system for a vehicle includes a first power source generating a first voltage level, the first power source being in electrical communication with a first bus. A second power source generates a second voltage level greater than the first voltage level, the second power source being in electrical communication with a second bus. A starter generator may be configured to provide power to at least one of the first bus and the second bus, and at least one additional power source may be configured to provide power to at least one of the first bus and the second bus. The electrical system also includes at least one power consumer in electrical communication with the first bus and at least one power consumer in electrical communication with the second bus.

  16. Benefits of Hybrid-Electric Propulsion to Achieve 4x Increase in Cruise Efficiency for a VTOL Aircraft

    NASA Technical Reports Server (NTRS)

    Fredericks, William J.; Moore, Mark D.; Busan, Ronald C.

    2013-01-01

    Electric propulsion enables radical new vehicle concepts, particularly for Vertical Takeoff and Landing (VTOL) aircraft because of their significant mismatch between takeoff and cruise power conditions. However, electric propulsion does not merely provide the ability to normalize the power required across the phases of flight, in the way that automobiles also use hybrid electric technologies. The ability to distribute the thrust across the airframe, without mechanical complexity and with a scale-free propulsion system, is a new degree of freedom for aircraft designers. Electric propulsion is scale-free in terms of being able to achieve highly similar levels of motor power to weight and efficiency across a dramatic scaling range. Applying these combined principles of electric propulsion across a VTOL aircraft permits an improvement in aerodynamic efficiency that is approximately four times the state of the art of conventional helicopter configurations. Helicopters typically achieve a lift to drag ratio (L/D) of between 4 and 5, while the VTOL aircraft designed and developed in this research were designed to achieve an L/D of approximately 20. Fundamentally, the ability to eliminate the problem of advancing and retreating rotor blades is shown, without resorting to unacceptable prior solutions such as tail-sitters. This combination of concept and technology also enables a four times increase in range and endurance while maintaining the full VTOL and hover capability provided by a helicopter. Also important is the ability to achieve low disc-loading for low ground impingement velocities, low noise and hover power minimization (thus reducing energy consumption in VTOL phases). This combination of low noise and electric propulsion (i.e. zero emissions) will produce a much more community-friendly class of vehicles. This research provides a review of the concept brainstorming, configuration aerodynamic and mission analysis, as well as subscale prototype construction and

  17. Rotor systems research aircraft airplane configuration flight-test results

    NASA Technical Reports Server (NTRS)

    Painter, W. D.; Erickson, R. E.

    1984-01-01

    The rotor systems research aircraft (RSRA) has undergone ground and flight tests, primarily as a compound aircraft. The purpose was to train pilots and to check out and develop the design flight envelope. The preparation and flight test of the RSRA in the airplane, or fixed-wind, configuration are reviewed and the test results are discussed.

  18. Electric Field Profiles over Hurricanes, Tropical Cyclones, and Thunderstorms with an Instrumented ER-2 Aircraft

    NASA Technical Reports Server (NTRS)

    Mach, Doug M.; Blakeslee, Richard J.; Bateman, Monte G.; Bailey, Jeff C.

    2007-01-01

    Over the past several years, we have flown a set of calibrated electric field meters (FMs) on the NASA high altitude ER-2 aircraft over oceanic and landbased storms in a number of locations. These included tropical oceanic cyclones and hurricanes in the Caribbean and Atlantic ocean during the Third and Fourth Convection And Moisture EXperiment (CAMEX-3,1998; CAMEX-4, 2001), thunderstorms in Florida during the TExas FLorida UNderflight (TEFLUN, 1998) experiment, tropical thunderstorms in Brazil during the Tropical Rainfall Measuring Mission - Large Scale Biosphere-Atmosphere Experiment in Amazonia (TRMM LBA, 1999), and finally, hurricanes and tropical cyclones in the Caribbean and Western Pacific and thunderstorms in Central America during the Tropical Cloud Systems and Processes (TCSP, 2005) mission. Between these various missions we have well over 50 sorties that provide a unique insights on the different electrical environment, evolution and activity occurring in and around these various types of storms. In general, the electric fields over the tropical oceanic storms and hurricanes were less than a few kilovolts per meter at the ER-2 altitude, while the lightning rates were low. Land-based thunderstorms often produced high lightning activity and correspondingly higher electric fields.

  19. Systems integration studies for supersonic cruise aircraft

    NASA Technical Reports Server (NTRS)

    Mascitti, V. R.

    1975-01-01

    Technical progress in each of the disciplinary research areas affecting the design of supersonic cruise aircraft is discussed. The NASA AST/SCAR Program supported the integration of these technical advances into supersonic cruise aircraft configuration concepts. While the baseline concepts reflect differing design philosophy, all reflect a level of economic performance considerably above the current foreign aircraft as well as the former U.S. SST. Range-payload characteristics of the study configurating show significant improvement, while meeting environmental goals such as takeoff and landing noise and upper atmospheric pollution.

  20. Hawaii electric system reliability.

    SciTech Connect

    Silva Monroy, Cesar Augusto; Loose, Verne William

    2012-09-01

    This report addresses Hawaii electric system reliability issues; greater emphasis is placed on short-term reliability but resource adequacy is reviewed in reference to electric consumers' views of reliability %E2%80%9Cworth%E2%80%9D and the reserve capacity required to deliver that value. The report begins with a description of the Hawaii electric system to the extent permitted by publicly available data. Electrical engineering literature in the area of electric reliability is researched and briefly reviewed. North American Electric Reliability Corporation standards and measures for generation and transmission are reviewed and identified as to their appropriateness for various portions of the electric grid and for application in Hawaii. Analysis of frequency data supplied by the State of Hawaii Public Utilities Commission is presented together with comparison and contrast of performance of each of the systems for two years, 2010 and 2011. Literature tracing the development of reliability economics is reviewed and referenced. A method is explained for integrating system cost with outage cost to determine the optimal resource adequacy given customers' views of the value contributed by reliable electric supply. The report concludes with findings and recommendations for reliability in the State of Hawaii.

  1. Advanced Air Data Systems for Commercial Aircraft

    NASA Technical Reports Server (NTRS)

    2006-01-01

    It is possible to get a crude estimate of wind speed and direction while driving a car at night in the rain, with the motion of the raindrop reflections in the headlights providing clues about the wind. The clues are difficult to interpret, though, because of the relative motions of ground, car, air, and raindrops. More subtle interpretation is possible if the rain is replaced by fog, because the tiny droplets would follow the swirling currents of air around an illuminated object, like, for example, a walking pedestrian. Microscopic particles in the air (aerosols) are better for helping make assessments of the wind, and reflective air molecules are best of all, providing the most refined measurements. It takes a bright light to penetrate fog, so it is easy to understand how other factors, like replacing the headlights with the intensity of a searchlight, can be advantageous. This is the basic principle behind a lidar system. While a radar system transmits a pulse of radiofrequency energy and interprets the received reflections, a lidar system works in a similar fashion, substituting a near-optical laser pulse. The technique allows the measurement of relative positions and velocities between the transmitter and the air, which allows measurements of relative wind and of air temperature (because temperature is associated with high-frequency random motions on a molecular level). NASA, as well as the National Oceanic and Atmospheric Administration (NOAA), have interests in this advanced lidar technology, as much of their explorative research requires the ability to measure winds and turbulent regions within the atmosphere. Lidar also shows promise for providing warning of turbulent regions within the National Airspace System to allow commercial aircraft to avoid encounters with turbulence and thereby increase the safety of the traveling public. Both agencies currently employ lidar and optical sensing for a variety of weather-related research projects, such as analyzing

  2. Application of Active Controls Technology to Aircraft Ride Smoothing Systems

    NASA Technical Reports Server (NTRS)

    Lapins, Maris; Jacobson, Ira D.

    1975-01-01

    A critical review of past efforts in the design and testing of ride smoothing and gust alleviation systems is presented. Design trade-offs involving sensor types, choice of feedback loops, human comfort and aircraft handling-qualities criteria are discussed. Synthesis of a system designed to employ direct-lift and side-force producing surfaces is reported. Two STOL-class aircraft and an executive transport are considered. Theoretically-predicted system performance is compared with hybrid simulation and flight test data. Pilot opinion rating, pilot workload, and passenger comfort rating data for the basic and augmented aircraft are included.

  3. Application of active controls technology to aircraft bide smoothing systems

    NASA Technical Reports Server (NTRS)

    Lapins, M.; Jacobson, I. D.

    1975-01-01

    A critical review of past efforts in the design and testing of ride smoothing and gust alleviation systems is presented. Design trade offs involving sensor types, choice of feedback loops, human comfort, and aircraft handling-qualities criteria are discussed. Synthesis of a system designed to employ direct-lift and side-force producing surfaces is reported. Two STOL aircraft and an executive transport are considered. Theoretically predicted system performance is compared with hybrid simulation and flight test data. Pilot opinion rating, pilot workload, and passenger comfort rating data for the basic and augmented aircraft are included.

  4. Atmospheric Observations from Unmanned Aircraft Systems

    NASA Technical Reports Server (NTRS)

    Newman, Paul A.

    2008-01-01

    Unmanned Aircraft Systems (UASs) provide a new and exciting avenue for atmospheric observations. NASA has a number of UASs. Amongst these are the Ikhana (24 hrs., 7000 km), the Altair (120 hrs., 6500 km), the Aerosonde (30 hrs., 3000 km), and the Global Hawk (30 hrs., 22,000 km). This presentation provides a brief history of UASs which is followed by a description of their capabilities. The presentation concludes by describing an example mission - the UAS Aura Validation Experiment (UAS-AVE). This mission will be flown on the NASA Global Hawk in the Spring/Summer of 2009. The goals fo the mission are to: 1) provide Aura validation observations, 2) sample the break up of the Arctic polar vortex, 3) observed cross-Pacific transport of aerosols and pollutants such as ozone, and 4) sample intense water advective events that impact the U.S. west coast (atmospheric rivers). Because of their range and duration, UASs provide new and exciting opportunities for atmospheric science.

  5. Electric turbocompound control system

    DOEpatents

    Algrain, Marcelo C.

    2007-02-13

    Turbocompound systems can be used to affect engine operation using the energy in exhaust gas that is driving the available turbocharger. A first electrical device acts as a generator in response to turbocharger rotation. A second electrical device acts as a motor to put mechanical power into the engine, typically at the crankshaft. Apparatus, systems, steps, and methods are described to control the generator and motor operations to control the amount of power being recovered. This can control engine operation closer to desirable parameters for given engine-related operating conditions compared to actual. The electrical devices can also operate in "reverse," going between motor and generator functions. This permits the electrical device associated with the crankshaft to drive the electrical device associated with the turbocharger as a motor, overcoming deficient engine operating conditions such as associated with turbocharger lag.

  6. Remote Sensing of Electric Atmospheric Field Produced by Storm Cloud With an Instrumented Aircraft

    NASA Astrophysics Data System (ADS)

    Laroche, P. A.; Delannoy, A.; Blanchet, P.; Lalande, P.

    2010-12-01

    Sensing the 3 components of the atmospheric field is an efficient way to diagnose the electrification of convective cloud. This is currently done by rocket (Win and Moore 1971), balloon (Stolzenburg et al. 2007) and instrumented aircraft (Win 1993, Koshak et al. 2006). Intra cloud measurement can help to evidence electrification process (Sonnenfeld et al. 2006) or revealed local charged region in CB anvil (Dye et al. 2007). In 2010 a Falcon 20 jet aircraft has been instrumented to retrieve the value of electrostatic field in the vicinity of convective cloud. Instrumentation consists in 8 field mill mounted flush on aircraft surface. Each sensor delivers a linear measurement of the field at the surface of the aircraft from 10 V/m up to 80 kV/m. Calibration of the atmospheric electric field retrieving method has been done by using Koshak’s method and computation on a numerical meshing of the aircraft. With the present setting, the field mill network saturation occurs for an atmospheric field magnitude close to 12 kV/m. Several flights were performed close to and inside deep convective cloud at altitude ranging between 1500 and 6000 m AMSL. We present and discuss the observations obtained during this field experiment. Horizontal Atmospheric Electric Field along the trajectory of the aircraft

  7. Method and System for Active Noise Control of Tiltrotor Aircraft

    NASA Technical Reports Server (NTRS)

    Betzina, Mark D. (Inventor); Nguyen, Khanh Q. (Inventor)

    2003-01-01

    Methods and systems for reducing noise generated by rotating blades of a tiltrotor aircraft. A rotor-blade pitch angle associated with the tiltrotor aircraft can be controlled utilizing a swashplate connected to rotating blades of the tiltrotor aircraft. One or more Higher Harmonic Control (HHC) signals can be transmitted and input to a swashplate control actuator associated with the swashplate. A particular blade pitch oscillation (e.g., four cycles per revolution) is there-after produced in a rotating frame of reference associated with the rotating blades in response to input of an HHC signal to the swashplate control actuator associated with the swashplate to thereby reduce noise associated with the rotating blades of the tiltrotor aircraft. The HHC signal can be transmitted and input to the swashplate control actuator to reduce noise of the tiltrotor aircraft in response to a user input utilizing an open-loop configuration.

  8. The Pilatus unmanned aircraft system for lower atmospheric research

    NASA Astrophysics Data System (ADS)

    de Boer, Gijs; Palo, Scott; Argrow, Brian; LoDolce, Gabriel; Mack, James; Gao, Ru-Shan; Telg, Hagen; Trussel, Cameron; Fromm, Joshua; Long, Charles N.; Bland, Geoff; Maslanik, James; Schmid, Beat; Hock, Terry

    2016-04-01

    This paper presents details of the University of Colorado (CU) "Pilatus" unmanned research aircraft, assembled to provide measurements of aerosols, radiation and thermodynamics in the lower troposphere. This aircraft has a wingspan of 3.2 m and a maximum take-off weight of 25 kg, and it is powered by an electric motor to reduce engine exhaust and concerns about carburetor icing. It carries instrumentation to make measurements of broadband up- and downwelling shortwave and longwave radiation, aerosol particle size distribution, atmospheric temperature, relative humidity and pressure and to collect video of flights for subsequent analysis of atmospheric conditions during flight. In order to make the shortwave radiation measurements, care was taken to carefully position a high-quality compact inertial measurement unit (IMU) and characterize the attitude of the aircraft and its orientation to the upward-looking radiation sensor. Using measurements from both of these sensors, a correction is applied to the raw radiometer measurements to correct for aircraft attitude and sensor tilt relative to the sun. The data acquisition system was designed from scratch based on a set of key driving requirements to accommodate the variety of sensors deployed. Initial test flights completed in Colorado provide promising results with measurements from the radiation sensors agreeing with those from a nearby surface site. Additionally, estimates of surface albedo from onboard sensors were consistent with local surface conditions, including melting snow and bright runway surface. Aerosol size distributions collected are internally consistent and have previously been shown to agree well with larger, surface-based instrumentation. Finally the atmospheric state measurements evolve as expected, with the near-surface atmosphere warming over time as the day goes on, and the atmospheric relative humidity decreasing with increased temperature. No directional bias on measured temperature, as might

  9. The pilatus unmanned aircraft system for lower atmospheric research

    NASA Astrophysics Data System (ADS)

    de Boer, G.; Palo, S.; Argrow, B.; LoDolce, G.; Mack, J.; Gao, R.-S.; Telg, H.; Trussel, C.; Fromm, J.; Long, C. N.; Bland, G.; Maslanik, J.; Schmid, B.; Hock, T.

    2015-11-01

    This paper presents details of the University of Colorado (CU) Pilatus unmanned research aircraft, assembled to provide measurements of aerosols, radiation and thermodynamics in the lower troposphere. This aircraft has a wingspan of 3.2 m and a maximum take off weight of 25 kg and is powered by an electric motor to reduce engine exhaust and concerns about carburetor icing. It carries instrumentation to make measurements of broadband up- and downwelling shortwave and longwave radiation, aerosol particle size distribution, atmospheric temperature, relative humidity and pressure and to collect video of flights for subsequent analysis of atmospheric conditions during flight. In order to make the shortwave radiation measurements, care was taken to carefully position a high-quality compact inertial measurement unit (IMU) and characterize the attitude of the aircraft and it's orientation to the upward looking radiation sensor. Using measurements from both of these sensors, a correction is applied to the raw radiometer measurements to correct for aircraft attitude and sensor tilt relative to the sun. The data acquisition system was designed from scratch based on a set of key driving requirements to accommodate the variety of sensors deployed. Initial test flights completed in Colorado provide promising results with measurements from the radiation sensors agreeing with those from a nearby surface site. Additionally, estimates of surface albedo from onboard sensors were consistent with local surface conditions, including melting snow and bright runway surface. Aerosol size distributions collected are internally consistent and have previously been shown to agree well with larger, surface-based instrumentation. Finally the atmospheric state measurements evolve as expected, with the near-surface atmosphere warming over time as the day goes on, and the atmospheric relative humidity decreasing with increased temperature. No directional bias on measured temperature, as might be

  10. Electric micropropulsion systems

    NASA Astrophysics Data System (ADS)

    Wright, W. P.; Ferrer, P.

    2015-04-01

    With the development of microspacecraft, the field of electrical micropropulsion is a rapidly expanding discipline. New ideas are being explored constantly and a review of the current state of technological development in the field will be useful. This review deals with electrostatic and electromagnetic micropropulsion systems that are either miniaturization attempts of existing technologies or novel systems in their own right. A brief discussion of the development of microspacecraft and a general overview of the types of micropropulsion are given. The essential mechanism of operation of each electrical micropropulsion system is described and recent progress in the development of these systems is explored, giving latest available data of their performance parameters.

  11. Inerting Aircraft Fuel Systems Using Exhaust Gases

    NASA Technical Reports Server (NTRS)

    Hehemann, David G.

    2002-01-01

    Our purpose in this proposal was to determine the feasibility of using carbon dioxide, possibly obtained from aircraft exhaust gases as a substance to inert the fuel contained in fuel tanks aboard aircraft. To do this, we decided to look at the effects carbon dioxide has upon commercial Jet-A aircraft fuel. In particular, we looked at the solubility of CO2 in Jet-A fuel, the pumpability of CO2-saturated Jet-A fuel, the flashpoint of Jet-A fuel under various mixtures of air and CO2, the static outgassing of CO2-Saturated Jet-A fuel and the dynamic outgassing of Jet-A fuel during pumping of Jet-A fuel.

  12. Advanced fuel system technology for utilizing broadened property aircraft fuels

    NASA Technical Reports Server (NTRS)

    Reck, G. M.

    1980-01-01

    Possible changes in fuel properties are identified based on current trends and projections. The effect of those changes with respect to the aircraft fuel system are examined and some technological approaches to utilizing those fuels are described.

  13. Parametric study of transport aircraft systems cost and weight

    NASA Technical Reports Server (NTRS)

    Beltramo, M. N.; Trapp, D. L.; Kimoto, B. W.; Marsh, D. P.

    1977-01-01

    The results of a NASA study to develop production cost estimating relationships (CERs) and weight estimating relationships (WERs) for commercial and military transport aircraft at the system level are presented. The systems considered correspond to the standard weight groups defined in Military Standard 1374 and are listed. These systems make up a complete aircraft exclusive of engines. The CER for each system (or CERs in several cases) utilize weight as the key parameter. Weights may be determined from detailed weight statements, if available, or by using the WERs developed, which are based on technical and performance characteristics generally available during preliminary design. The CERs that were developed provide a very useful tool for making preliminary estimates of the production cost of an aircraft. Likewise, the WERs provide a very useful tool for making preliminary estimates of the weight of aircraft based on conceptual design information.

  14. Aircraft systems design studies employing advanced transport technologies

    NASA Technical Reports Server (NTRS)

    Downie, B.; Pearce, C.; Quartero, C.; Taylor, A.

    1972-01-01

    System and design integration studies are presented to define and assess the application of the advanced technology most likely to result in a superior next generation, high subsonic/sonic conventional takeoff and landing transport aircraft system. It is concluded that the new technologies can be directed toward the achievement of improved economy and performance. These benefits may be used to compensate for the penalties associated with reduced noise requirements anticipated to make future aircraft ecologically acceptable.

  15. Aircraft Electrical Repairman, 2-1. Military Curriculum Materials for Vocational and Technical Education.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This three-volume textbook and three student workbooks for a secondary-postsecondary level course in aircraft electrical repair comprise one of a number of military-developed curriculum packages selected for adaptation to vocational instruction and curriculum development in a civilian setting. The purpose stated for the individualized, self-paced…

  16. Neural networks for aircraft system identification

    NASA Technical Reports Server (NTRS)

    Linse, Dennis J.

    1991-01-01

    Artificial neural networks offer some interesting possibilities for use in control. Our current research is on the use of neural networks on an aircraft model. The model can then be used in a nonlinear control scheme. The effectiveness of network training is demonstrated.

  17. Preliminary Considerations for Classifying Hazards of Unmanned Aircraft Systems

    NASA Technical Reports Server (NTRS)

    Hayhurst, Kelly J.; Maddalon, Jeffrey M.; Miner, Paul S.; Szatkowski, George N.; Ulrey, Michael L.; DeWalt, Michael P.; Spitzer, Cary R.

    2007-01-01

    The use of unmanned aircraft in national airspace has been characterized as the next great step forward in the evolution of civil aviation. To make routine and safe operation of these aircraft a reality, a number of technological and regulatory challenges must be overcome. This report discusses some of the regulatory challenges with respect to deriving safety and reliability requirements for unmanned aircraft. In particular, definitions of hazards and their classification are discussed and applied to a preliminary functional hazard assessment of a generic unmanned system.

  18. Small Aircraft Transportation System, Higher Volume Operations Concept: Normal Operations

    NASA Technical Reports Server (NTRS)

    Abbott, Terence S.; Jones, Kenneth M.; Consiglio, Maria C.; Williams, Daniel M.; Adams, Catherine A.

    2004-01-01

    This document defines the Small Aircraft Transportation System (SATS), Higher Volume Operations (HVO) concept for normal conditions. In this concept, a block of airspace would be established around designated non-towered, non-radar airports during periods of poor weather. Within this new airspace, pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft. Using onboard equipment and procedures, they would then approach and land at the airport. Departures would be handled in a similar fashion. The details for this operational concept are provided in this document.

  19. Overview of Propulsion Systems for a Mars Aircraft

    NASA Technical Reports Server (NTRS)

    Colozza, Anthony J.; Miller, Christopher J.; Reed, Brian D.; Kohout, Lisa L.; Loyselle, Patricia L.

    2001-01-01

    The capabilities and performance of an aircraft depends greatly on the ability of the propulsion system to provide thrust. Since the beginning of powered flight, performance has increased in step with advancements in aircraft propulsion systems. These advances in technology from combustion engines to jets and rockets have enabled aircraft to exploit our atmospheric environment and fly at altitudes near the Earth's surface to near orbit at speeds ranging from hovering to several times the speed of sound. One of the main advantages of our atmosphere for these propulsion systems is the availability of oxygen. Getting oxygen basically "free" from the atmosphere dramatically increases the performance and capabilities of an aircraft. This is one of the reasons our present-day aircraft can perform such a wide range of tasks. But this advantage is limited to Earth; if we want to fly an aircraft on another planetary body, such as Mars, we will either have to carry our own source of oxygen or use a propulsion system that does not require it. The Mars atmosphere, composed mainly of carbon dioxide, is very thin. Because of this low atmospheric density, an aircraft flying on Mars will most likely be operating, in aerodynamical terms, within a very low Reynolds number regime. Also, the speed of sound within the Martian environment is approximately 20 percent less than it is on Earth. The reduction in the speed of sound plays an important role in the aerodynamic performance of both the aircraft itself and the components of the propulsion system, such as the propeller. This low Reynolds number-high Mach number flight regime is a unique flight environment that is very rarely encountered here on Earth.

  20. Flying qualities and control system characteristics for superaugmented aircraft

    NASA Technical Reports Server (NTRS)

    Myers, T. T.; Mcruer, D. T.; Johnston, D. E.

    1984-01-01

    Aircraft-alone dynamics and superaugmented control system fundamental regulatory properties including stability and regulatory responses of the basic closed-loop systems; fundamental high and low frequency margins and governing factors; and sensitivity to aircraft and controller parameters are addressed. Alternative FCS mechanizations, and mechanizational side effects are also discussed. An overview of flying qualities considerations encompasses general pilot operations as a controller in unattended, intermittent and trim, and full-attention regulatory or command control; effective vehicle primary and secondary response properties to pilot inputs and disturbances; pilot control architectural possibilities; and comparison of superaugmented and conventional aircraft path responses for different forms of pilot control. Results of a simple experimental investigation into pilot dynamic behavior in attitude control of superaugmented aircraft configurations with high frequency time laps and time delays are presented.

  1. Systems study of transport aircraft incorporating advanced aluminum alloys

    NASA Technical Reports Server (NTRS)

    Sakata, I. F.

    1982-01-01

    A study was performed to quantify the potential benefits of utilizing advanced aluminum alloys in commercial transport aircraft and to define the effort necessary to develop fully the alloys to a viable commercial production capability. The comprehensive investigation (1) established realistic advanced aluminum alloy property goals to maximize aircraft systems effectiveness (2) identified performance and economic benefits of incorporating the advanced alloy in future advanced technology commercial aircraft designs (3) provided a recommended plan for development and integration of the alloys into commercial aircraft production (4) provided an indication of the timing and investigation required by the metal producing industry to support the projected market and (5) evaluate application of advanced aluminum alloys to other aerospace and transit systems as a secondary objective. The results of the investigation provided a roadmap and identified key issues requiring attention in an advanced aluminum alloy and applications technology development program.

  2. Evaluation Of An Aircraft-Collision-Avoidance System

    NASA Technical Reports Server (NTRS)

    Chappell, Sheryl L.; Billings, Charles E.; Olsen, M. Christine; Scott, Barry C.; Tuttell, Robert J.; Kozon, Thomas E.

    1990-01-01

    Report describes study of pilots' use of traffic alert and collision-avoidance system (TCAS II) in simulated airplane flights. Gives alert by light and sound when another aircraft within 40 s of passing very closely. If other aircraft still poses threat 15 to 20 s later, TCAS II advises pilot to maneuver vertically or to continue on same flightpath but alter rate of ascent or descent. Report describes methodology, summarizes results, and presents conclusions.

  3. Experimental investigations of thrust vectoring systems for VTOL aircraft

    NASA Technical Reports Server (NTRS)

    Rolls, L. S.; Aoyagi, K.

    1977-01-01

    This paper presents a summary of two technology programs sponsored by NASA to investigate the characteristics of two thrust vectoring schemes for V/STOL aircraft. The operational capability of the VTOL aircraft is dependent on maximum utilization of the installed thrust in both the cruise and powered lift modes of flight. An effective thrust vectoring system on the cruise propulsion unit is therefore essential to provide maximum payload in hover and STOL plus minimum specific fuel consumption in loiter and cruise. Introducing a high by-pass ratio fan system, augmenting the gas generator thrust, as the propulsion system for VTOL aircraft places increased significance on the performance of the relatively short coupled thrust vectoring systems. The two programs discussed herein include both large-scale and small-scale tests of a vectoring hood system with a vented, internal-lip and swivel nozzle systems. These tests indicated that a satisfactory thrust vectoring system can be developed.

  4. Computer simulation of aircraft motions and propulsion system dynamics for the YF-12 aircraft at supersonic cruise conditions

    NASA Technical Reports Server (NTRS)

    Brown, S. C.

    1973-01-01

    A computer simulation of the YF-12 aircraft motions and propulsion system dynamics is presented. The propulsion system was represented in sufficient detail so that interactions between aircraft motions and the propulsion system dynamics could be investigated. Six degree-of-freedom aircraft motions together with the three-axis stability augmentation system were represented. The mixed compression inlets and their controls were represented in the started mode for a range of flow conditions up to the inlet unstart boundary. Effects of inlet moving geometry on aircraft forces and movements as well as effects of aircraft motions on the inlet behavior were simulated. The engines, which are straight subjects, were represented in the afterburning mode, with effects of changes in aircraft flight conditions included. The simulation was capable of operating in real time.

  5. Some wear studies on aircraft brake systems

    NASA Technical Reports Server (NTRS)

    Ho, T. L.

    1975-01-01

    An initial investigation of worn surfaces in friction pads and steel rotors used in current aircraft brakes was carried out using electron microprobe and X-ray diffraction analysis. It consists of the topographical study and the analysis of chemical element distribution. Based upon this initial examination, two approaches, microscopic and macroscopic have been conducted to interpret and formulate the wear mechanism of the aircraft brake materials. Microscopically, the wear particles were examined. The initiation and growth of surface cracks and the oxidation were emphasized in this investigation. Macroscopically, it has been found that, for the current copper based brake material sliding against 17-22 AS steel in a caliper brake, the surface temperature raised due to frictional heat is nonlinearly proportional to the load applied and slide time with speed at 1750 rpm. The wear of brake materials is then proportional to this temperature and is also a function of the melting temperature for copper.

  6. System identification methods for aircraft flight control development and validation

    NASA Technical Reports Server (NTRS)

    Tischler, Mark B.

    1995-01-01

    System-identification methods compose a mathematical model, or series of models, from measurements of inputs and outputs of dynamic systems. The extracted models allow the characterization of the response of the overall aircraft or component subsystem behavior, such as actuators and on-board signal processing algorithms. This paper discusses the use of frequency-domain system-identification methods for the development and integration of aircraft flight-control systems. The extraction and analysis of models of varying complexity from nonparametric frequency-responses to transfer-functions and high-order state-space representations is illustrated using the Comprehensive Identification from FrEquency Responses (CIFER) system-identification facility. Results are presented for test data of numerous flight and simulation programs at the Ames Research Center including rotorcraft, fixed-wing aircraft, advanced short takeoff and vertical landing (ASTOVL), vertical/short takeoff and landing (V/STOL), tiltrotor aircraft, and rotor experiments in the wind tunnel. Excellent system characterization and dynamic response prediction is achieved for this wide class of systems. Examples illustrate the role of system-identification technology in providing an integrated flow of dynamic response data around the entire life-cycle of aircraft development from initial specifications, through simulation and bench testing, and into flight-test optimization.

  7. Estimating electric field enhancement factors on an aircraft utilizing a small scale model: A method evaluation

    NASA Technical Reports Server (NTRS)

    Easterbrook, Calvin C.; Rudolph, Terence; Easterbrook, Kevin

    1988-01-01

    A method for obtaining field enhancement factors at specific points on an aircraft utilizing a small scale model was evaluated by measuring several canonical shapes. Comparison of the form factors obtained by analytical means with measurements indicate that the experimental method has serious flaws. Errors of 200 to 300 percent were found between analytical values and measured values. As a result of the study, the analytical method is not recommended for calibration of field meters located on aircraft, and should not be relied upon in any application where the local spatial derivatives of the electric field on the model are large over the dimensions of the sensing probe.

  8. A test technique for measuring lightning-induced voltages on aircraft electrical circuits

    NASA Technical Reports Server (NTRS)

    Walko, L. C.

    1974-01-01

    The development of a test technique used for the measurement of lightning-induced voltages in the electrical circuits of a complete aircraft is described. The resultant technique utilizes a portable device known as a transient analyzer capable of generating unidirectional current impulses similar to lightning current surges, but at a lower current level. A linear relationship between the magnitude of lightning current and the magnitude of induced voltage permitted the scaling up of measured induced values to full threat levels. The test technique was found to be practical when used on a complete aircraft.

  9. Project ADIOS: Aircraft Deployable Ice Observation System

    NASA Astrophysics Data System (ADS)

    Gudmundsson, G. H.

    2013-12-01

    Regions of the Antarctic that are of scientific interest are often too heavily crevassed to enable a plane to land, or permit safe access from a field camp. We have developed an alternative strategy for instrumenting these regions: a sensor that can be dropped from an overflying aircraft. Existing aircraft deployable sensors are not suitable for long term operations in areas where snow accumulates, as they are quickly buried. We have overcome this problem by shaping the sensor like an aerodynamic mast with fins and a small parachute. After being released from the aircraft, the sensor accelerates to 42m/s and stabilizes during a 10s descent. On impact with the snow surface the sensor package buries itself to a depth of 1m then uses the large surface area of the fins to stop it burying further. This leaves a 1.5m mast protruding high above the snow surface to ensure a long operating life. The high impact kinetic energy and robust fin braking mechanism ensure that the design works in both soft and hard snow. Over the past two years we have developed and tested our design with a series of aircraft and wind tunnel tests. Last season we used this deployment strategy to successfully install a network of 31 single band GPS sensors in regions where crevassing has previously prevented science operations: Pine Island Glacier, West Antarctica, and Scar Inlet, Antarctic Peninsula. This season we intend to expand on this network by deploying a further 25 single and dual band GPS sensors on Thwaites Glacier, West Antarctica.

  10. Study of aircraft in intraurban transportation systems, volume 1

    NASA Technical Reports Server (NTRS)

    Stout, E. G.; Kesling, P. H.; Matteson, H. C.; Sherwood, D. E.; Tuck, W. R., Jr.; Vaughn, L. A.

    1971-01-01

    An analysis of an effective short range, high density computer transportation system for intraurban systems is presented. The seven county Detroit, Michigan, metropolitan area, was chosen as the scenario for the analysis. The study consisted of an analysis and forecast of the Detroit market through 1985, a parametric analysis of appropriate short haul aircraft concepts and associated ground systems, and a preliminary overall economic analysis of a simplified total system designed to evaluate the candidate vehicles and select the most promising VTOL and STOL aircraft. Data are also included on the impact of advanced technology on the system, the sensitivity of mission performance to changes in aircraft characteristics and system operations, and identification of key problem areas that may be improved by additional research. The approach, logic, and computer models used are adaptable to other intraurban or interurban areas.

  11. The Automated Aircraft Rework System (AARS): A system integration approach

    NASA Technical Reports Server (NTRS)

    Benoit, Michael J.

    1994-01-01

    The Mercer Engineering Research Center (MERC), under contract to the United States Air Force (USAF) since 1989, has been actively involved in providing the Warner Robins Air Logistics Center (WR-ALC) with a robotic workcell designed to perform rework automated defastening and hole location/transfer operations on F-15 wings. This paper describes the activities required to develop and implement this workcell, known as the Automated Aircraft Rework System (AARS). AARS is scheduled to be completely installed and in operation at WR-ALC by September 1994.

  12. US electric power system reliability

    NASA Astrophysics Data System (ADS)

    Electric energy supply, transmission and distribution systems are investigated in order to determine priorities for legislation. The status and the outlook for electric power reliability are discussed.

  13. Solar electric systems

    SciTech Connect

    Warfield, G.

    1984-01-01

    Electricity from solar sources is the subject. The state-of-the-art of photovoltaics, wind energy and solar thermal electric systems is presented and also a broad range of solar energy activities throughout the Arab world is covered. Contents, abridged: Solar radiation fundamentals. Basic theory solar cells. Solar thermal power plants. Solar energy activities at the scientific research council in Iraq. Solar energy program at Kuwait Institute for Scientific Research. Prospects of solar energy for Egypt. Non-conventional energy in Syria. Wind and solar energies in Sudan. Index.

  14. Personal Electronic Devices and Their Interference with Aircraft Systems

    NASA Technical Reports Server (NTRS)

    Ross, Elden; Ely, Jay J. (Technical Monitor)

    2001-01-01

    A compilation of data on personal electronic devices (PEDs) attributed to having created anomalies with aircraft systems. Charts and tables display 14 years of incidents reported by pilots to the Aviation Safety Reporting System (ASRS). Affected systems, incident severity, sources of anomaly detection, and the most frequently identified PEDs are some of the more significant data. Several reports contain incidents of aircraft off course when all systems indicated on course and of critical events that occurred during landings and takeoffs. Additionally, PEDs that should receive priority in testing are identified.

  15. Solar Electric System

    NASA Technical Reports Server (NTRS)

    1987-01-01

    Heat Pipe Technology, Inc. undertook the development of a PV system that could bring solar electricity to the individual home at reasonable cost. His system employs high efficiency PV modules plus a set of polished reflectors that concentrate the solar energy and enhance the output of the modules. Dinh incorporated a sun tracking system derived from space tracking technology. It automatically follows the sun throughout the day and turns the modules so that they get maximum exposure to the solar radiation, further enhancing the system efficiency.

  16. Lightning effects on aircraft

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Direct and indirect effects of lightning on aircraft were examined in relation to aircraft design. Specific trends in design leading to more frequent lightning strikes were individually investigated. These trends included the increasing use of miniaturized, solid state components in aircraft electronics and electric power systems. A second trend studied was the increasing use of reinforced plastics and other nonconducting materials in place of aluminum skins, a practice that reduces the electromagnetic shielding furnished by a conductive skin.

  17. Fire blocking systems for aircraft seat cushions

    NASA Technical Reports Server (NTRS)

    Parker, J. A.; Kourtides, D. A. (Inventor)

    1984-01-01

    A configuration and method for reducing the flammability of bodies of organic materials that thermally decompose to give flammable gases comprises covering the body with a flexible matrix that catalytically cracks the flammable gases to less flammable species. Optionally, the matrix is covered with a gas impermeable outer layer. In a preferred embodiment, the invention takes the form of an aircraft seat in which the body is a poly(urethane) seat cushion, the matrix is an aramid fabric or felt and the outer layer is an aluminum film.

  18. Subsonic Ultra Green Aircraft Research: Phase 2. Volume 2; Hybrid Electric Design Exploration

    NASA Technical Reports Server (NTRS)

    Bradley, Marty K.; Droney, Christopher K.

    2015-01-01

    This report summarizes the hybrid electric concept design, analysis, and modeling work accomplished by the Boeing Subsonic Ultra Green Aircraft Research (SUGAR) team, consisting of Boeing Research and Technology, Boeing Commercial Airplanes, General Electric, and Georgia Tech.Performance and sizing tasks were conducted for hybrid electric versions of a conventional tube-and-wing aircraft and a hybrid wing body. The high wing Truss Braced Wing (TBW) SUGAR Volt was updated based on results from the TBW work (documented separately) and new engine performance models. Energy cost and acoustic analyses were conducted and technology roadmaps were updated for hybrid electric and battery technology. NOx emissions were calculated for landing and takeoff (LTO) and cruise. NPSS models were developed for hybrid electric components and tested using an integrated analysis of superconducting and non-superconducting hybrid electric engines. The hybrid electric SUGAR Volt was shown to produce significant emissions and fuel burn reductions beyond those achieved by the conventionally powered SUGAR High and was able to meet the NASA goals for fuel burn. Total energy utilization was not decreased but reduced energy cost can be achieved for some scenarios. The team was not able to identify a technology development path to meet NASA's noise goals

  19. Aircraft Icing Weather Data Reporting and Dissemination System

    NASA Technical Reports Server (NTRS)

    Bass, Ellen J.; Minsk, Brian; Lindholm, Tenny; Politovich, Marcia; Reehorst, Andrew (Technical Monitor)

    2002-01-01

    The long-term operational concept of this research is to develop an onboard aircraft system that assesses and reports atmospheric icing conditions automatically and in a timely manner in order to improve aviation safety and the efficiency of aircraft operations via improved real-time and forecast weather products. The idea is to use current measurement capabilities on aircraft equipped with icing sensors and in-flight data communication technologies as a reporting source. Without requiring expensive avionics upgrades, aircraft data must be processed and available for downlink. Ideally, the data from multiple aircraft can then be integrated (along with other real-time and modeled data) on the ground such that aviation-centered icing hazard metrics for volumes of airspace can be assessed. As the effect of icing on different aircraft types can vary, the information should be displayed in meaningful ways such that multiple types of users can understand the information. That is, information must be presented in a manner to allow users to understand the icing conditions with respect to individual concerns and aircraft capabilities. This research provides progress toward this operational concept by: identifying an aircraft platform capable of digitally capturing, processing, and downlinking icing data; identifying the required in situ icing data processing; investigating the requirements for routing the icing data for use by weather products; developing an icing case study in order to gain insight into major air carrier needs; developing and prototyping icing display concepts based on the National Center for Atmospheric Research's existing diagnostic and forecast experimental icing products; and conducting a usability study for the prototyped icing display concepts.

  20. NEMP Qualification of Electrically Simple Equipment on Aircraft via Analysis

    NASA Astrophysics Data System (ADS)

    Ockerse, J.; Flessa, C.

    2012-05-01

    The purpose of this paper is to demonstrate a theoretical analysis method for analysing the NEMP (Nuclear Electromagnetic Pulse) qualification status of electrically simple equipment or devices. (e.g., switches, actuators, sensors, etc.) The method is transparent to the certification authorities. This is in order to release them from the (costly) requirement for actual NEMP testing of these parts. This work is based on the experience gained in the successful certification of an advanced, all-carbon- fibre-composite (CFC) military helicopter. The method has been validated by testing.

