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Sample records for advanced subsonic civil

  1. Formal representation of the requirements for an Advanced Subsonic Civil Transport (ASCT) flight control system

    NASA Technical Reports Server (NTRS)

    Frincke, Deborah; Wolber, Dave; Fisher, Gene; Cohen, Gerald C.; Mclees, R. E.

    1992-01-01

    A partial requirement specification for an Advanced Subsonic Civil Transport (ASCT) Flight Control System is described. The example was adopted from requirements given in a NASA Contractor report. The language used to describe the requirements, Requirements Specification Language (RSL), is described in a companion document.

  2. An example of requirements for Advanced Subsonic Civil Transport (ASCT) flight control system using structured techniques

    NASA Technical Reports Server (NTRS)

    Mclees, Robert E.; Cohen, Gerald C.

    1991-01-01

    The requirements are presented for an Advanced Subsonic Civil Transport (ASCT) flight control system generated using structured techniques. The requirements definition starts from initially performing a mission analysis to identify the high level control system requirements and functions necessary to satisfy the mission flight. The result of the study is an example set of control system requirements partially represented using a derivative of Yourdon's structured techniques. Also provided is a research focus for studying structured design methodologies and in particular design-for-validation philosophies.

  3. Advanced Subsonic Combustion Rig

    NASA Technical Reports Server (NTRS)

    Lee, Chi-Ming

    1998-01-01

    Researchers from the NASA Lewis Research Center have obtained the first combustion/emissions data under extreme future engine operating conditions. In Lewis' new world-class 60-atm combustor research facility--the Advanced Subsonic Combustion Rig (ASCR)--a flametube was used to conduct combustion experiments in environments as extreme as 900 psia and 3400 F. The greatest challenge for combustion researchers is the uncertainty of the effects of pressure on the formation of nitrogen oxides (NOx). Consequently, U.S. engine manufacturers are using these data to guide their future combustor designs. The flametube's metal housing has an inside diameter of 12 in. and a length of 10.5 in. The flametube can be used with a variety of different flow paths. Each flow path is lined with a high-temperature, castable refractory material (alumina) to minimize heat loss. Upstream of the flametube is the injector section, which has an inside diameter of 13 in. and a length of 0.5-in. It was designed to provide for quick changeovers. This flametube is being used to provide all U.S. engine manufacturers early assessments of advanced combustion concepts at full power conditions prior to engine production. To date, seven concepts from engine manufacturers have been evaluated and improved. This collaborated development can potentially give U.S. engine manufacturers the competitive advantage of being first in the market with advanced low-emission technologies.

  4. 14 CFR 91.853 - Final compliance: Civil subsonic airplanes.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Final compliance: Civil subsonic airplanes... Noise Limits § 91.853 Final compliance: Civil subsonic airplanes. Except as provided in § 91.873, after... airplane subject to § 91.801(c) of this subpart, unless that airplane has been shown to comply with Stage...

  5. 14 CFR 91.853 - Final compliance: Civil subsonic airplanes.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Final compliance: Civil subsonic airplanes... Noise Limits § 91.853 Final compliance: Civil subsonic airplanes. Except as provided in § 91.873, after... airplane subject to § 91.801(c) of this subpart, unless that airplane has been shown to comply with Stage...

  6. Advanced Subsonic Combustion Rig Developed

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The Advanced Subsonic Combustion Rig (ASCR), a unique, state-of-the-art facility for conducting combustion research, is located at the NASA Lewis Research Center in Cleveland, Ohio. The ASCR, which was nearing completion at the close of 1995, will be capable of simulating the very high pressure and high temperature conditions that are expected to exist in future, advanced subsonic gas turbine (jet) engines. Future environmental regulations will require much cleaner burning (more environmentally friendly) aircraft engines. The ASCR is critical to the development of these cleaner engines. It will allow NASA and U.S. aircraft engine industry researchers to identify and test promising clean-burning gas turbine engine combustion concepts under the pressure and temperature conditions that are expected for those future engines. Combustion processes will be investigated for a variety of next-generation aircraft engine sizes, including engines for large, long-range aircraft (with typical trip lengths of about 3000 mi) and for regional aircraft (with typical trip lengths of about 400 mi). The ASCR design was conceived and initiated in 1993, and fabrication and construction of the rig, including the buildup of an advanced control room, took place throughout 1994 and 1995. In early 1996, the ASCR will be operational for obtaining research data. The ASCR is an intricate part of the NASA Advanced Subsonic Technology Propulsion Program, which is aimed at developing technologies critical to the next generation of gas turbine engines. This effort is in collaboration with the U.S. aircraft gas turbine engine industry. A goal of the Advanced Subsonic Technology Propulsion Program is to develop combustion concepts and technologies that will result in gas turbine engines that produce 50 percent less nitrous oxide (NO_x) pollutants than current engines do. This facility is unique in its capability to simulate advanced subsonic engine pressure, temperature, and air flow rate conditions

  7. Propulsion technology for an advanced subsonic transport

    NASA Technical Reports Server (NTRS)

    Beheim, M. A.; Antl, R. J.; Povolny, J. H.

    1972-01-01

    Engine design studies for future subsonic commercial transport aircraft were conducted in parallel with airframe studies. These studies surveyed a broad distribution of design variables, including aircraft configuration, payload, range, and speed, with particular emphasis on reducing noise and exhaust emissions without severe economic and performance penalties. The results indicated that an engine for an advanced transport would be similar to the currently emerging turbofan engines. Application of current technology in the areas of noise suppression and combustors imposed severe performance and economic penalties.

  8. 14 CFR 91.881 - Final compliance: Civil subsonic jet airplanes weighing 75,000 pounds or less.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Final compliance: Civil subsonic jet... OPERATING AND FLIGHT RULES Operating Noise Limits § 91.881 Final compliance: Civil subsonic jet airplanes... operate to or from an airport in the contiguous United States a civil subsonic jet airplane subject...

  9. Advanced Subsonic Airplane Design and Economic Studies

    NASA Technical Reports Server (NTRS)

    Liebeck, Robert H.; Andrastek, Donald A.; Chau, Johnny; Girvin, Raquel; Lyon, Roger; Rawdon, Blaine K.; Scott, Paul W.; Wright, Robert A.

    1995-01-01

    A study was made to examine the effect of advanced technology engines on the performance of subsonic airplanes and provide a vision of the potential which these advanced engines offered. The year 2005 was selected as the entry-into-service (EIS) date for engine/airframe combination. A set of four airplane classes (passenger and design range combinations) that were envisioned to span the needs for the 2005 EIS period were defined. The airframes for all classes were designed and sized using 2005 EIS advanced technology. Two airplanes were designed and sized for each class: one using current technology (1995) engines to provide a baseline, and one using advanced technology (2005) engines. The resulting engine/airframe combinations were compared and evaluated on the basis on sensitivity to basic engine performance parameters (e.g. SFC and engine weight) as well as DOC+I. The advanced technology engines provided significant reductions in fuel burn, weight, and wing area. Average values were as follows: reduction in fuel burn = 18%, reduction in wing area = 7%, and reduction in TOGW = 9%. Average DOC+I reduction was 3.5% using the pricing model based on payload-range index and 5% using the pricing model based on airframe weight. Noise and emissions were not considered.

  10. Manifestations of advanced civilizations

    NASA Astrophysics Data System (ADS)

    Bracewell, R. N.

    A list of possible modes of detecting advanced civilizations elsewhere in the universe is provided, including EM Alfven, and gravity waves, matter transfer, and exotica such as tachyons, black hole tunneling, and telepathy. Further study is indicated for low frequency radio wave propagation, which may travel along magnetic fields to reach the earth while laser beams are not favored because of the power needed for transmitting quanta instead of waves. IR, X ray, and UV astronomy are noted to be suitable for detecting signals in those ranges, while Alfven wave communication will be best observed by probes outside the orbit of Jupiter, where local anomalies have less effect. Particle propagation communication is viewed as unlikely, except as a trace of an extinct civilization, but panspermia, which involves interstellar spreading of seeds and/or spores, receives serious attention, as does laser probe or pellet propulsion.

  11. Advanced surface paneling method for subsonic and supersonic flow

    NASA Technical Reports Server (NTRS)

    Erickson, L. L.; Johnson, F. T.; Ehlers, F. E.

    1976-01-01

    Numerical results illustrating the capabilities of an advanced aerodynamic surface paneling method are presented. The method is applicable to both subsonic and supersonic flow, as represented by linearized potential flow theory. The method is based on linearly varying sources and quadratically varying doublets which are distributed over flat or curved panels. These panels are applied to the true surface geometry of arbitrarily shaped three dimensional aerodynamic configurations.

  12. 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.

  13. User's manual: Subsonic/supersonic advanced panel pilot code

    NASA Technical Reports Server (NTRS)

    Moran, J.; Tinoco, E. N.; Johnson, F. T.

    1978-01-01

    Sufficient instructions for running the subsonic/supersonic advanced panel pilot code were developed. This software was developed as a vehicle for numerical experimentation and it should not be construed to represent a finished production program. The pilot code is based on a higher order panel method using linearly varying source and quadratically varying doublet distributions for computing both linearized supersonic and subsonic flow over arbitrary wings and bodies. This user's manual contains complete input and output descriptions. A brief description of the method is given as well as practical instructions for proper configurations modeling. Computed results are also included to demonstrate some of the capabilities of the pilot code. The computer program is written in FORTRAN IV for the SCOPE 3.4.4 operations system of the Ames CDC 7600 computer. The program uses overlay structure and thirteen disk files, and it requires approximately 132000 (Octal) central memory words.