  1. Sun sensing guidance system for high altitude aircraft

    NASA Technical Reports Server (NTRS)

    Reed, R. D. (Principal Investigator)

    1982-01-01

    A sun sensing guidance system for high altitude aircraft is described. The system is characterized by a disk shaped body mounted for rotation aboard the aircraft in exposed relation to solar radiation. The system also has a plurality of mutually isolated chambers; each chamber being characterized by an opening having a photosensor disposed therein and arranged in facing relation with the opening for receiving incident solar radiation and responsively providing a voltage output. Photosensors are connected in paired relation through a bridge circuit for providing heading error signals in response to detected imbalances in intensities of solar radiation.

  2. An efficient navigation-control system for small unmanned aircraft

    NASA Astrophysics Data System (ADS)

    Girwar-Nath, Jonathan Alejandro

    Unmanned Aerial Vehicles have been research in the past decade for a broad range of tasks and application domains such as search and rescue, reconnaissance, traffic control, pipe line inspections, surveillance, border patrol, and communication bridging. This work describes the design and implementation of a lightweight Commercial-Off-The-Shelf (COTS) semi-autonomous Fixed-Wing Unmanned Aerial Vehicle (UAV). Presented here is a methodology for System Identification utilizing the Box-Jenkins model estimator on recorded flight data to characterize the system and develop a mathematical model of the aircraft. Additionally, a novel microprocessor, the XMOS, is utilized to navigate and maneuver the aircraft utilizing a PD control system. In this thesis is a description of the aircraft and the sensor suite utilized, as well as the flight data and supporting videos for the benefit of the UAV research community.

  3. Flight Testing the Rotor Systems Research Aircraft (RSRA)

    NASA Technical Reports Server (NTRS)

    Hall, G. W.; Merrill, R. K.

    1983-01-01

    In the late 1960s, efforts to advance the state-of-the-art in rotor systems technology indicated a significant gap existed between our ability to accurately predict the characteristics of a complex rotor system and the results obtained through flight verification. Even full scale wind tunnel efforts proved inaccurate because of the complex nature of a rotating, maneuvering rotor system. The key element missing, which prevented significant advances, was our inability to precisely measure the exact rotor state as a function of time and flight condition. Two Rotor Research Aircraft (RSRA) were designed as pure research aircraft and dedicated rotor test vehicles whose function is to fill the gap between theory, wind tunnel testing, and flight verification. The two aircraft, the development of the piloting techniques required to safely fly the compound helicopter, the government flight testing accomplished to date, and proposed future research programs.

  4. Aircraft Vortex Spacing System (AVOSS) Concept and Development

    NASA Technical Reports Server (NTRS)

    Hinton, David A.

    1997-01-01

    The AVOSS goal is to: (1) Support TAP goal of improving instrument operations capacity 12-15% while maintaining safety; (2) Provide dynamical aircraft wake vortex spacing criteria to ATC systems at capacity limited facilities with required lead time and stability for use in establishing aircraft arrival scheduling; and (3) System development and concept demonstration. The AVOSS system concept is to separate aircraft from encounters with wake vortices of an operationally unacceptable strength. In doing so, define protected corridor from outer marker to runway and predict time for vortex to clear ("Transport Time"), define operationally unacceptable wake strength and predict time to decay ("Decay Time"), combine and provide to ATC automation ("Residence Time"), and monitor safety and provide predictor feedback with wake vortex detection subsystem.

  5. Design and flight test of the Propulsion Controlled Aircraft (PCA) flight control system on the NASA F-15 test aircraft

    NASA Technical Reports Server (NTRS)

    Wells, Edward A.; Urnes, James M., Sr.

    1994-01-01

    This report describes the design, development and flight testing of the Propulsion Controlled Aircraft (PCA) flight control system performed at McDonnell Douglas Aerospace (MDA), St. Louis, Missouri and at the NASA Dryden Flight Research Facility, Edwards Air Force Base, California. This research and development program was conducted by MDA and directed by NASA through the Dryden Flight Research Facility for the period beginning January 1991 and ending December 1993. A propulsion steering backup to the aircraft conventional flight control system has been developed and flight demonstrated on a NASA F-15 test aircraft. The Propulsion Controlled Aircraft (PCA) flight system utilizes collective and differential thrust changes to steer an aircraft that experiences partial or complete failure of the hydraulically actuated control surfaces. The PCA flight control research has shown that propulsion steering is a viable backup flight control mode and can assist the pilot in safe landing recovery of a fighter aircraft that has damage to or loss of the flight control surfaces. NASA, USAF and Navy evaluation test pilots stated that the F-15 PCA design provided the control necessary to land the aircraft. Moreover, the feasibility study showed that PCA technology can be directly applied to transport aircraft and provide a major improvement in the survivability of passengers and crew of controls damaged aircraft.

  6. Analysis and testing of stability augmentation systems. [for supersonic transport aircraft wing and B-52 aircraft control system

    NASA Technical Reports Server (NTRS)

    Sevart, F. D.; Patel, S. M.; Wattman, W. J.

    1972-01-01

    Testing and evaluation of stability augmentation systems for aircraft flight control were conducted. The flutter suppression system analysis of a scale supersonic transport wing model is described. Mechanization of the flutter suppression system is reported. The ride control synthesis for the B-52 aeroelastic model is discussed. Model analyses were conducted using equations of motion generated from generalized mass and stiffness data.

  7. Fuel-Conservation Guidance System for Powered-Lift Aircraft

    NASA Technical Reports Server (NTRS)

    Erzberger, Heinz; McLean, John D.

    1981-01-01

    A technique is described for the design of fuel-conservative guidance systems and is applied to a system that was flight tested on board NASA's sugmentor wing jet STOL research aircraft. An important operational feature of the system is its ability to rapidly synthesize fuel-efficient trajectories for a large set of initial aircraft positions, altitudes, and headings. This feature allows the aircraft to be flown efficiently under conditions of changing winds and air traffic control vectors. Rapid synthesis of fuel-efficient trajectories is accomplished in the airborne computer by fast-time trajectory integration using a simplified dynamic performance model of the aircraft. This technique also ensures optimum flap deployment and, for powered-lift STOL aircraft, optimum transition to low-speed flight. Also included in the design is accurate prediction of touchdown time for use in four-dimensional guidance applications. Flight test results have demonstrated that the automatically synthesized trajectories produce significant fuel savings relative to manually flown conventional approaches.

  8. Classification of Tropical Oceanic Precipitation using High-Altitude Aircraft Microwave and Electric Field Measurements

    NASA Technical Reports Server (NTRS)

    Hood, Robbie E.; Cecil, Daniel J.; LaFontaine, Frank J.; Blakeslee, Richard J.; Mach, Douglas m.; Heymsfield, Gerald M.; Marks, Frank D., Jr.; Zipser, Edward J.

    2004-01-01

    During the 1998 and 2001 hurricane seasons of the western Atlantic Ocean and Gulf of Mexico, the Advanced Microwave Precipitation Radiometer (AMPR), the ER-2 Doppler (EDOP) radar, and the Lightning Instrument Package (LIP) were flown aboard the NASA ER-2 high-altitude aircraft as part of the Third Convection and Moisture Experiment (CAMEX-3) and the Fourth Convection and Moisture Experiment (CAMEX-4). Several hurricanes, tropical storms, and other precipitation systems were sampled during these experiments. An oceanic rainfall screening technique has been developed using AMPR passive microwave observations of these systems collected at frequencies of 10.7, 19.35, 37.1, and 85.5 GHz. This technique combines the information content of the four AMPR frequencies regarding the gross vertical structure of hydrometeors into an intuitive and easily executable precipitation mapping format. The results have been verified using vertical profiles of EDOP reflectivity and lower-altitude horizontal reflectivity scans collected by the NOAA WP3D Orion radar. Matching the rainfall classification results with coincident electric field information collected by the LIP readily identifies convective rain regions within the precipitation fields. This technique shows promise as a real-time research and analysis tool for monitoring vertical updraft strength and convective intensity from airborne platforms such as remotely operated or uninhabited aerial vehicles. The technique is analyzed and discussed for a wide variety of precipitation types using the 26 August 1998 observations of Hurricane Bonnie near landfall.

  9. Classification of Tropical Oceanic Precipitation using High Altitude Aircraft: Microwave and Electric Field Measurements

    NASA Technical Reports Server (NTRS)

    Hood, Robbie E.; Cecil, Daniel; LaFontaine, Frank J.; Blakeslee, Richard; Mach, Douglas; Heymsfield, Gerald; Marks, Frank, Jr.; Zipser, Edward

    2004-01-01

    During the 1998 and 2001 hurricane seasons of the western Atlantic Ocean and Gulf of Mexico, the Advanced Microwave Precipitation Radiometer (AMPR), the ER-2 Doppler (EDOP) radar, and the Lightning Instrument Package (LIP) were flown aboard the National Aeronautics and Space Administration ER-2 high altitude aircraft as part of the Third Convection and Moisture Experiment (CAMEX-3) and the Fourth Convection and Moisture Experiment (CAMEX-4). Several hurricanes, tropical storms, and other precipitation systems were sampled during these experiments. An oceanic rainfall screening technique has been developed using AMPR passive microwave observations of these systems collected at frequencies of 10.7, 19.35,37.1, and 85.5 GHz. This technique combines the information content of the four AMPR frequencies regarding the gross vertical structure of hydrometeors into an intuitive and easily executable precipitation mapping format. The results have been verified using vertical profiles of EDOP reflectivity and lower altitude horizontal reflectivity scans collected by the National Oceanic and Atmospheric Administration WP-3D Orion radar. Matching the rainfall classification results with coincident electric field information collected by the LIP readily identifies convective rain regions within the precipitation fields. This technique shows promise as a real-time research and analysis tool for monitoring vertical updraft strength and convective intensity from airborne platforms such as remotely operated or uninhabited aerial vehicles. The technique is analyzed and discussed for a wide variety of precipitation types using the 26 August 1998 observations of Hurricane Bonnie near landfall.

  10. Aircraft Detection System Ensures Free-Space Laser Safety

    NASA Technical Reports Server (NTRS)

    Smithgall, Brian; Wilson, Keith E.

    2004-01-01

    As scientists continue to explore our solar system, there are increasing demands to return greater volumes of data from smaller deep-space probes. Accordingly, NASA is studying advanced strategies based on free-space laser transmissions, which offer secure, high-bandwidth communications using smaller subsystems of much lower power and mass than existing ones. These approaches, however, can pose a danger to pilots in the beam path because the lasers may illuminate aircraft and blind them. Researchers thus are investigating systems that will monitor the surrounding airspace for aircraft that could be affected. This paper presents current methods for safe free space laser propagation.

  11. Linear tracking systems with applications to aircraft control system design

    NASA Technical Reports Server (NTRS)

    Lee, W. H.; Athans, M.; Castanon, D.; Bacchioloni, F.

    1977-01-01

    A class of optimal linear time invariant tracking systems, both in continuous time and discrete time, of which the number of inputs (which are restricted to be step functions) is equal to the number of system outputs, is studied. Along with derivation of equations and design procedures, two discretization schemes are presented, constraining either the control or its time derivative, to be a constant over each sampling period. Descriptions are given for the linearized model of the F-8C aircraft longitudinal dynamics, and the C* handling qualities criterion, which then serve as an illustration of the applications of these linear tracking designs. A suboptimal reduced state design is also presented. Numerical results are given for both the continuous time and discrete time designs.

  12. Study of advanced fuel system concepts for commercial aircraft

    NASA Technical Reports Server (NTRS)

    Coffinberry, G. A.

    1985-01-01

    An analytical study was performed in order to assess relative performance and economic factors involved with alternative advanced fuel systems for future commercial aircraft operating with broadened property fuels. The DC-10-30 wide-body tri-jet aircraft and the CF6-8OX engine were used as a baseline design for the study. Three advanced systems were considered and were specifically aimed at addressing freezing point, thermal stability and lubricity fuel properties. Actual DC-10-30 routes and flight profiles were simulated by computer modeling and resulted in prediction of aircraft and engine fuel system temperatures during a nominal flight and during statistical one-day-per-year cold and hot flights. Emergency conditions were also evaluated. Fuel consumption and weight and power extraction results were obtained. An economic analysis was performed for new aircraft and systems. Advanced system means for fuel tank heating included fuel recirculation loops using engine lube heat and generator heat. Environmental control system bleed air heat was used for tank heating in a water recirculation loop. The results showed that fundamentally all of the three advanced systems are feasible but vary in their degree of compatibility with broadened-property fuel.

  13. Enhanced Airport Capacity Through Safe, Dynamic Reductions in Aircraft Separation: NASA's Aircraft VOrtex Spacing System (AVOSS)

    NASA Technical Reports Server (NTRS)

    OConnor, Cornelius J.; Rutishauser, David K.

    2001-01-01

    An aspect of airport terminal operations that holds potential for efficiency improvements is the separation criteria applied to aircraft for wake vortex avoidance. These criteria evolved to represent safe spacing under weather conditions conducive to the longest wake hazards, and are consequently overly conservative during a significant portion of operations. Under many ambient conditions, such as moderate crosswinds or turbulence, wake hazard durations are substantially reduced. To realize this reduction NASA has developed a proof-of-concept Aircraft Vortex Spacing System (AVOSS). Successfully operated in a real-time field demonstration during July 2000 at the Dallas Ft. Worth International Airport, AVOSS is a novel integration of weather sensors, wake sensors, and analytical wake prediction algorithms. Gains in airport throughput using AVOSS spacing as compared to the current criteria averaged 6%, with peak values approaching the theoretical maximum of 16%. The average throughput gain translates to 15-40% reductions in delay when applied to realistic capacity ratios at major airports.

  14. The Small Aircraft Transportation System Project: An Update

    NASA Technical Reports Server (NTRS)

    Kemmerly, Guy T.

    2006-01-01

    To all peoples in all parts of the world throughout history, the ability to move about easily is a fundamental element of freedom. The American people have charged NASA to increase their freedom and that of their children knowing that their quality of life will improve as our nation s transportation systems improve. In pursuit of this safe, reliable, and affordable personalized air transportation option, in 2000 NASA established the Small Aircraft Transportation System (SATS) Project. As the name suggests personalized air transportation would be built on smaller aircraft than those used by the airlines. Of course, smaller aircraft can operate from smaller airports and 96% of the American population is within thirty miles of a high-quality, underutilized community airport as are the vast majority of their customers, family members, and favorite vacation destinations.

  15. Systems and Methods for Collaboratively Controlling at Least One Aircraft

    NASA Technical Reports Server (NTRS)

    Estkowski, Regina I. (Inventor)

    2016-01-01

    An unmanned vehicle management system includes an unmanned aircraft system (UAS) control station controlling one or more unmanned vehicles (UV), a collaborative routing system, and a communication network connecting the UAS and the collaborative routing system. The collaborative routing system being configured to receive flight parameters from an operator of the UAS control station and, based on the received flight parameters, automatically present the UAS control station with flight plan options to enable the operator to operate the UV in a defined airspace.

  16. Aircraft noise synthesis system: Version 4 user instructions

    NASA Technical Reports Server (NTRS)

    Mccurdy, David A.; Sullivan, Brenda M.; Grandle, Robert E.

    1987-01-01

    A modified version of the Aircraft Noise Synthesis System with improved directivity and tonal content modeling has been developed. The synthesis system is used to provide test stimuli for studies of community annoyance to aircraft flyover noise. The computer-based system generates realistic, time-varying audio simulations of aircraft flyover noise at a specified observer location on the ground. The synthesis takes into account the time-varying aircraft position relative to the observer; specified reference spectra consisting of broadband, narrowband, and pure tone components; directivity patterns; Doppler shift; atmospheric effects; and ground effects. These parameters can be specified and controlled in such a way as to generate stimuli in which certain noise characteristics such as duration or tonal content are independently varied while the remaining characteristics such as broadband content are held constant. The modified version of the system provides improved modeling of noise directivity patterns and an increased number of pure tone components. User instructions for the modified version of the synthesis system are provided.

  17. SOFC-Gas Turbine Hybrid System for Aircraft Applications: Modeling and Performance Analysis

    NASA Astrophysics Data System (ADS)

    Srivastava, Nischal

    2005-11-01

    There is a growing interest in fuel cells for aircraft applications. Fuel cells when combined with conventional turbine power plants offer high fuel efficiencies. The feature of fuel cells (SOFC, MCFC) used in aircraft applications, which makes them suitable for hybrid systems, is their high operating temperature. Their dynamic nature, both electrical and thermodynamic, demands a dynamic study of the complete hybrid cycle. In this paper we present a model for a SOFC/Gas Turbine hybrid system and its implementation in Matlab-Simulink. The main focus of the paper is on the dynamic analysis of the combined SOFC/GT cycle. Various configurations of the hybrid system are proposed and simulated. A comparative study of the simulated configurations, based on the first and second laws of thermodynamics, is presented. An exergy analysis for the chosen configuration is used to perform a parametric study of the overall hybrid system performance.

  18. Multiplexing electro-optic architectures for advanced aircraft integrated flight control systems

    NASA Technical Reports Server (NTRS)

    Seal, D. W.

    1989-01-01

    This report describes the results of a 10 month program sponsored by NASA. The objective of this program was to evaluate various optical sensor modulation technologies and to design an optimal Electro-Optic Architecture (EOA) for servicing remote clusters of sensors and actuators in advanced aircraft flight control systems. The EOA's supply optical power to remote sensors and actuators, process the modulated optical signals returned from the sensors, and produce conditioned electrical signals acceptable for use by a digital flight control computer or Vehicle Management System (VMS) computer. This study was part of a multi-year initiative under the Fiber Optic Control System Integration (FOCSI) program to design, develop, and test a totally integrated fiber optic flight/propulsion control system for application to advanced aircraft. Unlike earlier FOCSI studies, this program concentrated on the design of the EOA interface rather than the optical transducer technology itself.

  19. Application of dynamical systems theory to nonlinear aircraft dynamics

    NASA Technical Reports Server (NTRS)

    Culick, Fred E. C.; Jahnke, Craig C.

    1988-01-01

    Dynamical systems theory has been used to study nonlinear aircraft dynamics. A six degree of freedom model that neglects gravity has been analyzed. The aerodynamic model, supplied by NASA, is for a generic swept wing fighter and includes nonlinearities as functions of the angle of attack. A continuation method was used to calculate the steady states of the aircraft, and bifurcations of these steady states, as functions of the control deflections. Bifurcations were used to predict jump phenomena and the onset of periodic motion for roll coupling instabilities and high angle of attack maneuvers. The predictions were verified with numerical simulations.

  20. Integrated numerical methods for hypersonic aircraft cooling systems analysis

    NASA Technical Reports Server (NTRS)

    Petley, Dennis H.; Jones, Stuart C.; Dziedzic, William M.

    1992-01-01

    Numerical methods have been developed for the analysis of hypersonic aircraft cooling systems. A general purpose finite difference thermal analysis code is used to determine areas which must be cooled. Complex cooling networks of series and parallel flow can be analyzed using a finite difference computer program. Both internal fluid flow and heat transfer are analyzed, because increased heat flow causes a decrease in the flow of the coolant. The steady state solution is a successive point iterative method. The transient analysis uses implicit forward-backward differencing. Several examples of the use of the program in studies of hypersonic aircraft and rockets are provided.

  1. Canada's first fixed-site aircraft noise monitoring system

    SciTech Connect

    Standen, N.M.

    1982-01-01

    The nature of aircraft noise management in Canada as it is presently evolving is discussed. The population of aircraft operating in Canada is similar to most western nations with regard to aircraft type. Canada's airport system includes major airports owned and operated by the federal Department of Transport (Transport Canada), airports owned and operated by provinces, municipalities or local commissions, and privately owned and operated airports, largely catering to general aviation. In addition, there are airports which are owned by Transport Canada, but operated by another agency. The consequence of this arrangement is that the major jet transport traffic is handled by airports which are owned and operated by either Transport Canada or another government agency.

  2. System level airworthiness tool: A comprehensive approach to small unmanned aircraft system airworthiness

    NASA Astrophysics Data System (ADS)

    Burke, David A.

    One of the pillars of aviation safety is assuring sound engineering practices through airworthiness certification. As Unmanned Aircraft Systems (UAS) grow in popularity, the need for airworthiness standards and verification methods tailored for UAS becomes critical. While airworthiness practices for large UAS may be similar to manned aircraft, it is clear that small UAS require a paradigm shift from the airworthiness practices of manned aircraft. Although small in comparison to manned aircraft these aircraft are not merely remote controlled toys. Small UAS may be complex aircraft flying in the National Airspace System (NAS) over populated areas for extended durations and beyond line of sight of the operators. A comprehensive systems engineering framework for certifying small UAS at the system level is needed. This work presents a point based tool that evaluates small UAS by rewarding good engineering practices in design, analysis, and testing. The airworthiness requirements scale with vehicle size and operational area, while allowing flexibility for new technologies and unique configurations.

  3. A multiple objective optimization approach to aircraft control systems design

    NASA Technical Reports Server (NTRS)

    Tabak, D.; Schy, A. A.; Johnson, K. G.; Giesy, D. P.

    1979-01-01

    The design of an aircraft lateral control system, subject to several performance criteria and constraints, is considered. While in the previous studies of the same model a single criterion optimization, with other performance requirements expressed as constraints, has been pursued, the current approach involves a multiple criteria optimization. In particular, a Pareto optimal solution is sought.

  4. A practical scheme for adaptive aircraft flight control systems

    NASA Technical Reports Server (NTRS)

    Athans, M.; Willner, D.

    1974-01-01

    A flight control system design is presented, that can be implemented by analog hardware, to be used to control an aircraft with uncertain parameters. The design is based upon the use of modern control theory. The ideas are illustrated by considering control of STOL longitudinal dynamics.

  5. Sense and avoid technology for unmanned aircraft systems

    NASA Astrophysics Data System (ADS)

    McCalmont, John; Utt, James; Deschenes, Michael; Taylor, Michael; Sanderson, Richard; Montgomery, Joel; Johnson, Randal S.; McDermott, David

    2007-04-01

    The Sensors Directorate of the Air Force Research Laboratory (AFRL), in conjunction with the Global Hawk Systems Group, the J-UCAS System Program Office and contractor Defense Research Associates, Inc. (DRA) is conducting an Advanced Technology Demonstration (ATD) of a sense-and-avoid capability with the potential to satisfy the Federal Aviation Administration's (FAA) requirement for Unmanned Aircraft Systems (UAS) to provide "an equivalent level of safety, comparable to see-and-avoid requirements for manned aircraft". This FAA requirement must be satisfied for UAS operations within the national airspace. The Sense-and-Avoid, Phase I (Man-in-the-Loop) and Phase II (Autonomous Maneuver) ATD demonstrated an on-board, wide field of regard, multi-sensor visible imaging system operating in real time and capable of passively detecting approaching aircraft, declaring potential collision threats in a timely manner and alerting the human pilot located in the remote ground control station or autonomously maneuvered the aircraft. Intruder declaration data was collected during the SAA I & II Advanced Technology Demonstration flights conducted during December 2006. A total of 27 collision scenario flights were conducted and analyzed. The average detection range was 6.3 NM and the mean declaration range was 4.3 NM. The number of false alarms per engagement has been reduced to approximately 3 per engagement.

  6. 78 FR 68360 - Unmanned Aircraft System Test Site Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-14

    ... comments published in the Federal Register on February 22, 2013 (78 FR 12259), Docket No. FAA-2013-0061... (78 FR 18932), Docket No. FAA-2013-0061- 0050. In addition, this document publishes the FAA's Final... Federal Aviation Administration 14 CFR Part 91 Unmanned Aircraft System Test Site Program AGENCY:...

  7. Propulsion Systems for Aircraft. Aerospace Education II. Instructional Unit II.

    ERIC Educational Resources Information Center

    Elmer, James D.

    This curriculum guide accompanies another publication in the Aerospace Education II series entitled "Propulsion Systems for Aircraft." The guide includes specific guidelines for teachers on each chapter in the textbook. Suggestions are included for objectives (traditional and behavioral), suggested outline, orientation, suggested key points,…

  8. Detection of nitrogen deficiency in potatoes using unmanned aircraft systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Small Unmanned Aircraft Systems (sUAS) are recognized as potentially important remote-sensing platforms for precision agriculture. We set up a nitrogen rate experiment in 2013 with ‘Ranger Russet’ potatoes by applying four rates of nitrogen fertilizer (112, 224, 337, and 449 kg N/ha) in a randomized...

  9. Remote sensing with unmanned aircraft systems for precision agriculture applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Federal Aviation Administration is revising regulations for using unmanned aircraft systems (UAS) in the national airspace. An important potential application of UAS may be as a remote-sensing platform for precision agriculture, but simply down-scaling remote sensing methodologies developed usi...

  10. Obstacle detection and warning system for aircraft navigation at airports

    NASA Astrophysics Data System (ADS)

    Gallo, Laurent

    2000-06-01

    This paper speaks about work conducted in 1998 and 1999 by AEROSPATIALE MATRA in development of an obstacle detection system, which has been tested on a demonstrator aircraft in Toulouse. The purpose of this mock- up was to verify the feasibility of a passive technology, and to consider the limits of its use.

  11. Loss-of-Control-Inhibitor Systems for Aircraft

    NASA Technical Reports Server (NTRS)

    AHarrah, Ralph C.

    2007-01-01

    Systems to provide improved tactile feedback to aircraft pilots are being developed to help the pilots maintain harmony between their control actions and the positions of aircraft control surfaces, thereby helping to prevent loss of control. A system of this type, denoted a loss-of-control-inhibitor system (LOCIS) can be implemented as a relatively simple addition to almost any pre-existing flight-control system. The LOCIS concept offers at least a partial solution to the problem of (1) keeping a pilot aware of the state of the control system and the aircraft and (2) maintaining sufficient control under conditions that, as described below, have been known to lead to loss of control. Current commercial aircraft exhibit uneven responses of primary flight-control surfaces to aggressive pilot control commands, leading to deterioration of pilots ability to control their aircraft. In severe cases, this phenomenon can result in loss of control and consequent loss of aircraft. For an older aircraft equipped with a purely mechanical control system, the loss of harmony between a pilot s command action and the control- surface response can be attributed to compliance in the control system (caused, for example, by stretching of control cables, flexing of push rods, or servo-valve distortion). In a newer aircraft equipped with a fly-by-wire control system, the major contributions to loss of harmony between the pilot and the control surfaces are delays attributable to computer cycle time, control shaping, filtering, aliasing, servo-valve distortion, and actuator rate limiting. In addition, a fly-by-wire control system provides no tactile feedback that would enable the pilot to sense such features of the control state as surface flutter, surface jam, position limiting, actuator rate limiting, and control limiting imposed by the aircraft operational envelope. Hence, for example, when a pilot is involved in aggressive closed-loop maneuvering, as when encountering a wake

  12. Aircraft interrogation and display system: A ground support equipment for digital flight systems

    NASA Technical Reports Server (NTRS)

    Glover, R. D.

    1982-01-01

    A microprocessor-based general purpose ground support equipment for electronic systems was developed. The hardware and software are designed to permit diverse applications in support of aircraft flight systems and simulation facilities. The implementation of the hardware, the structure of the software, describes the application of the system to an ongoing research aircraft project are described.

  13. Information fusion based optimal control for large civil aircraft system.

    PubMed

    Zhen, Ziyang; Jiang, Ju; Wang, Xinhua; Gao, Chen

    2015-03-01

    Wind disturbance has a great influence on landing security of Large Civil Aircraft. Through simulation research and engineering experience, it can be found that PID control is not good enough to solve the problem of restraining the wind disturbance. This paper focuses on anti-wind attitude control for Large Civil Aircraft in landing phase. In order to improve the riding comfort and the flight security, an information fusion based optimal control strategy is presented to restrain the wind in landing phase for maintaining attitudes and airspeed. Data of Boeing707 is used to establish a nonlinear mode with total variables of Large Civil Aircraft, and then two linear models are obtained which are divided into longitudinal and lateral equations. Based on engineering experience, the longitudinal channel adopts PID control and C inner control to keep longitudinal attitude constant, and applies autothrottle system for keeping airspeed constant, while an information fusion based optimal regulator in the lateral control channel is designed to achieve lateral attitude holding. According to information fusion estimation, by fusing hard constraint information of system dynamic equations and the soft constraint information of performance index function, optimal estimation of the control sequence is derived. Based on this, an information fusion state regulator is deduced for discrete time linear system with disturbance. The simulation results of nonlinear model of aircraft indicate that the information fusion optimal control is better than traditional PID control, LQR control and LQR control with integral action, in anti-wind disturbance performance in the landing phase. PMID:25440950

  14. TOPEX electrical power system

    NASA Technical Reports Server (NTRS)

    Chetty, P. R. K.; Roufberg, Lew; Costogue, Ernest

    1991-01-01

    The TOPEX mission requirements which impact the power requirements and analyses are presented. A description of the electrical power system (EPS), including energy management and battery charging methods that were conceived and developed to meet the identified satellite requirements, is included. Analysis of the TOPEX EPS confirms that all of its electrical performance and reliability requirements have been met. The TOPEX EPS employs the flight-proven modular power system (MPS) which is part of the Multimission Modular Spacecraft and provides high reliability, abbreviated development effort and schedule, and low cost. An energy balance equation, unique to TOPEX, has been derived to confirm that the batteries will be completely recharged following each eclipse, under worst-case conditions. TOPEX uses three NASA Standard 50AH Ni-Cd batteries, each with 22 cells in series. The MPS contains battery charge control and protection based on measurements of battery currents, voltages, temperatures, and computed depth-of-discharge. In case of impending battery depletion, the MPS automatically implements load shedding.

  15. Study of advanced fuel system concepts for commercial aircraft and engines

    NASA Technical Reports Server (NTRS)

    Versaw, E. F.; Brewer, G. D.; Byers, W. D.; Fogg, H. W.; Hanks, D. E.; Chirivella, J.

    1983-01-01

    The impact on a commercial transport aircraft of using fuels which have relaxed property limits relative to current commercial jet fuel was assessed. The methodology of the study is outlined, fuel properties are discussed, and the effect of the relaxation of fuel properties analyzed. Advanced fuel system component designs that permit the satisfactory use of fuel with the candidate relaxed properties in the subject aircraft are described. The two fuel properties considered in detail are freezing point and thermal stability. Three candidate fuel system concepts were selected and evaluated in terms of performance, cost, weight, safety, and maintainability. A fuel system that incorporates insulation and electrical heating elements on fuel tank lower surfaces was found to be most cost effective for the long term.

  16. 78 FR 7816 - NASA Advisory Council; Aeronautics Committee; Unmanned Aircraft Systems Subcommittee Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-04

    ... From the Federal Register Online via the Government Publishing Office NATIONAL AERONAUTICS AND SPACE ADMINISTRATION NASA Advisory Council; Aeronautics Committee; Unmanned Aircraft Systems... Aeronautics and Space Administration announces a meeting of the Unmanned Aircraft Systems (UAS)...

  17. 78 FR 25100 - NASA Advisory Council; Aeronautics Committee; Unmanned Aircraft Systems Subcommittee; Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-29

    ... From the Federal Register Online via the Government Publishing Office NATIONAL AERONAUTICS AND SPACE ADMINISTRATION NASA Advisory Council; Aeronautics Committee; Unmanned Aircraft Systems... Aeronautics and Space Administration announces a meeting of the Unmanned Aircraft Systems (UAS)...

  18. 77 FR 59020 - NASA Advisory Council; Aeronautics Committee; Unmanned Aircraft Systems Subcommittee; Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-25

    ... From the Federal Register Online via the Government Publishing Office NATIONAL AERONAUTICS AND SPACE ADMINISTRATION NASA Advisory Council; Aeronautics Committee; Unmanned Aircraft Systems... Aeronautics and Space Administration announces a meeting of the Unmanned Aircraft Systems (UAS)...

  19. Flight testing the Rotor Systems Research Aircraft (RSRA)

    NASA Technical Reports Server (NTRS)

    Merrill, R. K.; Hall, G. W.

    1982-01-01

    The Rotor Systems Research Aircraft (RSRA) is a dedicated rotor test vehicle whose function is to fill the gap between theory, wind tunnel tests and flight verification data. Its flight test envelope has been designed to encompass the expected envelopes of future rotor systems under all flight conditions. The test configurations of the RSRA include pure helicopter and compound (winged helicopter) modes. In addition, should it become necessary to jettison an unstable rotor system in flight, the RSRA may be flown as a fixed wing aircraft. The heart of the RSRA's electronic flight control system is the TDY-43 computer, which can be programmed in numerous ways to change stability and control or force feel system gains. Computer programming changes allow the RSRA to be used as a five-degree-of-freedom inflight simulator for studying the handling qualities of research rotors.

  20. An integrated computer system for preliminary design of advanced aircraft.

    NASA Technical Reports Server (NTRS)

    Fulton, R. E.; Sobieszczanski, J.; Landrum, E. J.

    1972-01-01

    A progress report is given on the first phase of a research project to develop a system of Integrated Programs for Aerospace-Vehicle Design (IPAD) which is intended to automate to the largest extent possible the preliminary and detailed design of advanced aircraft. The approach used is to build a pilot system and simultaneously to carry out two major contractual studies to define a practical IPAD system preparatory to programing. The paper summarizes the specifications and goals of the IPAD system, the progress to date, and any conclusion reached regarding its feasibility and scope. Sample calculations obtained with the pilot system are given for aircraft preliminary designs optimized with respect to discipline parameters, such as weight or L/D, and these results are compared with designs optimized with respect to overall performance parameters, such as range or payload.

  1. Electric vehicle drive systems

    NASA Astrophysics Data System (ADS)

    Appleyard, M.

    1992-01-01

    New legislation in the State of California requires that 2% of vehicles sold there from 1998 will be 'zero-emitting'. This provides a unique market opportunity for developers of electric vehicles but substantial improvements in the technology are probably required if it is to be successfully exploited. There are around a dozen types of battery that are potentially relevant to road vehicles but, at the present, lead/acid and sodium—sulphur come closest to combining acceptable performance, life and cost. To develop an efficient, lightweight electric motor system requires up-to-date techniques of magnetics design, and the latest power-electronic and microprocessor control methods. Brushless machines, coupled with solid-state inverters, offer the most economical solution for mass production, even though their development costs are higher than for direct-current commutator machines. Fitted to a small car, even the highest energy-density batteries will only provide around 200 km average range before recharging. Therefore, some form of supplementary on-board power generation will probably be needed to secure widespread acceptance by the driving public. Engine-driven generators of quite low power can achieve useful increases in urban range but will fail to qualify as 'zero-emitting'. On the other hand, if the same function could be economically performed by a small fuel-cell using hydrogen derived from a methanol reformer, then most of the flexibility provided by conventional vehicles would be retained. The market prospects for electric cars would then be greatly enhanced and their dependence on very advanced battery technology would be reduced.

  2. Secondary Wing System for Use on an Aircraft

    NASA Technical Reports Server (NTRS)

    Smith, Brian E. (Inventor)

    1999-01-01

    A secondary wing system for use on an aircraft augments the lift, stability, and control of the aircraft at subsonic speeds. The secondary wing system includes a mechanism that allows the canard to be retracted within the contour of the aircraft fuselage from an operational position to a stowed position. The top surface of the canard is exposed to air flow in the stowed position, and is contoured to integrate aerodynamically and smoothly within the contour of the fuselage when the canard is retracted for high speed flight. The bottom portion of the canard is substantially flat for rotation into a storage recess within the fuselage. The single canard rotates about a vertical axis at its spanwise midpoint. The canard can be positioned between a range of sweep angles during flight and a stowed position in which its span is substantially parallel to the aircraft fuselage. The canard can be deployed and retracted during flight. The deployment mechanism includes a circular mounting ring and drive mechanism that connects the canard with the fuselage and permits it to rotate and to change incidence. The deployment mechanism further includes retractable fairings which serve to streamline the wing when it is retracted into the top of the fuselage.

  3. Theoretical analysis of the electrical aspects of the basic electro-impulse problem in aircraft de-icing applications

    NASA Technical Reports Server (NTRS)

    Henderson, Robert A.; Schrag, Robert L.

    1987-01-01

    A method of modelling a system consisting of a cylindrical coil with its axis perpendicular to a metal plate of finite thickness, and a simple electrical circuit for producing a transient current in the coil, is discussed in the context of using such a system for de-icing aircraft surfaces. A transmission line model of the coil and metal plate is developed as the heart of the system model. It is shown that this transmission model is central to calculation of the coil impedance, the coil current, the magnetic fields established on the surfaces of the metal plate, and the resultant total force between the coil and the plate. FORTRAN algorithms were developed for numerical calculation of each of these quantities, and the algorithms were applied to an experimental prototype system in which these quantities had been measured. Good agreement is seen to exist between the predicted and measured results.

  4. Rotor systems research aircraft risk-reduction shake test

    NASA Technical Reports Server (NTRS)

    Wellman, J. Brent

    1990-01-01

    A shake test and an extensive analysis of results were performed to evaluate the possibility of and the method for dynamically calibrating the Rotor Systems Research Aircraft (RSRA). The RSRA airframe was subjected to known vibratory loads in several degrees of freedom and the responses of many aircraft transducers were recorded. Analysis of the transducer responses using the technique of dynamic force determination showed that the RSRA, when used as a dynamic measurement system, could predict, a posteriori, an excitation force in a single axis to an accuracy of about 5 percent and sometimes better. As the analysis was broadened to include multiple degrees of freedom for the excitation force, the predictive ability of the measurement system degraded to about 20 percent, with the error occasionally reaching 100 percent. The poor performance of the measurement system is explained by the nonlinear response of the RSRA to vibratory forces and the inadequacy of the particular method used in accounting for this nonlinearity.

  5. 76 FR 24957 - Nineteenth Meeting: RTCA Special Committee 203: Unmanned Aircraft Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-03

    ... Federal Aviation Administration Nineteenth Meeting: RTCA Special Committee 203: Unmanned Aircraft Systems...: Unmanned Aircraft Systems. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 203: Unmanned Aircraft Systems. DATES: The meeting will be held May 17-19,...

  6. Energy efficient engine: Propulsion system-aircraft integration evaluation

    NASA Technical Reports Server (NTRS)

    Owens, R. E.

    1979-01-01

    Flight performance and operating economics of future commercial transports utilizing the energy efficient engine were assessed as well as the probability of meeting NASA's goals for TSFC, DOC, noise, and emissions. Results of the initial propulsion systems aircraft integration evaluation presented include estimates of engine performance, predictions of fuel burns, operating costs of the flight propulsion system installed in seven selected advanced study commercial transports, estimates of noise and emissions, considerations of thrust growth, and the achievement-probability analysis.

  7. Aircraft optimization by a system approach: Achievements and trends

    NASA Technical Reports Server (NTRS)

    Sobieszczanski-Sobieski, Jaroslaw

    1992-01-01

    Recently emerging methodology for optimal design of aircraft treated as a system of interacting physical phenomena and parts is examined. The methodology is found to coalesce into methods for hierarchic, non-hierarchic, and hybrid systems all dependent on sensitivity analysis. A separate category of methods has also evolved independent of sensitivity analysis, hence suitable for discrete problems. References and numerical applications are cited. Massively parallel computer processing is seen as enabling technology for practical implementation of the methodology.

  8. Aircraft structural health monitoring using on-board BOCDA system

    NASA Astrophysics Data System (ADS)

    Yari, Takashi; Nagai, Kanehiro; Ishioka, Masahito; Hotate, Kazuo; Koshioka, Yasuhiro

    2008-03-01

    We developed the on-board BOCDA system for airplane and verified the flight environmental stability and durability through environmental test. The on-board BOCDA system adopted the polarization diversity technique and temporal gating technique to improve robustness of the BOCDA system. We successfully measured distribution of fiber Brillouin gain spectrum over 500m measurement range with 50mm spatial resolution, 60Hz sampling rate and +/-13μ strain accuracy. Furthermore, we considered flight test to verify the validity of the BOCDA system. From these results, it was confirmed that BOCDA system has potential to be applied to an aircraft structure health monitoring system.

  9. Environmental fog/rain visual display system for aircraft simulators

    NASA Technical Reports Server (NTRS)

    Chase, W. D. (Inventor)

    1982-01-01

    An environmental fog/rain visual display system for aircraft simulators is described. The electronic elements of the system include a real time digital computer, a caligraphic color display which simulates landing lights of selective intensity, and a color television camera for producing a moving color display of the airport runway as depicted on a model terrain board. The mechanical simulation elements of the system include an environmental chamber which can produce natural fog, nonhomogeneous fog, rain and fog combined, or rain only. A pilot looking through the aircraft wind screen will look through the fog and/or rain generated in the environmental chamber onto a viewing screen with the simulated color image of the airport runway thereon, and observe a very real simulation of actual conditions of a runway as it would appear through actual fog and/or rain.

  10. An assessment of the risk arising from electrical effects associated with carbon fibers released from commercial aircraft fires

    NASA Technical Reports Server (NTRS)

    Kalelkar, A. S.; Fiksel, J.; Rosenfield, D.; Richardson, D. L.; Hagopian, J.

    1980-01-01

    The risks associated with electrical effects arising from carbon fibers released from commercial aviation aircraft fires were estimated for 1993. The expected annual losses were estimated to be about $470 (1977 dollars) in 1993. The chances of total losses from electrical effects exceeding $100,000 (1977 dollars) in 1993 were established to be about one in ten thousand.

  11. Design of an infrared camera based aircraft detection system for laser guide star installations

    SciTech Connect

    Friedman, H.; Macintosh, B.

    1996-03-05

    There have been incidents in which the irradiance resulting from laser guide stars have temporarily blinded pilots or passengers of aircraft. An aircraft detection system based on passive near infrared cameras (instead of active radar) is described in this report.

  12. An advanced control system for a next generation transport aircraft

    NASA Technical Reports Server (NTRS)

    Rising, J. J.; Davis, W. J; Grantham, W. D.

    1983-01-01

    The use of modern control theory to develop a high-authority stability and control system for the next generation transport aircraft is described with examples taken from work performed on an advanced pitch active control system (PACS). The PACS was configured to have short-period and phugoid modes frequency and damping characteristics within the shaded S-plane areas, column force gradients with set bounds and with constant slope, and a blended normal-acceleration/pitch rate time history response to a step command. Details of the control law, feedback loop, and modal control syntheses are explored, as are compensation for the feedback gain, the deletion of the velocity signal, and the feed-forward compensation. Scheduling of the primary and secondary gains are discussed, together with control law mechanization, flying qualities analyses, and application on the L-1011 aircraft.

  13. 75 FR 2925 - Sixteenth Plenary Meeting: RTCA Special Committee 203: Unmanned Aircraft Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-19

    ... Federal Aviation Administration Sixteenth Plenary Meeting: RTCA Special Committee 203: Unmanned Aircraft...: Unmanned Aircraft Systems. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 203: Unmanned Aircraft Systems. DATES: The meeting will be held February...

  14. 77 FR 3029 - Twentieth Meeting: RTCA Special Committee 203, Unmanned Aircraft Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-20

    ... Federal Aviation Administration Twentieth Meeting: RTCA Special Committee 203, Unmanned Aircraft Systems... RTCA Special Committee 203, Unmanned Aircraft Systems. SUMMARY: The FAA is issuing this notice to advise the public of the twentieth meeting of RTCA Special Committee 203, Unmanned Aircraft...

  15. 75 FR 60495 - Eighteenth Plenary Meeting: RTCA Special Committee 203: Unmanned Aircraft Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-30

    ... Federal Aviation Administration Eighteenth Plenary Meeting: RTCA Special Committee 203: Unmanned Aircraft...: Unmanned Aircraft Systems. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 203: Unmanned Aircraft Systems. DATES: The meeting will be held October...

  16. 75 FR 26321 - Seventeenth Plenary Meeting: RTCA Special Committee 203: Unmanned Aircraft Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-11

    ... Federal Aviation Administration Seventeenth Plenary Meeting: RTCA Special Committee 203: Unmanned Aircraft...: Unmanned Aircraft Systems. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 203: Unmanned Aircraft Systems. DATES: The meeting will be held June 8-10,...

  17. Performance of an Electro-Hydrostatic Actuator on the F-18 Systems Research Aircraft

    NASA Technical Reports Server (NTRS)

    Navarro, Robert

    1997-01-01

    An electro-hydrostatic actuator was evaluated at NASA Dryden Flight Research Center, Edwards, California. The primary goal of testing this actuator system was the flight demonstration of power-by-wire technology on a primary flight control surface. The electro-hydrostatic actuator uses an electric motor to drive a hydraulic pump and relies on local hydraulics for force transmission. This actuator replaced the F-18 standard left aileron actuator on the F-18 Systems Research Aircraft and was evaluated throughout the Systems Research Aircraft flight envelope. As of July 24, 1997 the electro-hydrostatic actuator had accumulated 23.5 hours of flight time. This paper presents the electro-hydrostatic actuator system configuration and component description, ground and flight test plans, ground and flight test results, and lessons learned. This actuator performs as well as the standard actuator and has more load capability than required by aileron actuator specifications of McDonnell- Douglas Aircraft, St. Louis, Missouri. The electro-hydrostatic actuator system passed all of its ground tests with the exception of one power-off test during unloaded dynamic cycling.

  18. Flight Test Experience with an Electromechanical Actuator on the F-18 Systems Research Aircraft

    NASA Technical Reports Server (NTRS)

    Jensen, Stephen C.; Jenney, Gavin D.; Raymond, Bruce; Dawson, David; Flick, Brad (Technical Monitor)

    2000-01-01

    Development of reliable power-by-wire actuation systems for both aeronautical and space applications has been sought recently to eliminate hydraulic systems from aircraft and spacecraft and thus improve safety, efficiency, reliability, and maintainability. The Electrically Powered Actuation Design (EPAD) program was a joint effort between the Air Force, Navy, and NASA to develop and fly a series of actuators validating power-by-wire actuation technology on a primary flight control surface of a tactical aircraft. To achieve this goal, each of the EPAD actuators was installed in place of the standard hydraulic actuator on the left aileron of the NASA F/A-18B Systems Research Aircraft (SRA) and flown throughout the SRA flight envelope. Numerous parameters were recorded, and overall actuator performance was compared with the performance of the standard hydraulic actuator on the opposite wing. This paper discusses the integration and testing of the EPAD electromechanical actuator (EMA) on the SRA. The architecture of the EMA system is discussed, as well as its integration with the F/A-18 Flight Control System. The flight test program is described, and actuator performance is shown to be very close to that of the standard hydraulic actuator it replaced. Lessons learned during this program are presented and discussed, as well as suggestions for future research.

  19. Flight Test Experience With an Electromechanical Actuator on the F-18 Systems Research Aircraft

    NASA Technical Reports Server (NTRS)

    Jensen, Stephen C.; Jenney, Gavin D.; Raymond, Bruce; Dawson, David

    2000-01-01

    Development of reliable power-by-wire actuation systems for both aeronautical and space applications has been sought recently to eliminate hydraulic systems from aircraft and spacecraft and thus improve safety, efficiency, reliability, and maintainability. The Electrically Powered Actuation Design (EPAD) program was a joint effort between the Air Force, Navy, and NASA to develop and fly a series of actuators validating power-by-wire actuation technology on a primary flight control surface of a tactical aircraft. To achieve this goal, each of the EPAD actuators was installed in place of the standard hydraulic actuator on the left aileron of the NASA F/A-18B Systems Research Aircraft (SRA) and flown throughout the SRA flight envelope. Numerous parameters were recorded, and overall actuator performance was compared with the performance of the standard hydraulic actuator on the opposite wing. This paper discusses the integration and testing of the EPAD electromechanical actuator (EMA) on the SRA. The architecture of the EMA system is discussed, as well as its integration with the F/A-18 Flight Control System. The flight test program is described, and actuator performance is shown to be very close to that of the standard hydraulic actuator it replaced. Lessons learned during this program are presented and discussed, as well as suggestions for future research.

  20. Aircraft concepts for advanced short haul systems

    NASA Technical Reports Server (NTRS)

    Galloway, T. L.

    1975-01-01

    The results of recent NASA-sponsored high-density and medium-density short-haul (less than 500 miles) air transportation systems studies are summarized. Trends in vehicle characteristics, in particular of RTOL and STOL concepts, are noted, and their economic suitability and impact on the community are examined.

  1. Study of aircraft in intraurban transportation systems, volume 3

    NASA Technical Reports Server (NTRS)

    Stout, E. G.; Kesling, P. H.; Matteson, D. E.; Sherwood, D. E.; Tuck, W. R., Jr.; Vaughn, L. A.

    1971-01-01

    An investigation of three aircraft concepts, deflected slipstream STOL, helicopter VTOL, and fixed wing STOL, is presented. An attempt was made to determine the best concept for the intraurban transportation system. Desirability of the concept was based on ease of maintenance, development timing, reliability, operating costs, and the noise produced. Indications are that the deflected slipstream STOL is best suited for intraurban transportation. Tables and graphs are included.

  2. Utilization of separate surface control systems on general aviation aircraft

    NASA Technical Reports Server (NTRS)

    Roskam, J.

    1977-01-01

    The application of separate surface control systems to general aviation aircraft is discussed. Block diagrams of a conventional control system with autopilot tie-in and of a separate surface control system are presented, and the advantages and disadvantages of the two systems are compared. Theoretical descriptions of pilot-in-the-loop operation and operation in the autopilot mode are presented. The application of separate surface stability augmentation in yaw dampers, wing levelers, and static longitudinal stability augmentation is examined. The state-of-the-art of separate control surface technology is summarized.

  3. Hierarchical Discrete Event Supervisory Control of Aircraft Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Yasar, Murat; Tolani, Devendra; Ray, Asok; Shah, Neerav; Litt, Jonathan S.

    2004-01-01

    This paper presents a hierarchical application of Discrete Event Supervisory (DES) control theory for intelligent decision and control of a twin-engine aircraft propulsion system. A dual layer hierarchical DES controller is designed to supervise and coordinate the operation of two engines of the propulsion system. The two engines are individually controlled to achieve enhanced performance and reliability, necessary for fulfilling the mission objectives. Each engine is operated under a continuously varying control system that maintains the specified performance and a local discrete-event supervisor for condition monitoring and life extending control. A global upper level DES controller is designed for load balancing and overall health management of the propulsion system.

  4. System IDentification Programs for AirCraft (SIDPAC)

    NASA Technical Reports Server (NTRS)

    Morelli, Eugene A.

    2002-01-01

    A collection of computer programs for aircraft system identification is described and demonstrated. The programs, collectively called System IDentification Programs for AirCraft, or SIDPAC, were developed in MATLAB as m-file functions. SIDPAC has been used successfully at NASA Langley Research Center with data from many different flight test programs and wind tunnel experiments. SIDPAC includes routines for experiment design, data conditioning, data compatibility analysis, model structure determination, equation-error and output-error parameter estimation in both the time and frequency domains, real-time and recursive parameter estimation, low order equivalent system identification, estimated parameter error calculation, linear and nonlinear simulation, plotting, and 3-D visualization. An overview of SIDPAC capabilities is provided, along with a demonstration of the use of SIDPAC with real flight test data from the NASA Glenn Twin Otter aircraft. The SIDPAC software is available without charge to U.S. citizens by request to the author, contingent on the requestor completing a NASA software usage agreement.

  5. A Small Aircraft Transportation System (SATS) Demand Model

    NASA Technical Reports Server (NTRS)

    Long, Dou; Lee, David; Johnson, Jesse; Kostiuk, Peter; Yackovetsky, Robert (Technical Monitor)

    2001-01-01

    The Small Aircraft Transportation System (SATS) demand modeling is a tool that will be useful for decision-makers to analyze SATS demands in both airport and airspace. We constructed a series of models following the general top-down, modular principles in systems engineering. There are three principal models, SATS Airport Demand Model (SATS-ADM), SATS Flight Demand Model (SATS-FDM), and LMINET-SATS. SATS-ADM models SATS operations, by aircraft type, from the forecasts in fleet, configuration and performance, utilization, and traffic mixture. Given the SATS airport operations such as the ones generated by SATS-ADM, SATS-FDM constructs the SATS origin and destination (O&D) traffic flow based on the solution of the gravity model, from which it then generates SATS flights using the Monte Carlo simulation based on the departure time-of-day profile. LMINET-SATS, an extension of LMINET, models SATS demands at airspace and airport by all aircraft operations in US The models use parameters to provide the user with flexibility and ease of use to generate SATS demand for different scenarios. Several case studies are included to illustrate the use of the models, which are useful to identify the need for a new air traffic management system to cope with SATS.

  6. Aircraft Low Altitude Wind Shear Detection and Warning System.

    NASA Astrophysics Data System (ADS)

    Sinclair, Peter C.; Kuhn, Peter M.

    1991-01-01

    There is now considerable evidence to substantiate the causal relationship between low altitude wind shear (LAWS) and the recent increase in low-altitude aircraft accidents. The National Research Council has found that for the period 1964 to 1982, LAWS was involved in nearly all the weather-related air carrier fatalities. However, at present, there is no acceptable method, technique, or hardware system that provides the necessary safety margins, for spatial and timely detection of LAWS from an aircraft during the critical phases of landing and takeoff. The Federal Aviation Administration (FAA) has addressed this matter and supports the development of an airborne system for detecting hazardous LAWS with at least a one minute warning of the potential hazard to the pilot. One of the purposes of this paper is to show from some of our preliminary flight measurement research that a forward looking infrared radiometer (FLIR) system can be used to successfully detect the cool downdraft of downbursts [microbursts/macrobursts (MB)] and thunderstorm gust front outflows that are responsible for most of the LAWS events. The FLIR system provides a much greater safety margin for the pilot than that provided by reactive designs such as inertial-air speed systems that require the actual penetration of the MB before a pilot warning can be initiated. Our preliminary results indicate that an advanced airborne FLIR system could provide the pilot with remote indication of MB threat, location, movement, and predicted MB hazards along the flight path ahead of the aircraft.In a proof-of-concept experiment, we have flight tested a prototype FLIR system (nonscanning, fixed range) near and within Colorado MBs with excellent detectability. The results show that a minimum warning time of one-four minutes (5×10 km), depending on aircraft speed, is available to the pilot prior to a MB encounter. Analysis of the flight data with respect to a modified `hazard index' indicates the severe hazard

  7. On the safety of aircraft systems: A case study

    SciTech Connect

    Martinez-Guridi, G.; Hall, R.E.; Fullwood, R.R.

    1997-05-14

    An airplane is a highly engineered system incorporating control- and feedback-loops which often, and realistically, are non-linear because the equations describing such feedback contain products of state variables, trigonometric or square-root functions, or other types of non-linear terms. The feedback provided by the pilot (crew) of the airplane also is typically non-linear because it has the same mathematical characteristics. An airplane is designed with systems to prevent and mitigate undesired events. If an undesired triggering event occurs, an accident may process in different ways depending on the effectiveness of such systems. In addition, the progression of some accidents requires that the operating crew take corrective action(s), which may modify the configuration of some systems. The safety assessment of an aircraft system typically is carried out using ARP (Aerospace Recommended Practice) 4761 (SAE, 1995) methods, such as Fault Tree Analysis (FTA) and Failure Mode and Effects Analysis (FMEA). Such methods may be called static because they model an aircraft system on its nominal configuration during a mission time, but they do not incorporate the action(s) taken by the operating crew, nor the dynamic behavior (non-linearities) of the system (airplane) as a function of time. Probabilistic Safety Assessment (PSA), also known as Probabilistic Risk Assessment (PRA), has been applied to highly engineered systems, such as aircraft and nuclear power plants. PSA encompasses a wide variety of methods, including event tree analysis (ETA), FTA, and common-cause analysis, among others. PSA should not be confused with ARP 4761`s proposed PSSA (Preliminary System Safety Assessment); as its name implies, PSSA is a preliminary assessment at the system level consisting of FTA and FMEA.

  8. High-Altitude Aircraft-Based Electric-Field Measurements above Thunderstorms

    NASA Technical Reports Server (NTRS)

    Bateman, M. G.; Blakeslee, R. J.; Bailey, J. C.; Stewart, M. F.; Blair, A. K.

    1999-01-01

    We have developed a new set of eight electric field mills that were flown on a NASA ER-2 high-altitude aircraft. During the Third Convection And Moisture EXperiment (CAMEX- 3; Fall, 1998), measurements of electric field, storm dynamics, and ice microphysics were made over several hurricanes. Concurrently, the TExas-FLorida UNderflights (TEFLUN) program was being conducted to make the same measurements over Gulf Coast thunderstorms. Sample measurements will be shown. Our new mills have an internal 16-bit A/D, with a resolution of 0.25 V/m per bit at high gain, with a noise level less than the least significant bit. A second, lower gain channel gives us the ability to measure fields as high as 150 kV/m.

  9. High-Altitude Aircraft-Based Electric-Field Measurements Above Thunderstorms

    NASA Technical Reports Server (NTRS)

    Bateman, M. G.; Blakeslee, R. J.; Bailey, J. C.; Stewart, M. F.; Blair, A. K.

    1999-01-01

    We have developed a new set of eight electric field mills that were flown on a NASA ER-2 high-altitude aircraft. During the Third Convection And Moisture EXperiment (CAMEX-3; Fall, 1998), measurements of electric field, storm dynamics, and ice microphysics were made over several hurricanes. Concurrently, the TExas-FLorida UNderflights (TEFLUN) program was being conducted to make the same measurements over Gulf Coast thunderstorms. Sample measurements are shown: typical flight altitude is 20km. Our new mills have an internal 16-bit A/D, with a resolution of 0.25V/m per bit at high gain, with a noise level less than the least significant bit. A second, lower gain channel gives us the ability to measure fields as high as 150 kV/m.

  10. Aircraft measurements of the atmospheric electrical global circuit during the period 1971-1984

    NASA Technical Reports Server (NTRS)

    Markson, R.

    1985-01-01

    This report will update an investigation of the global circuit conducted over the last 14 years through aircraft measurements of the variation of ionospheric potential and associated parameters. The data base included electric field, conductivity, and air-earth current density profiles from the tropics (25 deg N) to the Arctic (79 deg N). Almost all of the data have been obtained over the ocean to reduce noise associated with local generators, aerosols, and convection. Recently, two aircraft have been utilized to obtain, for the first time, quasi-periodic sets of simultaneous ionospheric potential (VI) soundings at remote locations and extending over time spans sufficiently long so that the universal time diurnal variation (Carnegie curve) could be observed. In additon, these measurements provided the first detection of the modulation of electric fields in the troposphere caused by the double vortex ionospheric convection pattern. Besides summarizing these measurements and comparing them to similar data obtained by other groups, this report discusses meteorological sources of error and criteria for determining if the global circuit is being measured rather than variations caused by local meteorological processes.

  11. Retrieving Storm Electric Fields From Aircraft Field Mill Data. Part 2; Applications

    NASA Technical Reports Server (NTRS)

    Koshak, W. J.; Mach, D. M.; Christian, H. J.; Stewart, M. F.; Bateman, M. G.

    2005-01-01

    The Lagrange multiplier theory and "pitch down method" developed in Part I of this study are applied to complete the calibration of a Citation aircraft that is instrumented with six field mill sensors. When side constraints related to average fields are used, the method performs well in computer simulations. For mill measurement errors of 1 V/m and a 5 V/m error in the mean fair weather field function, the 3-D storm electric field is retrieved to within an error of about 12%. A side constraint that involves estimating the detailed structure of the fair weather field was also tested using computer simulations. For mill measurement errors of 1 V/m, the method retrieves the 3-D storm field to within an error of about 8% if the fair weather field estimate is typically within 1 V/m of the true fair weather field. Using this side constraint and data from fair weather field maneuvers taken on 29 June 2001, the Citation aircraft was calibrated. The resulting calibration matrix was then used to retrieve storm electric fields during a Citation flight on 2 June 2001. The storm field results are encouraging and agree favorably with the results obtained from earlier calibration analyses that were based on iterative techniques.

  12. Global Electric Circuit Implications of Combined Aircraft Storm Electric Current Measurements and Satellite-Based Diurnal Lightning Statistics

    NASA Technical Reports Server (NTRS)

    Mach, Douglas M.; Blakeslee, Richard J.; Bateman, Monte G.

    2011-01-01

    Using rotating vane electric field mills and Gerdien capacitors, we measured the electric field profile and conductivity during 850 overflights of thunderstorms and electrified shower clouds (ESCs) spanning regions including the Southeastern United States, the Western Atlantic Ocean, the Gulf of Mexico, Central America and adjacent oceans, Central Brazil, and the South Pacific. The overflights include storms over land and ocean, and with positive and negative fields above the storms. Over three-quarters (78%) of the land storms had detectable lightning, while less than half (43%) of the oceanic storms had lightning. Integrating our electric field and conductivity data, we determined total conduction currents and flash rates for each overpass. With knowledge of the storm location (land or ocean) and type (with or without lightning), we determine the mean currents by location and type. The mean current for ocean thunderstorms is 1.7 A while the mean current for land thunderstorms is 1.0 A. The mean current for ocean ESCs 0.41 A and the mean current for land ESCs is 0.13 A. We did not find any significant regional or latitudinal based patterns in our total conduction currents. By combining the aircraft derived storm currents and flash rates with diurnal flash rate statistics derived from the Lightning Imaging Sensor (LIS) and Optical Transient Detector (OTD) low Earth orbiting satellites, we reproduce the diurnal variation in the global electric circuit (i.e., the Carnegie curve) to within 4% for all but two short periods of time. The agreement with the Carnegie curve was obtained without any tuning or adjustment of the satellite or aircraft data. Given our data and assumptions, mean contributions to the global electric circuit are 1.1 kA (land) and 0.7 kA (ocean) from thunderstorms, and 0.22 kA (ocean) and 0.04 (land) from ESCs, resulting in a mean total conduction current estimate for the global electric circuit of 2.0 kA. Mean storm counts are 1100 for land

  13. Flight Test of ASAC Aircraft Interior Noise Control System

    NASA Technical Reports Server (NTRS)

    Palumbo, Dan; Cabell, Ran; Cline, John; Sullivan, Brenda

    1999-01-01

    A flight test is described in which an active structural/acoustic control system reduces turboprop induced interior noise on a Raytheon Aircraft Company 1900D airliner. Control inputs to 21 inertial force actuators were computed adaptively using a transform domain version of the multichannel filtered-X LMS algorithm to minimize the mean square response of 32 microphones. A combinatorial search algorithm was employed to optimize placement of the force actuators on the aircraft frame. Both single frequency and multi-frequency results are presented. Reductions of up to 15 dB were obtained at the blade passage frequency (BPF) during single frequency control tests. Simultaneous reductions of the BPF and next 2 harmonics of 10 dB, 2.5 dB and 3.0 dB, were obtained in a multi-frequency test.

  14. Fault-tolerant software for aircraft control systems

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Concepts for software to implement real time aircraft control systems on a centralized digital computer were discussed. A fault tolerant software structure employing functionally redundant routines with concurrent error detection was proposed for critical control functions involving safety of flight and landing. A degraded recovery block concept was devised to allow collocation of critical and noncritical software modules within the same control structure. The additional computer resources required to implement the proposed software structure for a representative set of aircraft control functions were discussed. It was estimated that approximately 30 percent more memory space is required to implement the total set of control functions. A reliability model for the fault tolerant software was described and parametric estimates of failure rate were made.

  15. Real-Time Minimization of Tracking Error for Aircraft Systems

    NASA Technical Reports Server (NTRS)

    Garud, Sumedha; Kaneshige, John T.; Krishnakumar, Kalmanje S.; Kulkarni, Nilesh V.; Burken, John

    2013-01-01

    This technology presents a novel, stable, discrete-time adaptive law for flight control in a Direct adaptive control (DAC) framework. Where errors are not present, the original control design has been tuned for optimal performance. Adaptive control works towards achieving nominal performance whenever the design has modeling uncertainties/errors or when the vehicle suffers substantial flight configuration change. The baseline controller uses dynamic inversion with proportional-integral augmentation. On-line adaptation of this control law is achieved by providing a parameterized augmentation signal to a dynamic inversion block. The parameters of this augmentation signal are updated to achieve the nominal desired error dynamics. If the system senses that at least one aircraft component is experiencing an excursion and the return of this component value toward its reference value is not proceeding according to the expected controller characteristics, then the neural network (NN) modeling of aircraft operation may be changed.

  16. Structural Configuration Systems Analysis for Advanced Aircraft Fuselage Concepts

    NASA Technical Reports Server (NTRS)

    Mukhopadhyay, Vivek; Welstead, Jason R.; Quinlan, Jesse R.; Guynn, Mark D.

    2016-01-01

    Structural configuration analysis of an advanced aircraft fuselage concept is investigated. This concept is characterized by a double-bubble section fuselage with rear mounted engines. Based on lessons learned from structural systems analysis of unconventional aircraft, high-fidelity finite-element models (FEM) are developed for evaluating structural performance of three double-bubble section configurations. Structural sizing and stress analysis are applied for design improvement and weight reduction. Among the three double-bubble configurations, the double-D cross-section fuselage design was found to have a relatively lower structural weight. The structural FEM weights of these three double-bubble fuselage section concepts are also compared with several cylindrical fuselage models. Since these fuselage concepts are different in size, shape and material, the fuselage structural FEM weights are normalized by the corresponding passenger floor area for a relative comparison. This structural systems analysis indicates that an advanced composite double-D section fuselage may have a relative structural weight ratio advantage over a conventional aluminum fuselage. Ten commercial and conceptual aircraft fuselage structural weight estimates, which are empirically derived from the corresponding maximum takeoff gross weight, are also presented and compared with the FEM- based estimates for possible correlation. A conceptual full vehicle FEM model with a double-D fuselage is also developed for preliminary structural analysis and weight estimation.

  17. Aircraft and satellite thermographic systems for wildfire mapping and assessment

    NASA Technical Reports Server (NTRS)

    Brass, J. A.; Arvesen, J. C.; Ambrosia, V. G.; Riggan, P. J.; Myers, J. S.

    1987-01-01

    Two complementary sensors, the DAEDALUS DEI-1260 Multispectral Scanner aboard the NASA U-2 aircraft and the Advanced Very High Resolution Radiometer aboard National Oceanographic and Atmospheric Administration orbiting satellites were tested for their applicability in monitoring and predicting parameters such as fire location, temperature and rate of spread, soil heating and cooling rates, and plume characteristics and dimensions. In addition, the satellite system was tested for its ability to extend the relationships found between fire characteristics and biospheric consequences to regional and global scales. An overall system design is presented, and special requirements are documented for the application of this system for fire research and management.

  18. Fuel characteristics pertinent to the design of aircraft fuel systems

    NASA Technical Reports Server (NTRS)

    Barnett, Henry C; Hibbard, R R

    1953-01-01

    Because of the importance of fuel properties in design of aircraft fuel systems the present report has been prepared to provide information on the characteristics of current jet fuels. In addition to information on fuel properties, discussions are presented on fuel specifications, the variations among fuels supplied under a given specification, fuel composition, and the pertinence of fuel composition and physical properties to fuel system design. In some instances the influence of variables such as pressure and temperature on physical properties is indicated. References are cited to provide fuel system designers with sources of information containing more detail than is practicable in the present report.

  19. Dynamics of aircraft antiskid braking systems. [conducted at the Langley aircraft landing loads and traction facility

    NASA Technical Reports Server (NTRS)

    Tanner, J. A.; Stubbs, S. M.; Dreher, R. C.; Smith, E. G.

    1982-01-01

    A computer study was performed to assess the accuracy of three brake pressure-torque mathematical models. The investigation utilized one main gear wheel, brake, and tire assembly of a McDonnell Douglas DC-9 series 10 airplane. The investigation indicates that the performance of aircraft antiskid braking systems is strongly influenced by tire characteristics, dynamic response of the antiskid control valve, and pressure-torque response of the brake. The computer study employed an average torque error criterion to assess the accuracy of the models. The results indicate that a variable nonlinear spring with hysteresis memory function models the pressure-torque response of the brake more accurately than currently used models.

  20. Portable Integrated Wireless Device Threat Assessment to Aircraft Radio Systems

    NASA Technical Reports Server (NTRS)

    Salud, Maria Theresa P.; Williams, Reuben A. (Technical Monitor)

    2004-01-01

    An assessment was conducted on multiple wireless local area network (WLAN) devices using the three wireless standards for spurious radiated emissions to determine their threat to aircraft radio navigation systems. The measurement process, data and analysis are provided for devices tested using IEEE 802.11a, IEEE 802.11b, and Bluetooth as well as data from portable laptops/tablet PCs and PDAs (grouping known as PEDs). A comparison was made between wireless LAN devices and portable electronic devices. Spurious radiated emissions were investigated in the radio frequency bands for the following aircraft systems: Instrument Landing System Localizer and Glideslope, Very High Frequency (VHF) Communication, VHF Omnidirectional Range, Traffic Collision Avoidance System, Air Traffic Control Radar Beacon System, Microwave Landing System and Global Positioning System. Since several of the contiguous navigation systems were grouped under one encompassing measurement frequency band, there were five measurement frequency bands where spurious radiated emissions data were collected for the PEDs and WLAN devices. The report also provides a comparison between emissions data and regulatory emission limit.

  1. Advances towards the qualification of an aircraft fuel tank inert environment fiber optic oxygen sensor system

    NASA Astrophysics Data System (ADS)

    Mendoza, Edgar A.; Esterkin, Yan; Kempen, Cornelia; Sun, Songjian; Susko, Kenneth; Goglia, John

    2011-06-01

    An all optical pressure and temperature compensated fiber optic oxygen sensor (FOxSenseTM) system is under qualification for use in the in-situ closed-loop-control of the inert atmosphere environment inside fuel tanks of military and commercial aircraft. The all-optical oxygen environment control sensor is a passive, intrinsically safe, fiber-optic sensor device with no electrical connections leading to the sensors installed within the fuel tanks of an aircraft. To control the fuel tank environment, an array of multiple sensors is deployed throughout the fuel tanks of an aircraft, and a remote multi-channel optoelectronic system is used to monitor the status of all the sensors in real time to provide feedback oxygen environment information to the on-board inert gas generating system (OBIGS). Qualification testing of the all optical sensor have demonstrated the ability to monitor the oxygen environment inside a simulated fuel tank environment in the oxygen range from 0% to 21% oxygen concentrations, temperatures from (-) 40°C to (+) 60°C, and altitudes from sea level to 40,000 feet. Fiber optic oxygen sensors with built-in temperature compensation as well as the conduit fiber optic cables have passed DO-160E including acoustic noise and burn test.

  2. Electric propulsion system technology

    NASA Technical Reports Server (NTRS)

    Brophy, John R.; Garner, Charles E.; Goodfellow, Keith D.

    1991-01-01

    model enables one to calculate the flow direction and local density of the charge exchange plasma, and indicates the degree to which this plasma can flow upstream of the thruster exhaust plane. A continuing effort to investigate the most desirable throttling technique for noble gas ion thrusters concentrated this year on experimentally determining the fixed flow rate throttling range of a 30-cm dia. thruster with a two-grid accelerator system. These experiments demonstrated a throttling capability which covers a 2.8 to 1 variation in input power. This throttling range is 55 percent greater than expected, and is due to better accelerator system performance at low net-to-total voltage ratios than indicated in the literature. To facilitate the development of large, higher power ion thrusters several brief studies were performed. These include the development of a technique which simulates ion thruster operation without beam extraction, the development of an optical technique to measure ion thruster grid distortion due to thermal expansion, tests of a capacitance measurement technique to quantify the accelerator system grid separation, and the development of a segmented thruster geometry which enables near term development of ion thrusters at power levels greater than 100 kW. Finally, a paper detailing the benefits of electric propulsion for the Space Exploration Initiative was written.

  3. Combined Aircraft and Satellite-Derived Storm Electric Current and Lightning Rates Measurements and Implications for the Global Electric Circuit

    NASA Technical Reports Server (NTRS)

    Mach, Douglas M.; Blakeslee, Richard J.; Bateman, Monte G.

    2010-01-01

    Using rotating vane electric field mills and Gerdien capacitors, we measured the electric field profile and conductivity during 850 overflights of electrified shower clouds and thunderstorms spanning regions including the Southeastern United States, the Western Atlantic Ocean, the Gulf of Mexico, Central America and adjacent oceans, Central Brazil, and the South Pacific. The overflights include storms over land and ocean, with and without lightning, and with positive and negative fields above the storms. The measurements were made with the NASA ER-2 and the Altus-II high altitude aircrafts. Peak electric fields, with lightning transients removed, ranged from -1.0 kV/m to 16 kV/m, with a mean value of 0.9 kV/m. The median peak field was 0.29 kV/m. Integrating our electric field and conductivity data, we determined total conduction currents and flash rates for each overpass. With knowledge of the storm location (land or ocean) and type (with or without lightning), we determine the mean currents by location and type. The mean current for ocean storms with lightning is 1.6 A while the mean current for land storms with lightning is 1.0 A. The mean current for oceanic storms without lightning (i.e., electrified shower clouds) is 0.39 A and the mean current for land storms without lightning is 0.13 A. Thus, on average, land storms with or without lightning have about half the mean current as their corresponding oceanic storm counterparts. Over three-quarters (78%) of the land storms had detectable lightning, while less than half (43%) of the oceanic storms had lightning. We did not find any significant regional or latitudinal based patterns in our total conduction currents. By combining the aircraft derived storm currents and flash rates with diurnal lightning statistics derived from the Lightning Imaging Sensor (LIS) and Optical Transient Detector (OTD) low Earth orbiting satellites, we reproduce the diurnal variation in the global electric circuit (i.e., the Carnegie

  4. Analysis of Small Aircraft as a Transportation System

    NASA Technical Reports Server (NTRS)

    Dollyhigh, Samuel M.; Yackovetsky, Robert E. (Technical Monitor)

    2002-01-01

    An analysis was conducted to examine the market viability of small aircraft as a transportation mode in competition with automobile and scheduled commercial air travel by estimating the pool of users that would potentially switch to on-demand air travel due to cost/time savings. The basis for the analysis model was the Integrated Air Transportation System Evaluation Tool (IATSET) which was developed under contract to NASA by the Logistics Management Institute. IATSET is a macroeconomic model that predicts at a National level the mode choice between automobile, scheduled air, and on-demand air travel based on the value of a travelers time and monetary cost of the trip. A number of modifications are detailed to the original IATSET to better model the changing small aircraft environment. The potential trip market was modeled for the Eclipse 500 operated as a corporate jet and as an air taxi for the business travel market. The Cirrus 20R and a $80K single engine piston aircraft (based on automobile manufacturing technology) are evaluated in the pleasure and personal business travel market.

  5. Propulsion System for Very High Altitude Subsonic Unmanned Aircraft

    NASA Technical Reports Server (NTRS)

    Bents, David J.; Mockler, Ted; Maldonado, Jaime; Harp, James L., Jr.; King, Joseph F.; Schmitz, Paul C.

    1998-01-01

    This paper explains why a spark ignited gasoline engine, intake pressurized with three cascaded stages of turbocharging, was selected to power NASA's contemplated next generation of high altitude atmospheric science aircraft. Beginning with the most urgent science needs (the atmospheric sampling mission) and tracing through the mission requirements which dictate the unique flight regime in which this aircraft has to operate (subsonic flight at greater then 80 kft) we briefly explore the physical problems and constraints, the available technology options and the cost drivers associated with developing a viable propulsion system for this highly specialized aircraft. The paper presents the two available options (the turbojet and the turbocharged spark ignited engine) which are discussed and compared in the context of the flight regime. We then show how the unique nature of the sampling mission, coupled with the economic considerations pursuant to aero engine development, point to the spark ignited engine as the only cost effective solution available. Surprisingly, this solution compares favorably with the turbojet in the flight regime of interest. Finally, some remarks are made about NASA's present state of development, and future plans to flight demonstrate the three stage turbocharged powerplant.

  6. Optical wireless networked-systems: applications to aircrafts

    NASA Astrophysics Data System (ADS)

    Kavehrad, Mohsen; Fadlullah, Jarir

    2011-01-01

    This paper focuses on leveraging the progress in semiconductor technologies to facilitate production of efficient light-based in-flight entertainment (IFE), distributed sensing, navigation and control systems. We demonstrate the ease of configuring "engineered pipes" using cheap lenses, etc. to achieve simple linear transmission capacity growth. Investigation of energy-efficient, miniaturized transceivers will create a wireless medium, for both inter and intra aircrafts, providing enhanced security, and improved quality-of-service for communications links in greater harmony with onboard systems. The applications will seamlessly inter-connect multiple intelligent devices in a network that is deployable for aircrafts navigation systems, onboard sensors and entertainment data delivery systems, and high-definition audio-visual broadcasting systems. Recent experimental results on a high-capacity infrared (808 nm) system are presented. The light source can be applied in a hybrid package along with a visible lighting LED for both lighting and communications. Also, we present a pragmatic combination of light communications through "Spotlighting" and existing onboard power-lines. It is demonstrated in details that a high-capacity IFE visible light system communicating over existing power-lines (VLC/PLC) may lead to savings in many areas through reduction of size, weight and energy consumption. This paper addresses the challenges of integrating optimized optical devices in the variety of environments described above, and presents mitigation and tailoring approaches for a multi-purpose optical network.

  7. Method and apparatus for monitoring aircraft components

    DOEpatents

    Dickens, Larry M.; Haynes, Howard D.; Ayers, Curtis W.

    1996-01-01

    Operability of aircraft mechanical components is monitored by analyzing the voltage output of an electrical generator of the aircraft. Alternative generators, for a turbine-driven rotor aircraft, include the gas producer turbine tachometer generator, the power turbine tachometer generator, and the aircraft systems power producing starter/generator. Changes in the peak amplitudes of the fundamental frequency and its harmonics are correlated to changes in condition of the mechanical components.

  8. Method and apparatus for monitoring aircraft components

    DOEpatents

    Dickens, L.M.; Haynes, H.D.; Ayers, C.W.

    1996-01-16

    Operability of aircraft mechanical components is monitored by analyzing the voltage output of an electrical generator of the aircraft. Alternative generators, for a turbine-driven rotor aircraft, include the gas producer turbine tachometer generator, the power turbine tachometer generator, and the aircraft systems power producing starter/generator. Changes in the peak amplitudes of the fundamental frequency and its harmonics are correlated to changes in condition of the mechanical components. 14 figs.

  9. The StarBooster System: A Cargo Aircraft for Space

    NASA Technical Reports Server (NTRS)

    Davis, Hubert P.; Dula, Arthur M.; McLaughlin, Don; Frassanito, John; Andrews, Jason (Editor)

    1999-01-01

    Starcraft Boosters has developed a different approach for lowering the cost of access to space. We propose developing a new aircraft that will house an existing expendable rocket stage. This vehicle, termed StarBooster, will be the first stage of a family of launch vehicles. By combining these elements, we believe we can reduce the cost and risk of fielding a new partially reusable launch system. This report summarizes the work performed on the StarBooster concept since the company's inception in 1996. Detailed analyses are on-going and future reports will focus on the maturation of the vehicle and system design.

  10. Aircraft wire system laboratory development : phase I progress report.

    SciTech Connect

    Dinallo, Michael Anthony; Lopez, Christopher D.

    2003-08-01

    An aircraft wire systems laboratory has been developed to support technical maturation of diagnostic technologies being used in the aviation community for detection of faulty attributes of wiring systems. The design and development rationale of the laboratory is based in part on documented findings published by the aviation community. The main resource at the laboratory is a test bed enclosure that is populated with aged and newly assembled wire harnesses that have known defects. This report provides the test bed design and harness selection rationale, harness assembly and defect fabrication procedures, and descriptions of the laboratory for usage by the aviation community.

  11. Accurate aircraft wind measurements using the global positioning system (GPS)

    SciTech Connect

    Dobosy, R.J.; Crawford, T.L., McMillen, R.T., Dumas, E.J.

    1996-11-01

    High accuracy measurements of the spatial distribution of wind speed are required in the study of turbulent exchange between the atmosphere and the earth. The use of a differential global positioning system (GPS) to determine the sensor velocity vector component of wind speed is discussed in this paper. The results of noise and rocking testing are summarized, and fluxes obtained from the GPS-based methods are compared to those measured from systems on towers and airplanes. The GPS-based methods provided usable measurements that compared well with tower and aircraft data at a significantly lower cost. 21 refs., 1 fig., 2 tabs.

  12. The Proposed Use of Unmanned Aerial System Surrogate Research Aircraft for National Airspace System Integration Research

    NASA Technical Reports Server (NTRS)

    Howell, Charles T., III

    2011-01-01

    Research is needed to determine what procedures, aircraft sensors and other systems will be required to allow Unmanned Aerial Systems (UAS) to safely operate with manned aircraft in the National Airspace System (NAS). This paper explores the use of Unmanned Aerial System (UAS) Surrogate research aircraft to serve as platforms for UAS systems research, development, and flight testing. These aircraft would be manned with safety pilots and researchers that would allow for flight operations almost anywhere in the NAS without the need for a Federal Aviation Administration (FAA) Certificate of Authorization (COA). With pilot override capability, these UAS Surrogate aircraft would be controlled from ground stations like true UAS s. It would be possible to file and fly these UAS Surrogate aircraft in the NAS with normal traffic and they would be better platforms for real world UAS research and development over existing vehicles flying in restricted ranges or other sterilized airspace. These UAS surrogate aircraft could be outfitted with research systems as required such as computers, state sensors, video recording, data acquisition, data link, telemetry, instrumentation, and Automatic Dependent Surveillance-Broadcast (ADS-B). These surrogate aircraft could also be linked to onboard or ground based simulation facilities to further extend UAS research capabilities. Potential areas for UAS Surrogate research include the development, flight test and evaluation of sensors to aide in the process of air traffic "see-and-avoid". These and other sensors could be evaluated in real-time and compared with onboard human evaluation pilots. This paper examines the feasibility of using UAS Surrogate research aircraft as test platforms for a variety of UAS related research.