  14. Advanced Low Emissions Subsonic Combustor Study

    NASA Technical Reports Server (NTRS)

    Smith, Reid

    1998-01-01

    Recent advances in commercial and military aircraft gas turbines have yielded significant improvements in fuel efficiency and thrust-to-weight ratio, due in large part to increased combustor operating pressures and temperatures. However, the higher operating conditions have increased the emission of oxides of nitrogen (NOx), which is a pollutant with adverse impact on the atmosphere and environment. Since commercial and military aircraft are the only important direct source of NOx emissions at high altitudes, there is a growing consensus that considerably more stringent limits on NOx emissions will be required in the future for all aircraft. In fact, the regulatory communities have recently agreed to reduce NOx limits by 20 percent from current requirements effective in 1996. Further reductions at low altitude, together with introduction of limits on NOx at altitude, are virtual certainties. In addition, the U.S. Government recently conducted hearings on the introduction of federal fees on the local emission of pollutants from all sources, including aircraft. While no action was taken regarding aircraft in this instance, the threat of future action clearly remains. In these times of intense and growing international competition, the U.S. le-ad in aerospace can only be maintained through a clear technological dominance that leads to a product line of maximum value to the global airline customer. Development of a very low NOx combustor will be essential to meet the future needs of both the commercial and military transport markets, if additional economic burdens and/or operational restrictions are to be avoided. In this report, Pratt & Whitney (P&W) presents the study results with the following specific objectives: Development of low-emissions combustor technologies for advances engines that will enter into service circa 2005, while producing a goal of 70 percent lower NOx emissions, compared to 1996 regulatory levels. Identification of solution approaches to

  15. Analysis of an advanced technology subsonic turbofan incorporating revolutionary materials

    NASA Technical Reports Server (NTRS)

    Knip, Gerald, Jr.

    1987-01-01

    Successful implementation of revolutionary composite materials in an advanced turbofan offers the possibility of further improvements in engine performance and thrust-to-weight ratio relative to current metallic materials. The present analysis determines the approximate engine cycle and configuration for an early 21st century subsonic turbofan incorporating all composite materials. The advanced engine is evaluated relative to a current technology baseline engine in terms of its potential fuel savings for an intercontinental quadjet having a design range of 5500 nmi and a payload of 500 passengers. The resultant near optimum, uncooled, two-spool, advanced engine has an overall pressure ratio of 87, a bypass ratio of 18, a geared fan, and a turbine rotor inlet temperature of 3085 R. Improvements result in a 33-percent fuel saving for the specified misssion. Various advanced composite materials are used throughout the engine. For example, advanced polymer composite materials are used for the fan and the low pressure compressor (LPC).

  16. NASA Noise Reduction Program for Advanced Subsonic Transports

    NASA Technical Reports Server (NTRS)

    Stephens, David G.; Cazier, F. W., Jr.

    1995-01-01

    Aircraft noise is an important byproduct of the world's air transportation system. Because of growing public interest and sensitivity to noise, noise reduction technology is becoming increasingly important to the unconstrained growth and utilization of the air transportation system. Unless noise technology keeps pace with public demands, noise restrictions at the international, national and/or local levels may unduly constrain the growth and capacity of the system to serve the public. In recognition of the importance of noise technology to the future of air transportation as well as the viability and competitiveness of the aircraft that operate within the system, NASA, the FAA and the industry have developed noise reduction technology programs having application to virtually all classes of subsonic and supersonic aircraft envisioned to operate far into the 21st century. The purpose of this paper is to describe the scope and focus of the Advanced Subsonic Technology Noise Reduction program with emphasis on the advanced technologies that form the foundation of the program.

  17. Subsonic Aerodynamic Assessment of Vortex Flow Management Devices on a High-Speed Civil Transport Configuration

    NASA Technical Reports Server (NTRS)

    Campbell, Bryan A.; Applin, Zachary T.; Kemmerly, Guy T.

    1999-01-01

    An experimental investigation of the effects of leading-edge vortex management devices on the subsonic performance of a high-speed civil transport (HSCT) configuration was conducted in the Langley 14- by 22-Foot Subsonic Tunnel. Data were obtained over a Mach number range of 0.14 to 0.27, with corresponding chord Reynolds numbers of 3.08 x 10 (sup 6) to 5.47 x 10 (sup 6). The test model was designed for a cruise Mach number of 2.7. During the subsonic high-lift phase of flight, vortical flow dominates the upper surface flow structure, and during vortex breakdown, this flow causes adverse pitch-up and a reduction of usable lift. The experimental results showed that the beneficial effects of small leading-edge vortex management devices located near the model reference center were insufficient to substantially affect the resulting aerodynamic forces and moments. However, devices located at or near the wiring apex region demonstrated potential for pitch control with little effect on overall lift.

  18. Evaluation of the Advanced Subsonic Technology Program Noise Reduction Benefits

    NASA Technical Reports Server (NTRS)

    Golub, Robert A.; Rawls, John W., Jr.; Russell, James W.

    2005-01-01

    This report presents a detailed evaluation of the aircraft noise reduction technology concepts developed during the course of the NASA/FAA Advanced Subsonic Technology (AST) Noise Reduction Program. In 1992, NASA and the FAA initiated a cosponsored, multi-year program with the U.S. aircraft industry focused on achieving significant advances in aircraft noise reduction. The program achieved success through a systematic development and validation of noise reduction technology. Using the NASA Aircraft Noise Prediction Program, the noise reduction benefit of the technologies that reached a NASA technology readiness level of 5 or 6 were applied to each of four classes of aircraft which included a large four engine aircraft, a large twin engine aircraft, a small twin engine aircraft and a business jet. Total aircraft noise reductions resulting from the implementation of the appropriate technologies for each class of aircraft are presented and compared to the AST program goals.

  19. Advanced Configurations for Very Large Subsonic Transport Airplanes

    NASA Technical Reports Server (NTRS)

    McMasters, John H.; Paisley, David J.; Hubert, Richard J.; Kroo, Ilan; Bofah, Kwasi K.; Sullivan, John P.; Drela, Mark

    1996-01-01

    Recent aerospace industry interest in developing a subsonic commercial transport airplane with 50 percent greater passenger capacity than the largest existing aircraft in this category (the Boeing 747-400 with approximately 400-450 seats) has generated a range of proposals based largely on the configuration paradigm established nearly 50 years ago with the Boeing B-47 bomber. While this basic configuration paradigm has come to dominate subsonic commercial airplane development since the advent of the Boeing 707/Douglas DC-8 in the mid-1950's, its extrapolation to the size required to carry more than 600-700 passengers raises several questions. To explore these and a number of related issues, a team of Boeing, university, and NASA engineers was formed under the auspices of the NASA Advanced Concepts Program. The results of a Research Analysis focused on a large, unconventional transport airplane configuration for which Boeing has applied for a patent are the subject of this report. It should be noted here that this study has been conducted independently of the Boeing New Large Airplane (NLA) program, and with the exception of some generic analysis tools which may be common to this effort and the NLA (as will be described later), no explicit Boeing NLA data other than that published in the open literature has been used in the conduct of the study reported here.

  20. Atmospheric Effects of Subsonic Aircraft: Interim Assessment Report of the Advanced Subsonic Technology Program

    NASA Technical Reports Server (NTRS)

    Friedl, Randall R. (Editor)

    1997-01-01

    This first interim assessment of the subsonic assessment (SASS) project attempts to summarize concisely the status of our knowledge concerning the impacts of present and future subsonic aircraft fleets. It also highlights the major areas of scientific uncertainty, through review of existing data bases and model-based sensitivity studies. In view of the need for substantial improvements in both model formulations and experimental databases, this interim assessment cannot provide confident numerical predictions of aviation impacts. However, a number of quantitative estimates are presented, which provide some guidance to policy makers.

  1. Analysis of an advanced ducted propeller subsonic inlet

    NASA Technical Reports Server (NTRS)

    Iek, Chanthy; Boldman, Donald R.; Ibrahim, Mounir

    1992-01-01

    A time marching Navier-Stokes code called PARC (PARC2D for 2-D/axisymmetric and PARC3D for 3-D flow simulations) was validated for an advanced ducted propeller (ADP) subsonic inlet. The code validation for an advanced ducted propeller (ADP) subsonic inlet. The code validation was implemented for a non-separated flow condition associated with the inlet operating at angles-of-attack of 0 and 25 degrees. The inlet test data were obtained in the 9 x 15 ft Low Speed Wind Tunnel at NASA Lewis Research Center as part of a cooperative study with Pratt and Whitney. The experimental study focused on the ADP inlet performance for take-off and approach conditions. The inlet was tested at a free stream Mach number of 0.2, at angles-of-attack between O and 35 degrees, and at a maximum propeller speed of 12,000 RPM which induced a corrected air flow rate of about 46 lb/sec based on standard day conditions. The computational grid and flow boundary conditions (BC) were based on the actual inlet geometry and the funnel flow conditions. At the propeller face, two types of BC's were applied: a mass flow BC and a fixed flow properties BC. The fixed flow properties BC was based on a combination of data obtained from the experiment and calculations using a potential flow code. Comparison of the computational results with the test data indicates that the PARC code with the propeller face fixed flow properties BC provided a better prediction of the inlet surface static pressures than the predictions when the mass flow BC was used. For an angle-of-attack of 0 degrees, the PARC2D code with the propeller face mass flow BC provided a good prediction of inlet static pressures except in the region of high pressure gradient. With the propeller face fixed flow properties BC, the PARC2D code provided a good prediction of the inlet static pressures. For an angle-of-attack of 25 degrees with the mass flow BC, the PARC3D code predicted statis pressures which deviated significantly from the test data

  2. Expanding Advanced Civilizations in the Universe

    NASA Astrophysics Data System (ADS)

    Gros, C.