  13. The development of a parachute system for aerial delivery from high speed cargo aircraft

    SciTech Connect

    Behr, V.L.

    1992-12-31

    Supply of military personnel on the ground with cargo has long been accomplished with parachute delivery systems from aircraft. Structural limits of aircraft have typically limited these operations to no more than 150 KCAS. A desire for increased survivability of cargo delivery aircraft has led to the development and fielding of aircraft capable of delivering cargo at substantially higher speeds. This paper describes efforts undertaken to design develop and test a cargo delivery system for use at speeds compatible with those high speed cargo aircraft.

  14. The development of a parachute system for aerial delivery from high speed cargo aircraft

    SciTech Connect

    Behr, V.L.

    1992-01-01

    Supply of military personnel on the ground with cargo has long been accomplished with parachute delivery systems from aircraft. Structural limits of aircraft have typically limited these operations to no more than 150 KCAS. A desire for increased survivability of cargo delivery aircraft has led to the development and fielding of aircraft capable of delivering cargo at substantially higher speeds. This paper describes efforts undertaken to design develop and test a cargo delivery system for use at speeds compatible with those high speed cargo aircraft.

  15. Control law system for X-Wing aircraft

    NASA Technical Reports Server (NTRS)

    Lawrence, Thomas H. (Inventor); Gold, Phillip J. (Inventor)

    1990-01-01

    Control law system for the collective axis, as well as pitch and roll axes, of an X-Wing aircraft and for the pneumatic valving controlling circulation control blowing for the rotor. As to the collective axis, the system gives the pilot single-lever direct lift control and insures that maximum cyclic blowing control power is available in transition. Angle-of-attach de-coupling is provided in rotary wing flight, and mechanical collective is used to augment pneumatic roll control when appropriate. Automatic gain variations with airspeed and rotor speed are provided, so a unitary set of control laws works in all three X-Wing flight modes. As to pitch and roll axes, the system produces essentially the same aircraft response regardless of flight mode or condition. Undesirable cross-couplings are compensated for in a manner unnoticeable to the pilot without requiring pilot action, as flight mode or condition is changed. A hub moment feedback scheme is implemented, utilizing a P+I controller, significantly improving bandwidth. Limits protect aircraft structure from inadvertent damage. As to pneumatic valving, the system automatically provides the pressure required at each valve azimuth location, as dictated by collective, cyclic and higher harmonic blowing commands. Variations in the required control phase angle are automatically introduced, and variations in plenum pressure are compensated for. The required switching for leading, trailing and dual edge blowing is automated, using a simple table look-up procedure. Non-linearities due to valve characteristics of circulation control lift are linearized by map look-ups.

  16. Electrical Stunning Systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This presentation is an overview of the mechanics of electrical stunning of broilers and the physiology associated with stunning, bleeding, and the rapid progression to death. Stunning and bleeding compose a relative short time period in the 6-week life of a commercial broiler, about 2.5 to 3 minut...

  17. Wind farm electrical system

    DOEpatents

    Erdman, William L.; Lettenmaier, Terry M.

    2006-07-04

    An approach to wind farm design using variable speed wind turbines with low pulse number electrical output. The output of multiple wind turbines are aggregated to create a high pulse number electrical output at a point of common coupling with a utility grid network. Power quality at each individual wind turbine falls short of utility standards, but the aggregated output at the point of common coupling is within acceptable tolerances for utility power quality. The approach for aggregating low pulse number electrical output from multiple wind turbines relies upon a pad mounted transformer at each wind turbine that performs phase multiplication on the output of each wind turbine. Phase multiplication converts a modified square wave from the wind turbine into a 6 pulse output. Phase shifting of the 6 pulse output from each wind turbine allows the aggregated output of multiple wind turbines to be a 24 pulse approximation of a sine wave. Additional filtering and VAR control is embedded within the wind farm to take advantage of the wind farm's electrical impedence characteristics to further enhance power quality at the point of common coupling.

  18. Diesel Mechanics: Electrical Systems.

    ERIC Educational Resources Information Center

    Foutes, William; And Others

    This publication is the second in a series of three texts for a diesel mechanics curriculum. Its purpose is to teach the concepts related to electricity and circuitry in a diesel trade. The text contains nine units. Each instructional unit includes some or all of these basic components: unit and specific (performance) objectives, suggested…

  19. Pilot-aircraft system reponse to wind shear

    NASA Technical Reports Server (NTRS)

    Turkel, B. S.; Frost, W.

    1980-01-01

    The nonlinear aircraft motion and automatic control model is expanded to incorporate the human pilot into simulations of aircraft response to wind to wind shear. The human pilot is described by a constant gains lag filter. Two runs are carried out using pilot transfer functions. Fixed-stick, autopilot, and manned computer simulations are made with an aircraft having characteristics of a small commuter type aircraft flown through longitudinal winds measured by a Doppler radar beamed along the glide slope. Simulations are also made flying an aircraft through sinusoidal head wind and tail wind shears at the phugoid frequency to evaluate the response of manned aircraft in thunderstorm wind environments.

  20. Multi-level systems modeling and optimization for novel aircraft

    NASA Astrophysics Data System (ADS)

    Subramanian, Shreyas Vathul

    This research combines the disciplines of system-of-systems (SoS) modeling, platform-based design, optimization and evolving design spaces to achieve a novel capability for designing solutions to key aeronautical mission challenges. A central innovation in this approach is the confluence of multi-level modeling (from sub-systems to the aircraft system to aeronautical system-of-systems) in a way that coordinates the appropriate problem formulations at each level and enables parametric search in design libraries for solutions that satisfy level-specific objectives. The work here addresses the topic of SoS optimization and discusses problem formulation, solution strategy, the need for new algorithms that address special features of this problem type, and also demonstrates these concepts using two example application problems - a surveillance UAV swarm problem, and the design of noise optimal aircraft and approach procedures. This topic is critical since most new capabilities in aeronautics will be provided not just by a single air vehicle, but by aeronautical Systems of Systems (SoS). At the same time, many new aircraft concepts are pressing the boundaries of cyber-physical complexity through the myriad of dynamic and adaptive sub-systems that are rising up the TRL (Technology Readiness Level) scale. This compositional approach is envisioned to be active at three levels: validated sub-systems are integrated to form conceptual aircraft, which are further connected with others to perform a challenging mission capability at the SoS level. While these multiple levels represent layers of physical abstraction, each discipline is associated with tools of varying fidelity forming strata of 'analysis abstraction'. Further, the design (composition) will be guided by a suitable hierarchical complexity metric formulated for the management of complexity in both the problem (as part of the generative procedure and selection of fidelity level) and the product (i.e., is the mission

  1. Electric-Power System Simulator

    NASA Technical Reports Server (NTRS)

    Caldwell, R. W.; Grumm, R. L.; Biedebach, B. L.

    1984-01-01

    Shows different combinations of generation, storage, and load components: display, video monitor with keyboard input to microprocessor, and video monitor for display of load curves and power generation. Planning tool for electric utilities, regulatory agencies, and laymen in understanding basics of electric-power systems operation.

  2. Autonomous Robotic Refueling System (ARRS) for rapid aircraft turnaround

    NASA Astrophysics Data System (ADS)

    Williams, O. R.; Jackson, E.; Rueb, K.; Thompson, B.; Powell, K.

    An autonomous robotic refuelling system is being developed to achieve rapid aircraft turnaround, notably during combat operations. The proposed system includes a gantry positioner with sufficient reach to position a robotic arm that performs the refuelling tasks; a six degree of freedom manipulator equipped with a remote center of compliance, torque sensor, and a gripper that can handle standard tools; a computer vision system to locate and guide the refuelling nozzle, inspect the nozzle, and avoid collisions; and an operator interface with video and graphics display. The control system software will include components designed for trajectory planning and generation, collision detection, sensor interfacing, sensory processing, and human interfacing. The robotic system will be designed so that upgrading to perform additional tasks will be relatively straightforward.

  3. Hydrogen Fuel System Design Trades for High-Altitude Long-Endurance Remotely- Operated Aircraft

    NASA Technical Reports Server (NTRS)

    Millis, Marc G.; Tornabene, Robert T.; Jurns, John M.; Guynn, Mark D.; Tomsik, Thomas M.; VanOverbeke, Thomas J.

    2009-01-01

    Preliminary design trades are presented for liquid hydrogen fuel systems for remotely-operated, high-altitude aircraft that accommodate three different propulsion options: internal combustion engines, and electric motors powered by either polymer electrolyte membrane fuel cells or solid oxide fuel cells. Mission goal is sustained cruise at 60,000 ft altitude, with duration-aloft a key parameter. The subject aircraft specifies an engine power of 143 to 148 hp, gross liftoff weight of 9270 to 9450 lb, payload of 440 lb, and a hydrogen fuel capacity of 2650 to 2755 lb stored in two spherical tanks (8.5 ft inside diameter), each with a dry mass goal of 316 lb. Hydrogen schematics for all three propulsion options are provided. Each employs vacuum-jacketed tanks with multilayer insulation, augmented with a helium pressurant system, and using electric motor driven hydrogen pumps. The most significant schematic differences involve the heat exchangers and hydrogen reclamation equipment. Heat balances indicate that mission durations of 10 to 16 days appear achievable. The dry mass for the hydrogen system is estimated to be 1900 lb, including 645 lb for each tank. This tank mass is roughly twice that of the advanced tanks assumed in the initial conceptual vehicle. Control strategies are not addressed, nor are procedures for filling and draining the tanks.

  4. System for indicating fuel-efficient aircraft altitude

    NASA Technical Reports Server (NTRS)

    Gary, B. L. (Inventor)

    1984-01-01

    A method and apparatus are provided for indicating the altitude at which an aircraft should fly so the W/d ratio (weight of the aircraft divided by the density of air) more closely approaches the optimum W/d for the aircraft. A passive microwave radiometer on the aircraft is directed at different angles with respect to the horizon to determine the air temperature, and therefore the density of the air, at different altitudes. The weight of the aircraft is known. The altitude of the aircraft is changed to fly the aircraft at an altitude at which is W/d ratio more closely approaches the optimum W/d ratio for that aircraft.

  5. Next Generation Civil Transport Aircraft Design Considerations for Improving Vehicle and System-Level Efficiency

    NASA Technical Reports Server (NTRS)

    Acosta, Diana M.; Guynn, Mark D.; Wahls, Richard A.; DelRosario, Ruben,

    2013-01-01

    The future of aviation will benefit from research in aircraft design and air transportation management aimed at improving efficiency and reducing environmental impacts. This paper presents civil transport aircraft design trends and opportunities for improving vehicle and system-level efficiency. Aircraft design concepts and the emerging technologies critical to reducing thrust specific fuel consumption, reducing weight, and increasing lift to drag ratio currently being developed by NASA are discussed. Advancements in the air transportation system aimed towards system-level efficiency are discussed as well. Finally, the paper describes the relationship between the air transportation system, aircraft, and efficiency. This relationship is characterized by operational constraints imposed by the air transportation system that influence aircraft design, and operational capabilities inherent to an aircraft design that impact the air transportation system.

  6. Interactive system for quick modeling of aircraft surfaces

    NASA Astrophysics Data System (ADS)

    Mudur, S. P.; Khandekar, Dilip R.

    1990-08-01

    The precise specification of surface geometry of an aircraft is one of the most important and major activities inits design. An initial design, defined by the fundamental requirements, is iteratively analysed and modified till a satisfactory configuration is obtained. Very often in the early stages the need to rapidly make modifications to the geometry for immediate analysis overrides the stringency of smoothness and correctness ofthe surfaces. This paper describes the design of an interactive system which enables the designer to quickly specify the surface geometry and to modify it easily and rapidly. In particular, the software engineering aspects are emphasized. The system uses B-splines for the representation of complex geometry. Surfaces of revolution, required to model certain parts ofthe aircraft, and other simple geometric primitives are also supported. Apart from the usual modeller facilities, features such as camber, twist and form constraints such as tangent or curvature control at a point, etc., are also provided. The system enables easy input and rapid editing of geomeiry through the use of a number of innovative concepts which aim at simplifying and speeding up the man-machine interaction. Multiple window display of entities, augmented by plots of curvature, cross sections etc. provide the visualization tool necessary to assist the designer in decision making.

  7. Energy Absorbing Seat System for an Agricultural Aircraft

    NASA Technical Reports Server (NTRS)

    Kellas, Sotiris; Jones, Lisa E. (Technical Monitor)

    2002-01-01

    A task was initiated to improve the energy absorption capability of an existing aircraft seat through cost-effective retrofitting, while keeping seat-weight increase to a minimum. This task was undertaken as an extension of NASA ongoing safety research and commitment to general aviation customer needs. Only vertical crash scenarios have been considered in this task which required the energy absorbing system to protect the seat occupant in a range of crash speeds up to 31 ft/sec. It was anticipated that, the forward and/or side crash accelerations could be attenuated with the aid of airbags, the technology of which is currently available in automobiles and military helicopters. Steps which were followed include, preliminary crush load determination, conceptual design of cost effective energy absorbers, fabrication and testing (static and dynamic) of energy absorbers, system analysis, design and fabrication of dummy seat/rail assembly, dynamic testing of dummy seat/rail assembly, and finally, testing of actual modified seat system with a dummy occupant. A total of ten full scale tests have been performed including three of the actual aircraft seat. Results from full-scale tests indicated that occupant loads were attenuated successfully to survivable levels.

  8. Mobile HTS SQUID System for Nondestructive Evaluation of Aircraft Structures

    NASA Astrophysics Data System (ADS)

    Krause, Hans-Joachim; Hohmann, Rainer; Grueneklee, Michael; Zhang, Yi; Braginski, Alex I.

    1997-03-01

    For the detection of deep-lying flaws in aircraft structures, a mobile eddy-current system is being developed in conjunction with a high-temperature superconductor (Yba_2Cu_3O_7) thin-film HTS SQUID gradiometer. The challenge is to operate the SQUID sensor during movement in strong ambient fields, independent of orientation. A planar rf double hole gradiometer with a gradient sensitivity of 500 fT/(cm √Hz) was designed for that purpose. Two different cooling concepts were successfully implemented: the SQUID operation in the vacuum region of a lightweight nitrogen cryostat, constructed for operation in any orientation, and the use of a commercial Joule-Thomson cryocooler for liquid-nitrogen-free SQUID cooling. With a SQUID integration scheme using a sapphire cold finger, motion-related additional noise is nearly eliminated. Using a system equipped with a differential eddy current excitation, two-dimensional scans were performed to find fatigue cracks and corrosion pits hidden below several layers of aluminum. For demonstration in the Lufthansa maintenance facility at Frankfurt Airport, the system was used to detect flaws in aircraft wheels. Work in progress includes developing longer base gradiometers for detection of deep flaws.

  9. Advanced Propulsion System Studies for General Aviation Aircraft

    NASA Technical Reports Server (NTRS)

    Eisenberg, Joseph D. (Technical Monitor); German, Jon

    2003-01-01

    This final report addresses the following topics: Market Impact Analysis (1) assessment of general aviation, including commuter/regional, aircraft market impact due to incorporation of advanced technology propulsion system on acquisition and operating costs, job creation and/or manpower demand, and future fleet size; (2) selecting an aircraft and engine for the study by focusing on the next generation 19-passenger commuter and the Williams International FJ44 turbofan engine growth. Propulsion System Analysis Conducted mission analysis studies and engine cycle analysis to define a new commuter mission and required engine performance, define acquisition and operating costs and, select engine configuration and initiated preliminary design for hardware modifications required. Propulsion System Benefits (1) assessed and defined engine emissions improvements, (2) assessed and defined noise reduction potential and, (3) conducted a cost analysis impact study. Review of Relevant NASA Programs Conducted literature searches using NERAC and NASA RECON services for related technology in the emissions and acoustics area. Preliminary Technology Development Plans Defined plan to incorporate technology improvements for an FJ44-2 growth engine in performance, emissions, and noise suppression.

  10. ADAM: An Axisymmetric Duct Aeroacoustic Modeling system. [aircraft turbofan engines

    NASA Technical Reports Server (NTRS)

    Abrahamson, A. L.

    1983-01-01

    An interconnected system of computer programs for analyzing the propagation and attenuation of sound in aeroengine ducts containing realistic compressible subsonic mean flows, ADAM was developed primarily for research directed towards the reduction of noise emitted from turbofan aircraft engines. The two basic components are a streamtube curvature program for determination of the mean flow, and a finite element code for solution of the acoustic propagation problem. The system, which has been specifically tailored for ease of use, is presently installed at NASA Langley Reseach Center on a Control Data Cyber 175 Computer under the NOS Operating system employing a Tektronix terminal for interactive graphics. The scope and organization of the ADAM system is described. A users guide, examples of input data, and results for selected cases are included.

  11. Smart Sensor System for NDE or Corrosion in Aging Aircraft

    NASA Technical Reports Server (NTRS)

    Bar-Cohen, Y.; Marzwell, N.; Osegueda, R.; Ferregut, C.

    1998-01-01

    The extension of the operation life of military and civilian aircraft rather than replacing them with new ones is increasing the probability of aircraft component failure as a result of aging. Aircraft that already have endured a long srvice life of more than 40 years are now being considered for another 40 years of service.

  12. The Typical General Aviation Aircraft

    NASA Technical Reports Server (NTRS)

    Turnbull, Andrew

    1999-01-01

    The reliability of General Aviation aircraft is unknown. In order to "assist the development of future GA reliability and safety requirements", a reliability study needs to be performed. Before any studies on General Aviation aircraft reliability begins, a definition of a typical aircraft that encompasses most of the general aviation characteristics needs to be defined. In this report, not only is the typical general aviation aircraft defined for the purpose of the follow-on reliability study, but it is also separated, or "sifted" into several different categories where individual analysis can be performed on the reasonably independent systems. In this study, the typical General Aviation aircraft is a four-place, single engine piston, all aluminum fixed-wing certified aircraft with a fixed tricycle landing gear and a cable operated flight control system. The system breakdown of a GA aircraft "sifts" the aircraft systems and components into five categories: Powerplant, Airframe, Aircraft Control Systems, Cockpit Instrumentation Systems, and the Electrical Systems. This breakdown was performed along the lines of a failure of the system. Any component that caused a system to fail was considered a part of that system.

  13. A knowledge-based system design/information tool for aircraft flight control systems

    NASA Technical Reports Server (NTRS)

    Mackall, Dale A.; Allen, James G.

    1989-01-01

    Research aircraft have become increasingly dependent on advanced control systems to accomplish program goals. These aircraft are integrating multiple disciplines to improve performance and satisfy research objectives. This integration is being accomplished through electronic control systems. Because of the number of systems involved and the variety of engineering disciplines, systems design methods and information management have become essential to program success. The primary objective of the system design/information tool for aircraft flight control system is to help transfer flight control system design knowledge to the flight test community. By providing all of the design information and covering multiple disciplines in a structured, graphical manner, flight control systems can more easily be understood by the test engineers. This will provide the engineers with the information needed to thoroughly ground test the system and thereby reduce the likelihood of serious design errors surfacing in flight. The secondary objective is to apply structured design techniques to all of the design domains. By using the techniques in the top level system design down through the detailed hardware and software designs, it is hoped that fewer design anomalies will result. The flight test experiences of three highly complex, integrated aircraft programs are reviewed: the X-29 forward-swept wing, the advanced fighter technology integration (AFTI) F-16, and the highly maneuverable aircraft technology (HiMAT) program. Significant operating anomalies and the design errors which cause them, are examined to help identify what functions a system design/information tool should provide to assist designers in avoiding errors.

  14. Review of the FOCSI (Fiber Optic Control System Integration) program. [applications in aircraft flight control

    NASA Technical Reports Server (NTRS)

    Baumbick, Robert

    1991-01-01

    A joint NASA/NAVY program, called FOCSI, is reviewed which is aimed at designing optical sensor systems to fit the installation and environmentally test passive optical sensors and electrooptic architectures. These optical sensor systems will be flown on an F18 aircraft to collect data on the operability and maintainability of these systems in a flight environment. The NASA F-18 aircraft will be equipped with a 1773 optical databus to transfer the optical sensor information to the aircraft data collection location.

  15. Evaluation of Mobile Phone Interference With Aircraft GPS Navigation Systems

    NASA Technical Reports Server (NTRS)

    Pace, Scott; Oria, A. J.; Guckian, Paul; Nguyen, Truong X.

    2004-01-01

    This report compiles and analyzes tests that were conducted to measure cell phone spurious emissions in the Global Positioning System (GPS) radio frequency band that could affect the navigation system of an aircraft. The cell phone in question had, as reported to the FAA (Federal Aviation Administration), caused interference to several GPS receivers on-board a small single engine aircraft despite being compliant with data filed at the time with the FCC by the manufacturer. NASA (National Aeronautics and Space Administration) and industry tests show that while there is an emission in the 1575 MHz GPS band due to a specific combination of amplifier output impedance and load impedance that induces instability in the power amplifier, these spurious emissions (i.e., not the intentional transmit signal) are similar to those measured on non-intentionally transmitting devices such as, for example, laptop computers. Additional testing on a wide sample of different commercial cell phones did not result in any emission in the 1575 MHz GPS Band above the noise floor of the measurement receiver.

  16. Modeling Pilot State in Next Generation Aircraft Alert Systems

    NASA Technical Reports Server (NTRS)

    Carlin, Alan S.; Alexander, Amy L.; Schurr, Nathan

    2011-01-01

    The Next Generation Air Transportation System will introduce new, advanced sensor technologies into the cockpit that must convey a large number of potentially complex alerts. Our work focuses on the challenges associated with prioritizing aircraft sensor alerts in a quick and efficient manner, essentially determining when and how to alert the pilot This "alert decision" becomes very difficult in NextGen due to the following challenges: 1) the increasing number of potential hazards, 2) the uncertainty associated with the state of potential hazards as well as pilot slate , and 3) the limited time to make safely-critical decisions. In this paper, we focus on pilot state and present a model for anticipating duration and quality of pilot behavior, for use in a larger system which issues aircraft alerts. We estimate pilot workload, which we model as being dependent on factors including mental effort, task demands. and task performance. We perform a mathematically rigorous analysis of the model and resulting alerting plans. We simulate the model in software and present simulated results with respect to manipulation of the pilot measures.

  17. Fan Noise Prediction with Applications to Aircraft System Noise Assessment

    NASA Technical Reports Server (NTRS)

    Nark, Douglas M.; Envia, Edmane; Burley, Casey L.

    2009-01-01

    This paper describes an assessment of current fan noise prediction tools by comparing measured and predicted sideline acoustic levels from a benchmark fan noise wind tunnel test. Specifically, an empirical method and newly developed coupled computational approach are utilized to predict aft fan noise for a benchmark test configuration. Comparisons with sideline noise measurements are performed to assess the relative merits of the two approaches. The study identifies issues entailed in coupling the source and propagation codes, as well as provides insight into the capabilities of the tools in predicting the fan noise source and subsequent propagation and radiation. In contrast to the empirical method, the new coupled computational approach provides the ability to investigate acoustic near-field effects. The potential benefits/costs of these new methods are also compared with the existing capabilities in a current aircraft noise system prediction tool. The knowledge gained in this work provides a basis for improved fan source specification in overall aircraft system noise studies.

  18. System Synthesis in Preliminary Aircraft Design using Statistical Methods

    NASA Technical Reports Server (NTRS)

    DeLaurentis, Daniel; Mavris, Dimitri N.; Schrage, Daniel P.

    1996-01-01

    This paper documents an approach to conceptual and preliminary aircraft design in which system synthesis is achieved using statistical methods, specifically design of experiments (DOE) and response surface methodology (RSM). These methods are employed in order to more efficiently search the design space for optimum configurations. In particular, a methodology incorporating three uses of these techniques is presented. First, response surface equations are formed which represent aerodynamic analyses, in the form of regression polynomials, which are more sophisticated than generally available in early design stages. Next, a regression equation for an overall evaluation criterion is constructed for the purpose of constrained optimization at the system level. This optimization, though achieved in a innovative way, is still traditional in that it is a point design solution. The methodology put forward here remedies this by introducing uncertainty into the problem, resulting a solutions which are probabilistic in nature. DOE/RSM is used for the third time in this setting. The process is demonstrated through a detailed aero-propulsion optimization of a high speed civil transport. Fundamental goals of the methodology, then, are to introduce higher fidelity disciplinary analyses to the conceptual aircraft synthesis and provide a roadmap for transitioning from point solutions to probabalistic designs (and eventually robust ones).

  19. System Synthesis in Preliminary Aircraft Design Using Statistical Methods

    NASA Technical Reports Server (NTRS)

    DeLaurentis, Daniel; Mavris, Dimitri N.; Schrage, Daniel P.

    1996-01-01

    This paper documents an approach to conceptual and early preliminary aircraft design in which system synthesis is achieved using statistical methods, specifically Design of Experiments (DOE) and Response Surface Methodology (RSM). These methods are employed in order to more efficiently search the design space for optimum configurations. In particular, a methodology incorporating three uses of these techniques is presented. First, response surface equations are formed which represent aerodynamic analyses, in the form of regression polynomials, which are more sophisticated than generally available in early design stages. Next, a regression equation for an Overall Evaluation Criterion is constructed for the purpose of constrained optimization at the system level. This optimization, though achieved in an innovative way, is still traditional in that it is a point design solution. The methodology put forward here remedies this by introducing uncertainty into the problem, resulting in solutions which are probabilistic in nature. DOE/RSM is used for the third time in this setting. The process is demonstrated through a detailed aero-propulsion optimization of a High Speed Civil Transport. Fundamental goals of the methodology, then, are to introduce higher fidelity disciplinary analyses to the conceptual aircraft synthesis and provide a roadmap for transitioning from point solutions to probabilistic designs (and eventually robust ones).

  20. Aircraft voice intercommunications system design for Project Oculus

    NASA Astrophysics Data System (ADS)

    Wilhelm, Jay; Smith, James E.

    2006-05-01

    Project Oculus, an ongoing research platform for deploying airborne sensors on a C-130 aircraft, is currently in its pre-flight testing phase. The sensor platform is divided into two systems that rest on standard 463L pallets; a sensor deployment pallet and an operator station. The sensor pallet consists of a deployment arm and a pod, which can contain various sensors. The operator station houses power control equipment, data acquisition, and operators who control the sensors. Oculus is designed to fly on a C-130 aircraft, which has very high internal audible noise. Although Oculus' operator station contains noise-deadening material, a headset intercommunication system needs to be designed. This system must comply with different headset standards, communicate with the C-130 intercom, and be expandable to accommodate various audio sources like radios and satellites receivers. Throughout the years, intercom systems and headsets have evolved from the original standard consisting of an impedance rating of a speaker and a microphone. Early intercom systems were highly limited in functionality and quality due to simple electronics and common grounding. Advances in electronics allowed for the evolution of headset standards and intercom equipment, which permitted a multitude of new configurations and improved sound quality. With these advances, multiple headset standards and intercom interfaces have become popular among the military and civilian aviation. Due to the different standards for headsets, impedance matching plays a major role in the design of an intercom system. Oculus is a multi-mission platform and therefore must be designed to support a variety of standards including civilian and military headsets. This paper outlines the intercom units and parts considered for use in Oculus, and a design criteria for an extendable intercom system for Oculus.

  1. Fault tolerant architectures for integrated aircraft electronics systems, task 2

    NASA Technical Reports Server (NTRS)

    Levitt, K. N.; Melliar-Smith, P. M.; Schwartz, R. L.

    1984-01-01

    The architectural basis for an advanced fault tolerant on-board computer to succeed the current generation of fault tolerant computers is examined. The network error tolerant system architecture is studied with particular attention to intercluster configurations and communication protocols, and to refined reliability estimates. The diagnosis of faults, so that appropriate choices for reconfiguration can be made is discussed. The analysis relates particularly to the recognition of transient faults in a system with tasks at many levels of priority. The demand driven data-flow architecture, which appears to have possible application in fault tolerant systems is described and work investigating the feasibility of automatic generation of aircraft flight control programs from abstract specifications is reported.

  2. A knowledge-based system design/information tool for aircraft flight control systems

    NASA Technical Reports Server (NTRS)

    Mackall, Dale A.; Allen, James G.

    1991-01-01

    Research aircraft have become increasingly dependent on advanced electronic control systems to accomplish program goals. These aircraft are integrating multiple disciplines to improve performance and satisfy research objective. This integration is being accomplished through electronic control systems. Systems design methods and information management have become essential to program success. The primary objective of the system design/information tool for aircraft flight control is to help transfer flight control system design knowledge to the flight test community. By providing all of the design information and covering multiple disciplines in a structured, graphical manner, flight control systems can more easily be understood by the test engineers. This will provide the engineers with the information needed to thoroughly ground test the system and thereby reduce the likelihood of serious design errors surfacing in flight. The secondary object is to apply structured design techniques to all of the design domains. By using the techniques in the top level system design down through the detailed hardware and software designs, it is hoped that fewer design anomalies will result. The flight test experiences are reviewed of three highly complex, integrated aircraft programs: the X-29 forward swept wing; the advanced fighter technology integration (AFTI) F-16; and the highly maneuverable aircraft technology (HiMAT) program. Significant operating technologies, and the design errors which cause them, is examined to help identify what functions a system design/informatin tool should provide to assist designers in avoiding errors.

  3. Electric fields, conductivity, and estimated currents from aircraft overflights of electrified clouds

    NASA Astrophysics Data System (ADS)

    Mach, Douglas M.; Blakeslee, Richard J.; Bateman, Monte G.; Bailey, Jeffrey C.

    2009-05-01

    Using rotating vane electric field mills and Gerdien capacitors, we measured the electric field profile and conductivity during 850 overflights of clouds and thunderstorms. The measurements were made with NASA ER-2 and Altus-II aircrafts. Peak electric fields, with lightning transients removed, ranged from -1.0 kV m-1 to 16. kV m-1, with a mean value of 0.9 kV m-1. The median peak field was 0.29 kV m-1. Flash rates ranged from 0 to over 27 flashes min-1 with the mean flash rate of 1.2 flashes min-1. The median flash rate for an overpass was 0.25 flashes min-1. The positive plus negative conductivity ranged from 0.6 pS m-1 to 3.6 pS m-1 at the nominal flight altitudes of 15 to 20 km. The mean and median total conductivity was 2.2 pS m-1. Peak current densities during the overpasses ranged from -2.0 nA m-2 to 33. nA m-2. The mean peak current density was 1.9 nA m-2, and the median value was 0.6 nA m-2. Using the peak electric fields, a median field falloff with distance based on all overflights, and cylindrical storm symmetry, the total upward current flow from storms in our data set ranges from -1.3 to 9.4 A with a mean value of 0.8 A. The median total current was 0.27 A. The contributions from lightning field changes do not significantly affect the total derived currents. We found that 7% of the storms were producing current flows above the storms that were opposite in polarity from the standard role that thunderstorms play in the global electric circuit. Approximately one third of the storms had no detectable lightning during the overpasses but still had significant electric fields. Owing to a possible sampling bias, the fraction of nonlightning storms with electric fields may not reflect the global probability of these clouds.

  4. Demand for large freighter aircraft as projected by the NASA cargo/logistics airlift systems studies

    NASA Technical Reports Server (NTRS)

    Whitehead, A. H., Jr.; Kuhlman, W. H.

    1979-01-01

    This paper examines the market conditions up through the year 2008 to provide a preliminary assessment of the potential for and the characteristics of an advanced, all-cargo transport aircraft. Any new freighter must compete with current wide-body aircraft and their derivatives. Aircraft larger than the wide-bodies may incur economic penalties and operational problems. A lower direct operating cost is not a sufficient criterion to base a decision for the initiation of a new aircraft development or to select aircraft characteristics. Other factors of equal importance that are reviewed in this paper include considerations of the system infrastructure, the economics of the airlines, and the aircraft manufacturer return on investment. The results of the market forecast and a computer simulation show that an advanced long range aircraft with a payload between 68 to 181 tonnes (75 to 200 tons) could generate a solid foothold beginning around 1994.

  5. Demand for large freighter aircraft as projected by the NASA cargo/logistics airlift system studies

    NASA Technical Reports Server (NTRS)

    Whitehead, A. H., Jr.; Kuhlman, W. H.

    1979-01-01

    The market conditions are examined up through the year 2008 to provide a preliminary assessment of the potential for and the characteristics of an advanced, all-cargo transport aircraft. Any new freighter must compete with current wide-body aircraft and their derivatives. Aircraft larger than the wide-bodies may incur economic penalties and operational problems. A lower direct operating cost is not a sufficient criterion to base a decision for the initiation of a new aircraft development or to select aircraft characteristics. Other factors of equal importance that are reviewed in this paper include considerations of the system infrastructure, the economics of the airlines, and the aircraft manufacturer return on investment. The results of the market forecast and a computer simulation show that an advanced long range aircraft with a payload between 68 to 181 tonnes (75 to 200 tons) could generate a solid foothold beginning around 1994.

  6. Characterisation of a hybrid, fuel-cell-based propulsion system for small unmanned aircraft

    NASA Astrophysics Data System (ADS)

    Verstraete, D.; Lehmkuehler, K.; Gong, A.; Harvey, J. R.; Brian, G.; Palmer, J. L.

    2014-03-01

    Advanced hybrid powerplants combining a fuel cell and battery can enable significantly higher endurance for small, electrically powered unmanned aircraft systems, compared with batteries alone. However, detailed investigations of the static and dynamic performance of such systems are required to address integration challenges. This article describes a series of tests used to characterise the Horizon Energy Systems' AeroStack hybrid, fuel-cell-based powertrain. The results demonstrate that a significant difference can exist between the dynamic performance of the fuel-cell system and its static polarisation curve, confirming the need for detailed measurements. The results also confirm that the AeroStack's lithium-polymer battery plays a crucial role in its response to dynamic load changes and protects the fuel cell from membrane dehydration and fuel starvation. At low static loads, the AeroStack fuel cell recharges the battery with currents up to 1 A, which leads to further differences with the polarisation curve.

  7. Neural network application to aircraft control system design

    NASA Technical Reports Server (NTRS)

    Troudet, Terry; Garg, Sanjay; Merrill, Walter C.

    1991-01-01

    The feasibility of using artificial neural network as control systems for modern, complex aerospace vehicles is investigated via an example aircraft control design study. The problem considered is that of designing a controller for an integrated airframe/propulsion longitudinal dynamics model of a modern fighter aircraft to provide independent control of pitch rate and airspeed responses to pilot command inputs. An explicit model following controller using H infinity control design techniques is first designed to gain insight into the control problem as well as to provide a baseline for evaluation of the neurocontroller. Using the model of the desired dynamics as a command generator, a multilayer feedforward neural network is trained to control the vehicle model within the physical limitations of the actuator dynamics. This is achieved by minimizing an objective function which is a weighted sum of tracking errors and control input commands and rates. To gain insight in the neurocontrol, linearized representations of the nonlinear neurocontroller are analyzed along a commanded trajectory. Linear robustness analysis tools are then applied to the linearized neurocontroller models and to the baseline H infinity based controller. Future areas of research identified to enhance the practical applicability of neural networks to flight control design.

  8. Neural network application to aircraft control system design

    NASA Technical Reports Server (NTRS)

    Troudet, Terry; Garg, Sanjay; Merrill, Walter C.

    1991-01-01

    The feasibility of using artificial neural networks as control systems for modern, complex aerospace vehicles is investigated via an example aircraft control design study. The problem considered is that of designing a controller for an integrated airframe/propulsion longitudinal dynamics model of a modern fighter aircraft to provide independent control of pitch rate and airspeed responses to pilot command inputs. An explicit model following controller using H infinity control design techniques is first designed to gain insight into the control problem as well as to provide a baseline for evaluation of the neurocontroller. Using the model of the desired dynamics as a command generator, a multilayer feedforward neural network is trained to control the vehicle model within the physical limitations of the actuator dynamics. This is achieved by minimizing an objective function which is a weighted sum of tracking errors and control input commands and rates. To gain insight in the neurocontrol, linearized representations of the nonlinear neurocontroller are analyzed along a commanded trajectory. Linear robustness analysis tools are then applied to the linearized neurocontroller models and to the baseline H infinity based controller. Future areas of research are identified to enhance the practical applicability of neural networks to flight control design.

  9. Autonomous Flight Safety System September 27, 2005, Aircraft Test

    NASA Technical Reports Server (NTRS)

    Simpson, James C.

    2005-01-01

    This report describes the first aircraft test of the Autonomous Flight Safety System (AFSS). The test was conducted on September 27, 2005, near Kennedy Space Center (KSC) using a privately-owned single-engine plane and evaluated the performance of several basic flight safety rules using real-time data onboard a moving aerial vehicle. This test follows the first road test of AFSS conducted in February 2005 at KSC. AFSS is a joint KSC and Wallops Flight Facility (WEF) project that is in its third phase of development. AFSS is an independent subsystem intended for use with Expendable Launch Vehicles that uses tracking data from redundant onboard sensors to autonomously make flight termination decisions using software-based rules implemented on redundant flight processors. The goals of this project are to increase capabilities by allowing launches from locations that do not have or cannot afford extensive ground-based range safety assets, to decrease range costs, and to decrease reaction time for special situations. The mission rules are configured for each operation by the responsible Range Safety authorities and can be loosely categorized in four major categories: Parameter Threshold Violations, Physical Boundary Violations present position and instantaneous impact point (TIP), Gate Rules static and dynamic, and a Green-Time Rule. Examples of each of these rules were evaluated during this aircraft test.

  10. Wide field of view laser beacon system for three dimensional aircraft range measurements

    NASA Technical Reports Server (NTRS)

    Wong, E. Y.

    1982-01-01

    A system that measures accurately the distance from an aircraft to a helicoper for rotor noise flight testing was developed. The system measures the range and angles between two aircraft using laser optics. This system can be applied in collision avoidance, robotics and other measurement critical tasks.

  11. Laser Doppler velocimeter system simulation for sensing aircraft wake vortices

    NASA Technical Reports Server (NTRS)

    Thomson, J. A. L.; Meng, J. C. S.

    1974-01-01

    A hydrodynamic model of aircraft vortex wakes in an irregular wind shear field near the ground is developed and used as a basis for modeling the characteristics of a laser Doppler detection and vortex location system. The trailing vortex sheet and the wind shear are represented by discrete free vortices distributed over a two-dimensional grid. The time dependent hydrodynamic equations are solved by direct numerical integration in the Boussinesq approximation. The ground boundary is simulated by images, and fast Fourier Transform techniques are used to evaluate the vorticity stream function. The atmospheric turbulence was simulated by constructing specific realizations at time equal to zero, assuming that Kolmogoroff's law applies, and that the dissipation rate is constant throughout the flow field. The response of a simulated laser Doppler velocimeter is analyzed by simulating the signal return from the flow field as sensed by a simulation of the optical/electronic system.

  12. TRUSS: An intelligent design system for aircraft wings

    NASA Technical Reports Server (NTRS)

    Bates, Preston R.; Schrage, Daniel P.

    1989-01-01

    Competitive leadership in the international marketplace, superiority in national defense, excellence in productivity, and safety of both private and public systems are all national defense goals which are dependent on superior engineering design. In recent years, it has become more evident that early design decisions are critical, and when only based on performance often result in products which are too expensive, hard to manufacture, or unsupportable. Better use of computer-aided design tools and information-based technologies is required to produce better quality United States products. A program is outlined here to explore the use of knowledge based expert systems coupled with numerical optimization, database management techniques, and designer interface methods in a networked design environment to improve and assess design changes due to changing emphasis or requirements. The initial structural design of a tiltrotor aircraft wing is used as a representative example to demonstrate the approach being followed.

  13. CID-720 aircraft high-environment flight instrumentation system

    NASA Technical Reports Server (NTRS)

    Calloway, R. S.

    1986-01-01

    The high-environment flight instrumentation system was designed to acquire Langley's structural response data during the full scale transport-controlled impact demonstration test. There was only one opportunity for data acquisition. Thus, a high reliability and crashworthy design approach was implemented. The approach featured multi-level redundancy and a vigorous quality assurance testing program. Complying with an accelerated schedule, the instrumentation system was developed, tested and shipped within 18 months to Dryden Flight Research Facility. The flight instrumentation system consists of two autonomous data systems, DAS #1 and #2, and an excellent checkout subsystem. Each data system is partitioned into four pallets. The system was designed to operate on manned and unmanned flights. There are 176 data channels per data system. These channels are sequentially sampled and encoded into 1 megabit/sec pulse code modulation (PCM) data signal. To increase the probability of success, a special PCM distribution subsystem was developed. This subsystem distributes the PCM signal to two transmitters, one delay memory, and eight recorder tracks. The data on four of these trackes was digitally delayed approximately 300 msec to maximize data acquisition during impact. Therefore each data system's data is redundantly recorded onboard and on the ground. There are two time code generators. Parallel time from each is encoded into both data systems. Serial time from each is redundantly recorded on both onboard recorders. Instrumentation power is independent of aircraft power and self-contained.

  14. Advanced piloted aircraft flight control system design methodology. Volume 1: Knowledge base

    NASA Technical Reports Server (NTRS)

    Mcruer, Duane T.; Myers, Thomas T.

    1988-01-01

    The development of a comprehensive and electric methodology for conceptual and preliminary design of flight control systems is presented and illustrated. The methodology is focused on the design stages starting with the layout of system requirements and ending when some viable competing system architectures (feedback control structures) are defined. The approach is centered on the human pilot and the aircraft as both the sources of, and the keys to the solution of, many flight control problems. The methodology relies heavily on computational procedures which are highly interactive with the design engineer. To maximize effectiveness, these techniques, as selected and modified to be used together in the methodology, form a cadre of computational tools specifically tailored for integrated flight control system preliminary design purposes. While theory and associated computational means are an important aspect of the design methodology, the lore, knowledge and experience elements, which guide and govern applications are critical features. This material is presented as summary tables, outlines, recipes, empirical data, lists, etc., which encapsulate a great deal of expert knowledge. Much of this is presented in topical knowledge summaries which are attached as Supplements. The composite of the supplements and the main body elements constitutes a first cut at a a Mark 1 Knowledge Base for manned-aircraft flight control.

  15. Nuclear electric propulsion systems overview

    NASA Technical Reports Server (NTRS)

    Doherty, Michael P.

    1993-01-01

    The topics are presented in viewgraph form and include the following: nuclear propulsion background; schedule for the nuclear electric propulsion (NEP) project; NEP for the Space Exploration Initiative; NEP on-going systems tasks; 20KWe mission/system study; and agenda.

  16. Comparison of piezoelectric systems and aerodynamic systems for aircraft vibration alleviation

    NASA Astrophysics Data System (ADS)

    Becker, Juergen; Luber, Wolfgang G.

    1998-06-01

    A comparison of active smart structure - piezoelectric control system and aerodynamic active systems for vibration alleviation and elastic mode damping of a military aircraft structure is presented. The vibration alleviation systems which are operative at flight in turbulence or during maneuvers at high incidence corresponding to severe buffeting conditions are under investigation by DASA as a part of research study on advanced aircraft structures. The active systems for elastic mode damping are designed as digital systems to provide vibration alleviation and have an interface to the flight control system (FCS) or are directly part of the FCS. The sensor concept of all different systems is the same as the sensor concept used for the FCS with the corresponding benefits of redundancy and safety. The design of systems and the comparisons of system properties are based on open and closed loop response calculations, performed with the dynamic model of the total aircraft including coupling of flight mechanics, structural dynamics, FCS dynamics and hydraulic actuator or piezo-actuator dynamics. Aerodynamic systems, like active foreplane and flap concepts, rudder and auxiliary rudder concepts, and piezoelectric systems, like piezo interface at the interconnection fin to rear fuselage and integrated piezo concepts are compared. Besides the essential effects on flexible aircraft mode stability and vibration alleviation factors system complexity and safety aspects are described.

  17. Rotor systems research aircraft predesign study. Volume 3: Predesign report

    NASA Technical Reports Server (NTRS)

    Schmidt, S. A.; Linden, A. W.

    1972-01-01

    The features of two aircraft designs were selected to be included in the single RSRA configuration. A study was conducted for further preliminary design and a more detailed analysis of development plans and costs. An analysis was also made of foreseeable technical problems and risks, identification of parallel research which would reduce risks and/or add to the basic capability of the aircraft, and a draft aircraft specification.

  18. Electrical power generating system

    NASA Technical Reports Server (NTRS)

    Nola, F. J. (Inventor)

    1983-01-01

    A power generating system for adjusting coupling an induction motor, as a generator, to an A.C. power line wherein the motor and power line are connected through a triac is described. The triac is regulated to normally turn on at a relatively late point in each half cycle of its operation, whereby at less than operating speed, and thus when the induction motor functions as a motor rather than as a generator, power consumption from the line is substantially reduced.

  19. An integrated systems engineering approach to aircraft design

    NASA Astrophysics Data System (ADS)

    Price, M.; Raghunathan, S.; Curran, R.

    2006-06-01

    The challenge in Aerospace Engineering, in the next two decades as set by Vision 2020, is to meet the targets of reduction of nitric oxide emission by 80%, carbon monoxide and carbon dioxide both by 50%, reduce noise by 50% and of course with reduced cost and improved safety. All this must be achieved with expected increase in capacity and demand. Such a challenge has to be in a background where the understanding of physics of flight has changed very little over the years and where industrial growth is driven primarily by cost rather than new technology. The way forward to meet the challenges is to introduce innovative technologies and develop an integrated, effective and efficient process for the life cycle design of aircraft, known as systems engineering (SE). SE is a holistic approach to a product that comprises several components. Customer specifications, conceptual design, risk analysis, functional analysis and architecture, physical architecture, design analysis and synthesis, and trade studies and optimisation, manufacturing, testing validation and verification, delivery, life cycle cost and management. Further, it involves interaction between traditional disciplines such as Aerodynamics, Structures and Flight Mechanics with people- and process-oriented disciplines such as Management, Manufacturing, and Technology Transfer. SE has become the state-of-the-art methodology for organising and managing aerospace production. However, like many well founded methodologies, it is more difficult to embody the core principles into formalised models and tools. The key contribution of the paper will be to review this formalisation and to present the very latest knowledge and technology that facilitates SE theory. Typically, research into SE provides a deeper understanding of the core principles and interactions, and helps one to appreciate the required technical architecture for fully exploiting it as a process, rather than a series of events. There are major issues as

  20. Small Engine Technology (SET) Task 24 Business and Regional Aircraft System Studies

    NASA Technical Reports Server (NTRS)

    Lieber, Lysbeth

    2003-01-01

    This final report has been prepared by Honeywell Engines & Systems, Phoenix, Arizona, a unit of Honeywell International Inc., documenting work performed during the period June 1999 through December 1999 for the National Aeronautics and Space Administration (NASA) Glenn Research Center, Cleveland, Ohio, under the Small Engine Technology (SET) Program, Contract No. NAS3-27483, Task Order 24, Business and Regional Aircraft System Studies. The work performed under SET Task 24 consisted of evaluating the noise reduction benefits compared to the baseline noise levels of representative 1992 technology aircraft, obtained by applying different combinations of noise reduction technologies to five business and regional aircraft configurations. This report focuses on the selection of the aircraft configurations and noise reduction technologies, the prediction of noise levels for those aircraft, and the comparison of the noise levels with those of the baseline aircraft.

  1. Electrical power systems for Mars

    NASA Technical Reports Server (NTRS)

    Giudici, Robert J.

    1986-01-01

    Electrical power system options for Mars Manned Modules and Mars Surface Bases were evaluated for both near-term and advanced performance potential. The power system options investigated for the Mission Modules include photovoltaics, solar thermal, nuclear reactor, and isotope power systems. Options discussed for Mars Bases include the above options with the addition of a brief discussion of open loop energy conversion of Mars resources, including utilization of wind, subsurface thermal gradients, and super oxides. Electrical power requirements for Mission Modules were estimated for three basic approaches: as a function of crew size; as a function of electric propulsion; and as a function of transmission of power from an orbiter to the surface of Mars via laser or radio frequency. Mars Base power requirements were assumed to be determined by production facilities that make resources available for follow-on missions leading to the establishment of a permanently manned Base. Requirements include the production of buffer gas and propellant production plants.

  2. Electrical power systems for Mars

    NASA Astrophysics Data System (ADS)

    Giudici, Robert J.

    1986-05-01

    Electrical power system options for Mars Manned Modules and Mars Surface Bases were evaluated for both near-term and advanced performance potential. The power system options investigated for the Mission Modules include photovoltaics, solar thermal, nuclear reactor, and isotope power systems. Options discussed for Mars Bases include the above options with the addition of a brief discussion of open loop energy conversion of Mars resources, including utilization of wind, subsurface thermal gradients, and super oxides. Electrical power requirements for Mission Modules were estimated for three basic approaches: as a function of crew size; as a function of electric propulsion; and as a function of transmission of power from an orbiter to the surface of Mars via laser or radio frequency. Mars Base power requirements were assumed to be determined by production facilities that make resources available for follow-on missions leading to the establishment of a permanently manned Base. Requirements include the production of buffer gas and propellant production plants.

  3. Conceptual design of an aircraft automated coating removal system

    SciTech Connect

    Baker, J.E.; Draper, J.V.; Pin, F.G.; Primm, A.H.; Shekhar, S.

    1996-05-01

    Paint stripping of the U.S. Air Force`s large transport aircrafts is currently a labor-intensive, manual process. Significant reductions in costs, personnel and turnaround time can be accomplished by the judicious use of automation in some process tasks. This paper presents the conceptual design of a coating removal systems for the tail surfaces of the C-5 plane. Emphasis is placed on the technology selection to optimize human-automation synergy with respect to overall costs, throughput, quality, safety, and reliability. Trade- offs between field-proven vs. research-requiring technologies, and between expected gain vs. cost and complexity, have led to a conceptual design which is semi-autonomous (relying on the human for task specification and disturbance handling) yet incorporates sensor- based automation (for sweep path generation and tracking, surface following, stripping quality control and tape/breach handling).

  4. Fuel property effects on Navy aircraft fuel systems

    NASA Technical Reports Server (NTRS)

    Moses, C. A.

    1984-01-01

    Problems of ensuring compatibility of Navy aircraft with fuels that may be different than the fuels for which the equipment was designed and qualified are discussed. To avoid expensive requalification of all the engines and airframe fuel systems, methodologies to qualify future fuels by using bench-scale and component testing are being sought. Fuel blends with increasing JP5-type aromatic concentration were seen to produce less volume swell than an equivalent aromatic concentration in the reference fuel. Futhermore, blends with naphthenes, decalin, tetralin, and naphthalenes do not deviate significantly from the correlation line of aromatic blends, Similar results are found with tensile strenth and elongation. Other elastomers, sealants, and adhesives are also being tested.

  5. A conceptual study of the rotor systems research aircraft

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The analytical comparison of the two candidate Rotor Systems Research Aircraft (RSRA) configurations selected by the Government at the completion of Part 1 of the RSRA Conceptual Predesign Study is presented. The purpose of the comparison was to determine the relative suitability of both vehicles for the RSRA missions described in the Government Statement of Work, and to assess their versatility in the testing of new rotor concepts. The analytical comparison was performed primarily with regard to performance and stability and control. A weights, center-of-gravity, and inertia computation was performed for each iteration in the analysis process. The dynamics investigation was not concerned so much with a comparison of the two vehicles, but explored the dynamic problems attending operation of any RSRA operating with large rotor RPM and diameter ranges over large forward speed ranges. Several means of isolating in- and out-of-plane rotor vibrations were analyzed. An optimum isolation scheme was selected.

  6. Algorithm of Unmanned Aircraft Systems Displacement in Airspace

    NASA Astrophysics Data System (ADS)

    Gugała, Tomasz

    Despite the fact Unmanned Aerial Vehicles have been used for more than 70 years and their uncommon development has taken place in the first decade of the 21st Century, there is still no elaboration of "Uniform Concept of the Unmanned Aircraft Systems Displacement in Airspace". The indispensable condition of the above mentioned concept has to be flight safety of all airspace users. To achieve this goal, it is necessary to work out the adequate procedures and regulations in the scope of airspace usage taking into consideration this upto- date means of air transport. Therefore, elaboration of the algorithm by the author, can be a reason of achievement for the above mentioned object in the near future. Under such circumstances, the author has taken the trial to perform this challenging task.

  7. Direct Electricity from Heat: A Solution to Assist Aircraft Power Demands

    NASA Technical Reports Server (NTRS)

    Goldsby, Jon C.

    2010-01-01

    A thermionic device produces an electrical current with the application of a thermal gradient whereby the temperature at one electrode provides enough thermal energy to eject electrons. The system is totally predicated on the thermal gradient and the work function of the electrode collector relative to the emitter electrode. Combined with a standard thermoelectric device high efficiencies may result, capable of providing electrical energy from the waste heat of gas turbine engines.

  8. Research for electric energy systems

    NASA Astrophysics Data System (ADS)

    Anderson, W. E.

    1991-06-01

    The technical progress in four investigations which make up the project 'Support of Research Projects for Electrical Energy Systems,' funded by the U.S. Department of Energy and performed by the Electricity Division of the National Institute of Standards and Technology (NIST) is discussed. These investigations include measurements of magnetic fields in support of epidemiological and in vitro studies of biological field effects; development of a technique to measure trace amounts of S2F10 in the presence of SF6 and the development of an improved stochastic analyzer for pulsating phenomena; optical and electrical measurements of negative streamers preceding electric breakdown in liquid dielectrics; and the development of a reference resistive divider for high voltage impulse measurements.

  9. Effect of power system technology and mission requirements on high altitude long endurance aircraft

    NASA Technical Reports Server (NTRS)

    Colozza, Anthony J.

    1994-01-01

    An analysis was performed to determine how various power system components and mission requirements affect the sizing of a solar powered long endurance aircraft. The aircraft power system consists of photovoltaic cells and a regenerative fuel cell. Various characteristics of these components, such as PV cell type, PV cell mass, PV cell efficiency, fuel cell efficiency, and fuel cell specific mass, were varied to determine what effect they had on the aircraft sizing for a given mission. Mission parameters, such as time of year, flight altitude, flight latitude, and payload mass and power, were also altered to determine how mission constraints affect the aircraft sizing. An aircraft analysis method which determines the aircraft configuration, aspect ratio, wing area, and total mass, for maximum endurance or minimum required power based on the stated power system and mission parameters is presented. The results indicate that, for the power system, the greatest benefit can be gained by increasing the fuel cell specific energy. Mission requirements also substantially affect the aircraft size. By limiting the time of year the aircraft is required to fly at high northern or southern latitudes, a significant reduction in aircraft size or increase in payload capacity can be achieved.

  10. Fail-safe system for activity cooled supersonic and hypersonic aircraft. [using liquid hydrogen fuel

    NASA Technical Reports Server (NTRS)

    Jones, R. A.; Braswell, D. O.; Richie, C. B.

    1975-01-01

    A fail-safe-system concept was studied as an alternative to a redundant active cooling system for supersonic and hypersonic aircraft which use the heat sink of liquid-hydrogen fuel for cooling the aircraft structure. This concept consists of an abort maneuver by the aircraft and a passive thermal protection system (TPS) for the aircraft skin. The abort manuever provides a low-heat-load descent from normal cruise speed to a lower speed at which cooling is unnecessary, and the passive TPS allows the aircraft skin to absorb the abort heat load without exceeding critical skin temperature. On the basis of results obtained, it appears that this fail-safe-system concept warrants further consideration, inasmuch as a fail-safe system could possibly replace a redundant active cooling system with no increase in weight and would offer other potential advantages.

  11. European activities in civil applications of drones: an overview of remotely piloted aircraft systems (RPAS)

    NASA Astrophysics Data System (ADS)

    Creutzburg, Reiner

    2015-05-01

    The aim of this paper is to give an overview of recent research, development and civil application of remotely piloted aircraft systems (RPAS) in Europe. It describes a European strategy for the development of civil applications of Remotely Piloted Aircraft Systems (RPAS) and reflects most of the contents of the European staff working document SWD(2012) 259 final.

  12. Portable device to assess dynamic accuracy of global positioning systems (GPS) receivers used in agricultural aircraft

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A device was designed to test the dynamic accuracy of Global Positioning System (GPS) receivers used in aerial vehicles. The system works by directing a sun-reflected light beam from the ground to the aircraft using mirrors. A photodetector is placed pointing downward from the aircraft and circuitry...

  13. The Design and Implementation of Aircraft Maintenance On-site Control System

    NASA Astrophysics Data System (ADS)

    Zhou, Guilin; Zhang, Huawei

    Based on the desire of aircraft maintenance, combined with the situation in work, this paper present the design and implementation of aircraft maintenance system based dot Net. For a partial page refresh object, AJAX is used through the system. New technology is used in a creative way and will promote innovation and transformation of the business.

  14. Future Integrated Systems Concept for Preventing Aircraft Loss-of-Control Accidents

    NASA Technical Reports Server (NTRS)

    Belcastro, Christine M.; Jacobson, Steven r.

    2010-01-01

    Loss of control remains one of the largest contributors to aircraft fatal accidents worldwide. Aircraft loss-of-control accidents are highly complex in that they can result from numerous causal and contributing factors acting alone or (more often) in combination. Hence, there is no single intervention strategy to prevent these accidents. This paper presents future system concepts and research directions for preventing aircraft loss-of-control accidents.

  15. Electrical power system WP-04

    NASA Technical Reports Server (NTRS)

    Nored, Donald L.

    1990-01-01

    Viewgraphs on Space Station Freedom Electrical Power System (EPS) WP-40 are presented. Topics covered include: key EPS technical requirements; photovoltaic power module systems; solar array assembly; blanket containment box and box positioning subassemblies; solar cell; bypass diode assembly; Kapton with atomic oxygen resistant coating; sequential shunt unit; gimbal assembly; energy storage subsystem; thermal control subsystem; direct current switching unit; integrated equipment assembly; PV cargo element; PMAD system; and PMC and AC architecture.

  16. Key Performance Parameter Driven Technology Goals for Electric Machines and Power Systems

    NASA Technical Reports Server (NTRS)

    Bowman, Cheryl; Jansen, Ralph; Brown, Gerald; Duffy, Kirsten; Trudell, Jeffrey

    2015-01-01

    Transitioning aviation to low carbon propulsion is one of the crucial strategic research thrust and is a driver in the search for alternative propulsion system for advanced aircraft configurations. This work requires multidisciplinary skills coming from multiple entities. The feasibility of scaling up various electric drive system technologies to meet the requirements of a large commercial transport is discussed in terms of key parameters. Functional requirements are identified that impact the power system design. A breakeven analysis is presented to find the minimum allowable electric drive specific power and efficiency that can preserve the range, initial weight, operating empty weight, and payload weight of the base aircraft.

  17. Electric propulsion system technology

    NASA Astrophysics Data System (ADS)

    Brophy, John R.; Garner, Charles E.; Goodfellow, Keith D.; Pivirotto, Thomas J.; Polk, James E.

    1992-11-01

    The work performed in fiscal year (FY) 1991 under the Propulsion Technology Program RTOP (Research and Technology Objectives and Plans) No. (55) 506-42-31 for Low-Thrust Primary and Auxiliary Propulsion technology development is described. The objectives of this work fall under two broad categories. The first of these deals with the development of ion engines for primary propulsion in support of solar system exploration. The second with the advancement of steady-state magnetoplasmadynamic (MPD) thruster technology at 100 kW to multimegawatt input power levels. The major technology issues for ion propulsion are demonstration of adequate engine life at the 5 to 10 kW power level and scaling ion engines to power levels of tens to hundreds of kilowatts. Tests of a new technique in which the decelerator grid of a three-grid ion accelerator system is biased negative of neutralizer common potential in order to collect facility induced charge-exchange ions are described. These tests indicate that this SAND (Screen, Accelerator, Negative Decelerator) configuration may enable long duration ion engine endurance tests to be performed at vacuum chamber pressures an order of magnitude higher than previously possible. The corresponding reduction in pumping speed requirements enables endurance tests of 10 kW class ion engines to be performed within the resources of existing technology programs. The results of a successful 5,000-hr endurance of a xenon hollow cathode operating at an emission current of 25 A are described, as well as the initial tests of hollow cathodes operating on a mixture of argon and 3 percent nitrogen. Work performed on the development of carbon/carbon grids, a multi-orifice hollow cathode, and discharge chamber erosion reduction through the addition of nitrogen are also described. Critical applied-field MPD thruster technical issues remain to be resolved, including demonstration of reliable steady-state operation at input powers of hundreds to thousands of

  18. Electric propulsion system technology

    NASA Technical Reports Server (NTRS)

    Brophy, John R.; Garner, Charles E.; Goodfellow, Keith D.; Pivirotto, Thomas J.; Polk, James E.

    1992-01-01

    The work performed in fiscal year (FY) 1991 under the Propulsion Technology Program RTOP (Research and Technology Objectives and Plans) No. (55) 506-42-31 for Low-Thrust Primary and Auxiliary Propulsion technology development is described. The objectives of this work fall under two broad categories. The first of these deals with the development of ion engines for primary propulsion in support of solar system exploration. The second with the advancement of steady-state magnetoplasmadynamic (MPD) thruster technology at 100 kW to multimegawatt input power levels. The major technology issues for ion propulsion are demonstration of adequate engine life at the 5 to 10 kW power level and scaling ion engines to power levels of tens to hundreds of kilowatts. Tests of a new technique in which the decelerator grid of a three-grid ion accelerator system is biased negative of neutralizer common potential in order to collect facility induced charge-exchange ions are described. These tests indicate that this SAND (Screen, Accelerator, Negative Decelerator) configuration may enable long duration ion engine endurance tests to be performed at vacuum chamber pressures an order of magnitude higher than previously possible. The corresponding reduction in pumping speed requirements enables endurance tests of 10 kW class ion engines to be performed within the resources of existing technology programs. The results of a successful 5,000-hr endurance of a xenon hollow cathode operating at an emission current of 25 A are described, as well as the initial tests of hollow cathodes operating on a mixture of argon and 3 percent nitrogen. Work performed on the development of carbon/carbon grids, a multi-orifice hollow cathode, and discharge chamber erosion reduction through the addition of nitrogen are also described. Critical applied-field MPD thruster technical issues remain to be resolved, including demonstration of reliable steady-state operation at input powers of hundreds to thousands of

  19. Acceleration display system for aircraft zero-gravity research

    NASA Technical Reports Server (NTRS)

    Millis, Marc G.

    1987-01-01

    The features, design, calibration, and testing of Lewis Research Center's acceleration display system for aircraft zero-gravity research are described. Specific circuit schematics and system specifications are included as well as representative data traces from flown trajectories. Other observations learned from developing and using this system are mentioned where appropriate. The system, now a permanent part of the Lewis Learjet zero-gravity program, provides legible, concise, and necessary guidance information enabling pilots to routinely fly accurate zero-gravity trajectories. Regular use of this system resulted in improvements of the Learjet zero-gravity flight techniques, including a technique to minimize later accelerations. Lewis Gates Learjet trajectory data show that accelerations can be reliably sustained within 0.01 g for 5 consecutive seconds, within 0.02 g for 7 consecutive seconds, and within 0.04 g for up to 20 second. Lewis followed the past practices of acceleration measurement, yet focussed on the acceleration displays. Refinements based on flight experience included evolving the ranges, resolutions, and frequency responses to fit the pilot and the Learjet responses.

  20. Understanding electrostatic charge behaviour in aircraft fuel systems

    NASA Astrophysics Data System (ADS)

    Ogilvy, Jill A.; Hooker, Phil; Bennett, Darrell

    2015-10-01

    This paper presents work on the simulation of electrostatic charge build-up and decay in aircraft fuel systems. A model (EC-Flow) has been developed by BAE Systems under contract to Airbus, to allow the user to assess the effects of changes in design or in refuel conditions. Some of the principles behind the model are outlined. The model allows for a range of system components, including metallic and non-metallic pipes, valves, filters, junctions, bends and orifices. A purpose-built experimental rig was built at the Health and Safety Laboratory in Buxton, UK, to provide comparison data. The rig comprises a fuel delivery system, a test section where different components may be introduced into the system, and a Faraday Pail for measuring generated charge. Diagnostics include wall currents, charge densities and pressure losses. This paper shows sample results from the fitting of model predictions to measurement data and shows how analysis may be used to explain some of the observed trends.

  1. Electricity Market Complex Adaptive System

    SciTech Connect

    2004-10-14

    EMCAS is a model developed for the simulation and analysis of electricity markets. As power markets are relatively new and still continue to evolve, there is a growing need for advanced modeling approaches that simulate the behavior of electricity markets over time and how market participants may act and react to the changing economic, financial, and regulatory environments in which they operate. A new and rather promising approach applied in the EMCAS software is to model the electricity market as a complex adaptive system using an agent-based modeling and simulation scheme. With its unique combination of various novel approaches, the Agent Based Modeling System (ABMS) provides the ability to capture and investigate the complex interactions between the physical infrastructures (generation, transmission, and distribution) and the economic behavior of market participants that are a trademark of the newly emerging markets.

  2. Electricity Market Complex Adaptive System

    2004-10-14

    EMCAS is a model developed for the simulation and analysis of electricity markets. As power markets are relatively new and still continue to evolve, there is a growing need for advanced modeling approaches that simulate the behavior of electricity markets over time and how market participants may act and react to the changing economic, financial, and regulatory environments in which they operate. A new and rather promising approach applied in the EMCAS software is tomore » model the electricity market as a complex adaptive system using an agent-based modeling and simulation scheme. With its unique combination of various novel approaches, the Agent Based Modeling System (ABMS) provides the ability to capture and investigate the complex interactions between the physical infrastructures (generation, transmission, and distribution) and the economic behavior of market participants that are a trademark of the newly emerging markets.« less

  3. 44. LOCK, ELECTRICAL SYSTEM, HAULAGE ENGINES, ELECTRICAL DETAILS AND LOCATION. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    44. LOCK, ELECTRICAL SYSTEM, HAULAGE ENGINES, ELECTRICAL DETAILS AND LOCATION. February 1938 - Mississippi River 9-Foot Channel Project, Lock & Dam No. 17, Upper Mississippi River, New Boston, Mercer County, IL

  4. Tropical Cyclone Precipitation Types and Electrical Field Information Observed by High Altitude Aircraft Instrumentation

    NASA Technical Reports Server (NTRS)

    Hood, Robbie E.; Blakeslee, Richard; Cecil, Daniel; LaFontaine, Frank J.; Heymsfield, Gerald; Marks, Frank

    2004-01-01

    During the 1998 and 200 1 hurricane seasons of the Atlantic Ocean Basin, the Advanced Microwave Precipitation Radiometer (AMPR), the ER-2 Doppler (EDOP) radar, and the Lightning Instrument Package (LIP) were flown aboard the National Aeronautics and Space Administration (NASA) ER-2 high altitude aircraft as part of the Third Convection And Moisture Experiment (CAMEX-3) and the Fourth Convection And Moisture Experiment (CAMEX-4). Several hurricanes and tropical storms were sampled during these experiments. A rainfall screening technique has been developed using AMPR passive microwave observations of these tropical cyclones (TC) collected at frequencies of 10.7, 19.35,37.1, and 85.5 GHz and verified using vertical profiles of EDOP reflectivity and lower altitude horizontal reflectivity scam collected by the National Oceanic and Atmospheric Administration (NOM) P-3 radar. Matching the rainfall classification results with coincident electrical field information collected by the LIP readily identifl convective rain regions within the TC precipitation fields. Strengths and weaknesses of the rainfall classification procedure will be discussed as well as its potential as a real-time analysis tool for monitoring vertical updrafl strength and convective intensity from a remotely operated or uninhabited aerial vehicle.

  5. Development and system identification of a light unmanned aircraft for flying qualities research

    SciTech Connect

    Peters, M.E.; Andrisani, D. II

    1994-12-31

    This paper describes the design, construction, flight testing and system identification of a light weight remotely piloted aircraft and its use in studying flying qualities in the longitudinal axis. The short period approximation to the longitudinal dynamics of the aircraft was used. Parameters in this model were determined a priori using various empirical estimators. These parameters were then estimated from flight data using a maximum likelihood parameter identification method. A comparison of the parameter values revealed that the stability derivatives obtained from the empirical estimators were reasonably close to the flight test results. However, the control derivatives determined by the empirical estimators were too large by a factor of two. The aircraft was also flown to determine how the longitudinal flying qualities of light weight remotely piloted aircraft compared to full size manned aircraft. It was shown that light weight remotely piloted aircraft require much faster short period dynamics to achieve level I flying qualities in an up-and-away flight task.

  6. Application of surface electrical discharges to the study of lightning strikes on aircraft

    NASA Technical Reports Server (NTRS)

    Boulay, J. L.; Larigaldie, S.

    1991-01-01

    Considered here is the characterization of surface discharges which provide a facility complementary to that of artificially triggered lightning. General characteristics of a simplified surface discharge, including current waveforms and the constitution of a surface discharge are outlined, and the application of this approach to the study of aircraft lightning strikes is considered. Representations of leader-streamer and return-stroke phases are discussed, and the application to the two-dimensional discharge phase is covered. It is noted that the fact that the initiation times of surface discharges could be controlled, and the path followed by the discharge channels could be predetermined, indicates that it is possible to produce a highly dedicated high performance instrumentation system.

  7. Design of a digital ride quality augmentation system for commuter aircraft

    NASA Technical Reports Server (NTRS)

    Hammond, T. A.; Amin, S. P.; Paduano, J. D.; Downing, D. R.

    1984-01-01

    Commuter aircraft typically have low wing loadings, and fly at low altitudes, and so they are susceptible to undesirable accelerations caused by random atmospheric turbulence. Larger commercial aircraft typically have higher wing loadings and fly at altitudes where the turbulence level is lower, and so they provide smoother rides. This project was initiated based on the goal of making the ride of the commuter aircraft as smooth as the ride experienced on the major commercial airliners. The objectives of this project were to design a digital, longitudinal mode ride quality augmentation system (RQAS) for a commuter aircraft, and to investigate the effect of selected parameters on those designs.

  8. Human Performance Considerations for Remotely Piloted Aircraft Systems (RPAS)

    NASA Technical Reports Server (NTRS)

    Shively, R. Jay; Hobbs, Alan; Lyall, Beth; Rorie, Conrad

    2015-01-01

    Successful integration of Remotely Piloted Aircraft Systems (RPAS) into civil airspace will not only require solutions to technical challenges, but will also require that the design and operation of RPAS take into account human limitations and capabilities. Human factors can affect overall system performance whenever the system relies on people to interact with another element of the system. Four types of broad interactions can be described. These are (1) interactions between people and hardware, such as controls and displays; (2) human use of procedures and documentation; (3) impact of the task environment, including lighting, noise and monotony; and lastly, (4) interactions between operational personnel, including communication and coordination. In addition to the human factors that have been identified for conventional aviation, RPAS operations introduce a set of unique human challenges. The purpose of document is to raise human factors issues for consideration by workgroups of the ICAO RPAS panel as they work to develop guidance material and additions to ICAO annexes. It is anticipated that the content of this document will be revised and updated as the work of the panel progresses.

  9. Rotor systems research aircraft predesign study. Volume 2: Conceptual study report

    NASA Technical Reports Server (NTRS)

    Schmidt, S. A.; Linden, A. W.

    1972-01-01

    The overall feasibility of the technical requirements and concepts for a rotor system research aircraft (RSRA) was determined. The designs of two aircraft were then compared against the RSRA requirements. One of these is an all new aircraft specifically designed as an RSRA vehicle. A new main rotor, transmission, wings, and fuselage are included in this design. The second aircraft uses an existing Sikorsky S-61 main rotor, an S-61 roller gearbox, and a highly modified Sikorsky S-67 airframe. The wing for this aircraft is a new design. Both aircraft employ a fan-in-fin anti-torque/yaw control system, T58-GE-16 engines for rotor power, and TF34-GE-2 turbofans for auxiliary thrust. Each aircraft meets the basic requirements and goals of the program. The all new aircraft has inflight variable main rotor shaft tilt, a side-by-side cockpit seating arrangement, and is slightly faster in the compound mode. It is also somewhat lighter since it uses new dynamic components specifically designed for the RSRA. Preliminary development plans, including schedules and costs, were prepared for both of these aircraft.

  10. Effects of cable geometry and aircraft attitude on the accuracy of a magnetic leader cable system for aircraft guidance during rollout and turnoff

    NASA Technical Reports Server (NTRS)

    Bundick, W. T.

    1982-01-01

    A theoretical analysis of a single wire magnetic leader cable system for aircraft rollout and turnoff guidance was performed to determine the errors produced by the leader cable installation geometry and aircraft attitude. It was found that errors in the measurement of lateral displacement from the cable are smaller than errors in the measurement of aircraft heading and that both errors are smallest at or near the cable.

  11. Two and three dimensional systems for computer aided geometric design of aircraft surface and components

    NASA Astrophysics Data System (ADS)

    Aryeh, F.

    1982-01-01

    Three interactive software systems dealing with the computerized definition, storage and handling of aircraft geometric shapes and entities in a multidisciplinary design environment are presented. The systems are operated in an interactive fashion via use of low cost graphic display terminals driven by a remote computer in a time sharing mode. GEODEF is a system for interactive definition of complex aircraft surfaces, GEOBASE is a system for interrogation and manipulation of a computerized aircraft geometry data base, and DOG is a 3-D detailed structural and mechanical part definition system.

  12. Data acquisition/reduction system for flight testing general aviation aircraft

    NASA Technical Reports Server (NTRS)

    Rummer, D. I.; Mosser, M. A.; Renz, R. R. L.

    1982-01-01

    The development of a data acquisition/reduction system for use in the flight testing of general aviation aircraft is described. Design objectives for the system are adequate accuracy, ease of installation and removal from aircraft, simplicity of operation, and low cost. A 16-channel working system has been constructed, and tested in the collection of flight test data from a Cessna 172 aircraft, which uses as the basis of its design an AIM65 microcomputer. Data is reduced with a MINC minicomputer system. Attention is given to the onboard installation of computer, battery and transducer modules incorporated by the system.

  13. Development of a 21st Century Small Aircraft Transportation System

    NASA Technical Reports Server (NTRS)

    Bowen, Brent D.; Holmes, Bruce J.; Hansen, Frederick

    2000-01-01

    The National Aeronautics and Space Administration (NASA), U.S. Department of Transportation, Federal Aviation Administration, industry stakeholders, and academia, have joined forces to pursue the NASA National General Aviation Roadmap leading to a Small Aircraft Transportation System (SATS). This strategic undertaking has a 25-year goal to bring the next-generation technologies and improve travel between remote communities and transportation centers in urban areas by utilizing the nation's 5,400 public use general aviation airports. To facilitate this initiative, a comprehensive upgrade of public infrastructure must be planned, coordinated, and implemented within the framework of the national air transportation system. The Nebraska NASA EPSCoR Program has proposed to deliver research support in key public infrastructure areas in coordination with the General Aviation Program Office at the NASA Langley Research Center. Ultimately, SATS may permit tripling aviation system throughput capacity by tapping the underutilized general aviation facilities to achieve the national goal of doorstep-to-destination travel at four times the speed of highways for the nation's suburban, rural, and remote communities.

  14. New Mobile Lidar Systems Aboard Ultra-Light Aircrafts

    NASA Astrophysics Data System (ADS)

    Chazette, Patrick; Shang, Xiaoxia; Totems, Julien; Marnas, Fabien; Sanak, Joseph

    2013-04-01

    Two lidar systems embedded on ultra light aircraft (ULA) flew over the Rhone valley, south-east of France, to characterize the vertical extend of pollution aerosols in this area influenced by large industrial sites. The main industrial source is the Etang de Berre (43°28' N, 5°01' E), close to Marseille city. The emissions are mainly due to metallurgy and petrochemical factories. Traffic related to Marseille's area contribute to pollution with its ~1500000 inhabitants. Note that the maritime traffic close to Marseille may play an important role due to its position as the leading French harbor . For the previous scientific purpose and for the first time on ULA, we flew a mini-N2 Raman lidar system to help the assessment of the aerosol optical properties. Another Ultra-Violet Rayleigh-Mie lidar has been integrated aboard a second ULA. The lidars are compact and eye safe instruments. They operate at the wavelength of 355 nm with a sampling along the line-of-sight of 0.75 m. Different flights plans were tested to use the two lidars in synergy. We will present the different approaches and discuss both their advantages and limitations. Acknowledgements: the lidar systems have been developed by CEA. They have been deployed with the support of FERRING France. We acknowledge the ULA pilots Franck Toussaint, François Bernard and José Coutet, and the Air Creation ULA Company for logistical help during the ULA campaign.

  15. Research for electric energy systems

    NASA Astrophysics Data System (ADS)

    Anderson, W. E.

    1993-10-01

    This report documents the technical progress in the two investigations which make up the project 'Support of Research Projects for Electrical Energy Systems,' Department of Energy Task Order Number 137, funded by the US Department of Energy and performed by the Electricity Division of the National Institute of Standards and Technology (NIST). The first investigation is concerned with the measurement of magnetic fields in support of epidemiogical and in vitro studies of biological field effects. During 1992, the derivation of equations which predict differences between the average magnetic flux density using circular coil probes and the flux density at the center of the probe, assuming a dipole magnetic field, were completed. The information gained using these equations allows the determination of measurement uncertainty due to probe size when magnetic fields from many electrical appliances are characterized. Consultations with various state and federal organizations and the development of standards related to electric and magnetic field measurements continued. The second investigation is concerned with two different activities related to compressed-gas insulated high voltage systems: the measurement of dissociative electron attachment cross sections and negative ion production in S2F10, S2OF10, and S2O2F10, and Monte-Carlo simulations of ac-generated partial-discharge pulses that can occur in SF6-insulated power systems and can be sources of gas decomposition.

  16. Advanced piloted aircraft flight control system design methodology. Volume 2: The FCX flight control design expert system

    NASA Technical Reports Server (NTRS)

    Myers, Thomas T.; Mcruer, Duane T.

    1988-01-01

    The development of a comprehensive and electric methodology for conceptual and preliminary design of flight control systems is presented and illustrated. The methodology is focused on the design states starting with the layout of system requirements and ending when some viable competing system architectures (feedback control structures) are defined. The approach is centered on the human pilot and the aircraft as both the sources of, and the keys to the solution of, many flight control problems. The methodology relies heavily on computational procedures which are highly interactive with the design engineer. To maximize effectiveness, these techniques, as selected and modified to be used together in the methodology, form a cadre of computational tools specifically tailored for integrated flight control system preliminary design purposes. The FCX expert system as presently developed is only a limited prototype capable of supporting basic lateral-directional FCS design activities related to the design example used. FCX presently supports design of only one FCS architecture (yaw damper plus roll damper) and the rules are largely focused on Class IV (highly maneuverable) aircraft. Despite this limited scope, the major elements which appear necessary for application of knowledge-based software concepts to flight control design were assembled and thus FCX represents a prototype which can be tested, critiqued and evolved in an ongoing process of development.

  17. The F-12 series aircraft approach to design for control system reliability

    NASA Technical Reports Server (NTRS)

    Schenk, F. L.; Mcmaster, J. R.

    1976-01-01

    The F-12 series aircraft control system design philosophy is reviewed as it pertains to functional reliability. The basic control system, i.e., cables, mixer, feel system, trim devices, and hydraulic systems are described and discussed. In addition, the implementation of the redundant stability augmentation system in the F-12 aircraft is described. Finally, the functional reliability record that has been achieved is presented.

  18. Aircraft System Analysis of Technology Benefits to Civil Transport Rotorcraft

    NASA Technical Reports Server (NTRS)

    Wilkerson, Joseph B.; Smith, Roger L.