    The 1950 lunch-table remark by Enrico Fermi `Where is everybody' has started intensive scientific and philosophical discussions about what we call nowadays the `Fermi paradox': If there had been ever a single advanced civilization in the cosmological history of our galaxy, dedicated to expansion, it would have had plenty of time to colonize the entire galaxy via exponential growth. No evidence of present or past alien visits to earth are known to us, leading to the standard conclusion that no advanced expanding civilization has ever existed in the milky-way. This conclusion rest fundamentally on the ad-hoc assumption, that any alien civilizations dedicated to expansion at one time would remain dedicated to expansions forever. Considering our limited knowledge about alien civilizations we need however to relax this basic assumption. Here we show that a substantial and stable population of expanding advanced civilization might consequently exist in our galaxy.

  3. The Civil Rights Act of 1990: Advancing Civil Rights?

    DTIC Science & Technology

    1990-01-01

    Executive Officer, Civilian Institution Programs DTIC S ELECTE OCT24 19901 76 UNCLASSIFIED 4 THE CIVIL FIGHTI’S ACI’ OCF 1990 ADVA~NCING CIVIL RIGHTS...where it recruits, where it advertises, when it 42 irntten statement of Lawrence Z. Lorber before the Senate Committee on Labor and Human Resources...S. at .TS. Wr:::en statement :f "haries Fr:ei ’efore ti. Senate Committee on Labor and Human Resources, ,4. at p,3. 22 Any reflection on how the

  4. Advanced subsonic Technology Noise Reduction Element Separate Flow Nozzle Tests for Engine Noise Reduction Sub-Element

    NASA Technical Reports Server (NTRS)

    Saiyed, Naseem H.

    2000-01-01

    Contents of this presentation include: Advanced Subsonic Technology (AST) goals and general information; Nozzle nomenclature; Nozzle schematics; Photograph of all baselines; Configurations tests and types of data acquired; and Engine cycle and plug geometry impact on EPNL.

  5. Power-by-Wire Development and Demonstration for Subsonic Civil Transport

    NASA Technical Reports Server (NTRS)

    1996-01-01

    During the last decade, three significant studies by the Lockheed Martin Corporation, the NASA Lewis Research Center, and McDonnell Douglas Corporation have clearly shown operational, weight, and cost advantages for commercial subsonic transport aircraft that use all-electric or more-electric technologies in the secondary electric power systems. Even though these studies were completed on different aircraft, used different criteria, and applied a variety of technologies, all three have shown large benefits to the aircraft industry and to the nation's competitive position. The Power-by-Wire (PBW) program is part of the highly reliable Fly-By-Light/Power-By-Wire (FBL/PBW) Technology Program, whose goal is to develop the technology base for confident application of integrated FBL/PBW systems for transport aircraft. This program is part of the NASA aeronautics strategic thrust in subsonic aircraft/national airspace (Thrust 1) to "develop selected high-leverage technologies and explore new means to ensure the competitiveness of U.S. subsonic aircraft and to enhance the safety and productivity of the national aviation system" (The Aeronautics Strategic Plan). Specifically, this program is an initiative under Thrust 1, Key Objective 2, to "develop, in cooperation with U.S. industry, selected high-payoff technologies that can enable significant improvements in aircraft efficiency and cost."

  6. Subsonic Investigation of a Leading-Edge Boundary Layer Control Suction System on a High-Speed Civil Transport Configuration

    NASA Technical Reports Server (NTRS)

    Campbell, Bryan A.; Applin, Zachary T.; Kemmerly, Guy T.; Coe, Paul L., Jr.; Owens, D. Bruce; Gile, Brenda E.; Parikh, Pradip G.; Smith, Don

    1999-01-01

    A wind tunnel investigation of a leading edge boundary layer control system was conducted on a High Speed Civil Transport (HSCT) configuration in the Langley 14- by 22-Foot Subsonic Tunnel. Data were obtained over a Mach number range of 0.08 to 0.27, with corresponding chord Reynolds numbers of 1.79 x 10(exp 6) to 5.76 x 10(exp 6). Variations in the amount of suction, as well as the size and location of the suction area, were tested with outboard leading edge flaps deflected 0 and 30 deg and trailing-edge flaps deflected 0 and 20 deg. The longitudinal and lateral aerodynamic data are presented without analysis. A complete tabulated data listing is also presented herein.

  7. Energy and Economic Trade Offs for Advanced Technology Subsonic Aircraft

    NASA Technical Reports Server (NTRS)

    Maddalon, D. V.; Wagner, R. D.

    1976-01-01

    Changes in future aircraft technology which conserve energy are studied, along with the effect of these changes on economic performance. Among the new technologies considered are laminar-flow control, composite materials with and without laminar-flow control, and advanced airfoils. Aircraft design features studied include high-aspect-ratio wings, thickness ratio, and range. Engine technology is held constant at the JT9D level. It is concluded that wing aspect ratios of future aircraft are likely to significantly increase as a result of new technology and the push of higher fuel prices. Composite materials may raise aspect radio to about 11 to 12 and practical laminar flow-control systems may further increase aspect ratio to 14 or more. Advanced technology provides significant reductions in aircraft take-off gross weight, energy consumption, and direct operating cost.

  8. Advanced subsonic long-haul transport terminal area compatibility study. Volume 1: Compatibility assessment

    NASA Technical Reports Server (NTRS)

    1974-01-01

    An analysis was made to identify airplane research and technology necessary to ensure advanced transport aircraft the capability of accommodating forecast traffic without adverse impact on airport communities. Projections were made of the delay, noise, and emissions impact of future aircraft fleets on typical large urban airport. Design requirements, based on these projections, were developed for an advanced technology, long-haul, subsonic transport. A baseline aircraft was modified to fulfill the design requirements for terminal area compatibility. Technical and economic comparisons were made between these and other aircraft configured to support the study.

  9. Energy and economic trade offs for advanced technology subsonic aircraft

    NASA Technical Reports Server (NTRS)

    Maddalon, D. V.; Wagner, R. D.

    1976-01-01

    Changes in future aircraft technology which conserve energy are studied, along with the effect of these changes on economic performance. Among the new technologies considered are laminar-flow control, composite materials with and without laminar-flow control, and advanced airfoils. Aircraft design features studied include high-aspect-ratio wings, thickness ratio, and range. Engine technology is held constant at the JT9D level. It is concluded that wing aspect ratios of future aircraft are likely to significantly increase as a result of new technology and the push of higher fuel prices. Whereas current airplanes have been designed for AR = 7, supercritical technology and much higher fuel prices will drive aspect ratio to the AR = 9-10 range. Composite materials may raise aspect ratio to about 11-12 and practical laminar flow-control systems may further increase aspect ratio to 14 or more. Advanced technology provides significant reductions in aircraft take-off gross weight, energy consumption, and direct operating cost.

  10. Engine Seal Technology Requirements to Meet NASA's Advanced Subsonic Technology Program Goals

    NASA Technical Reports Server (NTRS)

    Steinetz, Bruce M.; Hendricks, Robert C.

    1994-01-01

    Cycle studies have shown the benefits of increasing engine pressure ratios and cycle temperatures to decrease engine weight and improve performance of commercial turbine engines. NASA is working with industry to define technology requirements of advanced engines and engine technology to meet the goals of NASA's Advanced Subsonic Technology Initiative. As engine operating conditions become more severe and customers demand lower operating costs, NASA and engine manufacturers are investigating methods of improving engine efficiency and reducing operating costs. A number of new technologies are being examined that will allow next generation engines to operate at higher pressures and temperatures. Improving seal performance - reducing leakage and increasing service life while operating under more demanding conditions - will play an important role in meeting overall program goals of reducing specific fuel consumption and ultimately reducing direct operating costs. This paper provides an overview of the Advanced Subsonic Technology program goals, discusses the motivation for advanced seal development, and highlights seal technology requirements to meet future engine performance goals.

  11. Subsonic Ultra Green Aircraft Research Phase II: N+4 Advanced Concept Development

    NASA Technical Reports Server (NTRS)

    Bradley, Marty K.; Droney, Christopher K.

    2012-01-01

    This final report documents the work of the Boeing Subsonic Ultra Green Aircraft Research (SUGAR) team on Task 1 of the Phase II effort. The team consisted of Boeing Research and Technology, Boeing Commercial Airplanes, General Electric, and Georgia Tech. Using a quantitative workshop process, the following technologies, appropriate to aircraft operational in the N+4 2040 timeframe, were identified: Liquefied Natural Gas (LNG), Hydrogen, fuel cell hybrids, battery electric hybrids, Low Energy Nuclear (LENR), boundary layer ingestion propulsion (BLI), unducted fans and advanced propellers, and combinations. Technology development plans were developed.

  12. An advanced panel method for analysis of arbitrary configurations in unsteady subsonic flow

    NASA Technical Reports Server (NTRS)

    Dusto, A. R.; Epton, M. A.