    2008-01-01

    An aircraft systems analysis was conducted to evaluate the net benefits of advanced technologies on two conceptual civil transport rotorcraft, to quantify the potential of future civil rotorcraft to become operationally viable and economically competitive, with the ultimate goal of alleviating congestion in our airways, runways and terminals. These questions are three of many that must be resolved for the successful introduction of civil transport rotorcraft: 1) Can civil transport rotorcraft actually relieve current airport congestion and improve overall air traffic and passenger throughput at busy hub airports? What is that operational scenario? 2) Can advanced technology make future civil rotorcraft economically competitive in scheduled passenger transport? What are those enabling technologies? 3) What level of investment is necessary to mature the key enabling technologies? This study addresses the first two questions, and several others, by applying a systems analysis approach to a broad spectrum of potential advanced technologies at a conceptual level of design. The method was to identify those advanced technologies that showed the most promise and to quantify their benefits to the design, development, production, and operation of future civil rotorcraft. Adjustments are made to sizing data by subject matter experts to reflect the introduction of new technologies that offer improved performance, reduced weight, reduced maintenance, or reduced cost. This study used projected benefits from new, advanced technologies, generally based on research results, analysis, or small-scale test data. The technologies are identified, categorized and quantified in the report. The net benefit of selected advanced technologies is quantified for two civil transport rotorcraft concepts, a Single Main Rotor Compound (SMRC) helicopter designed for 250 ktas cruise airspeed and a Civil Tilt Rotor (CTR) designed for 350 ktas cruise airspeed. A baseline design of each concept was

  19. Shunt regulation electric power system

    NASA Technical Reports Server (NTRS)

    Wright, W. H.; Bless, J. J. (Inventor)

    1971-01-01

    A regulated electric power system having load and return bus lines is described. A plurality of solar cells interconnected in a power supplying relationship and having a power shunt tap point electrically spaced from the bus lines is provided. A power dissipator is connected to the shunt tap point and provides for a controllable dissipation of excess energy supplied by the solar cells. A dissipation driver is coupled to the power dissipator and controls its conductance and dissipation and is also connected to the solar cells in a power taping relationship to derive operating power therefrom. An error signal generator is coupled to the load bus and to a reference signal generator to provide an error output signal which is representative of the difference between the electric parameters existing at the load bus and the reference signal generator. An error amplifier is coupled to the error signal generator and the dissipation driver to provide the driver with controlling signals.

  20. Aircraft as adaptive nonlinear system which must be in the adaptational maximum zone for safety

    SciTech Connect

    Ignative, M.; Simatos, N.; Sivasundaram, S.

    1994-12-31

    Safety is a main problem in aircraft. We are considering this problem from the point of view related to existence of the adaptational maximum in complex developing systems. Safety space of aircraft parameters are determined. This space is transformed to different regimes of flight, when one engine malfunctions etc., are considered. Also it is shown that maximum safety is in adaptational maximum zone.

  1. STOL terminal area operating systems (aircraft and onboard avionics, ATC, navigation aids)

    NASA Technical Reports Server (NTRS)

    Burrous, C.; Erzberger, H.; Johnson, N.; Neuman, F.

    1974-01-01

    Operational procedures and systems onboard the STOL aircraft which are required to enable the aircraft to perform acceptably in restricted airspace in all types of atmospheric conditions and weather are discussed. Results of simulation and flight investigations to establish operational criteria are presented.

  2. 78 FR 20168 - Twenty Fourth Meeting: RTCA Special Committee 203, Unmanned Aircraft Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-03

    ... Federal Aviation Administration Twenty Fourth Meeting: RTCA Special Committee 203, Unmanned Aircraft...: Meeting Notice of RTCA Special Committee 203, Unmanned Aircraft Systems. SUMMARY: The FAA is issuing this notice to advise the public of the twenty third meeting of RTCA Special Committee 203, Unmanned...

  3. 77 FR 50207 - Twenty-Second Meeting: RTCA Special Committee 203, Unmanned Aircraft Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-20

    ... Federal Aviation Administration Twenty-Second Meeting: RTCA Special Committee 203, Unmanned Aircraft...: Meeting notice of RTCA Special Committee 203, Unmanned Aircraft Systems. SUMMARY: The FAA is issuing this notice to advise the public of the twenty-second meeting of RTCA Special Committee 203, Unmanned...

  4. 77 FR 25781 - Twenty-First Meeting: RTCA Special Committee 203, Unmanned Aircraft Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-01

    ... Federal Aviation Administration Twenty-First Meeting: RTCA Special Committee 203, Unmanned Aircraft...: Meeting Notice of RTCA Special Committee 203, Unmanned Aircraft Systems. SUMMARY: The FAA is issuing this notice to advise the public of the twenty-first meeting of RTCA Special Committee 203, Unmanned...

  5. 78 FR 6400 - Twenty Third Meeting: RTCA Special Committee 203, Unmanned Aircraft Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-30

    ... Federal Aviation Administration Twenty Third Meeting: RTCA Special Committee 203, Unmanned Aircraft...: Meeting Notice of RTCA Special Committee 203, Unmanned Aircraft Systems. SUMMARY: The FAA is issuing this notice to advise the public of the twenty third meeting of RTCA Special Committee 203, Unmanned...

  6. Energy efficient engine flight propulsion system: Aircraft/engine integration evaluation

    NASA Technical Reports Server (NTRS)

    Patt, R. F.

    1980-01-01

    Results of aircraft/engine integration studies conducted on an advanced flight propulsion system are reported. Economic evaluations of the preliminary design are included and indicate that program goals will be met. Installed sfc, DOC, noise, and emissions were evaluated. Aircraft installation considerations and growth were reviewed.

  7. Detailed design of a Ride Quality Augmentation System for commuter aircraft

    NASA Technical Reports Server (NTRS)

    Suikat, Reiner; Donaldson, Kent E.; Downing, David R.

    1989-01-01

    The design of a Ride Quality Augmentation System (RQAS) for commuter aircraft is documented. The RQAS is designed for a Cessna 402B, an 8 passenger prop twin representative to this class of aircraft. The purpose of the RQAS is the reduction of vertical and lateral accelerations of the aircraft due to atmospheric turbulence by the application of active control. The detailed design of the hardware (the aircraft modifications, the Ride Quality Instrumentation System (RQIS), and the required computer software) is examined. The aircraft modifications, consisting of the dedicated control surfaces and the hydraulic actuation system, were designed at Cessna Aircraft by Kansas University-Flight Research Laboratory. The instrumentation system, which consist of the sensor package, the flight computer, a Data Acquisition System, and the pilot and test engineer control panels, was designed by NASA-Langley. The overall system design and the design of the software, both for flight control algorithms and ground system checkout are detailed. The system performance is predicted from linear simulation results and from power spectral densities of the aircraft response to a Dryden gust. The results indicate that both accelerations are possible.

  8. Littoral environmental reconnaissance using tactical imagery from unmanned aircraft systems

    NASA Astrophysics Data System (ADS)

    Holland, K. Todd; Lalejini, David M.; Spansel, Steven D.; Holman, Robert A.

    2010-04-01

    The dynamic nature of littoral regions requires a reconnaissance approach that can rapidly quantify environmental conditions. Inadequate estimation of these conditions can have substantial impacts on the performance of Naval systems. Given that expeditionary warfare operations can occur over timescales on the order of hours, exploitation of video imagery from tactical vehicles such as Unmanned Aircraft Systems (UAS) has proved to be a reliable and adaptive solution. Tactical littoral products that can be created by exploiting UAS imagery include estimates of surf conditions, dominant wave period, wave direction, nearshore currents, and bathymetry. These vehicles can fly for durations of 1-2 hours at altitudes of less than 1000 m (beneath typical cloud cover) to obtain imagery at pixel resolutions better than 1 m. The main advantage of using imaging sensors carried by these vehicles is that the data is available in the region of operational interest where other data collection approaches would be difficult or impossible to employ. The through-the-sensor exploitation technique we have developed operates in two phases. The first step is to align individual image frames to a common reference and then georegister the alignment into a mapped image sequence. The second phase involves signal processing of pixel intensity time series (virtual sensors) to determine spatial relationships over time. Geophysical relationships, such as linear wave dispersion, can then be applied to these processed data to invert for environmental parameters such as bathymetry.

  9. Unmanned Aircraft System Control and ATC Communications Bandwidth Requirements

    NASA Technical Reports Server (NTRS)

    Henriksen, Steve

    2008-01-01

    There are significant activities taking place to establish the procedures and requirements for safe and routine operation of unmanned aircraft systems (UAS) in the National Airspace System (NAS). Among the barriers to overcome in achieving this goal is the lack of sufficient frequency spectrum necessary for the UAS control and air traffic control (ATC) communications links. This shortcoming is compounded by the fact that the UAS control communications links will likely be required to operate in protected frequency spectrum, just as ATC communications links are, because they relate to "safety and regularity of flight." To support future International Telecommunications Union (ITU) World Radio Conference (WRC) agenda items concerning new frequency allocations for UAS communications links, and to augment the Future Communications Study (FCS) Technology Evaluation Group efforts, NASA Glenn Research Center has sponsored a task to estimate the UAS control and ATC communications bandwidth requirements for safe, reliable, and routine operation of UAS in the NAS. This report describes the process and results of that task. The study focused on long-term bandwidth requirements for UAS approximately through 2030.

  10. Flight control systems research. [optimization of F-8 aircraft control system

    NASA Technical Reports Server (NTRS)

    Whitaker, H. P.; Baram, Y.; Cheng, Y.

    1973-01-01

    Theoretical development is reported for the parameter optimization design technique needed for digital flight control system design. The results of an example case study applying the optimization technique for continuous systems to an F-8 aircraft feedback control system are presented. The concept of evolving the simplest system configuration that is capable of meeting a specified set of performance requirements is illustrated in this work.

  11. Air traffic control resource management strategies and the small aircraft transportation system: A system dynamics perspective

    NASA Astrophysics Data System (ADS)

    Galvin, James J., Jr.

    The National Aeronautics and Space Administration (NASA) is leading a research effort to develop a Small Aircraft Transportation System (SATS) that will expand air transportation capabilities to hundreds of underutilized airports in the United States. Most of the research effort addresses the technological development of the small aircraft as well as the systems to manage airspace usage and surface activities at airports. The Federal Aviation Administration (FAA) will also play a major role in the successful implementation of SATS, however, the administration is reluctant to embrace the unproven concept. The purpose of the research presented in this dissertation is to determine if the FAA can pursue a resource management strategy that will support the current radar-based Air Traffic Control (ATC) system as well as a Global Positioning Satellite (GPS)-based ATC system required by the SATS. The research centered around the use of the System Dynamics modeling methodology to determine the future behavior of the principle components of the ATC system over time. The research included a model of the ATC system consisting of people, facilities, equipment, airports, aircraft, the FAA budget, and the Airport and Airways Trust Fund. The model generated system performance behavior used to evaluate three scenarios. The first scenario depicted the base case behavior of the system if the FAA continued its current resource management practices. The second scenario depicted the behavior of the system if the FAA emphasized development of GPS-based ATC systems. The third scenario depicted a combined resource management strategy that supplemented radar systems with GPS systems. The findings of the research were that the FAA must pursue a resource management strategy that primarily funds a radar-based ATC system and directs lesser funding toward a GPS-based supplemental ATC system. The most significant contribution of this research was the insight and understanding gained of how

  12. Research for electric energy systems

    NASA Astrophysics Data System (ADS)

    Anderson, W. E.

    1992-06-01

    This report documents the technical progress in the four investigations which make up the project 'Support of Research Projects for Electrical Energy Systems', Department of Energy Task Order Number 137, funded by the US Department of Energy and performed by the Electricity Division of the National Institute of Standards and Technology (NIST). The first investigation is concerned with the measurement of magnetic fields in support of epidemiogical and in vitro studies of biological field effects. The second investigation is concerned with two different activities: the production of S2F10 in negative corona in SF6 and the measurement of electron scattering and dissociative electron attachment cross sections for SF6 and its electrical by-products. The third investigation is also concerned with tvo different activities: several liquids that are currently used or have potential for use as high voltage dielectrics are studied using conventional impulse breakdown measurement techniques and high-speed photography and advances in partial discharge measurement techniques are presented. The last investigation is concerned with the evaluation and improvement of methods for measuring fast transients in electrical power systems such as might be associated with an electromagnetic impulse.

  13. Future Air Force aircraft propulsion control systems: The extended summary paper

    NASA Technical Reports Server (NTRS)

    Skira, C. A.

    1980-01-01

    Hydromechanical control technology simply cannot compete against the performance benefits offered by electronics. Future military aircraft propulsion control systems will be full authority, digital electronic, microprocessor base systems. Anticipating the day when microprocessor technology will permit the integration and management of aircraft flight control, fire control and propulsion control systems, the Air Force Aero Propulsion Laboratory is developing control logic algorithms for a real time, adaptive control and diagnostic information system.

  14. Models and techniques for evaluating the effectiveness of aircraft computing systems

    NASA Technical Reports Server (NTRS)

    Meyer, J. F.

    1978-01-01

    The development of system models that can provide a basis for the formulation and evaluation of aircraft computer system effectiveness, the formulation of quantitative measures of system effectiveness, and the development of analytic and simulation techniques for evaluating the effectiveness of a proposed or existing aircraft computer are described. Specific topics covered include: system models; performability evaluation; capability and functional dependence; computation of trajectory set probabilities; and hierarchical modeling of an air transport mission.

  15. Solar Thermal Electricity Generating System

    NASA Astrophysics Data System (ADS)

    Mishra, Sambeet; Tripathy, Pratyasha

    2012-08-01

    A Solar Thermal Electricity generating system also known as Solar Thermal Power plant is an emerging renewable energy technology, where we generate the thermal energy by concentrating and converting the direct solar radiationat medium/high temperature (300∫C ñ 800∫C). The resulting thermal energy is then used in a thermodynamic cycleto produce electricity, by running a heat engine, which turns a generator to make electricity. Solar thermal power is currently paving the way for the most cost-effective solar technology on a large scale and is heading to establish a cleaner, pollution free and secured future. Photovoltaic (PV) and solar thermal technologies are two main ways of generating energy from the sun, which is considered the inexhaustible source of energy. PV converts sunlight directly into electricity whereas in Solar thermal technology, heat from the sun's rays is concentrated to heat a fluid, whose steam powers a generator that produces electricity. It is similar to the way fossil fuel-burning power plants work except that the steam is produced by the collected heat rather than from the combustion of fossil fuels. In order to generate electricity, five major varieties of solar thermal technologies used are:* Parabolic Trough Solar Electric Generating System (SEGS).* Central Receiver Power Plant.* Solar Chimney Power Plant.* Dish Sterling System.* Solar Pond Power Plant.Most parts of India,Asia experiences a clear sunny weather for about 250 to 300 days a year, because of its location in the equatorial sun belt of the earth, receiving fairly large amount of radiation as compared to many parts of the world especially Japan, Europe and the US where development and deployment of solar technologies is maximum.Whether accompanied with this benefit or not, usually we have to concentrate the solar radiation in order to compensate for the attenuation of solar radiation in its way to earthís surface, which results in from 63,2 GW/m2 at the Sun to 1 kW/m2 at

  16. Models and techniques for evaluating the effectiveness of aircraft computing systems

    NASA Technical Reports Server (NTRS)

    Meyer, J. F.

    1982-01-01

    Models, measures, and techniques for evaluating the effectiveness of aircraft computing systems were developed. By "effectiveness" in this context we mean the extent to which the user, i.e., a commercial air carrier, may expect to benefit from the computational tasks accomplished by a computing system in the environment of an advanced commercial aircraft. Thus, the concept of effectiveness involves aspects of system performance, reliability, and worth (value, benefit) which are appropriately integrated in the process of evaluating system effectiveness. Specifically, the primary objectives are: the development of system models that provide a basis for the formulation and evaluation of aircraft computer system effectiveness, the formulation of quantitative measures of system effectiveness, and the development of analytic and simulation techniques for evaluating the effectiveness of a proposed or existing aircraft computer.

  17. A low cost maritime control aircraft-ship-weapons system. [antiship missile defense

    NASA Technical Reports Server (NTRS)

    Fluk, H.

    1981-01-01

    It is pointed out that the long-range antiship standoff missile is emerging as the foremost threat on the seas. Delivered by high speed bombers, surface ships, and submarines, a missile attack can be mounted against selected targets from any point on the compass. An investigation is conducted regarding the configuration of a system which could most efficiently identify and destroy standoff threats before they launch their weapons. It is found that by using ships for carrying and launching missiles, and employing aircraft with a powerful radar only for search and missile directing operations, aircraft cost and weight can be greatly reduced. The employment of V/STOL aircraft in preference to other types of aircraft makes it possible to use ships of smaller size for carrying the aircraft. However, in order to obtain an all-weather operational capability for the system, ships are selected which are still big enough to display the required stability in heavy seas.

  18. Flight test of ARINC 741 configuration low gain SATCOM system on Boeing 747-400 aircraft

    NASA Astrophysics Data System (ADS)

    Murphy, Timothy A.; Stapleton, Brian P.

    The Boeing company conducted a flight test of a SATCOM system similar to the ARINC 741 configuration on a production model 747-400. A flight plan was specifically designed to test the system over a wide variety of satellite elevations and aircraft attitudes as well as over land and sea. Interface bit errors, signal quality and aircraft position and navigational inputs were all recorded as a function of time. Special aircraft maneuvers were performed to demonstrate the potential for shadowing by aircraft structures. Both a compass rose test and the flight test indicated that shadowing from the tail is insignificant for the 747-400. However, satellite elevation angles below the aircraft horizon during banking maneuvers were shown to have a significant deleterious effect on SATCOM communications.

  19. Flight test of ARINC 741 configuration low gain SATCOM system on Boeing 747-400 aircraft

    NASA Technical Reports Server (NTRS)

    Murphy, Timothy A.; Stapleton, Brian P.

    1990-01-01

    The Boeing company conducted a flight test of a SATCOM system similar to the ARINC 741 configuration on a production model 747-400. A flight plan was specifically designed to test the system over a wide variety of satellite elevations and aircraft attitudes as well as over land and sea. Interface bit errors, signal quality and aircraft position and navigational inputs were all recorded as a function of time. Special aircraft maneuvers were performed to demonstrate the potential for shadowing by aircraft structures. Both a compass rose test and the flight test indicated that shadowing from the tail is insignificant for the 747-400. However, satellite elevation angles below the aircraft horizon during banking maneuvers were shown to have a significant deleterious effect on SATCOM communications.

  20. Application of variable structure system theory to aircraft flight control. [AV-8A and the Augmentor Wing Jet STOL Research Aircraft

    NASA Technical Reports Server (NTRS)

    Calise, A. J.; Kadushin, I.; Kramer, F.

    1981-01-01

    The current status of research on the application of variable structure system (VSS) theory to design aircraft flight control systems is summarized. Two aircraft types are currently being investigated: the Augmentor Wing Jet STOL Research Aircraft (AWJSRA), and AV-8A Harrier. The AWJSRA design considers automatic control of longitudinal dynamics during the landing phase. The main task for the AWJSRA is to design an automatic landing system that captures and tracks a localizer beam. The control task for the AV-8A is to track velocity commands in a hovering flight configuration. Much effort was devoted to developing computer programs that are needed to carry out VSS design in a multivariable frame work, and in becoming familiar with the dynamics and control problems associated with the aircraft types under investigation. Numerous VSS design schemes were explored, particularly for the AWJSRA. The approaches that appear best suited for these aircraft types are presented. Examples are given of the numerical results currently being generated.

  1. NASA-Langley Research Center's Aircraft Condition Analysis and Management System Implementation

    NASA Technical Reports Server (NTRS)

    Frye, Mark W.; Bailey, Roger M.; Jessup, Artie D.

    2004-01-01

    This document describes the hardware implementation design and architecture of Aeronautical Radio Incorporated (ARINC)'s Aircraft Condition Analysis and Management System (ACAMS), which was developed at NASA-Langley Research Center (LaRC) for use in its Airborne Research Integrated Experiments System (ARIES) Laboratory. This activity is part of NASA's Aviation Safety Program (AvSP), the Single Aircraft Accident Prevention (SAAP) project to develop safety-enabling technologies for aircraft and airborne systems. The fundamental intent of these technologies is to allow timely intervention or remediation to improve unsafe conditions before they become life threatening.

  2. Exploring Science Applications for Unmanned Aircraft Systems Aboard UNOLS Ships

    NASA Astrophysics Data System (ADS)

    Bailey, R.; Lachenmeier, T.; Hatfield, M. C.

    2014-12-01

    The University of Alaska Fairbanks has been expanding the use of small Unmanned Aircraft Systems (UAS) for science support from a variety of ships for several years. The ease and safety of flying from research vessels offers the science community lower cost access to overhead surveys of marine mammals without impact on sensitive populations, monitoring of AUV operations and collection of transmitted data, extensive surveys of sea ice during formation, melt, and sea temperatures through multiple seasons. As FAA expands access to the Arctic airspace over the Chukchi, Beaufort, and Bering Seas, the opportunities to employ UAS in science applications will become easier to exploit. This presentation describes the changes coming through new FAA rules, through the Alaska FAA Test Site, the Pan-Pacific UAS Test Range Complex which includes Oregon and Hawaii, and even Iceland. Airspace access advances associated with recent operations including the NASA-sponsored MIZOPEX, whale detection, and forming sea ice work in October will be presented, as well as a glider UAS connected to very high altitude balloons collecting atmospheric data. Development of safety procedures for use of UAS on UNOLS ships will be discussed.

  3. RSRA vertical drag test report. [rotor systems research aircraft

    NASA Technical Reports Server (NTRS)

    Flemming, R. J.

    1981-01-01

    The Rotor Systems Research Aircraft (RSRA), because of its ability to measure rotor loads, was used to conduct an experiment to determine vertical drag, tail rotor blockage, and thrust augmentation as affected by ground clearance and flight velocity. The RSRA was flown in the helicopter configuration at speeds from 0 to 15 knots for wheel heights from 5 to 150 feet, and to 60 knots out of ground effect. The vertical drag trends in hover, predicted by theory and shown in model tests, were generally confirmed. The OGE hover vertical drag is 4.0 percent, 1.1 percent greater than predicted. The vertical drag decreases rapidly as wheel height is reduced, and is zero at a wheel height of 6 feet. The vertical drag also decreases with forward speed, approaching zero at sixty knots. The test data show the effect of wheel height and forward speed on thrust, gross weight capability, and power, and provide the relationships for power and collective pitch at constant gross weight required for the simulation of helicopter takeoffs and landings.

  4. Analysis of LPFG sensor systems for aircraft wing drag optimization

    NASA Astrophysics Data System (ADS)

    Kazemi, Alex A.; Ishihara, Abe

    2014-09-01

    In normal fiber, the refractive indices of the core and cladding do not change along the length of the fiber; however, by inducing a periodic modulation of refractive index along the length in the core of the optical fiber, the optical fiber grating is produced. This exhibits very interesting spectral properties and for this reason we propose to develop and integrate a distributed sensor network based on long period fiber gratings (LPFGs) technology which has grating periods on the order of 100 μm to 1 mm to be embedded in the wing section of aircraft to measure bending and torsion in real-time in order to measure wing deformation of commercial airplanes resulting in extensive benefits such as reduced structural weight, mitigation of induced drag and lower fuel consumption which is fifty percent of total cost of operation for airline industry. Fiber optic sensors measurement capabilities are as vital as they are for other sensing technologies, but optical measurements differ in important ways. In this paper we focus on the testing and aviation requirements for LPFG sensors. We discuss the bases of aviation standards for fiber optic sensor measurements, and the quantities that are measured. Our main objective is to optimize the design for material, mechanical, optical and environmental requirements. We discuss the analysis and evaluation of extensive testing of LPFG sensor systems such as attenuation, environmental, humidity, fluid immersion, temperature cycling, aging, smoke, flammability, impact resistance, flexure endurance, tensile, vitiation and shock.

  5. Unmanned Aircraft Systems complement biologging in spatial ecology studies.

    PubMed

    Mulero-Pázmány, Margarita; Barasona, Jose Ángel; Acevedo, Pelayo; Vicente, Joaquín; Negro, Juan José

    2015-11-01

    The knowledge about the spatial ecology and distribution of organisms is important for both basic and applied science. Biologging is one of the most popular methods for obtaining information about spatial distribution of animals, but requires capturing the animals and is often limited by costs and data retrieval. Unmanned Aircraft Systems (UAS) have proven their efficacy for wildlife surveillance and habitat monitoring, but their potential contribution to the prediction of animal distribution patterns and abundance has not been thoroughly evaluated. In this study, we assess the usefulness of UAS overflights to (1) get data to model the distribution of free-ranging cattle for a comparison with results obtained from biologged (GPS-GSM collared) cattle and (2) predict species densities for a comparison with actual density in a protected area. UAS and biologging derived data models provided similar distribution patterns. Predictions from the UAS model overestimated cattle densities, which may be associated with higher aggregated distributions of this species. Overall, while the particular researcher interests and species characteristics will influence the method of choice for each study, we demonstrate here that UAS constitute a noninvasive methodology able to provide accurate spatial data useful for ecological research, wildlife management and rangeland planning. PMID:26640661

  6. The NASA aircraft noise prediction program improved propeller analysis system

    NASA Technical Reports Server (NTRS)

    Nguyen, L. Cathy

    1991-01-01

    The improvements and the modifications of the NASA Aircraft Noise Prediction Program (ANOPP) and the Propeller Analysis System (PAS) are described. Comparisons of the predictions and the test data are included in the case studies for the flat plate model in the Boundary Layer Module, for the effects of applying compressibility corrections to the lift and pressure coefficients, for the use of different weight factors in the Propeller Performance Module, for the use of the improved retarded time equation solution, and for the effect of the number grids in the Transonic Propeller Noise Module. The DNW tunnel test data of a propeller at different angles of attack and the Dowty Rotol data are compared with ANOPP predictions. The effect of the number of grids on the Transonic Propeller Noise Module predictions and the comparison of ANOPP TPN and DFP-ATP codes are studied. In addition to the above impact studies, the transonic propeller noise predictions for the SR-7, the UDF front rotor, and the support of the enroute noise test program are included.

  7. Status of display systems in the A-10A aircraft

    NASA Astrophysics Data System (ADS)

    Wodke, Kenneth E.; Hopper, Darrel G.

    2001-09-01

    The report scope covers the displays and controls at the pilot's crewstation on the current model Air Force A-10A and OA-10A aircraft. A description of an electronic display and an electronic control panel that have come to be of concern to the Air Force Air Combat Command (ACC) are included in the Funded Display Replacement Programs discussion. The display, which is a monochrome cathode ray tube (CRT), and the control panel were designed some 30 years ago. Thus, it is necessary to insert new technologies to maintain the capability heretofore provided by those now out of favor with the commercial sector. With this paper we begin a look at the status of displays in the A-10, which may remain in inventory until about 2030 according to current plans. From a component electronics technology perspective, such as displays, the A-10 provides several 10-year life cycle cost (LCC) planning cycles to consider multiple upgrades. Lessons learned from these projects can be applied both to other displays in the A-10 and other aging Department of Defense (DoD) weapon systems.

  8. Manned spacecraft electrical power systems

    NASA Technical Reports Server (NTRS)

    Simon, William E.; Nored, Donald L.

    1987-01-01

    A brief history of the development of electrical power systems from the earliest manned space flights illustrates a natural trend toward a growth of electrical power requirements and operational lifetimes with each succeeding space program. A review of the design philosophy and development experience associated with the Space Shuttle Orbiter electrical power system is presented, beginning with the state of technology at the conclusion of the Apollo Program. A discussion of prototype, verification, and qualification hardware is included, and several design improvements following the first Orbiter flight are described. The problems encountered, the scientific and engineering approaches used to meet the technological challenges, and the results obtained are stressed. Major technology barriers and their solutions are discussed, and a brief Orbiter flight experience summary of early Space Shuttle missions is included. A description of projected Space Station power requirements and candidate system concepts which could satisfy these anticipated needs is presented. Significant challenges different from Space Shuttle, innovative concepts and ideas, and station growth considerations are discussed. The Phase B Advanced Development hardware program is summarized and a status of Phase B preliminary tradeoff studies is presented.

  9. Problems related to the integration of fault tolerant aircraft electronic systems

    NASA Technical Reports Server (NTRS)

    Bannister, J. A.; Adlakha, V.; Triyedi, K.; Alspaugh, T. A., Jr.

    1982-01-01

    Problems related to the design of the hardware for an integrated aircraft electronic system are considered. Taxonomies of concurrent systems are reviewed and a new taxonomy is proposed. An informal methodology intended to identify feasible regions of the taxonomic design space is described. Specific tools are recommended for use in the methodology. Based on the methodology, a preliminary strawman integrated fault tolerant aircraft electronic system is proposed. Next, problems related to the programming and control of inegrated aircraft electronic systems are discussed. Issues of system resource management, including the scheduling and allocation of real time periodic tasks in a multiprocessor environment, are treated in detail. The role of software design in integrated fault tolerant aircraft electronic systems is discussed. Conclusions and recommendations for further work are included.

  10. Unmanned Aircraft Systems for Monitoring Department of the Interior Lands

    NASA Astrophysics Data System (ADS)

    Hutt, M. E.; Quirk, B.

    2013-12-01

    Unmanned Aircraft Systems (UAS) technology is quickly evolving and will have a significant impact on Earth science research. The U.S. Geological Survey (USGS) is conducting an operational test and evaluation of UAS to see how this technology supports the mission of the Department of the Interior (DOI). Over the last 4 years, the USGS, working with many partners, has been actively conducting proof of concept UAS operations, which are designed to evaluate the potential of UAS technology to support the mandated DOI scientific, resource and land management missions. UAS technology is being made available to monitor environmental conditions, analyze the impacts of climate change, respond to natural hazards, understand landscape change rates and consequences, conduct wildlife inventories and support related land management and law enforcement missions. Using small UAS (sUAS), the USGS is able to tailor solutions to meet project requirements by obtaining very high resolution video data, acquiring thermal imagery, detecting chemical plumes, and generating digital terrain models at a fraction of the cost of conventional surveying methods. UAS technology is providing a mechanism to collect timely remote sensing data at a low cost and at low risk over DOI lands that can be difficult to monitor and consequently enhances our ability to provide unbiased scientific information to better enable decision makers to make informed decisions. This presentation describes the UAS technology and infrastructure being employed, the application projects already accomplished, lessons learned and future of UAS within the DOI. We fully expect that by 2020 UAS will emerge as a primary platform for all DOI remote sensing applications. Much like the use of Internet technology, Geographic Information Systems (GIS) and Global Positioning Systems (GPS), UAS have the potential of enabling the DOI to be better stewards of the land.

  11. Electric vehicle energy management system

    NASA Astrophysics Data System (ADS)

    Alaoui, Chakib

    This thesis investigates and analyzes novel strategies for the optimum energy management of electric vehicles (EVs). These are aimed to maximize the useful life of the EV batteries and make the EV more practical in order to increase its acceptability to market. The first strategy concerns the right choice of the batteries for the EV according to the user's driving habits, which may vary. Tests conducted at the University of Massachusetts Lowell battery lab show that the batteries perform differently from one manufacturer to the other. The second strategy was to investigate the fast chargeability of different batteries, which leads to reduce the time needed to recharge the EV battery pack. Tests were conducted again to prove that only few battery types could be fast charged. Test data were used to design a fast battery charger that could be installed in an EV charging station. The third strategy was the design, fabrication and application of an Electric Vehicle Diagnostic and Rejuvenation System (EVDRS). This system is based on Mosfet Controlled Thyristors (MCTs). It is capable of quickly identifying any failing battery(s) within the EV pack and rejuvenating the whole battery pack without dismantling them and unloading them. A novel algorithm to rejuvenate Electric Vehicle Sealed Lead Acid Batteries is described. This rejuvenation extends the useful life of the batteries and makes the EV more competitive. The fourth strategy was to design a thermal management system for EV, which is crucial to the safe operation, and the achievement of normal/optimal performance of, electric vehicle (EV) batteries. A novel approach for EV thermal management, based on Pettier-Effect heat pumps, was designed, fabricated and tested in EV. It shows the application of this type of technology for thermal management of EVs.

  12. An electric control for an electrohydraulic active control aircraft landing gear

    NASA Technical Reports Server (NTRS)

    Ross, I.; Edson, R.

    1979-01-01

    An electronic controller for an electrohydraulic active control aircraft landing gear was developed. Drop tests of a modified gear from a 2722 Kg (6000 lbm) class of airplane were conducted to illustrate controller performance. The results indicate that the active gear effects a force reduction, relative to that of the passive gear, from 9 to 31 percent depending on the aircraft sink speed and the static gear pressure.

  13. Propulsion Electric Grid Simulator (PEGS) for Future Turboelectric Distributed Propulsion Aircraft

    NASA Technical Reports Server (NTRS)

    Choi, Benjamin B.; Morrison, Carlos; Dever, Timothy; Brown, Gerald V.

    2014-01-01

    NASA Glenn Research Center, in collaboration with the aerospace industry and academia, has begun the development of technology for a future hybrid-wing body electric airplane with a turboelectric distributed propulsion (TeDP) system. It is essential to design a subscale system to emulate the TeDP power grid, which would enable rapid analysis and demonstration of the proof-of-concept of the TeDP electrical system. This paper describes how small electrical machines with their controllers can emulate all the components in a TeDP power train. The whole system model in Matlab/Simulink was first developed and tested in simulation, and the simulation results showed that system dynamic characteristics could be implemented by using the closed-loop control of the electric motor drive systems. Then we designed a subscale experimental system to emulate the entire power system from the turbine engine to the propulsive fans. Firstly, we built a system to emulate a gas turbine engine driving a generator, consisting of two permanent magnet (PM) motors with brushless motor drives, coupled by a shaft. We programmed the first motor and its drive to mimic the speed-torque characteristic of the gas turbine engine, while the second motor and drive act as a generator and produce a torque load on the first motor. Secondly, we built another system of two PM motors and drives to emulate a motor driving a propulsive fan. We programmed the first motor and drive to emulate a wound-rotor synchronous motor. The propulsive fan was emulated by implementing fan maps and flight conditions into the fourth motor and drive, which produce a torque load on the driving motor. The stator of each PM motor is designed to travel axially to change the coupling between rotor and stator. This feature allows the PM motor to more closely emulate a wound-rotor synchronous machine. These techniques can convert the plain motor system into a unique TeDP power grid emulator that enables real-time simulation performance

  14. Wide field of view laser beacon system for three-dimensional aircraft position measurement

    NASA Technical Reports Server (NTRS)

    Sweet, L. M.; Miles, R. B.; Webb, S. G.; Wong, E. Y.

    1981-01-01

    This paper presents a new wide field of view laser beacon system for measurement, in three dimensions, of aircraft or other remote objects. The system is developed for aircraft collision hazard warning independent of ground-based hardware, as well as for flight research, helicopter-assisted construction and rescue, and robotic manipulation applications. Accurate information describing the relative range, elevation, and azimuth of the aircraft are generated by the sweep of a low-power fan-shaped rotating laser beacon past an array of optical detectors. The system achieves a wide angle of acceptance of laser beacon light through use of compound parabolic concentrators, which collimate the light for spectral filtering to minimize solar interference. An on-board microprocessor system converts the pulse sequence to aircraft position in real time. System reliability and performance are enhanced through narrow pass filtering of the pulse signals, digital logic design to mask spurious signals, and adaptive modulation of trigger threshold levels.

  15. Recent developments in aircraft protection systems for laser guide star operations

    NASA Astrophysics Data System (ADS)

    Stomski, Paul J.; Murphy, Thomas W.; Campbell, Randy

    2012-07-01

    The astronomical community's use of high power laser guide star adaptive optics (LGS-AO) systems presents a potential hazard to aviation. Historically, the most common and trusted means of protecting aircraft and their occupants has been the use of safety observers (aka spotters) armed with shut-off switches. These safety observers watch for aircraft at risk and terminate laser propagation before the aircraft can be adversely affected by the laser. Efforts to develop safer and more cost-effective automated aircraft protection systems for use by the astronomical community have been inhibited by both technological and regulatory challenges. This paper discusses recent developments in these two areas. Specifically, with regard to regulation and guidance we discuss the 2011 release of AS-6029 by the SAE as well as the potential impact of RTCA DO-278A. With regard to the recent developments in the technology used to protect aircraft from laser illumination, we discuss the novel Transponder Based Aircraft Detection (TBAD) system being installed at W. M. Keck Observatory (WMKO). Finally, we discuss our strategy for evaluating TBAD compliance with the regulations and for seeking appropriate approvals for LGS operations at WMKO using a fully automated, flexibly configured, multi-tier aircraft protection system incorporating this new technology.

  16. Design of an Electric Propulsion System for SCEPTOR

    NASA Technical Reports Server (NTRS)

    Dubois, Arthur; van der Geest, Martin; Bevirt, JoeBen; Clarke, Sean; Christie, Robert J.; Borer, Nicholas K.

    2016-01-01

    The rise of electric propulsion systems has pushed aircraft designers towards new and potentially transformative concepts. As part of this effort, NASA is leading the SCEPTOR program which aims at designing a fully electric distributed propulsion general aviation aircraft. This article highlights critical aspects of the design of SCEPTOR's propulsion system conceived at Joby Aviation in partnership with NASA, including motor electromagnetic design and optimization as well as cooling system integration. The motor is designed with a finite element based multi-objective optimization approach. This provides insight into important design tradeoffs such as mass versus efficiency, and enables a detailed quantitative comparison between different motor topologies. Secondly, a complete design and Computational Fluid Dynamics analysis of the air breathing cooling system is presented. The cooling system is fully integrated into the nacelle, contains little to no moving parts and only incurs a small drag penalty. Several concepts are considered and compared over a range of operating conditions. The study presents trade-offs between various parameters such as cooling efficiency, drag, mechanical simplicity and robustness.

  17. 14 CFR Special Federal Aviation... - Rules for use of portable oxygen concentrator systems on board aircraft

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Concentrator: means the AirSep FreeStyle, AirSep LifeStyle, Delphi RS-00400, Inogen One, Invacare XPO2... oxygen concentrator device, except the AirSep FreeStyle, AirSep LifeStyle, Delphi RS-00400, Inogen One... electrical, navigation or communication equipment on the aircraft on which the device is to be used; (2)...

  18. Evaluation of laminar flow control systems for subsonic commercial transport aircraft: Executive summary

    NASA Technical Reports Server (NTRS)

    Pearce, W. E.

    1982-01-01

    An evaluation was made of laminar flow control (LFC) system concepts for subsonic commercial transport aircraft. Configuration design studies, performance analyses, fabrication development, structural testing, wind tunnel testing, and contamination-avoidance techniques were included. As a result of trade studies, a configuration with LFC on the upper wing surface only, utilizing an electron beam-perforated suction surface, and employing a retractable high-lift shield for contamination avoidance, was selected as the most practical LFC system. The LFC aircraft was then compared with an advanced turbulent aircraft designed for the same mission. This comparison indicated significant fuel savings.

  19. Evaluation of laminar flow control systems concepts for subsonic commercial transport aircraft

    NASA Technical Reports Server (NTRS)

    Pearce, W. E.

    1983-01-01

    An evaluation was made of laminar flow control (LFC) system concepts for subsonic commercial transport aircraft. Configuration design studies, performance analyses, fabrication development, structural testing, wind tunnel testing, and contamination-avoidance techniques were included. As a result of trade studies, a configuration with LFC on the upper wing surface only, utilizing an electron beam-perforated suction surface, and employing a retractable high-lift shield for contamination avoidance, was selected as the most practical LFC system. The LFC aircraft was then compared with an advanced turbulent aircraft designed for the same mission. This comparison indicated significant fuel savings and reduced direct operating cost benefits would result from using LFC.

  20. Nonlinear control design for slightly nonminimum phase systems - Application to V/STOL aircraft

    NASA Technical Reports Server (NTRS)

    Hauser, John; Sastry, Shankar; Meyer, George

    1992-01-01

    The paper describes the application of techniques of exact I/O linearization of nonlinear control systems to the flight control of V/STOL aircraft. It is seen that the application of the theory to this example is not straightforward; in particular, the direct application of the theory yielded an undesirable controller. The situation was remedied by neglecting the coupling between the rolling moment input to the aircraft dynamics and the dynamics along the y-axis. An approximate I/O linearization procedure developed for slightly nonminimum phase nonlinear systems is shown to be effective for V/STOL aircraft.

  1. Apollo Lunar Module Electrical Power System Overview

    NASA Technical Reports Server (NTRS)

    Interbartolo, Michael

    2009-01-01

    Objectives include: a) Describe LM Electrical System original specifications; b) Describe the decision to change from fuel cells to batteries and other changes; c) Describe the Electrical system; and d) Describe the Apollo 13 failure from the LM perspective.

  2. Research for Electric Energy Systems

    SciTech Connect

    Anderson, W.E.

    1991-06-01

    This report documents the technical progress in investigations. The first investigation is concerned with the measurement of magnetic fields in support of epidemiogical and in vitro studies of biological field effects. NIST cohosted a workshop on exposure and biological parameters that should be considered during the vitro studies with extremely low frequency (ELF) magnetic and electric fields. Also, equations were developed to predict the magnetic field in a parallel plate magnetic field exposure system. The second investigation is concerned with two different activities: the detection of trace levels of S{sub 2}F{sub 10} in SF{sub 6} and the development of an improved stochastic analyzer for pulsating phenomena (SAPP). The detection of S{sub 2}F{sub 10} in the presence of SF{sub 6} using mass-spectrometric detection coupled to a gas chromatograph is difficult because of the similar mass spectra. A technique is described that enables the detection of S{sub 2}F{sub 10} in gaseous SF{sub 6} down to the ppb level using a modified gas chromatograph-mass spectrometer. The new system was applied to an investigation of the stochastic behavior of negative corona (Trichel pulses) and the effect of a dielectric barrier on these discharges. The third investigation is concerned with breakdown and prebreakdown phenomena in liquid dielectrics. The activity reported here was a study of negative steamers preceding electric breakdown in hexanes. Using the image preserving optical delay, the growth of the streamers associated with partial discharges at a point cathode are photographed at high magnification. The last investigation is concerned with the evaluation and improvement of methods for measuring fast transients in electrical power systems such as might be associated with an electromagnetic impulse. A compact resistive divider, NIST4, was designed. It is anticipated that this divider together with some Kerr electro-optical devices will be used as the reference system at NIST.

  3. ELECTRICAL SUPPORT SYSTEM DESCRIPTION DOCUMENT

    SciTech Connect

    S. Roy

    2004-06-24

    The purpose of this revision of the System Design Description (SDD) is to establish requirements that drive the design of the electrical support system and their bases to allow the design effort to proceed to License Application. This SDD is a living document that will be revised at strategic points as the design matures over time. This SDD identifies the requirements and describes the system design as they exist at this time, with emphasis on those attributes of the design provided to meet the requirements. This SDD has been developed to be an engineering tool for design control. Accordingly, the primary audience/users are design engineers. This type of SDD both ''leads'' and ''trails'' the design process. It leads the design process with regard to the flow down of upper tier requirements onto the system. Knowledge of these requirements is essential in performing the design process. The SDD trails the design with regard to the description of the system. The description provided in the SDD is a reflection of the results of the design process to date. Functional and operational requirements applicable to electrical support systems are obtained from the ''Project Functional and Operational Requirements'' (F&OR) (Siddoway 2003). Other requirements to support the design process have been taken from higher-level requirements documents such as the ''Project Design Criteria Document'' (PDC) (Doraswamy 2004), and fire hazards analyses. The above-mentioned low-level documents address ''Project Requirements Document'' (PRD) (Canon and Leitner 2003) requirements. This SDD contains several appendices that include supporting information. Appendix B lists key system charts, diagrams, drawings, and lists, and Appendix C includes a list of system procedures.

  4. 76 FR 75565 - NASA Advisory Council; Aeronautics Committee; Unmanned Aircraft Systems (UAS) Subcommittee Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-02

    ... From the Federal Register Online via the Government Publishing Office NATIONAL AERONAUTICS AND SPACE ADMINISTRATION NASA Advisory Council; Aeronautics Committee; Unmanned Aircraft Systems (UAS) Subcommittee Meeting AGENCY: National Aeronautics and Space Administration. ACTION: Notice of Meeting....

  5. Flight research capabilities of the NASA/Army rotor systems research aircraft

    NASA Technical Reports Server (NTRS)

    White, S., Jr.; Condon, G. W.

    1978-01-01

    A description is given of the capabilities and limitations of the Rotor Systems Research Aircraft (RSRA) that was demonstrated during the development contract, and assesses the expected research capabilities of the RSRA on delivery to the government.

  6. 78 FR 18932 - Public Meeting: Unmanned Aircraft Systems Test Site Program; Privacy Approach

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-28

    ... the Federal Register on February 22, 2013 (78 FR 12259), Docket No. FAA-2013-0061. In that document... operation of unmanned aircraft systems within the test site program (78 FR 12259). The proposed...

  7. Transport Aircraft System Identification from Wind Tunnel Data

    NASA Technical Reports Server (NTRS)

    Murphy, Patrick C.; Klein, Vladislav

    2008-01-01

    Recent studies have been undertaken to investigate and develop aerodynamic models that predict aircraft response in nonlinear unsteady flight regimes for transport configurations. The models retain conventional static and rotary dynamic terms but replace conventional acceleration terms with more general indicial functions. In the Integrated Resilient Aircraft Controls project of the NASA Aviation Safety Program one aspect of the research is to apply these current developments to transport configurations to facilitate development of advanced controls technology. This paper describes initial application of a more general modeling methodology to the NASA Langley Generic Transport Model, a sub-scale flight test vehicle.

  8. Sense-and-Avoid Equivalent Level of Safety Definition for Unmanned Aircraft Systems. Revision 9

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Since unmanned aircraft do not have a pilot on-board the aircraft, they cannot literally comply with the "see and avoid" requirement beyond a short distance from the location of the unmanned pilot. No performance standards are presently defined for unmanned Sense and Avoid systems, and the FAA has no published approval criteria for a collision avoidance system. Before the FAA can develop the necessary guidance (rules / regulations / policy) regarding the see-and-avoid requirements for Unmanned Aircraft Systems (UAS), a concise understanding of the term "equivalent level of safety" must be attained. Since this term is open to interpretation, the UAS industry and FAA need to come to an agreement on how this term can be defined and applied for a safe and acceptable collision avoidance capability for unmanned aircraft. Defining an equivalent level of safety (ELOS) for sense and avoid is one of the first steps in understanding the requirement and developing a collision avoidance capability. This document provides a functional level definition of see-and-avoid as it applies to unmanned aircraft. The sense and avoid ELOS definition is intended as a bridge between the see and avoid requirement and the system level requirements for unmanned aircraft sense and avoid systems. Sense and avoid ELOS is defined in a rather abstract way, meaning that it is not technology or system specific, and the definition provides key parameters (and a context for those parameters) to focus the development of cooperative and non-cooperative sense and avoid system requirements.

  9. Modeling, design and energy management of fuel cell systems for aircraft

    NASA Astrophysics Data System (ADS)

    Bradley, Thomas Heenan

    Fuel cell powered aircraft have been of long term interest to the aviation community because of their potential for improved performance and environmental compatibility. Only recently have improvements in the technological readiness of fuel cell powerplants enabled the first aviation applications of fuel cell technology. Based on the results of conceptual design studies and a few technology demonstration projects, there has emerged a widespread understanding of the importance of fuel cell powerplants for near-term and future aviation applications. Despite this, many aspects of the performance, design and construction of robust and optimized fuel cell powered aircraft have not been fully explored. This goal of this research then is to develop an improved understanding of the performance, design characteristics, design tradeoffs and viability of fuel cell powerplants for aviation applications. To accomplish these goals, new modeling, design, and experimental tools are developed, validated and applied to the design of fuel cell powered unmanned aerial vehicles. First, a general sub-system model of fuel cell powerplant performance, mass and geometry is derived from experimental and theoretical investigations of a fuel cell powerplant that is developed in hardware. These validated fuel cell subsystem models are then incorporated into a computer-based, application-integrated, parametric, and optimizeable design environment that allows for the concurrent design of the aircraft and fuel cell powerplant. The advanced modeling and design techniques required for modern aircraft design (including multi-disciplinary analysis, performance optimization under uncertainty and system performance validation), are applied at the fuel cell subsystem level and are linked to aircraft performance and design metrics. These tools and methods are then applied to the analysis and design of fuel cell powered aircraft in a series of case studies and design experiments. Based on the results of

  10. Engine-integrated solid oxide fuel cells for efficient electrical power generation on aircraft

    NASA Astrophysics Data System (ADS)

    Waters, Daniel F.; Cadou, Christopher P.

    2015-06-01

    This work investigates the use of engine-integrated catalytic partial oxidation (CPOx) reactors and solid oxide fuel cells (SOFCs) to reduce fuel burn in vehicles with large electrical loads like sensor-laden unmanned air vehicles. Thermodynamic models of SOFCs, CPOx reactors, and three gas turbine (GT) engine types (turbojet, combined exhaust turbofan, separate exhaust turbofan) are developed and checked against relevant data and source material. Fuel efficiency is increased by 4% and 8% in the 50 kW and 90 kW separate exhaust turbofan systems respectively at only modest cost in specific power (8% and 13% reductions respectively). Similar results are achieved in other engine types. An additional benefit of hybridization is the ability to provide more electric power (factors of 3 or more in some cases) than generator-based systems before encountering turbine inlet temperature limits. A sensitivity analysis shows that the most important parameters affecting the system's performance are operating voltage, percent fuel oxidation, and SOFC assembly air flows. Taken together, this study shows that it is possible to create a GT-SOFC hybrid where the GT mitigates balance of plant losses and the SOFC raises overall system efficiency. The result is a synergistic system with better overall performance than stand-alone components.

  11. Powertrain system for a hybrid electric vehicle

    DOEpatents

    Reed, Jr., Richard G.; Boberg, Evan S.; Lawrie, Robert E.; Castaing, Francois J.

    1999-08-31

    A hybrid electric powertrain system is provided including an electric motor/generator drivingly engaged with the drive shaft of a transmission. The electric is utilized for synchronizing the rotation of the drive shaft with the driven shaft during gear shift operations. In addition, a mild hybrid concept is provided which utilizes a smaller electric motor than typical hybrid powertrain systems. Because the electric motor is drivingly engaged with the drive shaft of the transmission, the electric motor/generator is driven at high speed even when the vehicle speed is low so that the electric motor/generator provides more efficient regeneration.

  12. Powertrain system for a hybrid electric vehicle

    DOEpatents

    Reed, R.G. Jr.; Boberg, E.S.; Lawrie, R.E.; Castaing, F.J.

    1999-08-31

    A hybrid electric powertrain system is provided including an electric motor/generator drivingly engaged with the drive shaft of a transmission. The electric is utilized for synchronizing the rotation of the drive shaft with the driven shaft during gear shift operations. In addition, a mild hybrid concept is provided which utilizes a smaller electric motor than typical hybrid powertrain systems. Because the electric motor is drivingly engaged with the drive shaft of the transmission, the electric motor/generator is driven at high speed even when the vehicle speed is low so that the electric motor/generator provides more efficient regeneration. 34 figs.

  13. Ignitor Electrical Power Supply System

    NASA Astrophysics Data System (ADS)

    Coletti, Alberto; Coletti, Roberto; Costa, Pietro; Maffia, Giuseppe; Ramogida, Giuseppe; Roccella, Massimo; Santinelli, Maurizio; Starace, Fabio

    2004-11-01

    An iterative optimization process to reduce the total installed electrical power required for Ignitor has been performed, bringing its value down to about 70% of that estimated originally. Ignitor is planned to be installed within the 400 kV Station of Rondissone (near Turin). The required electrical power (1000 MVA / 320 MVAr, including 480 MVAr locally compensated through static system, SVC) has been demonstrated by the technical authority GRTN to be compatible with the Grid capability. The magnet systems of Ignitor are supplied by means of a set of 14, 12 pulse, current regulated, sequentially or internal freewheeling controlled, fully static power amplifier units which are installed inside standard, outdoor-kind containers, located near to the related step-down transformers. Each container can house up to 100 MW, 2x12 pulse power amplifier units. The connection between the power amplifiers and the machine is performed by means of coaxial, outdoor-kind, segregated bus-bars. These choices make the whole power supply system as flexible as possible in terms of the overall layout of the Ignitor plant.

  14. Turboelectric Aircraft Drive Key Performance Parameters and Functional Requirements

    NASA Technical Reports Server (NTRS)

    Jansen, Ralph H.; Brown, Gerald V.; Felder, James L.; Duffy, Kirsten P.

    2016-01-01

    The purpose of this paper is to propose specific power and efficiency as the key performance parameters for a turboelectric aircraft power system and investigate their impact on the overall aircraft. Key functional requirements are identified that impact the power system design. Breguet range equations for a base aircraft and a turboelectric aircraft are found. The benefits and costs that may result from the turboelectric system are enumerated. A break-even analysis is conducted to find the minimum allowable electric drive specific power and efficiency that can preserve the range, initial weight, operating empty weight, and payload weight of the base aircraft.

  15. Turboelectric Aircraft Drive Key Performance Parameters and Functional Requirements

    NASA Technical Reports Server (NTRS)

    Jansen, Ralph; Brown, Gerald V.; Felder, James L.; Duffy, Kirsten P.

    2015-01-01

    The purpose of this presentation is to propose specific power and efficiency as the key performance parameters for a turboelectric aircraft power system and investigate their impact on the overall aircraft. Key functional requirements are identified that impact the power system design. Breguet range equations for a base aircraft and a turboelectric aircraft are found. The benefits and costs that may result from the turboelectric system are enumerated. A break-even analysis is conducted to find the minimum allowable electric drive specific power and efficiency that can preserve the range, initial weight, operating empty weight, and payload weight of the base aircraft.

  16. Turboelectric Aircraft Drive Key Performance Parameters and Functional Requirements

    NASA Technical Reports Server (NTRS)

    Jansen, Ralph H.; Brown, Gerald V.; Felder, James L.; Duffy, Kirsten P.

    2015-01-01

    The purpose of this paper is to propose specific power and efficiency as the key performance parameters for a turboelectric aircraft power system and investigate their impact on the overall aircraft. Key functional requirements are identified that impact the power system design. Breguet range equations for a base aircraft and a turboelectric aircraft are found. The benefits and costs that may result from the turboelectric system are enumerated. A break-even analysis is conducted to find the minimum allowable electric drive specific power and efficiency that can preserve the range, initial weight, operating empty weight, and payload weight of the base aircraft.

  17. Advanced control for airbreathing engines, volume 2: General Electric aircraft engines

    NASA Technical Reports Server (NTRS)

    Bansal, Indar

    1993-01-01

    The application of advanced control concepts to air breathing engines may yield significant improvements in aircraft/engine performance and operability. Screening studies of advanced control concepts for air breathing engines were conducted by three major domestic aircraft engine manufacturers to determine the potential impact of concepts on turbine engine performance and operability. The purpose of the studies was to identify concepts which offered high potential yet may incur high research and development risk. A target suite of proposed advanced control concepts was formulated and evaluated in a two phase study to quantify each concept's impact on desired engine characteristics. To aid in the evaluation specific aircraft/engine combinations were considered: a Military High Performance Fighter mission, a High Speed Civil Transport mission, and a Civil Tiltrotor mission. Each of the advanced control concepts considered in the study are defined and described. The concept potential impact on engine performance was determined. Relevant figures of merit on which to evaluate the concepts are determined. Finally, the concepts are ranked with respect to the target aircraft/engine missions. A final report describing the screening studies was prepared by each engine manufacturer. Volume 2 of these reports describes the studies performed by GE Aircraft Engines.

  18. Progress of Aircraft System Noise Assessment with Uncertainty Quantification for the Environmentally Responsible Aviation Project

    NASA Technical Reports Server (NTRS)

    Thomas, Russell H.; Burley, Casey L.; Guo, Yueping

    2016-01-01

    Aircraft system noise predictions have been performed for NASA modeled hybrid wing body aircraft advanced concepts with 2025 entry-into-service technology assumptions. The system noise predictions developed over a period from 2009 to 2016 as a result of improved modeling of the aircraft concepts, design changes, technology development, flight path modeling, and the use of extensive integrated system level experimental data. In addition, the system noise prediction models and process have been improved in many ways. An additional process is developed here for quantifying the uncertainty with a 95% confidence level. This uncertainty applies only to the aircraft system noise prediction process. For three points in time during this period, the vehicle designs, technologies, and noise prediction process are documented. For each of the three predictions, and with the information available at each of those points in time, the uncertainty is quantified using the direct Monte Carlo method with 10,000 simulations. For the prediction of cumulative noise of an advanced aircraft at the conceptual level of design, the total uncertainty band has been reduced from 12.2 to 9.6 EPNL dB. A value of 3.6 EPNL dB is proposed as the lower limit of uncertainty possible for the cumulative system noise prediction of an advanced aircraft concept.

  19. Registration and Marking Requirements for UAS. Unmanned Aircraft System (UAS) Registration

    NASA Technical Reports Server (NTRS)

    2005-01-01

    The registration of an aircraft is a prerequisite for issuance of a U.S. certificate of airworthiness by the FAA. The procedures and requirements for aircraft registration, and the subsequent issuance of registration numbers, are contained in FAR Part 47. However, the process/method(s) for applying the requirements of Parts 45 & 47 to Unmanned Aircraft Systems (UAS) has not been defined. This task resolved the application of 14 CFR Parts 45 and 47 to UAS. Key Findings: UAS are aircraft systems and as such the recommended approach to registration is to follow the same process for registration as manned aircraft. This will require manufacturers to comply with the requirements for 14 CFR 47, Aircraft Registration and 14 CFR 45, Identification and Registration Marking. In addition, only the UA should be identified with the N number registration markings. There should also be a documentation link showing the applicability of the control station and communication link to the UA. The documentation link can be in the form of a Type Certificate Data Sheet (TCDS) entry or a UAS logbook entry. The recommended process for the registration of UAS is similar to the manned aircraft process and is outlined in a 6-step process in the paper.

  20. Auralization of Hybrid Wing Body Aircraft Flyover Noise from System Noise Predictions

    NASA Technical Reports Server (NTRS)

    Rizzi, Stephen A.; Aumann, Aric R.; Lopes, Leonvard V.; Burley, Casey L.

    2013-01-01

    System noise assessments of a state-of-the-art reference aircraft (similar to a Boeing 777-200ER with GE90-like turbofan engines) and several hybrid wing body (HWB) aircraft configurations were recently performed using NASA engine and aircraft system analysis tools. The HWB aircraft were sized to an equivalent mission as the reference aircraft and assessments were performed using measurements of airframe shielding from a series of propulsion airframe aeroacoustic experiments. The focus of this work is to auralize flyover noise from the reference aircraft and the best HWB configuration using source noise predictions and shielding data based largely on the earlier assessments. For each aircraft, three flyover conditions are auralized. These correspond to approach, sideline, and cutback operating states, but flown in straight and level flight trajectories. The auralizations are performed using synthesis and simulation tools developed at NASA. Audio and visual presentations are provided to allow the reader to experience the flyover from the perspective of a listener in the simulated environment.

  1. A knowledge based application of the extended aircraft interrogation and display system

    NASA Technical Reports Server (NTRS)

    Glover, Richard D.; Larson, Richard R.

    1991-01-01

    A family of multiple-processor ground support test equipment was used to test digital flight-control systems on high-performance research aircraft. A unit recently built for the F-18 high alpha research vehicle project is the latest model in a series called the extended aircraft interrogation and display system. The primary feature emphasized monitors the aircraft MIL-STD-1553B data buses and provides real-time engineering units displays of flight-control parameters. A customized software package was developed to provide real-time data interpretation based on rules embodied in a highly structured knowledge database. The configuration of this extended aircraft interrogation and display system is briefly described, and the evolution of the rule based package and its application to failure modes and effects testing on the F-18 high alpha research vehicle is discussed.

  2. Effect of broadened-specification fuels on aircraft engines and fuel systems

    NASA Technical Reports Server (NTRS)

    Rudey, R. A.

    1979-01-01

    A wide variety of studies on the potential effects of broadened-specification fuels on future aircraft engines and fuel systems are summarized. The compositions and characteristics of aircraft fuels that may be derived from current and future crude-oil sources are described, and the most critical properties that may effect aircraft engines and fuel systems are identified and discussed. The problems that are most likely to be encountered because of changes in selected fuel properties are explored; and the related effects on engine performance, component durability and maintenance, and aircraft fuel-system performance are examined. The ability of current technology to accept possible future fuel specification changes is assessed and selected technological advances that can reduce the severity of the potential problems are illustrated.

  3. Study of fuel systems for LH2-fueled subsonic transport aircraft, volume 1

    NASA Technical Reports Server (NTRS)

    Brewer, G. D.; Morris, R. E.; Davis, G. W.; Versaw, E. F.; Cunnington, G. R., Jr.; Riple, J. C.; Baerst, C. F.; Garmong, G.

    1978-01-01

    Several engine concepts examined to determine a preferred design which most effectively exploits the characteristics of hydrogen fuel in aircraft tanks received major emphasis. Many candidate designs of tank structure and cryogenic insulation systems were evaluated. Designs of all major elements of the aircraft fuel system including pumps, lines, valves, regulators, and heat exchangers received attention. Selected designs of boost pumps to be mounted in the LH2 tanks, and of a high pressure pump to be mounted on the engine were defined. A final design of LH2-fueled transport aircraft was established which incorporates a preferred design of fuel system. That aircraft was then compared with a conventionally fueled counterpart designed to equivalent technology standards.

  4. High-Lift Propeller System Configuration Selection for NASA's SCEPTOR Distributed Electric Propulsion Flight Demonstrator

    NASA Technical Reports Server (NTRS)

    Patterson, Michael D.; Derlaga, Joseph M.; Borer, Nicholas K.

    2016-01-01

    Although the primary function of propellers is typically to produce thrust, aircraft equipped with distributed electric propulsion (DEP) may utilize propellers whose main purpose is to act as a form of high-lift device. These \\high-lift propellers" can be placed upstream of wing such that, when the higher-velocity ow in the propellers' slipstreams interacts with the wing, the lift is increased. This technique is a main design feature of a new NASA advanced design project called Scalable Convergent Electric Propulsion Technology Operations Research (SCEPTOR). The goal of the SCEPTOR project is design, build, and y a DEP aircraft to demonstrate that such an aircraft can be much more ecient than conventional designs. This paper provides details into the high-lift propeller system con guration selection for the SCEPTOR ight demonstrator. The methods used in the high-lift propeller system conceptual design and the tradeo s considered in selecting the number of propellers are discussed.

  5. Solar energy thermally powered electrical generating system

    NASA Technical Reports Server (NTRS)

    Owens, William R. (Inventor)

    1989-01-01

    A thermally powered electrical generating system for use in a space vehicle is disclosed. The rate of storage in a thermal energy storage medium is controlled by varying the rate of generation and dissipation of electrical energy in a thermally powered electrical generating system which is powered from heat stored in the thermal energy storage medium without exceeding a maximum quantity of heat. A control system (10) varies the rate at which electrical energy is generated by the electrical generating system and the rate at which electrical energy is consumed by a variable parasitic electrical load to cause storage of an amount of thermal energy in the thermal energy storage system at the end of a period of insolation which is sufficient to satisfy the scheduled demand for electrical power to be generated during the next period of eclipse. The control system is based upon Kalman filter theory.

  6. Study of quiet turbofan STOL aircraft for short-haul transportation. Volume 6: Systems analysis

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A systems analysis of the quiet turbofan aircraft for short-haul transportation was conducted. The purpose of the study was to integrate the representative data generated by aircraft, market, and economic analyses. Activities of the study were to develop the approach and to refine the methodologies for analytic tradeoff, and sensitivity studies of propulsive lift conceptual aircraft and their performance in simulated regional airlines. The operations of appropriate airlines in each of six geographic regions of the United States were simulated. The offshore domestic regions were evaluated to provide a complete domestic evaluation of the STOL concept applicability.

  7. Design and evaluation of aircraft heat source systems for use with high-freezing point fuels

    NASA Technical Reports Server (NTRS)

    Pasion, A. J.

    1979-01-01

    The objectives were the design, performance and economic analyses of practical aircraft fuel heating systems that would permit the use of high freezing-point fuels on long-range aircraft. Two hypothetical hydrocarbon fuels with freezing points of -29 C and -18 C were used to represent the variation from current day jet fuels. A Boeing 747-200 with JT9D-7/7A engines was used as the baseline aircraft. A 9300 Km mission was used as the mission length from which the heat requirements to maintain the fuel above its freezing point was based.

  8. Systems analysis of the installation, mounting, and activation of emergency locator transmitters in general aviation aircraft

    NASA Technical Reports Server (NTRS)

    Hall, D. S.

    1980-01-01

    A development program was developed to design and improve the Emergency Locator Transmitter (ELT) transmitter and to improve the installation in the aircraft and its activation subsystem. There were 1135 general aviation fixed wing aircraft accident files reviewed. A detailed description of the damage to the aircraft was produced. The search aspects of these accidents were studied. As much information as possible about the ELT units in these cases was collected. The data should assist in establishing installation and mounting criteria, better design standards for activation subsystems, and requirements for the new ELT system design in the area of crashworthiness.

  9. Future of V/STOL aircraft systems: A survey of opinions

    NASA Technical Reports Server (NTRS)

    White, K. C.; Lampkin, B. A.; Andrews, H.

    1985-01-01

    The recent success of the British Harriers in the Falkland Islands conflict vividly underscored the potential of V/STOL aircraft in military operations in a difficult environment. Despite this apparent success of the Harrier, there has been a major decline of V/STOL funding in the research and development budgets of the U.S. government and industry. The recent funding history of V/STOL systems is examined. Responses to a questionnaire which asked the question, Should there be an operational V/STOL aircraft other than the AV-8A and AV-8B in the military aircraft fleet of the U.S.A.? are presented and discussed.

  10. Electrical system for a motor vehicle

    DOEpatents

    Tamor, Michael Alan

    1999-01-01

    In one embodiment of the present invention, an electrical system for a motor vehicle comprises a capacitor, an engine cranking motor coupled to receive motive power from the capacitor, a storage battery and an electrical generator having an electrical power output, the output coupled to provide electrical energy to the capacitor and to the storage battery. The electrical system also includes a resistor which limits current flow from the battery to the engine cranking motor. The electrical system further includes a diode which allows current flow through the diode from the generator to the battery but which blocks current flow through the diode from the battery to the cranking motor.

  11. Electrical system for a motor vehicle

    DOEpatents

    Tamor, M.A.

    1999-07-20

    In one embodiment of the present invention, an electrical system for a motor vehicle comprises a capacitor, an engine cranking motor coupled to receive motive power from the capacitor, a storage battery and an electrical generator having an electrical power output, the output coupled to provide electrical energy to the capacitor and to the storage battery. The electrical system also includes a resistor which limits current flow from the battery to the engine cranking motor. The electrical system further includes a diode which allows current flow through the diode from the generator to the battery but which blocks current flow through the diode from the battery to the cranking motor. 2 figs.

  12. End-to-end testing. [to verify electrical equipment failure due to carbon fibers released in aircraft-fuel fires

    NASA Technical Reports Server (NTRS)

    Pride, R. A.

    1979-01-01

    The principle objective of the kinds of demonstration tests that are discussed is to try to verify whether or not carbon fibers that are released by burning composite parts in an aircraft-fuel fires can produce failures in electrical equipment. A secondary objective discussed is to experimentally validate the analytical models for some of the key elements in the risk analysis. The approach to this demonstration testing is twofold: limited end-to-end test are to be conducted in a shock tube; and planning for some large outdoor burn tests is being done.

  13. Design Methodology for Multi-Element High-Lift Systems on Subsonic Civil Transport Aircraft

    NASA Technical Reports Server (NTRS)

    Pepper, R. S.; vanDam, C. P.

    1996-01-01

    The choice of a high-lift system is crucial in the preliminary design process of a subsonic civil transport aircraft. Its purpose is to increase the allowable aircraft weight or decrease the aircraft's wing area for a given takeoff and landing performance. However, the implementation of a high-lift system into a design must be done carefully, for it can improve the aerodynamic performance of an aircraft but may also drastically increase the aircraft empty weight. If designed properly, a high-lift system can improve the cost effectiveness of an aircraft by increasing the payload weight for a given takeoff and landing performance. This is why the design methodology for a high-lift system should incorporate aerodynamic performance, weight, and cost. The airframe industry has experienced rapid technological growth in recent years which has led to significant advances in high-lift systems. For this reason many existing design methodologies have become obsolete since they are based on outdated low Reynolds number wind-tunnel data and can no longer accurately predict the aerodynamic characteristics or weight of current multi-element wings. Therefore, a new design methodology has been created that reflects current aerodynamic, weight, and cost data and provides enough flexibility to allow incorporation of new data when it becomes available.

  14. A synergistic glance at the prospects of distributed propulsion technology and the electric aircraft concept for future unmanned air vehicles and commercial/military aviation

    NASA Astrophysics Data System (ADS)

    Gohardani, Amir S.

    2013-02-01

    Distributed propulsion is one of the revolutionary candidates for future aircraft propulsion. In this journal article, the potential role of distributed propulsion technology in future aviation is investigated. Following a historical journey that revisits distributed propulsion technology in unmanned air vehicles and military aircraft, features of this specific technology are highlighted in synergy with an electric aircraft concept and a first-of-a-kind comparison to commercial aircraft employing distributed propulsion arrangements. In light of propulsion-airframe integration and complementary technologies such as boundary layer ingestion, thrust vectoring and circulation control, transpired opportunities and challenges are addressed in addition to a number of identified research directions proposed for future aircraft. The motivation behind enhanced means of communication between engineers, researchers and scientists has stimulated a novel proposed definition for the distributed propulsion technology in aviation and is presented herein.

  15. Modeling of gas turbine - solid oxide fuel cell systems for combined propulsion and power on aircraft

    NASA Astrophysics Data System (ADS)

    Waters, Daniel Francis

    This dissertation investigates the use of gas turbine (GT) engine integrated solid oxide fuel cells (SOFCs) to reduce fuel burn in aircraft with large electrical loads like sensor-laden unmanned air vehicles (UAVs). The concept offers a number of advantages: the GT absorbs many SOFC balance of plant functions (supplying fuel, air, and heat to the fuel cell) thereby reducing the number of components in the system; the GT supplies fuel and pressurized air that significantly increases SOFC performance; heat and unreacted fuel from the SOFC are recaptured by the GT cycle offsetting system-level losses; good transient response of the GT cycle compensates for poor transient response of the SOFC. The net result is a system that can supply more electrical power more efficiently than comparable engine-generator systems with only modest (<10%) decrease in power density. Thermodynamic models of SOFCs, catalytic partial oxidation (CPOx) reactors, and three GT engine types (turbojet, combined exhaust turbofan, separate exhaust turbofan) are developed that account for equilibrium gas phase and electrochemical reaction, pressure losses, and heat losses in ways that capture `down-the-channel' effects (a level of fidelity necessary for making meaningful performance, mass, and volume estimates). Models are created in a NASA-developed environment called Numerical Propulsion System Simulation (NPSS). A sensitivity analysis identifies important design parameters and translates uncertainties in model parameters into uncertainties in overall performance. GT-SOFC integrations reduce fuel burn 3-4% in 50 kW systems on 35 kN rated engines (all types) with overall uncertainty <1%. Reductions of 15-20% are possible at the 200 kW power level. GT-SOFCs are also able to provide more electric power (factors >3 in some cases) than generator-based systems before encountering turbine inlet temperature limits. Aerodynamic drag effects of engine-airframe integration are by far the most important

  16. Hydrocarbon disperse systems in electric fields

    SciTech Connect

    Deinega, Y.F.

    1983-07-01

    On the basis of method for regulating the smooth adjustment of the charge of the disperse phase of hydrocarbon systems in electric fields from positive to negative values by means of surfactants, a schematic electrokinetic picture of the behavior of the systems is derived. Changes in the structure of the disperse systems in electric fields have a substantial effect on the rheological properties of the system. The effect of electric fields on the formation of crystallization-condensation structures, the mechanism of electrical conduction with a high rate of deformation, and the many practical applications of electrical effects on hydrocarbon disperse systems are also studied.

  17. Multiparameter radar and aircraft based studies of microphysical, kinematic, and electrical structure of convective clouds during CaPE

    NASA Astrophysics Data System (ADS)

    Bringi, V. N.

    1994-03-01

    Two storms from the 9 August, 1991 CaPE case were analyzed in-depth focusing on multiparameter radar signature evolution over 60 min. in coordination with 24 aircraft penetrations which provided particle image and electric field data together with vertical air motion, cloud water and other state parameters. A total of five discrete 'cells' were identified in the two storms and their life cycle fully documented. Collaboration with South Dakota School of Mines and University of Alabama at Huntsville has resulted in a full integration of aircraft image and field mill data (from SDSM&T T-28 aircraft) with vertical air motion from dual-Doppler wind synthesis (UAH). The cellular evolution starts with a warm rain phase where updrafts and a very low concentration of large drops dominate the cloud. As the supercooled drops rise in the updraft they freeze and acquire a water-coat possibly by collisions with other liquid drops. The multi-parameter radar signatures clearly identify this mixed-phase zone. The cloud thereafter gets electrified which may intensify to produce lightning depending on cloud vertical growth, and generation of updraft/ downdrafts.

  18. Changes in structural health monitoring system capability due to aircraft environmental factors

    NASA Astrophysics Data System (ADS)

    Kuhn, Jeffrey D.

    Structural Health Monitoring (SHM) promises to decrease the maintenance cost and increase the availability of aging aircraft fleets by fundamentally changing the way structural inspections are performed. But this promise can only be realized through the consistent and predictable performance of a SHM system throughout the entire remaining life of an aircraft. In a sensor-based SHM system, sensor signal changes are analyzed and interpreted to identify structural flaws. But aircraft environmental factors such as temperature fluctuations, cyclic strain and exposure to various aircraft fluids also have the potential to change SHM sensor signals, raising questions about long term SHM system capability. This research begins by analyzing the current USAF inspection paradigm, known aircraft environmental factors, representative structural inspection locations for the F-15 and C-130, and current SHM technologies. A design of experiments approach is used to build and execute an experiment to determine the effect of one aircraft environmental factor (cyclic strain) on a common SHM technology (PZT-based sensors). Analysis of the experimental results shows the sensors to be significantly affected by cyclic strain, and that the effects can be estimated using a power equation model. A "probability of detection (POD) degradation model" is then developed by extending existing nondestructive evaluation (NDE) POD analysis techniques. This model demonstrates how changes in sensor performance due to an aircraft environmental factor can be used to estimate the change in overall performance of the SHM system. This POD degradation model provides a common framework to predict changes in SHM system performance over the remaining life of an aircraft. An example combining the experimental results with an existing SHM POD analysis shows how the POD degradation model can be applied to current SHM research.

  19. Aircraft Environmental System Mechanic, 2-9. Block III--Aircraft Environmental Systems Units. Military Curriculum Materials for Vocational and Technical Education.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This publication contains a teaching guide and student instructional materials for conducting a high school or adult vocational education course to train persons to perform duties as an aircraft environmental systems mechanic. Course content has been adapted from a military course. The instructional design for this course is self-paced and/or…

  20. Study of aircraft in intraurban transportation systems, San Francisco Bay area

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The nine-county San Francisco Bay area is examined in two time periods (1975-1980 and 1985-1990) as a scenario for analyzing the characteristics of an intraurban, commuter-oriented aircraft transportation system. Aircraft have dominated the long-haul passenger market for some time, but efforts to penetrate the very-short-haul intraurban market have met with only token success. Yet, the characteristics of an aircraft transportation system-speed and flexibility-are very much needed to solve the transportation ills of our major urban areas. This study attempts to determine if the aircraft can contribute toward solving the transportation problems of major metropolitan areas and be economically viable in such an environment.

  1. Flight parameters monitoring system for tracking structural integrity of rotary-wing aircraft

    NASA Technical Reports Server (NTRS)

    Mohammadi, Jamshid; Olkiewicz, Craig

    1994-01-01

    Recent developments in advanced monitoring systems used in conjunction with tracking structural integrity of rotary-wing aircraft are explained. The paper describes: (1) an overview of rotary-wing aircraft flight parameters that are critical to the aircraft loading conditions and each parameter's specific requirements in terms of data collection and processing; (2) description of the monitoring system and its functions used in a survey of rotary-wing aircraft; and (3) description of the method of analysis used for the data. The paper presents a newly-developed method in compiling flight data. The method utilizes the maneuver sequence of events in several pre-identified flight conditions to describe various flight parameters at three specific weight ranges.

  2. A neural based intelligent flight control system for the NASA F-15 flight research aircraft

    NASA Technical Reports Server (NTRS)

    Urnes, James M.; Hoy, Stephen E.; Ladage, Robert N.; Stewart, James

    1993-01-01

    A flight control concept that can identify aircraft stability properties and continually optimize the aircraft flying qualities has been developed by McDonnell Aircraft Company under a contract with the NASA-Dryden Flight Research Facility. This flight concept, termed the Intelligent Flight Control System, utilizes Neural Network technology to identify the host aircraft stability and control properties during flight, and use this information to design on-line the control system feedback gains to provide continuous optimum flight response. This self-repairing capability can provide high performance flight maneuvering response throughout large flight envelopes, such as needed for the National Aerospace Plane. Moreover, achieving this response early in the vehicle's development schedule will save cost.

  3. Classification of Unmanned Aircraft Systems. UAS Classification/Categorization for Certification

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Category, class, and type designations are primary means to identify appropriate aircraft certification basis, operating rules/limitations, and pilot qualifications to operate in the National Airspace System (NAS). The question is whether UAS fit into existing aircraft categories or classes, or are unique enough to justify the creation of a new category/class. In addition, the characteristics or capabilities, which define when an UAS becomes a regulated aircraft, must also be decided. This issue focuses on UAS classification for certification purposes. Several approaches have been considered for classifying UAS. They basically group into either using a weight/mass basis, or a safety risk basis, factoring in the performance of the UAS, including where the UAS would operate. Under existing standards, aircraft must have a Type Certificate and Certificate of Airworthiness, in order to be used for "compensation or hire", a major difference from model aircraft. Newer technologies may make it possible for very small UAS to conduct commercial services, but that is left for a future discussion to extend the regulated aircraft to a lower level. The Access 5 position is that UAS are aircraft and should be regulated above the weight threshold differentiating them from model airplanes. The recommended classification grouping is summarized in a chart.

  4. The Small Aircraft Transportation System Higher Volume Operations (SATS HVO) Flight Experiment

    NASA Technical Reports Server (NTRS)

    Williams, Daniel M.; Murdoch, Jennifer L.; Adams, Catherine H.

    2005-01-01

    This paper provides a summary of conclusions from the Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) Flight Experiment which NASA conducted to determine pilot acceptability of the HVO concept for normal conditions. The SATS HVO concept improves efficiency at non-towered, non-radar airports in Instrument Meteorological Conditions (IMC) while achieving a level of safety equal to today s system. Reported are results from flight experiment data that indicate that the SATS HVO concept is viable. The success of the SATS HVO concept is based on acceptable pilot workload, performance, and subjective criteria when compared to the procedural control operations in use today at non-towered, non-radar controlled airfields in IMC. The HVO Flight Experiment, flown on NASA's Cirrus SR22, used a subset of the HVO Simulation Experiment scenarios and evaluation pilots in order to validate the simulation experiment results. HVO and Baseline (today s system) scenarios flown included: single aircraft arriving for a GPS non-precision approach; aircraft arriving for the approach with multiple traffic aircraft; and aircraft arriving for the approach with multiple traffic aircraft and then conducting a missed approach. Results reveal that all twelve low-time instrument-rated pilots preferred SATS HVO when compared to current procedural separation operations. These pilots also flew the HVO procedures safely and proficiently without additional workload in comparison to today s system (Baseline). Detailed results of pilot flight technical error, and their subjective assessments of workload and situation awareness are presented in this paper.

  5. 33 CFR 127.1107 - Electrical systems.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Electrical systems. 127.1107... Waterfront Facilities Handling Liquefied Hazardous Gas Design and Construction § 127.1107 Electrical systems. Electrical equipment and wiring must be of the kind specified by, and must be installed in accordance...

  6. 33 CFR 127.1107 - Electrical systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Electrical systems. 127.1107... Waterfront Facilities Handling Liquefied Hazardous Gas Design and Construction § 127.1107 Electrical systems. Electrical equipment and wiring must be of the kind specified by, and must be installed in accordance...

  7. 33 CFR 127.1107 - Electrical systems.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Electrical systems. 127.1107... Waterfront Facilities Handling Liquefied Hazardous Gas Design and Construction § 127.1107 Electrical systems. Electrical equipment and wiring must be of the kind specified by, and must be installed in accordance...

  8. 33 CFR 127.1107 - Electrical systems.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Electrical systems. 127.1107... Waterfront Facilities Handling Liquefied Hazardous Gas Design and Construction § 127.1107 Electrical systems. Electrical equipment and wiring must be of the kind specified by, and must be installed in accordance...

  9. Electrical Systems. FOS: Fundamentals of Service.

    ERIC Educational Resources Information Center

    John Deere Co., Moline, IL.

    This electrical systems manual is one of a series of power mechanics texts and visual aids for training in the servicing of electrical systems on mobile machines. Materials provide basic information and illustrations for use by vocational students and teachers as well as shop servicemen and laymen. The ten chapters focus on (1) Electricity: How It…

  10. Diesel Electrical Systems. Teacher Edition (Revised).

    ERIC Educational Resources Information Center

    Sprinkle, Tom; Huston, Jane, Ed.