    1980-01-01

    An advanced method is presented for solving the linear integral equations for subsonic unsteady flow in three dimensions. The method is applicable to flows about arbitrary, nonplanar boundary surfaces undergoing small amplitude harmonic oscillations about their steady mean locations. The problem is formulated with a wake model wherein unsteady vorticity can be convected by the steady mean component of flow. The geometric location of the unsteady source and doublet distributions can be located on the actual surfaces of thick bodies in their steady mean locations. The method is an outgrowth of a recently developed steady flow panel method and employs the linear source and quadratic doublet splines of that method.

  13. Analysis of a high speed civil transport configuration at subsonic flow conditions using a Navier-Stokes solver

    NASA Technical Reports Server (NTRS)

    Lessard, Victor R.

    1993-01-01

    Computations of three dimensional vortical flows over a generic High Speed Civil Transport (HSCT) configuration with an aspect ratio of 3.04 are performed using a thin-layer Navier-Stokes solver. The HSCT cruise configuration is modeled without leading or trailing edge flap deflections and without engine nacelles. The flow conditions, which correspond to tests done in the NASA Langley 8-Foot Transonic Pressure Tunnel (TPT), are a subsonic Mach number of 0.3 and Reynolds number of 4.4 million for a range-of-attack (-.23 deg to 17.78 deg). The effects of the farfield boundary location with respect to the body are investigated. The boundary layer is assumed turbulent and simulated using an algebraic turbulence model. The key features of the vortices and their interactions are captured. Grid distribution in the vortex regions is critical for predicting the correct induced lift. Computed forces and surface pressures compare reasonably well with the experimental TPT data.

  14. The development and evaluation of advanced technology laminar-flow-control subsonic transport aircraft

    NASA Technical Reports Server (NTRS)

    Sturgeon, R. F.

    1978-01-01

    A study was conducted to evaluate the technical and economic feasibility of applying laminar flow control (LFC) to the wings and empennage of long-range subsonic transport aircraft for initial operation in 1985. For a design mission range of 5500 n mi, advanced technology LFC and turbulent-flow aircraft were developed for a 200-passenger payload, and compared on the basis of production costs, direct operating costs, and fuel efficiency. Parametric analyses were conducted to establish optimum geometry, advanced system concepts were evaluated, and configuration variations maximizing the effectiveness of LFC were developed. The final comparisons include consideation of maintenance costs and procedures, manufacturing costs and procedures, and operational considerations peculiar to LFC aircraft.

  15. Advanced subsonic transport approach noise: The relative contribution of airframe noise

    NASA Technical Reports Server (NTRS)

    Willshire, William L., Jr.; Garber, Donald P.

    1992-01-01

    With current engine technology, airframe noise is a contributing source for large commercial aircraft on approach, but not the major contributor. With the promise of much quieter jet engines with the planned new generation of high-by-pass turbofan engines, airframe noise has become a topic of interest in the advanced subsonic transport research program. The objective of this paper is to assess the contribution of airframe noise relative to the other aircraft noise sources on approach. The assessment will be made for a current technology large commercial transport aircraft and for an envisioned advanced technology aircraft. NASA's Aircraft Noise Prediction Program (ANOPP) will be used to make total aircraft noise predictions for these two aircraft types. Predicted noise levels and areas of noise contours will be used to determine the relative importance of the contributing approach noise sources. The actual set-up decks used to make the ANOPP runs for the two aircraft types are included in appendixes.

  16. A Full Navier-Stokes Analysis of Subsonic Diffuser of a Bifurcated 70/30 Supersonic Inlet for High Speed Civil Transport Application

    NASA Technical Reports Server (NTRS)

    Kapoor, Kamlesh; Anderson, Bernhard H.; Shaw, Robert J.

    1994-01-01

    A full Navier-Stokes analysis was performed to evaluate the performance of the subsonic diffuser of a NASA Lewis Research Center 70/30 mixed-compression bifurcated supersonic inlet for high speed civil transport application. The PARC3D code was used in the present study. The computations were also performed when approximately 2.5 percent of the engine mass flow was allowed to bypass through the engine bypass doors. The computational results were compared with the available experimental data which consisted of detailed Mach number and total pressure distribution along the entire length of the subsonic diffuser. The total pressure recovery, flow distortion, and crossflow velocity at the engine face were also calculated. The computed surface ramp and cowl pressure distributions were compared with experiments. Overall, the computational results compared well with experimental data. The present CFD analysis demonstrated that the bypass flow improves the total pressure recovery and lessens flow distortions at the engine face.

  17. Propulsion system studies for an advanced high subsonic, long range jet commercial transport aircraft

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Propulsion system characteristics for a long range, high subsonic (Mach 0.90 - 0.98), jet commercial transport aircraft are studied to identify the most desirable cycle and engine configuration and to assess the payoff of advanced engine technologies applicable to the time frame of the late 1970s to the mid 1980s. An engine parametric study phase examines major cycle trends on the basis of aircraft economics. This is followed by the preliminary design of two advanced mixed exhaust turbofan engines pointed at two different technology levels (1970 and 1985 commercial certification for engines No. 1 and No. 2, respectively). The economic penalties of environmental constraints - noise and exhaust emissions - are assessed. The highest specific thrust engine (lowest bypass ratio for a given core technology) achievable with a single-stage fan yields the best economics for a Mach 0.95 - 0.98 aircraft and can meet the noise objectives specified, but with significant economic penalties. Advanced technologies which would allow high temperature and cycle pressure ratios to be used effectively are shown to provide significant improvement in mission performance which can partially offset the economic penalties incurred to meet lower noise goals. Advanced technology needs are identified; and, in particular, the initiation of an integrated fan and inlet aero/acoustic program is recommended.

  18. Advanced Civil Transport Simulator Cockpit View

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The Advanced Civil Transport Simulator (ACTS) is a futuristic aircraft cockpit simulator designed to provide full-mission capabilities for researching issues that will affect future transport aircraft flight stations and crews. The objective is to heighten the pilots situation awareness through improved information availability and ease of interpretation in order to reduce the possibility of misinterpreted data. The simulators five 13-inch Cathode Ray Tubes are designed to display flight information in a logical easy-to-see format. Two color flat panel Control Display Units with touch sensitive screens provide monitoring and modification of aircraft parameters, flight plans, flight computers, and aircraft position. Three collimated visual display units have been installed to provide out-the-window scenes via the Computer Generated Image system. The major research objectives are to examine needs for transfer of information to and from the flight crew; study the use of advanced controls and displays for all-weather flying; explore ideas for using computers to help the crew in decision making; study visual scanning and reach behavior under different conditions with various levels of automation and flight deck-arrangements.

  19. The influence of subsonic mission segments on the use of variable-sweep wings for high speed civil transport configurations

    NASA Technical Reports Server (NTRS)

    Martin, Glenn L.; Beissner, Fred L., Jr.; Domack, Christopher S.; Shields, E. William

    1988-01-01

    A Mach-3.0, 250-passenger, 6500-n. mi. range SST configuration's alternative use of fixed-planform or variable-sweep wings is presently evaluated, with a view to effects on aerodynamics, mission performance, and sizing. After preliminary design, the fixed and variable-wing configurations were resized to perform missions incorporating subsonic cruise segments of as much as 4000 n. mi.; the effect of subsonic segment length on design gross weight and block time was then ascertained. Due to the reduced supersonic efficiency of the variable-sweep aircraft, over one-half of the 6500-n. mi. mission would have to be flown subsonically for its sizing to reach a lower ramp weight than that of its fixed-geometry counterpart.

  20. Integrated Application of Active Controls (IAAC) technology to an advanced subsonic transport project: Program review

    NASA Technical Reports Server (NTRS)

    1986-01-01

    This report summarizes the Integrated Application of Active Controls (IAAC) Technology to an Advanced Subsonic Transport Project, established as one element of the NASA/Boeing Energy Efficient Transport Technology Program. The performance assessment showed that incorporating ACT into an airplane designed to fly approximately 200 passengers approximately 2,000 nmi could yield block fuel savings from 6 to 10 percent at the design range. The principal risks associated with incorporating these active control functions into a commercial airplane are those involved with the ACT system implementation. The Test and Evaluation phase of the IAAC Project focused on the design, fabrication, and test of a system that implemented pitch axis fly-by-wire, pitch axis augmentation, and wing load alleviation. The system was built to be flight worthy, and was planned to be experimentally flown on the 757. The system was installed in the Boeing Digital Avionics Flight Controls Laboratory (DAFCL), where open loop hardware and software tests, and a brief examination of a direct drive valve (DDV) actuation concept were accomplished. The IAAC Project has shown that ACT can be beneficially incorporated into a commercial transport airplane. Based on the results achieved during the testing phase, there appears to be no fundamental reason(s) that would preclude the commercial application of ACT, assuming an appropriate development effort is included.

  1. Integrated Application of Active Controls (IAAC) technology to an advanced subsonic transport project: Current and advanced act control system definition study. Volume 2: Appendices

    NASA Technical Reports Server (NTRS)

    Hanks, G. W.; Shomber, H. A.; Dethman, H. A.; Gratzer, L. B.; Maeshiro, A.; Gangsaas, D.; Blight, J. D.; Buchan, S. M.; Crumb, C. B.; Dorwart, R. J.

    1981-01-01

    The current status of the Active Controls Technology (ACT) for the advanced subsonic transport project is investigated through analysis of the systems technical data. Control systems technologies under examination include computerized reliability analysis, pitch axis fly by wire actuator, flaperon actuation system design trade study, control law synthesis and analysis, flutter mode control and gust load alleviation analysis, and implementation of alternative ACT systems. Extensive analysis of the computer techniques involved in each system is included.