    This module is one of a series of teaching guides that cover diesel mechanics. The module contains eight instructional units that cover the following topics: (1) introduction to electrical systems; (2) electrical circuits; (3) electrical indicator circuits; (4) storage batteries; (5) starting systems and circuits; (6) ignition circuits; (7)…

  11. A survey on electromagnetic interferences on aircraft avionics systems and a GSM on board system overview

    NASA Astrophysics Data System (ADS)

    Vinto, Natale; Tropea, Mauro; Fazio, Peppino; Voznak, Miroslav

    2014-05-01

    Recent years have been characterized by an increase in the air traffic. More attention over micro-economic and macroeconomic indexes would be strategic to gather and enhance the safety of a flight and customer needing, for communicating by wireless handhelds on-board aircrafts. Thus, European Telecommunications Standards Institute (ETSI) proposed a GSM On Board (GSMOBA) system as a possible solution, allowing mobile terminals to communicate through GSM system on aircraft, avoiding electromagnetic interferences with radio components aboard. The main issues are directly related with interferences that could spring-out when mobile terminals attempt to connect to ground BTS, from the airplane. This kind of system is able to resolve the problem in terms of conformance of Effective Isotropic Radiated Power (EIRP) limits, defined outside the aircraft, by using an On board BTS (OBTS) and modeling the relevant key RF parameters on the air. The main purpose of this work is to illustrate the state-of-the-art of literature and previous studies about the problem, giving also a good detail of technical and normative references.

  12. Transonic propulsion system integration analysis at McDonnell Aircraft Company

    NASA Technical Reports Server (NTRS)

    Cosner, Raymond R.

    1989-01-01

    The technology of Computational Fluid Dynamics (CFD) is becoming an important tool in the development of aircraft propulsion systems. Two of the most valuable features of CFD are: (1) quick acquisition of flow field data; and (2) complete description of flow fields, allowing detailed investigation of interactions. Current analysis methods complement wind tunnel testing in several ways. Herein, the discussion is focused on CFD methods. However, aircraft design studies need data from both CFD and wind tunnel testing. Each approach complements the other.

  13. Real-time fault monitoring for aircraft applications using quantitative simulation and expert systems

    NASA Technical Reports Server (NTRS)

    Schutte, Paul C.

    1989-01-01

    A fault monitoring concept called MONITAUR, which has been developed for aircraft applications at NASA-Langley, is described. MONITAUR was designed to provide a high-quality situational assessment of aircraft subsystems to other onboard software systems in abnormal situations. A nonreal-time implementation of MONITAUR was developed on a Symbolics 3650 Lisp Machine. Issues which must be addressed in the further development of MONITAUR are discussed.

  14. Synthesis from Design Requirements of a Hybrid System for Transport Aircraft Longitudinal Control. Volume 2

    NASA Technical Reports Server (NTRS)

    Hynes, Charles S.; Hardy, Gordon H.; Sherry, Lance

    2007-01-01

    Volume I of this report presents a new method for synthesizing hybrid systems directly from desi gn requirements, and applies the method to design of a hybrid system for longitudinal control of transport aircraft. The resulting system satisfies general requirement for safety and effectiveness specified a priori, enabling formal validation to be achieved. Volume II contains seven appendices intended to make the report accessible to readers with backgrounds in human factors, flight dynamics and control, and formal logic. Major design goals are (1) system design integrity based on proof of correctness at the design level, (2) significant simplification and cost reduction in system development and certification, and (3) improved operational efficiency, with significant alleviation of human-factors problems encountered by pilots in current transport aircraft. This report provides for the first time a firm technical basis for criteria governing design and certification of avionic systems for transport aircraft. It should be of primary interest to designers of next-generation avionic systems.

  15. Hybrid electric vehicle power management system

    DOEpatents

    Bissontz, Jay E.

    2015-08-25

    Level voltage levels/states of charge are maintained among a plurality of high voltage DC electrical storage devices/traction battery packs that are arrayed in series to support operation of a hybrid electric vehicle drive train. Each high voltage DC electrical storage device supports a high voltage power bus, to which at least one controllable load is connected, and at least a first lower voltage level electrical distribution system. The rate of power transfer from the high voltage DC electrical storage devices to the at least first lower voltage electrical distribution system is controlled by DC-DC converters.

  16. A system safety model for developmental aircraft programs

    NASA Technical Reports Server (NTRS)

    Amberboy, E. J.; Stokeld, R. L.

    1982-01-01

    Basic tenets of safety as applied to developmental aircraft programs are presented. The integration of safety into the project management aspects of planning, organizing, directing and controlling is illustrated by examples. The basis for project management use of safety and the relationship of these management functions to 'real-world' situations is presented. The rationale which led to the safety-related project decision and the lessons learned as they may apply to future projects are presented.

  17. Pathfinder aircraft in flight

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The unique Pathfinder solar-powered flying wing, is shown during a checkout flight from the Dryden Flight Research Center, Edwards, California. This two-hour low-altitude flight over Rogers Dry Lake, Nov. 19, 1996, served to test aircraft systems and functional procedures, according to officials of AeroVironment, Inc., Pathfinder's developer and operator. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus configuration. (See the Pathfinder Plus photos and project description.)

  18. Application of a cost/performance measurement system on a research aircraft project

    NASA Technical Reports Server (NTRS)

    Diehl, J. J.

    1978-01-01

    The fundamentals of the cost/performance management system used in the procurement of two tilt rotor aircraft for a joint NASA/Army research project are discussed. The contractor's reporting system and the GPO's analyses are examined. The use of this type of reporting system is assessed. Recommendations concerning the use of like systems on future projects are included.

  19. Power systems and requirements for the integration of smart structures into aircraft

    NASA Astrophysics Data System (ADS)

    Lockyer, Allen J.; Martin, Christopher A.; Lindner, Douglas K.; Walia, Paramjit S.

    2002-07-01

    Electrical power distribution for recently developed smart actuators becomes an important air-vehicle challenge if projected smart actuation benefits are to be met. Among the items under development are variable shape inlets and control surfaces that utilize shape memory alloys (SMA); full span, chord-wise and span-wise contouring trailing control surfaces that use SMA or piezoelectric materials for actuation; and other strain-based actuators for buffet load alleviation, flutter suppression and flow control. At first glance, such technologies afford overall vehicle performance improvement, however, integration system impacts have yet to be determined or quantified. Power systems to support smart structures initiatives are the focus of the current paper. The paper has been organized into five main topics for further discussion: (1) air-vehicle power system architectures - standard and advanced distribution concepts for actuators, (2) smart wing actuator power requirements and results - highlighting wind tunnel power measurements from shape memory alloy and piezoelectric ultrasonic motor actuated control surfaces and different dynamic pressure and angle of attack; (3) vehicle electromagnetic effects (EME) issues, (4) power supply design considerations for smart actuators - featuring the aircraft power and actuator interface, and (5) summary and conclusions.

  20. Aircraft Wake Vortex Spacing System (AVOSS) Performance Update and Validation Study

    NASA Technical Reports Server (NTRS)

    Rutishauser, David K.; OConnor, Cornelius J.

    2001-01-01

    An analysis has been performed on data generated from the two most recent field deployments of the Aircraft Wake VOrtex Spacing System (AVOSS). The AVOSS provides reduced aircraft spacing criteria for wake vortex avoidance as compared to the FAA spacing applied under Instrument Flight Rules (IFR). Several field deployments culminating in a system demonstration at Dallas Fort Worth (DFW) International Airport in the summer of 2000 were successful in showing a sound operational concept and the system's potential to provide a significant benefit to airport operations. For DFW, a predicted average throughput increase of 6% was observed. This increase implies 6 or 7 more aircraft on the ground in a one-hour period for DFW operations. Several studies of performance correlations to system configuration options, design options, and system inputs are also reported. The studies focus on the validation performance of the system.

  1. Indentation-Damage Visualization in CFRP by Resistive Heating: Analytical Verification of The Inspection of Aircraft Using Its Lightning Protection Systems

    NASA Astrophysics Data System (ADS)

    Suzuki, Yoshiro; Todoroki, Akira; Matsuzaki, Ryosuke; Mizutani, Yoshihiro

    Quick and automatic inspection of carbon fiber reinforced polymer (CFRP) aircraft after each flight would reduce the safety factor and allow for more flights. Visualization of impact damage was developed in an earlier study as an automatic self-monitoring method. The damaged area was visualized by selective and intense resistive heating based on its decreased through-thickness resistivity compared to undamaged areas. In the present study, the lightning protection system of a composite aircraft was used to apply a uniform electrical current distribution and electric heat to a large structure. Subsequent coupled thermal-electrical analyses showed that even small indentations (depth <0.15 mm) could be relatively easily detected in structures about 1 m in size.

  2. Electric vehicle system for charging and supplying electrical power

    DOEpatents

    Su, Gui Jia

    2010-06-08

    A power system that provides power between an energy storage device, an external charging-source/load, an onboard electrical power generator, and a vehicle drive shaft. The power system has at least one energy storage device electrically connected across a dc bus, at least one filter capacitor leg having at least one filter capacitor electrically connected across the dc bus, at least one power inverter/converter electrically connected across the dc bus, and at least one multiphase motor/generator having stator windings electrically connected at one end to form a neutral point and electrically connected on the other end to one of the power inverter/converters. A charging-sourcing selection socket is electrically connected to the neutral points and the external charging-source/load. At least one electronics controller is electrically connected to the charging-sourcing selection socket and at least one power inverter/converter. The switch legs in each of the inverter/converters selected by the charging-source/load socket collectively function as a single switch leg. The motor/generators function as an inductor.

  3. Rotor systems research aircraft of predesign study. Volume 1: Summary and conclusions

    NASA Technical Reports Server (NTRS)

    Linden, A. W.

    1972-01-01

    The results are summarized of a study to develop a versatile research aircraft for flight testing a wide variety of advanced helicopter and compound rotor systems. The aircraft is required to accept these rotors with minimal changes in the basic vehicle. Rotors envisioned for testing include conventional rotors plus variable geometry, variable twist, variable diameter, coaxial, jet flap, circulation control, and slowed rotors. Various disc loadings would be accommodated. The aircraft must be configured to measure performance more accurately than past test vehicles. In addition, the aircraft would have a wing to off load the rotor while measuring performance during lightly loaded conditions. It would have variable drag and propulsive force so that the rotor can be tested while producing different values of horizontal force.

  4. Conflict Prevention and Separation Assurance Method in the Small Aircraft Transportation System

    NASA Technical Reports Server (NTRS)

    Consiglio, Maria C.; Carreno, Victor A.; Williams, Daniel M.; Munoz, Cesar

    2005-01-01

    A multilayer approach to the prevention of conflicts due to the loss of aircraft-to-aircraft separation which relies on procedures and on-board automation was implemented as part of the SATS HVO Concept of Operations. The multilayer system gives pilots support and guidance during the execution of normal operations and advance warning for procedure deviations or off-nominal operations. This paper describes the major concept elements of this multilayer approach to separation assurance and conflict prevention and provides the rationale for its design. All the algorithms and functionality described in this paper have been implemented in an aircraft simulation in the NASA Langley Research Center s Air Traffic Operation Lab and on the NASA Cirrus SR22 research aircraft.

  5. Small Aircraft Transportation System, Higher Volume Operations Concept: Off-Nominal Operations

    NASA Technical Reports Server (NTRS)

    Abbott, Terence S.; Consiglio, Maria C.; Baxley, Brian T.; Williams, Daniel M.; Conway, Sheila R.

    2005-01-01

    This document expands the Small Aircraft Transportation System, (SATS) Higher Volume Operations (HVO) concept to include off-nominal conditions. The general philosophy underlying the HVO concept is the establishment of a newly defined area of flight operations called a Self-Controlled Area (SCA). During periods of poor weather, a block of airspace would be established around designated non-towered, non-radar airports. Aircraft flying enroute to a SATS airport would be on a standard instrument flight rules flight clearance with Air Traffic Control providing separation services. Within the SCA, pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft. Previous work developed the procedures for normal HVO operations. This document provides details for off-nominal and emergency procedures for situations that could be expected to occur in a future SCA.

  6. Mountain Search and Rescue with Remotely Piloted Aircraft Systems

    NASA Astrophysics Data System (ADS)

    Silvagni, Mario; Tonoli, Andrea; Zenerino, Enrico; Chiaberge, Marcello

    2016-04-01

    Remotely Piloted Aircraft Systems (RPAS) also known as Unmanned Aerial Systems (UAS) are nowadays becoming more and more popular in several applications. Even though a complete regulation is not yet available all over the world, researches, tests and some real case applications are wide spreading. These technologies can bring many benefits also to the mountain operations especially in emergencies and harsh environmental conditions, such as Search and Rescue (SAR) and avalanche rescue missions. In fact, during last decade, the number of people practicing winter sports in backcountry environment is increased and one of the greatest hazards for recreationists and professionals are avalanches. Often these accidents have severe consequences leading, mostly, to asphyxia-related death, which is confirmed by the hard drop of survival probability after ten minutes from the burying. Therefore, it is essential to minimize the time of burial. Modern avalanche beacon (ARTVA) interface guides the rescuer during the search phase reducing its time. Even if modern avalanche beacons are valid and reliable, the seeking range influences the rescue time. Furthermore, the environment and morphologic conditions of avalanches usually complicates the rescues. The recursive methodology of this kind of searching offers the opportunity to use automatic device like drones (RPAS). These systems allow performing all the required tasks autonomously, with high accuracy and without exposing the rescuers to additional risks due to secondary avalanches. The availability of highly integrated electronics and subsystems specifically meant for the applications, better batteries, miniaturized payload and, in general, affordable prices, has led to the availability of small RPAS with very good performances that can give interesting application opportunities in unconventional environments. The present work is one of the outcome from the experience made by the authors in RPAS fields and in Mechatronics

  7. A review and update of the NASA aircraft noise prediction program propeller analysis system

    NASA Technical Reports Server (NTRS)

    Golub, Robert A.; Nguyen, L. Cathy

    1989-01-01

    The National Aeronautics and Space Administration (NASA) Aircraft Noise Prediction Program (ANOPP) Propeller Analysis System (PAS) is a set of computational modules for predicting the aerodynamics, performance, and noise of propellers. The ANOPP PAS has the capability to predict noise levels for propeller aircraft certification and produce parametric scaling laws for the adjustment of measured data to reference conditions. A technical overview of the prediction techniques incorporated into the system is presented. The prediction system has been applied to predict the noise signature of a variety of propeller configurations including the effects of propeller angle of attack. A summary of these validation studies is discussed with emphasis being placed on the wind tunnel and flight test programs sponsored by the Federal Aviation Administration (FAA) for the Piper Cherokee Lance aircraft. A number of modifications and improvements have been made to the system and both DEC VAX and IBM-PC versions of the system have been added to the original CDC NOS version.

  8. A review and update of the NASA aircraft noise prediction program propeller analysis system

    NASA Astrophysics Data System (ADS)

    Golub, Robert A.; Nguyen, L. Cathy

    1989-04-01

    The National Aeronautics and Space Administration (NASA) Aircraft Noise Prediction Program (ANOPP) Propeller Analysis System (PAS) is a set of computational modules for predicting the aerodynamics, performance, and noise of propellers. The ANOPP PAS has the capability to predict noise levels for propeller aircraft certification and produce parametric scaling laws for the adjustment of measured data to reference conditions. A technical overview of the prediction techniques incorporated into the system is presented. The prediction system has been applied to predict the noise signature of a variety of propeller configurations including the effects of propeller angle of attack. A summary of these validation studies is discussed with emphasis being placed on the wind tunnel and flight test programs sponsored by the Federal Aviation Administration (FAA) for the Piper Cherokee Lance aircraft. A number of modifications and improvements have been made to the system and both DEC VAX and IBM-PC versions of the system have been added to the original CDC NOS version.

  9. Control-system techniques for improved departure/spin resistance for fighter aircraft

    NASA Technical Reports Server (NTRS)

    Nguyen, L. T.; Gilbert, W. P.; Ogburn, M. E.

    1980-01-01

    Some fundamental information on control system effects on controllability of highly maneuverable aircraft at high angles of attack are summarized as well as techniques for enhancing fighter aircraft departure/spin resistance using control system design. The discussion includes: (1) a brief review of pertinent high angle of attack phenomena including aerodynamics, inertia coupling, and kinematic coupling; (2) effects of conventional stability augmentation systems at high angles of attack; (3) high angle of attack control system concepts designed to enhance departure/spin resistance; and (4) the outlook for applications of these concepts to future fighters, particularly those designs which incorporate relaxed static stability.

  10. The 400-Hz aircraft power-generation systems: Advancing the baseline

    NASA Astrophysics Data System (ADS)

    Glennon, T.

    1983-06-01

    Today's benchmark system for the Boeing 757/767/A310 airplanes and future trends in hydromechanical aircraft power generating systems are discussed. The 757/767/A310 system represents the commercial state of the art and the direction in which Sundstrand Corp. is headed, particularly in regard to weight reduction. Sundstrand introduced microprocessor control in an in service system in the Boeing 767 and was the first to use databus communications between the controls. Plans to develop this technology are briefly discussed. Alternative ways to produce and use power in aircraft are discussed. The integrated starter drive is discussed.

  11. ANOPP programmer's reference manual for the executive System. [aircraft noise prediction program

    NASA Technical Reports Server (NTRS)

    Gillian, R. E.; Brown, C. G.; Bartlett, R. W.; Baucom, P. H.

    1977-01-01

    Documentation for the Aircraft Noise Prediction Program as of release level 01/00/00 is presented in a manual designed for programmers having a need for understanding the internal design and logical concepts of the executive system software. Emphasis is placed on providing sufficient information to modify the system for enhancements or error correction. The ANOPP executive system includes software related to operating system interface, executive control, and data base management for the Aircraft Noise Prediction Program. It is written in Fortran IV for use on CDC Cyber series of computers.

  12. Pathfinder aircraft flight

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The Pathfinder research aircraft's wing structure is clearly defined as it soars under a clear blue sky during a test flight from Dryden Flight Research Center, Edwards, California, in November of 1996. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus configuration. (See the Pathfinder Plus photos and project description.)

  13. Pathfinder Aircraft in Flight

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The Pathfinder research aircraft's wing structure was clearly defined as it soared under a clear blue sky during a test flight July 27, 1995, from Dryden Flight Research Center, Edwards, California. The center section and outer wing panels of the aircraft had ribs constructed of thin plastic foam, while the ribs in the inner wing panels are fabricated from lightweight composite material. Developed by AeroVironment, Inc., the Pathfinder was one of several unmanned aircraft being evaluated under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) program. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long- duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar- powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus

  14. Pathfinder aircraft in flight

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The Pathfinder research aircraft's wing structure was clearly defined as it soared under a clear blue sky during a test flight July 27, 1995, from Dryden Flight Research Center, Edwards, California. The center section and outer wing panels of the aircraft had ribs constructed of thin plastic foam, while the ribs in the inner wing panels are fabricated from lightweight composite material. Developed by AeroVironment, Inc., the Pathfinder was one of several unmanned aircraft being evaluated under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) program. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus

  15. NASA/Army Rotorcraft Technology. Volume 3: Systems Integration, Research Aircraft, and Industry

    NASA Technical Reports Server (NTRS)

    1988-01-01

    This is part 3 of the conference proceedings on rotorcraft technology. This volume is divided into areas on systems integration, research aircraft, and industry. Representative titles from each area are: system analysis in rotorcraft design, the past decade; rotorcraft flight research with emphasis on rotor systems; and an overview of key technology thrusts at Bell Helicopter Textron.

  16. Status report of a new recovery parachute system for the F111 aircraft crew escape module

    SciTech Connect

    Johnson, D.W.

    1986-01-01

    A new recovery parachute system for the F111 aircraft crew escape module has been designed. Six proof-of-design tests were conducted to determine if it is feasible to meet the requirements for a replacement recovery parachute system. The design of the proposed system is presented and the results of the tests discussed.

  17. Covert penetration systems: future strategic aircraft missions will require a new sensor system approach

    NASA Astrophysics Data System (ADS)

    Fleury, Peter A.

    1987-09-01

    This paper discusses past, present and future strategic aircraft requirements for ingress and egress, then focuses on the tech-nologies of the CO2 Laser Radar and the Automatic Target Recognizer. Present systems currently consist of a mix of various sensors which are not correlated until each is presented to the operator. Additionally, active sensors are highly detectable by threat warning systems, while passive sensors do not provide critical range information. CO2 Laser and AIR tech-nologies will significantly contribute to the resolution of these issues.

  18. Assessment System for Aircraft Noise (ASAN): Development of alpha-test prototype system software

    NASA Astrophysics Data System (ADS)

    Reddingius, Nicholaas H.; Smyth, John S.

    1990-02-01

    The Alpha-Test version of the Assessment System for Aircraft Noise (ASAN) is described. ASAN was developed for the United States Air Force's Noise and Sonic Boom Impact Technology Advanced Development Program Office (NSBIT ADPO). The Purpose of ASAN is to provide Air Force route and environmental planners with a set of tools for preparing the noise portion of environmental impact statements (EIS), environmental assessments (EA), and findings of no significant impact (FONSI). ASAN provides a consistent set of procedures and models which represent the current state-of-the-art in noise engineering practice. A brief overview is given of the technical issues of developing the ASAN system.

  19. Predesign report for the rotor systems research aircraft

    NASA Technical Reports Server (NTRS)

    1972-01-01

    A conceptual predesign of a compound helicopter for conducting rotor research is presented. The aircraft was selected by the Government as the better of two concepts submitted. The helicopter is a three place vehicle in the 24,000 pound gross weight class. It has been determined that the helicopter satisfies the requirements for the rotor research mission. The model has been predesigned sufficiently to allow an assessment of its performance and stability and control characteristics. A brief treatment of these subjects is included.

  20. Human Systems Integration: Unmanned Aircraft Control Station Certification Plan Guidance

    NASA Technical Reports Server (NTRS)

    2005-01-01

    This document provides guidance to the FAA on important human factors considerations that can be used to support the certification of a UAS Aircraft Control Station (ACS). This document provides a synopsis of the human factors analysis, design and test activities to be performed to provide a basis for FAA certification. The data from these analyses, design activities, and tests, along with data from certification/qualification tests of other key components should be used to establish the ACS certification basis. It is expected that this information will be useful to manufacturers in developing the ACS Certification Plan,, and in supporting the design of their ACS.

  1. Advanced fuel system technology for utilizing broadened property aircraft fuels

    NASA Technical Reports Server (NTRS)

    Reck, G. M.

    1980-01-01

    Factors which will determine the future supply and cost of aviation turbine fuels are discussed. The most significant fuel properties of volatility, fluidity, composition, and thermal stability are discussed along with the boiling ranges of gasoline, naphtha jet fuels, kerosene, and diesel oil. Tests were made to simulate the low temperature of an aircraft fuel tank to determine fuel tank temperatures for a 9100-km flight with and without fuel heating; the effect of N content in oil-shale derived fuels on the Jet Fuel Thermal Oxidation Tester breakpoint temperature was measured. Finally, compatibility of non-metallic gaskets, sealants, and coatings with increased aromatic content jet fuels was examined.

  2. An advanced media interface for control of modern transport aircraft navigational systems

    NASA Technical Reports Server (NTRS)

    Jones, D. R.; Parrish, R. V.; Person, L. H., Jr.; Old, J. L.

    1984-01-01

    With the advent of digital avionics, the workload of the pilot in a moderen transport aircraft is increasing significantly. This situation makes it necessary to reduce pilot workload with the aid of new advanced technologies. As part of an effort to improve information management systems, NASA has, therefore, studied an advanced concept for managing the navigational tasks of a modern transport aircraft. This concept is mainly concerned with the simplification of the pilot interface. The advanced navigational system provides a simple method for a pilot to enter new waypoints to change his flight plan because of heavy traffic, adverse weather conditions, or other reasons. The navigational system was implemented and evaluated in a flight simulator representative of a modern transport aircraft. Attention is given to the simulator, flight simulation, multimode devices, and the navigational system.

  3. An AD100 implementation of a real-time STOVL aircraft propulsion system

    NASA Technical Reports Server (NTRS)

    Ouzts, Peter J.; Drummond, Colin K.

    1990-01-01

    A real-time dynamic model of the propulsion system for a Short Take-Off and Vertical Landing (STOVL) aircraft was developed for the AD100 simulation environment. The dynamic model was adapted from a FORTRAN based simulation using the dynamic programming capabilities of the AD100 ADSIM simulation language. The dynamic model includes an aerothermal representation of a turbofan jet engine, actuator and sensor models, and a multivariable control system. The AD100 model was tested for agreement with the FORTRAN model and real-time execution performance. The propulsion system model was also linked to an airframe dynamic model to provide an overall STOVL aircraft simulation for the purposes of integrated flight and propulsion control studies. An evaluation of the AD100 system for use as an aircraft simulation environment is included.

  4. Pose measurement base on machine vision for the aircraft model in wire-driven parallel suspension system

    NASA Astrophysics Data System (ADS)

    Chen, Yi-feng; Wu, Liao-ni; Yue, Sui-lu; Lin, Qi

    2013-03-01

    In wind tunnel tests, the pose of the aircraft model in wire-driven parallel suspension system (WDPSS) is determined by driving several wires. Pose measurement is very important for the study of WDPSS. Using machine vision technology, Monocular Vision Measurement System has been constructed to estimate the pose of the aircraft model by applying a camera calibration, by extracting corresponding control points for the aircraft model, and by applying several homogeneous transformations. This article describes the programs of the measurement system, measurement principle and data processing methods which is based on HALCON to achieve the Solution of the pose of aircraft model. Through experiments, practical feasibility of the system is validated.

  5. Hybrid and Electric Advanced Vehicle Systems Simulation

    NASA Technical Reports Server (NTRS)

    Beach, R. F.; Hammond, R. A.; Mcgehee, R. K.

    1985-01-01

    Predefined components connected to represent wide variety of propulsion systems. Hybrid and Electric Advanced Vehicle System (HEAVY) computer program is flexible tool for evaluating performance and cost of electric and hybrid vehicle propulsion systems. Allows designer to quickly, conveniently, and economically predict performance of proposed drive train.

  6. Characterization of advanced electric propulsion systems

    NASA Technical Reports Server (NTRS)

    Ray, P. K.

    1982-01-01

    Characteristic parameters of several advanced electric propulsion systems are evaluated and compared. The propulsion systems studied are mass driver, rail gun, argon MPD thruster, hydrogen free radical thruster and mercury electron bombardment ion engine. Overall, ion engines have somewhat better characteristics as compared to the other electric propulsion systems.

  7. Computerized systems analysis and optimization of aircraft engine performance, weight, and life cycle costs

    NASA Technical Reports Server (NTRS)

    Fishbach, L. H.

    1980-01-01

    The computational techniques are described which are utilized at Lewis Research Center to determine the optimum propulsion systems for future aircraft applications and to identify system tradeoffs and technology requirements. Cycle performance, and engine weight can be calculated along with costs and installation effects as opposed to fuel consumption alone. Almost any conceivable turbine engine cycle can be studied. These computer codes are: NNEP, WATE, LIFCYC, INSTAL, and POD DRG. Examples are given to illustrate how these computer techniques can be applied to analyze and optimize propulsion system fuel consumption, weight and cost for representative types of aircraft and missions.

  8. Crash response data system for the controlled impact demonstration (CID) of a full scale transport aircraft

    NASA Astrophysics Data System (ADS)

    Calloway, Raymond S.; Knight, Vernie H., Jr.

    NASA Langley's Crash Response Data System (CRDS) which is designed to acquire aircraft structural and anthropomorphic dummy responses during the full-scale transport CID test is described. Included in the discussion are the system design approach, details on key instrumentation subsystems and operations, overall instrumentation crash performance, and data recovery results. Two autonomous high-environment digital flight instrumentation systems, DAS 1 and DAS 2, were employed to obtain research data from various strain gage, accelerometer, and tensiometric sensors installed in the B-720 test aircraft. The CRDS successfully acquired 343 out of 352 measurements of dynamic crash data.

  9. Crash response data system for the controlled impact demonstration (CID) of a full scale transport aircraft

    NASA Technical Reports Server (NTRS)

    Calloway, Raymond S.; Knight, Vernie H., Jr.

    1986-01-01

    NASA Langley's Crash Response Data System (CRDS) which is designed to acquire aircraft structural and anthropomorphic dummy responses during the full-scale transport CID test is described. Included in the discussion are the system design approach, details on key instrumentation subsystems and operations, overall instrumentation crash performance, and data recovery results. Two autonomous high-environment digital flight instrumentation systems, DAS 1 and DAS 2, were employed to obtain research data from various strain gage, accelerometer, and tensiometric sensors installed in the B-720 test aircraft. The CRDS successfully acquired 343 out of 352 measurements of dynamic crash data.

  10. Development of a Corrosion Sensor for AN Aircraft Vehicle Health Monitoring System

    NASA Astrophysics Data System (ADS)

    Scott, D. A.; Price, D. C.; Edwards, G. C.; Batten, A. B.; Kolmeder, J.; Muster, T. H.; Corrigan, P.; Cole, I. S.

    2010-02-01

    A Rayleigh-wave-based sensor has been developed to measure corrosion damage in aircraft. This sensor forms an important part of a corrosion monitoring system being developed for a major aircraft manufacturer. This system measures the corrosion rate at the location of its sensors, and through a model predicts the corrosion rates in nearby places on an aircraft into which no sensors can be placed. In order to calibrate this model, which yields corrosion rates rather than the accumulated effect, an absolute measure of the damage is required. In this paper the development of a surface wave sensor capable of measuring accumulated damage will be described in detail. This sensor allows the system to measure material loss due to corrosion regardless of the possible loss of historical corrosion rate data, and can provide, at any stage, a benchmark for the predictive model that would allow a good estimate of the accumulated corrosion damage in similar locations on an aircraft. This system may obviate the need for costly inspection of difficult-to-access places in aircraft, where presently the only way to check for corrosion is by periodic dismantling and reassembly.

  11. Superconductivity for electric power systems: Program overview

    SciTech Connect

    Not Available

    1995-02-01

    Largely due to government and private industry partnerships, electric power applications based upon high-temperature superconductivity are now being designed and tested only seven years after the discovery of the high-temperature superconductors. These applications offer many benefits to the national electric system including: increased energy efficiency, reduced equipment size, reduced emissions, increased stability/reliability, deferred expansion, and flexible electricity dispatch/load management. All of these benefits have a common outcome: lower electricity costs and improved environmental quality. The U.S. Department of Energy (DOE) sponsors research and development through its Superconductivity Program for Electric Power Systems. This program will help develop the technology needed for U.S. industries to commercialize high-temperature superconductive electric power applications. DOE envisions that by 2010 the U.S. electric power systems equipment industry will regain a major share of the global market by offering superconducting products that outperform the competition.

  12. Onboard Inert Gas Generation System/Onboard Oxygen Gas Generation System (OBIGGS/OBOGS) Study. Part 1; Aircraft System Requirements

    NASA Technical Reports Server (NTRS)

    Reynolds, Thomas L.; Bailey, Delbert B.; Lewinski, Daniel F.; Roseburg, Conrad M.; Palaszewski, Bryan (Technical Monitor)

    2001-01-01

    The purpose of this technology assessment is to define a multiphase research study program investigating Onboard Inert Gas Generation Systems (OBIGGS) and Onboard Oxygen Generation Systems (OBOGS) that would identify current airplane systems design and certification requirements (Subtask 1); explore state-of-the-art technology (Subtask 2); develop systems specifications (Subtask 3); and develop an initial system design (Subtask 4). If feasible, consideration may be given to the development of a prototype laboratory test system that could potentially be used in commercial transport aircraft (Subtask 5). These systems should be capable of providing inert nitrogen gas for improved fire cargo compartment fire suppression and fuel tank inerting and emergency oxygen for crew and passenger use. Subtask I of this research study, presented herein, defines current production aircraft certification requirements and design objectives necessary to meet mandatory FAA certification requirements and Boeing design and performance specifications. These requirements will be utilized for baseline comparisons for subsequent OBIGGS/OBOGS application evaluations and assessments.

  13. Comparison of all-electric secondary power systems for civil subsonic transports

    NASA Technical Reports Server (NTRS)

    Renz, David D.

    1992-01-01

    Three separate studies have shown operational, weight, and cost advantages for commercial subsonic transport aircraft using an all-electric secondary power system. The first study in 1982 showed that all-electric secondary power systems produced the second largest benefit compared to four other technology upgrades. The second study in 1985 showed a 10 percent weight and fuel savings using an all-electric high frequency (20 kHz) secondary power system. The last study in 1991 showed a 2 percent weight savings using today's technology (400 Hz) in an all-electric secondary power system. This paper will compare the 20 kHz and 400 Hz studies, analyze the 2 to 10 percent difference in weight savings and comment on the common benefits of the all-electric secondary power system.

  14. Aircraft exterior scratch measurement system using machine vision

    NASA Astrophysics Data System (ADS)

    Sarr, Dennis P.

    1991-08-01

    In assuring the quality of aircraft skin, it must be free of surface imperfections and structural defects. Manual inspection methods involve mechanical and optical technologies. Machine vision instrumentation can be automated for increasing the inspection rate and repeatability of measurement. As shown by previous industry experience, machine vision instrumentation methods are not calibrated and certified as easily as mechanical devices. The defect must be accurately measured and documented via a printout for engineering evaluation and disposition. In the actual usage of the instrument for inspection, the device must be portable for factory usage, on the flight line, or on an aircraft anywhere in the world. The instrumentation must be inexpensive and operable by a mechanic/technician level of training. The instrument design requirements are extensive, requiring a multidisciplinary approach for the research and development. This paper presents the image analysis results of microscopic structures laser images of scratches on various surfaces. Also discussed are the hardware and algorithms used for the microscopic structures laser images. Dedicated hardware and embedded software for implementing the image acquisition and analysis have been developed. The human interface, human vision is used for determining which image should be processed. Once the image is chosen for analysis, the final answer is a numerical value of the scratch depth. The result is an answer that is reliable and repeatable. The prototype has been built and demonstrated to Boeing Commercial Airplanes Group factory Quality Assurance and flight test management with favorable response.

  15. Nuclear electric propulsion reactor control systems status

    NASA Technical Reports Server (NTRS)

    Ferg, D. A.

    1973-01-01

    The thermionic reactor control system design studies conducted over the past several years for a nuclear electric propulsion system are described and summarized. The relevant reactor control system studies are discussed in qualitative terms, pointing out the significant advantages and disadvantages including the impact that the various control systems would have on the nuclear electric propulsion system design. A recommendation for the reference control system is made, and a program for future work leading to an engineering model is described.

  16. The NASA Langley Research Center's Unmanned Aerial System Surrogate Research Aircraft

    NASA Technical Reports Server (NTRS)

    Howell, Charles T., III; Jessup, Artie; Jones, Frank; Joyce, Claude; Sugden, Paul; Verstynen, Harry; Mielnik, John

    2010-01-01

    Research is needed to determine what procedures, aircraft sensors and other systems will be required to allow Unmanned Aerial Systems (UAS) to safely operate with manned aircraft in the National Airspace System (NAS). The NASA Langley Research Center has transformed a Cirrus Design SR22 general aviation (GA) aircraft into a UAS Surrogate research aircraft to serve as a platform for UAS systems research, development, flight testing and evaluation. The aircraft is manned with a Safety Pilot and systems operator that allows for flight operations almost anywhere in the NAS without the need for a Federal Aviation Administration (FAA) Certificate of Authorization (COA). The UAS Surrogate can be controlled from a modular, transportable ground station like a true UAS. The UAS Surrogate is able to file and fly in the NAS with normal traffic and is a better platform for real world UAS research and development than existing vehicles flying in restricted ranges or other sterilized airspace. The Cirrus Design SR22 aircraft is a small, singleengine, four-place, composite-construction aircraft that NASA Langley acquired to support NASA flight-research programs like the Small Aircraft Transportation System (SATS) Project. Systems were installed to support flight test research and data gathering. These systems include: separate research power; multi-function flat-panel displays; research computers; research air data and inertial state sensors; video recording; data acquisition; data-link; S-band video and data telemetry; Common Airborne Instrumentation System (CAIS); Automatic Dependent Surveillance-Broadcast (ADS-B); instrumented surfaces and controls; and a systems operator work station. The transformation of the SR22 to a UAS Surrogate was accomplished in phases. The first phase was to modify the existing autopilot to accept external commands from a research computer that was connected by redundant data-link radios to a ground control station. An electro-mechanical auto

  17. Fiber Optic Experience with the Smart Actuation System on the F-18 Systems Research Aircraft

    NASA Technical Reports Server (NTRS)

    Zavala, Eddie

    1997-01-01

    High bandwidth, immunity to electromagnetic interference, and potential weight savings have led to the development of fiber optic technology for future aerospace vehicle systems. This technology has been incorporated in a new smart actuator as the primary communication interface. The use of fiber optics simplified system integration and significantly reduced wire count. Flight test results showed that fiber optics could be used in aircraft systems and identified critical areas of development of fly-by-light technology. This paper documents the fiber optic experience gained as a result of this program, and identifies general design considerations that could be used in a variety of specific applications of fiber optic technology. Environmental sensitivities of fiber optic system components that significantly contribute to optical power variation are discussed. Although a calibration procedure successfully minimized the effect of fiber optic sensitivities, more standardized calibration methods are needed to ensure system operation and reliability in future aerospace vehicle systems.

  18. Overview of the Small Aircraft Transportation System Project Four Enabling Operating Capabilities

    NASA Technical Reports Server (NTRS)

    Viken, Sally A.; Brooks, Frederick M.; Johnson, Sally C.

    2005-01-01

    It has become evident that our commercial air transportation system is reaching its peak in terms of capacity, with numerous delays in the system and the demand still steadily increasing. NASA, FAA, and the National Consortium for Aviation Mobility (NCAM) have partnered to aid in increasing the mobility throughout the United States through the Small Aircraft Transportation System (SATS) project. The SATS project has been a five-year effort to provide the technical and economic basis for further national investment and policy decisions to support a small aircraft transportation system. The SATS vision is to enable people and goods to have the convenience of on-demand point-to-point travel, anywhere, anytime for both personal and business travel. This vision can be obtained by expanding near all-weather access to more than 3,400 small community airports that are currently under-utilized throughout the United States. SATS has focused its efforts on four key operating capabilities that have addressed new emerging technologies, procedures, and concepts to pave the way for small aircraft to operate in nearly all weather conditions at virtually any runway in the United States. These four key operating capabilities are: Higher Volume Operations at Non-Towered/Non-Radar Airports, En Route Procedures and Systems for Integrated Fleet Operations, Lower Landing Minimums at Minimally Equipped Landing Facilities, and Increased Single Pilot Performance. The SATS project culminated with the 2005 SATS Public Demonstration in Danville, Virginia on June 5th-7th, by showcasing the accomplishments achieved throughout the project and demonstrating that a small aircraft transportation system could be viable. The technologies, procedures, and concepts were successfully demonstrated to show that they were safe, effective, and affordable for small aircraft in near all weather conditions. The focus of this paper is to provide an overview of the technical and operational feasibility of the

  19. (Wind electric systems). Final report

    SciTech Connect

    Sencenbaugh, J.R.

    1981-06-01

    This report details the results of a demonstration project, the design and testing of a low power, high reliability wind electric system for remote, stand-alone locations. The study consisted of two basic areas. An engineering redesign of a sucessful preproduction prototype to determine best material usage in castings and manufacturing time, in addition to evaluating performance vs cost tradeoffs in design. The second stage of the program covered actual field testing of the redesigned machine in remote areas. After field testing, the machine was to undertake a final redesign to correct any weak areas found during the field evaluation period. Three machines of this design were tested throughout various regions of the United States. These units were located in Nederland, Colorado, Whidbey Island, Washington and Fort Cronkite, San Francisco, CA. The results obtained from prolonged testing were both varied and valuable. A detailed structural analysis was done during the preliminary redesign and final design stages of this program. This report is organized in chronological order.

  20. Evaluation of Laminar Flow Control System Concepts for Subsonic Commercial Transport Aircraft

    NASA Technical Reports Server (NTRS)

    Sturgeon, R. F.

    1980-01-01

    Alternatives in the design of laminar flow control (LFC) subsonic commerical transport aircraft for opeation in the 1980's period were studied. Analyses were conducted to select mission parameters and define optimum aircraft configurational parameters for the selected mission, defined by a passenger payload of 400 and a design range of 12, 038 km (6500 n mi). The baseline aircraft developed for this mission was used as a vehicle for the evaluation and development of alternative LFC system concepts. Alternatices in the areas of aerodynamics, structures and materials, LFC systems, leading-edge region cleaning, and integration of auxiliary systems were studied. Relative to a similarly-optimized advanced technology turbulent transport, the final LFC configuration is approximately equal in DOC but provides descreases of 8.2% in gross weight and 21.7% in fuel consumption.