  2. Globular Clusters as Cradles of Life and Advanced Civilizations

    NASA Astrophysics Data System (ADS)

    Di Stefano, R.; Ray, A.

    2016-08-01

    Globular clusters are ancient stellar populations in compact dense ellipsoids. There is no star formation and there are no core-collapse supernovae, but several lines of evidence suggest that globular clusters are rich in planets. If so, and if advanced civilizations can develop there, then the distances between these civilizations and other stars would be far smaller than typical distances between stars in the Galactic disk, facilitating interstellar communication and travel. The potent combination of long-term stability and high stellar densities provides a globular cluster opportunity. Yet the very proximity that promotes interstellar travel also brings danger, as stellar interactions can destroy planetary systems. We find, however, that large portions of many globular clusters are “sweet spots,” where habitable-zone planetary orbits are stable for long times. Globular clusters in our own and other galaxies are, therefore, among the best targets for searches for extraterrestrial intelligence (SETI). We use the Drake equation to compare the likelihood of advanced civilizations in globular clusters to that in the Galactic disk. We also consider free-floating planets, since wide-orbit planets can be ejected to travel through the cluster. Civilizations spawned in globular clusters may be able to establish self-sustaining outposts, reducing the probability that a single catastrophic event will destroy the civilization. Although individual civilizations may follow different evolutionary paths, or even be destroyed, the cluster may continue to host advanced civilizations once a small number have jumped across interstellar space. Civilizations residing in globular clusters could therefore, in a sense, be immortal.

  3. Takeoff certification considerations for large subsonic and supersonic transport airplanes using the Ames flight simulator for advanced aircraft

    NASA Technical Reports Server (NTRS)

    Snyder, C. T.; Drinkwater, F. J., III; Fry, E. B.; Forrest, R. D.

    1973-01-01

    Data for use in development of takeoff airworthiness standards for new aircraft designs such as the supersonic transport (SST) and the large wide-body subsonic jet transport are provided. An advanced motion simulator was used to compare the performance and handling characteristics of three representative large jet transports during specific flight certification tasks. Existing regulatory constraints and methods for determining rotation speed were reviewed, and the effects on takeoff performance of variations in rotation speed, pitch attitude, and pitch attitude rate during the rotation maneuver were analyzed. A limited quantity of refused takeoff information was obtained. The aerodynamics, wing loading, and thrust-to-weight ratio of the subject SST resulted in takeoff speeds limited by climb (rather than lift-off) considerations. Take-off speeds based on U.S. subsonic transport requirements were found unacceptable because of the criticality of rotation-abuse effects on one-engine-inoperative climb performance. Adequate safety margin was provided by takeoff speeds based on proposed Anglo-French supersonic transport (TSS) criteria, with the limiting criterion being that takeoff safety speed be at least 1.15 times the one-engine-inoperative zero-rate-of-climb speed. Various observations related to SST certification are presented.

  4. Integrated Application of Active Controls (IAAC) technology to an advanced subsonic transport project. ACT/Control/Guidance System study. Volume 2: Appendices

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The integrated application of active controls (IAAC) technology to an advanced subsonic transport is reported. Supplementary technical data on the following topics are included: (1) 1990's avionics technology assessment; (2) function criticality assessment; (3) flight deck system for total control and functional features list; (4) criticality and reliability assessment of units; (5) crew procedural function task analysis; and (6) recommendations for simulation mechanization.

  5. Subsonic Investigation of Leading-Edge Flaps Designed for Vortex- and Attached-Flow on a High-Speed Civil Transport Configuration

    NASA Technical Reports Server (NTRS)

    Campbell, Bryan A.; Kemmerly, Guy T.; Kjerstad, Kevin J.; Lessard, Victor R.

    1999-01-01

    A wind tunnel investigation of two separate leading-edge flaps, designed for vortex and attached-flow, respectively, were conducted on a High Speed Civil Transport (HSCT) configuration in the Langley 14- by 22-Foot Subsonic Tunnel. Data were obtained over a Mach number range of 0.12 to 0.27, with corresponding chord Reynolds numbers of 2.50 x 10 (sup 6) to 5.50 x 10 (sup 6). Variations of the leading-edge flap deflection angle were tested with outboard leading-edge flaps deflected 0 deg. and 26.4 deg. Trailing-edge flaps were deflected 0 deg., 10 deg., 12.9 deg., and 20 deg. The longitudinal and lateral aerodynamic data are presented without analysis. A complete tabulated data listing is also presented herein. The data associated with each deflected leading-edge flap indicate L/D improvements over the undeflected configuration. These improvements may be instrumental in providing the necessary lift augmentation required by an actual HSCT during the climb-out and landing phases of the flight envelope. However, further tests will have to be done to assess their full potential.

  6. Preliminary Sizing of 120-Passenger Advanced Civil Rotorcraft Concepts

    NASA Technical Reports Server (NTRS)

    vanAken, Johannes M.; Sinsay, Jeffrey D.

    2006-01-01

    The results of a preliminary sizing study of advanced civil rotorcraft concepts that are capable of carrying 120 passengers over a range of 1,200 nautical miles are presented. The cruise altitude of these rotorcraft is 30,000 ft and the cruise velocity is 350 knots. The mission requires a hover capability, creating a runway independent solution, which might aid in reducing strain on the existing airport infrastructure. Concepts studied are a tiltrotor, a tandem rotor compound, and an advancing blade concept. The first objective of the study is to determine the relative merits of these designs in terms of mission gross weight, engine size, fuel weight, aircraft purchase price, and direct operating cost. The second objective is to identify the enabling technology for these advanced heavy lift civil rotorcraft.

  7. High-lift flow-physics flight experiments on a subsonic civil transport aircraft (B737-100)

    NASA Technical Reports Server (NTRS)

    Vandam, Cornelis P.

    1994-01-01

    As part of the subsonic transport high-lift program, flight experiments are being conducted using NASA Langley's B737-100 to measure the flow characteristics of the multi-element high-lift system at full-scale high-Reynolds-number conditions. The instrumentation consists of hot-film anemometers to measure boundary-layer states, an infra-red camera to detect transition from laminar to turbulent flow, Preston tubes to measure wall shear stress, boundary-layer rakes to measure off-surface velocity profiles, and pressure orifices to measure surface pressure distributions. The initial phase of this research project was recently concluded with two flights on July 14. This phase consisted of a total of twenty flights over a period of about ten weeks. In the coming months the data obtained in this initial set of flight experiments will be analyzed and the results will be used to finalize the instrumentation layout for the next set of flight experiments scheduled for Winter and Spring of 1995. The main goal of these upcoming flights will be: (1) to measure more detailed surface pressure distributions across the wing for a range of flight conditions and flap settings; (2) to visualize the surface flows across the multi-element wing at high-lift conditions using fluorescent mini tufts; and (3) to measure in more detail the changes in boundary-layer state on the various flap elements as a result of changes in flight condition and flap deflection. These flight measured results are being correlated with experimental data measured in ground-based facilities as well as with computational data calculated with methods based on the Navier-Stokes equations or a reduced set of these equations. Also these results provide insight into the extent of laminar flow that exists on actual multi-element lifting surfaces at full-scale high-life conditions. Preliminary results indicate that depending on the deflection angle, the slat and flap elements have significant regions of laminar flow over

  8. Subsonic aerodynamic characteristic of semispan commercial transport model with wing-mounted advanced ducted propeller operating in reverse thrust. [conducted in the Langley 14 by 22 foot subsonic wind tunnel

    NASA Technical Reports Server (NTRS)

    Applin, Zachary T.; Jones, Kenneth M.; Gile, Brenda E.; Quinto, P. Frank

    1994-01-01

    A test was conducted in the Langley 14 by 22 Foot Subsonic Tunnel to determine the effect of the reverse-thrust flow field of a wing-mounted advanced ducted propeller on the aerodynamic characteristics of a semispan subsonic high-lift transport model. The advanced ducted propeller (ADP) model was mounted separately in position alongside the wing so that only the aerodynamic interference of the propeller and nacelle affected the aerodynamic performance of the transport model. Mach numbers ranged from 0.14 to 0.26; corresponding Reynolds numbers ranged from 2.2 to 3.9 x 10(exp 6). The reverse-thrust flow field of the ADP shielded a portion of the wing from the free-stream airflow and reduced both lift and drag. The reduction in lift and drag was a function of ADP rotational speed and free-stream velocity. Test results included ground effects data for the transport model and ADP configuration. The ground plane caused a beneficial increase in drag and an undesirable slight increase in lift. The ADP and transport model performance in ground effect was similar to performance trends observed for out of ground effect. The test results form a comprehensive data set that supports the application of the ADP engine and airplane concept on the next generation of advanced subsonic transports. Before this investigation, the engine application was predicted to have detrimental ground effect characteristics. Ground effect test measurements indicated no critical problems and were the first step in proving the viability of this engine and airplane configuration.

  9. Study of the application of advanced technologies to laminar flow control systems for subsonic transports. Volume 1: Summary

    NASA Technical Reports Server (NTRS)

    Sturgeon, R. F.; Bennett, J. A.; Etchberger, F. R.; Ferrill, R. S.; Meade, L. E.

    1976-01-01

    A study was conducted to evaluate the technical and economic feasibility of applying laminar flow control to the wings and empennage of long-range subsonic transport aircraft compatible with initial operation in 1985. For a design mission range of 10,186 km (5500 n mi), advanced technology laminar-flow-control (LFC) and turbulent-flow (TF) aircraft were developed for both 200 and 400-passenger payloads, and compared on the basis of production costs, direct operating costs, and fuel efficiency. Parametric analyses were conducted to establish the optimum geometry for LFC and TF aircraft, advanced LFC system concepts and arrangements were evaluated, and configuration variations maximizing the effectiveness of LFC were developed. For the final LFC aircraft, analyses were conducted to define maintenance costs and procedures, manufacturing costs and procedures, and operational considerations peculiar to LFC aircraft. Compared to the corresponding advanced technology TF transports, the 200- and 400-passenger LFC aircraft realized reductions in fuel consumption up to 28.2%, reductions in direct operating costs up to 8.4%, and improvements in fuel efficiency, in ssm/lb of fuel, up to 39.4%. Compared to current commercial transports at the design range, the LFC study aircraft demonstrate improvements in fuel efficiency up to 131%. Research and technology requirements requisite to the development of LFC transport aircraft were identified.

  10. Advanced cockpit technology for future civil transport aircraft

    NASA Technical Reports Server (NTRS)

    Hatfield, Jack J.; Parrish, Russell V.

    1990-01-01

    A review is presented of advanced cockpit technology for future civil transport aircraft, covering the present state-of-the-art and major technologies, including flat-panel displays, graphics and pictorial displays. Pilot aiding/automation/human-centered design and imaging sensor/flight systems technology (for low-visibility operations) are also presented. NASA Langley Research Center's recent results in pictorial displays and on future developments in large-screen display technologies are discussed. Major characteristics foreseen for the future high-speed civil transport include fault-tolerant digital avionics and controls/displays with extensive human-centered automation, and unusually clean, uncluttered interface with natural crew interaction via touch, voice/tactile means.

  11. Assessment of the application of advanced technologies to subsonic CTOL transport aircraft

    NASA Technical Reports Server (NTRS)

    Graef, J. D.; Sallee, G. P.; Verges, J. T.

    1974-01-01

    Design studies of the application of advanced technologies to future transport aircraft were conducted. These studies were reviewed from the perspective of an air carrier. A fundamental study of the elements of airplane operating cost was performed, and the advanced technologies were ranked in order of potential profit impact. Recommendations for future study areas are given.

  12. A study of rapid engine response systems for an advanced high subsonic, long range commercial aircraft

    NASA Technical Reports Server (NTRS)

    Barber, J. H.; Bennett, G. W.; Derosier, T. A.

    1973-01-01

    A dynamic model representing the characteristics of an advanced technology study engine (1985 certification time period) was constructed and programmed on an analogue/digital computer. This model was then exercised to study and evaluate a large number of techniques, singly and in combination, to improve engine response. Several effective methods to reduce engine accelerating time are identified.

  13. A study of engine variable geometry systems for an advanced high subsonic long range commercial aircraft

    NASA Technical Reports Server (NTRS)

    Compagnon, M. A.

    1973-01-01

    Several variable geometry high Mach inlet concepts, aimed at meeting a system noise objective of 15 EPNdB below FAR part 36, for a long range, Mach 0.9 advanced commercial transport are assessed and compared to a fixed geometry inlet with multiple splitters. The effects of a variable exhaust nozzle (mixed exhaust engine) on noise, inlet geometry requirements, and economics are also presented. The best variable geometry inlet configuration identified is a variable cowl design which relies on a high throat Mach number for additional inlet noise suppression only at takeoff, and depends entirely on inlet wall treatment for noise suppression at approach power. Relative economic penalties as a function of noise level are also presented.

  14. Improved NASA-ANOPP Noise Prediction Computer Code for Advanced Subsonic Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Kontos, K. B.; Janardan, B. A.; Gliebe, P. R.

    1996-01-01

    Recent experience using ANOPP to predict turbofan engine flyover noise suggests that it over-predicts overall EPNL by a significant amount. An improvement in this prediction method is desired for system optimization and assessment studies of advanced UHB engines. An assessment of the ANOPP fan inlet, fan exhaust, jet, combustor, and turbine noise prediction methods is made using static engine component noise data from the CF6-8OC2, E(3), and QCSEE turbofan engines. It is shown that the ANOPP prediction results are generally higher than the measured GE data, and that the inlet noise prediction method (Heidmann method) is the most significant source of this overprediction. Fan noise spectral comparisons show that improvements to the fan tone, broadband, and combination tone noise models are required to yield results that more closely simulate the GE data. Suggested changes that yield improved fan noise predictions but preserve the Heidmann model structure are identified and described. These changes are based on the sets of engine data mentioned, as well as some CFM56 engine data that was used to expand the combination tone noise database. It should be noted that the recommended changes are based on an analysis of engines that are limited to single stage fans with design tip relative Mach numbers greater than one.

  15. Advanced Technology Subsonic Transport Study: N+3 Technologies and Design Concepts

    NASA Technical Reports Server (NTRS)

    Raymer, Daniel P.; Wilson, Jack; Perkins, H. Douglas; Rizzi, Arthur; Zhang, Mengmeng; RamirezPuentes, Alfredo

    2011-01-01

    Conceptual Research Corporation, the Science of the Possible, has completed a two-year study of concepts and technologies for future airliners in the 180-passenger class. This NASA-funded contract was primarily focused on the ambitious goal of a 70 percent reduction in fuel consumption versus the market-dominating Boeing 737-800. The study is related to the N+3 contracts awarded in 2008 by NASA s Aeronautics Research Mission Directorate to teams led by Boeing, GE Aviation, MIT, and Northrop Grumman, but with more modest goals and funding. CRC s contract featured a predominant emphasis on propulsion and fuel consumption, but since fuel consumption depends upon air vehicle design as much as on propulsion technology, the study included notional vehicle design, analysis, and parametric studies. Other NASA goals including NOx and noise reduction are of long-standing interest but were not highlighted in this study, other than their inclusion in the propulsion system provided to CRC by NASA. The B-737-800 was used as a benchmark, parametric tool, and design point of departure. It was modeled in the RDS-Professional aircraft design software then subjected to extensive parametric variations of parasitic drag, drag-due-to-lift, specific fuel consumption, and unsized empty weight. These studies indicated that the goal of a 70 percent reduction in fuel consumption could be attained with roughly a 30 percent improvement in all four parameters. The results were then fit to a Response Surface and coded for ease of use in subsequent trade studies. Potential technologies to obtain such savings were identified and discussed. More than 16 advanced concept designs were then prepared, attempting to investigate almost every possible emerging concept for application to this class airliner. A preliminary assessment of these concepts was done based on their total wetted area after design normalization of trimmed maximum lift. This assessment points towards a Tailless Airliner concept which

  16. Advanced Subsonic Technology (AST) 22-Inch Low Noise Research Fan Rig Preliminary Design of ADP-Type Fan 3

    NASA Technical Reports Server (NTRS)

    Jeracki, Robert J. (Technical Monitor); Topol, David A.; Ingram, Clint L.; Larkin, Michael J.; Roche, Charles H.; Thulin, Robert D.

    2004-01-01

    This report presents results of the work completed on the preliminary design of Fan 3 of NASA s 22-inch Fan Low Noise Research project. Fan 3 was intended to build on the experience gained from Fans 1 and 2 by demonstrating noise reduction technology that surpasses 1992 levels by 6 dB. The work was performed as part of NASA s Advanced Subsonic Technology (AST) program. Work on this task was conducted in the areas of CFD code validation, acoustic prediction and validation, rotor parametric studies, and fan exit guide vane (FEGV) studies up to the time when a NASA decision was made to cancel the design, fabrication and testing phases of the work. The scope of the program changed accordingly to concentrate on two subtasks: (1) Rig data analysis and CFD code validation and (2) Fan and FEGV optimization studies. The results of the CFD code validation work showed that this tool predicts 3D flowfield features well from the blade trailing edge to about a chord downstream. The CFD tool loses accuracy as the distance from the trailing edge increases beyond a blade chord. The comparisons of noise predictions to rig test data showed that both the tone noise tool and the broadband noise tool demonstrated reasonable agreement with the data to the degree that these tools can reliably be used for design work. The section on rig airflow and inlet separation analysis describes the method used to determine total fan airflow, shows the good agreement of predicted boundary layer profiles to measured profiles, and shows separation angles of attack ranging from 29.5 to 27deg for the range of airflows tested. The results of the rotor parametric studies were significant in leading to the decision not to pursue a new rotor design for Fan 3 and resulted in recommendations to concentrate efforts on FEGV stator designs. The ensuing parametric study on FEGV designs showed the potential for 8 to 10 EPNdB noise reduction relative to the baseline.

  17. RECENT ADVANCES IN COMPUTATIONAL MECHANICS FOR CIVIL ENGINEERING

    NASA Astrophysics Data System (ADS)

    Applied Mechanics Committee, Computational Mechanics Subcommittee,

    In order to clarify mechanical phenomena in civil engineering, it is necessary to improve computational theory and technique in consideration of the particularity of objects to be analyzed and to update computational mechanics focusing on practical use. In addition to the analysis of infrastructure, for damage prediction of natural disasters such as earthquake, tsunami and flood, since it is essential to reflect broad ranges in space and time inherent to fields of civil engineering as well as material properties, it is important to newly develop computational method in view of the particularity of fields of civil engineering. In this context, research trend of methods of computational mechanics which is noteworthy for resolving the complex mechanics problems in civil engineering is reviewed in this paper.

  18. An Analytical Assessment of NASA's N(+)1 Subsonic Fixed Wing Project Noise Goal

    NASA Technical Reports Server (NTRS)

    Berton, Jeffrey J.; Envia, Edmane; Burley, Casey L.

    2010-01-01

    The Subsonic Fixed Wing Project of NASA s Fundamental Aeronautics Program has adopted a noise reduction goal for new, subsonic, single-aisle, civil aircraft expected to replace current 737 and A320 airplanes. These so-called "N+1" aircraft--designated in NASA vernacular as such since they will follow the current, in-service, "N" airplanes--are hoped to achieve certification noise goal levels of 32 cumulative EPNdB under current Stage 4 noise regulations. A notional, N+1, single-aisle, twinjet transport with ultrahigh bypass ratio turbofan engines is analyzed in this study using NASA software and methods. Several advanced noise-reduction technologies are empirically applied to the propulsion system and airframe. Certification noise levels are predicted and compared with the NASA goal.

  19. An Analytical Assessment of NASA's N+1 Subsonic Fixed Wing Project Noise Goal

    NASA Technical Reports Server (NTRS)

    Berton, Jeffrey J.; Envia, Edmane; Burley, Casey L.

    2009-01-01

    The Subsonic Fixed Wing Project of NASA's Fundamental Aeronautics Program has adopted a noise reduction goal for new, subsonic, single-aisle, civil aircraft expected to replace current 737 and A320 airplanes. These so-called 'N+1' aircraft - designated in NASA vernacular as such since they will follow the current, in-service, 'N' airplanes - are hoped to achieve certification noise goal levels of 32 cumulative EPNdB under current Stage 4 noise regulations. A notional, N+1, single-aisle, twinjet transport with ultrahigh bypass ratio turbofan engines is analyzed in this study using NASA software and methods. Several advanced noise-reduction technologies are analytically applied to the propulsion system and airframe. Certification noise levels are predicted and compared with the NASA goal.

  20. Research Data Acquired in World-Class, 60-atm Subsonic Combustion Rig

    NASA Technical Reports Server (NTRS)

    Lee, Chi-Ming; Wey, Changlie

    1999-01-01

    NASA Lewis Research Center's new, world-class, 60-atmosphere (atm) combustor research facility, the Advanced Subsonic Combustion Rig (ASCR), is in operation and producing highly unique research data. Specifically, data were acquired at high pressures and temperatures representative of future subsonic engines from a fundamental flametube configuration with an advanced fuel injector. The data acquired include exhaust emissions as well as pressure and temperature distributions. Results to date represent an improved understanding of nitrous oxide (NOx) formation at high pressures and temperatures and include an NOx emissions reduction greater than 70 percent with an advanced fuel injector at operating pressures to 800 pounds per square inch absolute (psia). ASCR research is an integral part of the Advanced Subsonic Technology (AST) Propulsion Program. This program is developing critical low-emission combustion technology that will result in the next generation of gas turbine engines producing 50 to 70 percent less NOx emissions in comparison to 1996 International Civil Aviation Organization (ICAO) limits. The results to date indicate that the AST low-emission combustor goals of reducing NOx emissions by 50 to 70 percent are feasible. U.S. gas turbine manufacturers have started testing the low-emissions combustors at the ASCR. This collaborative testing will enable the industry to develop low-emission combustors at the high pressure and temperature conditions of future subsonic engines. The first stage of the flametube testing has been implemented. Four GE Aircraft Engines low-emissions fuel injector concepts, three Pratt & Whitney concepts, and two Allison concepts have been tested at Lewis ASCR facility. Subsequently, the flametube was removed from the test stand, and the sector combustor was installed. The testing of low emissions sector has begun. Low-emission combustors developed as a result of ASCR research will enable U.S. engine manufacturers to compete on a

  1. Integrated application of active controls (IAAC) technology to an advanced subsonic transport project. Conventional baseline configuration study

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Characteristics of the U.S. domestic fleet were evaluated to determine the mission characteristics that would have the most impact on U. S. transport fuel use in the future. This resulted in selection of a 197-passenger (plus cargo), about 3710-km (2000 nmi) mission. The existing data base was reviewed and additional analysis was conducted as necessary to complete the technical descriptions. The resulting baseline configuration utilizes a double-lobe, but nearly circular, body with seven-abreast seating. External characteristics feature an 8.71 aspect ratio, 31.5-degree sweep wing, a T-tail empennage, and a dual CF6-6D2, wing-mounted engine arrangement. It provides for 22 LD-2 or 11 LD-3 containers plus bulk cargo in the lower lobe. Passenger/cargo loading, servicing provisions, taxi/takeoff speeds, and field length characteristics are all compatible with accepted airline operations and regulatory provisions. The baseline configuration construction uses conventional aluminum structure except for advanced aluminum alloys and a limited amount of graphite epoxy secondary structure. Modern systems are used, including advanced guidance, navigation, and controls which emphasize application of digital electronics and advanced displays.

  2. Some recent advances of intelligent health monitoring systems for civil infrastructures in HIT

    NASA Astrophysics Data System (ADS)

    Ou, Jinping

    2005-06-01

    The intelligent health monitoring systems more and more become a technique for ensuring the health and safety of civil infrastructures and also an important approach for research of the damage accumulation or even disaster evolving characteristics of civil infrastructures, and attracts prodigious research interests and active development interests of scientists and engineers since a great number of civil infrastructures are planning and building each year in mainland China. In this paper, some recent advances on research, development nad implementation of intelligent health monitoring systems for civil infrastructuresin mainland China, especially in Harbin Institute of Technology (HIT), P.R.China. The main contents include smart sensors such as optical fiber Bragg grating (OFBG) and polivinyllidene fluoride (PVDF) sensors, fatigue life gauges, self-sensing mortar and carbon fiber reinforced polymer (CFRP), wireless sensor networks and their implementation in practical infrastructures such as offshore platform structures, hydraulic engineering structures, large span bridges and large space structures. Finally, the relative research projects supported by the national foundation agencies of China are briefly introduced.

  3. Changing the Landscape of Civil Aviation

    NASA Technical Reports Server (NTRS)

    Russo, Carol J.

    1997-01-01

    NASA is undertaking several bold new initiatives to develop revolutionary technologies for civil aviation. These technologies span the civil aviation fleet from general aviation to large subsonic and supersonic aircraft and promise to bring a new era of new aircraft, lower operation costs, faster more direct flight capabilities, more environmentally friendly aircraft, and safer airline operations. These initiatives have specific quantified goals that require technologies well beyond those currently being developed creating a bold new vision for aeronautics. Revolutionary propulsion systems are enabling for these advancements. This paper gives an overview of the new national aeronautics goals and explores for a selected subset of goals some of the revolutionary technologies will be required to meet some of these goals. The focus of the paper is on the pivotal role propulsion and icing technologies will play in changing the landscape of civil aviation.

  4. Long range view of materials research for civil transport aircraft

    NASA Technical Reports Server (NTRS)

    Ardema, M. D.; Waters, M. H.

    1973-01-01

    The impact of various material technology advancements on the economics of civil transport aircraft is investigated. Benefits of advances in both airframe and engine materials are considered. Benefits are measured primarily by improvements in return on investment for an operator. Materials research and development programs which lead to the greatest benefits are assessed with regards to cost, risk, and commonality with other programs. Emphasis of the paper is on advanced technology subsonic/transonic transports (ATT type aircraft) since these are likely to be the next generation of commercial transports.

  5. Long range view of materials research for civil transport aircraft

    NASA Technical Reports Server (NTRS)

    Ardema, M. D.; Waters, M. H.

    1974-01-01

    The impact of various material technology advancements on the economics of civil transport aircraft is investigated. Benefits of advances in both airframe and engine materials are considered. Benefits are measured primarily by improvements in return on investment for an operator. Materials research and development programs which lead to the greatest benefits are assessed with regards to cost, risk, and commonality with other programs. Emphasis of the paper is on advanced technology subsonic/transonic transports (ATT type aircraft) since these are likely to be the next generation of commercial transports.

  6. Subsonic Aircraft Safety Icing Study

    NASA Technical Reports Server (NTRS)

    Jones, Sharon Monica; Reveley, Mary S.; Evans, Joni K.; Barrientos, Francesca A.

    2008-01-01

    NASA's Integrated Resilient Aircraft Control (IRAC) Project is one of four projects within the agency s Aviation Safety Program (AvSafe) in the Aeronautics Research Mission Directorate (ARMD). The IRAC Project, which was redesigned in the first half of 2007, conducts research to advance the state of the art in aircraft control design tools and techniques. A "Key Decision Point" was established for fiscal year 2007 with the following expected outcomes: document the most currently available statistical/prognostic data associated with icing for subsonic transport, summarize reports by subject matter experts in icing research on current knowledge of icing effects on control parameters and establish future requirements for icing research for subsonic transports including the appropriate alignment. This study contains: (1) statistical analyses of accident and incident data conducted by NASA researchers for this "Key Decision Point", (2) an examination of icing in other recent statistically based studies, (3) a summary of aviation safety priority lists that have been developed by various subject-matter experts, including the significance of aircraft icing research in these lists and (4) suggested future requirements for NASA icing research. The review of several studies by subject-matter experts was summarized into four high-priority icing research areas. Based on the Integrated Resilient Aircraft Control (IRAC) Project goals and objectives, the IRAC project was encouraged to conduct work in all of the high-priority icing research areas that were identified, with the exception of the developing of methods to sense and document actual icing conditions.

  7. Integrated Application of Active Controls (IAAC) technology to an advanced subsonic transport project: Current and advanced act control system definition study

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The Current and Advanced Technology ACT control system definition tasks of the Integrated Application of Active Controls (IAAC) Technology project within the Energy Efficient Transport Program are summarized. The systems mechanize six active control functions: (1) pitch augmented stability; (2) angle of attack limiting; (3) lateral/directional augmented stability; (4) gust load alleviation; (5) maneuver load control; and (6) flutter mode control. The redundant digital control systems meet all function requirements with required reliability and declining weight and cost as advanced technology is introduced.

  8. The transcension hypothesis: Sufficiently advanced civilizations invariably leave our universe, and implications for METI and SETI

    NASA Astrophysics Data System (ADS)

    Smart, John M.

    2012-09-01

    The emerging science of evolutionary developmental ("evo devo") biology can aid us in thinking about our universe as both an evolutionary system, where most processes are unpredictable and creative, and a developmental system, where a special few processes are predictable and constrained to produce far-future-specific emergent order, just as we see in the common developmental processes in two stars of an identical population type, or in two genetically identical twins in biology. The transcension hypothesis proposes that a universal process of evolutionary development guides all sufficiently advanced civilizations into what may be called "inner space," a computationally optimal domain of increasingly dense, productive, miniaturized, and efficient scales of space, time, energy, and matter, and eventually, to a black-hole-like destination. Transcension as a developmental destiny might also contribute to the solution to the Fermi paradox, the question of why we have not seen evidence of or received beacons from intelligent civilizations. A few potential evolutionary, developmental, and information theoretic reasons, mechanisms, and models for constrained transcension of advanced intelligence are briefly considered. In particular, we introduce arguments that black holes may be a developmental destiny and standard attractor for all higher intelligence, as they appear to some to be ideal computing, learning, forward time travel, energy harvesting, civilization merger, natural selection, and universe replication devices. In the transcension hypothesis, simpler civilizations that succeed in resisting transcension by staying in outer (normal) space would be developmental failures, which are statistically very rare late in the life cycle of any biological developing system. If transcension is a developmental process, we may expect brief broadcasts or subtle forms of galactic engineering to occur in small portions of a few galaxies, the handiwork of young and immature

  9. Aeropropulsion 1987. Session 5: Subsonic Propulsion Technology

    NASA Technical Reports Server (NTRS)

    1987-01-01

    NASA is conducting aeropropulsion research over a broad range of Mach numbers. In addition to the high-speed propulsion research described, major progress was recorded in research aimed at the subsonic flight regimes of interest to many commercial and military users. Recent progress and future directions in such areas as small engine technology, rotorcraft transmissions, icing, Hot Section Technology (HOST) and the Advanced Turboprop Program (ATP) are covered.

  10. Performance potential of an advanced technology Mach 3 turbojet engine installed on a conceptual high-speed civil transport

    NASA Technical Reports Server (NTRS)

    Morris, Shelby J., Jr.; Geiselhart, Karl A.; Coen, Peter G.

    1989-01-01

    The performance of an advanced technology conceptual turbojet optimized for a high-speed civil aircraft is presented. This information represents an estimate of performance of a Mach 3 Brayton (gas turbine) cycle engine optimized for minimum fuel burned at supersonic cruise. This conceptual engine had no noise or environmental constraints imposed upon it. The purpose of this data is to define an upper boundary on the propulsion performance for a conceptual commercial Mach 3 transport design. A comparison is presented demonstrating the impact of the technology proposed for this conceptual engine on the weight and other characteristics of a proposed high-speed civil transport. This comparison indicates that the advanced technology turbojet described could reduce the gross weight of a hypothetical Mach 3 high-speed civil transport design from about 714,000 pounds to about 545,000 pounds. The aircraft with the baseline engine and the aircraft with the advanced technology engine are described.

  11. Exploring Advanced Technology Gas Turbine Engine Design and Performance for the Large Civil Tiltrotor (LCTR)

    NASA Technical Reports Server (NTRS)

    Snyder, Christopher A.

    2014-01-01

    A Large Civil Tiltrotor (LCTR) conceptual design was developed as part of the NASA Heavy Lift Rotorcraft Systems Investigation in order to establish a consistent basis for evaluating the benefits of advanced technology for large tiltrotors. The concept has since evolved into the second-generation LCTR2, designed to carry 90 passengers for 1,000 nautical miles at 300 knots, with vertical takeoff and landing capability. This paper explores gas turbine component performance and cycle parameters to quantify performance gains possible for additional improvements in component and material performance beyond those identified in previous LCTR2 propulsion studies and to identify additional research areas. The vehicle-level characteristics from this advanced technology generation 2 propulsion architecture will help set performance levels as additional propulsion and power systems are conceived to meet ever-increasing requirements for mobility and comfort, while reducing energy use, cost, noise and emissions. The Large Civil Tiltrotor vehicle and mission will be discussed as a starting point for this effort. A few, relevant engine and component technology studies, including previous LCTR2 engine study results will be summarized to help orient the reader on gas turbine engine architecture, performance and limitations. Study assumptions and methodology used to explore engine design and performance, as well as assess vehicle sizing and mission performance will then be discussed. Individual performance for present and advanced engines, as well as engine performance effects on overall vehicle size and mission fuel usage, will be given. All results will be summarized to facilitate understanding the importance and interaction of various component and system performance on overall vehicle characteristics.

  12. A Psychoacoustic Evaluation of Noise Signatures from Advanced Civil Transport Aircraft

    NASA Technical Reports Server (NTRS)

    Rizzi, Stephen A.; Christian, Andrew

    2016-01-01

    The NASA Environmentally Responsible Aviation project has been successful in developing and demonstrating technologies for integrated aircraft systems that can simultaneously meet aggressive goals for fuel burn, noise and emissions. Some of the resulting systems substantially differ from the familiar tube and wing designs constituting the current civil transport fleet. This study attempts to explore whether or not the effective perceived noise level metric used in the NASA noise goal accurately reflects human subject response across the range of vehicles considered. Further, it seeks to determine, in a quantitative manner, if the sounds associated with the advanced aircraft are more or less preferable to the reference vehicles beyond any differences revealed by the metric. These explorations are made through psychoacoustic tests in a controlled laboratory environment using simulated stimuli developed from auralizations of selected vehicles based on systems noise assessments.

  13. Overview of the Langley subsonic research effort on SCR configuration

    NASA Technical Reports Server (NTRS)

    Coe, P. L., Jr.; Thomas, J. D.; Huffman, J. K.; Weston, R. P.; Schoonover, W. E., Jr.; Gentry, C. L., Jr.

    1980-01-01

    Recent advances achieved in the subsonic aerodynamics of low aspect ratio, highly swept wing designs are summarized. The most significant of these advances was the development of leading edge deflection concepts which effectively reduce leading edge flow separation. The improved flow attachment results in substantial improvements in low speed performance, significant delay of longitudinal pitch up, increased trailing edge flap effectiveness, and increased lateral control capability. Various additional theoretical and/or experimental studies are considered which, in conjunction with the leading edge deflection studies, form the basis for future subsonic research effort.

  14. Subsonic Ultra Green Aircraft Research

    NASA Technical Reports Server (NTRS)

    Bradley, Marty K.; Droney, Christopher K.

    2011-01-01

    This Final Report summarizes the work accomplished by the Boeing Subsonic Ultra Green Aircraft Research (SUGAR) team in Phase 1, which includes the time period of October 2008 through March 2010. The team consisted of Boeing Research and Technology, Boeing Commercial Airplanes, General Electric, and Georgia Tech. The team completed the development of a comprehensive future scenario for world-wide commercial aviation, selected baseline and advanced configurations for detailed study, generated technology suites for each configuration, conducted detailed performance analysis, calculated noise and emissions, assessed technology risks, and developed technology roadmaps. Five concepts were evaluated in detail: 2008 baseline, N+3 reference, N+3 high span strut braced wing, N+3 gas turbine battery electric concept, and N+3 hybrid wing body. A wide portfolio of technologies was identified to address the NASA N+3 goals. Significant improvements in air traffic management, aerodynamics, materials and structures, aircraft systems, propulsion, and acoustics are needed. Recommendations for Phase 2 concept and technology projects have been identified.

  15. The requirements for a new full scale subsonic wind tunnel

    NASA Technical Reports Server (NTRS)

    Kelly, M. W.; Mckinney, M. O.; Luidens, R. W.

    1972-01-01

    Justification and requirements are presented for a large subsonic wind tunnel capable of testing full scale aircraft, rotor systems, and advanced V/STOL propulsion systems. The design considerations and constraints for such a facility are reviewed, and the trades between facility test capability and costs are discussed.

  16. Second-order subsonic airfoil theory including edge effects

    NASA Technical Reports Server (NTRS)

    Van Dyke, Milton D

    1956-01-01

    Several recent advances in plane subsonic flow theory are combined into a unified second-order theory for airfoil sections of arbitrary shape. The solution is reached in three steps: the incompressible result is found by integration, it is converted into the corresponding subsonic compressible result by means of the second-order compressibility rule, and it is rendered uniformly valid near stagnation points by further rules. Solutions for a number of airfoils are given and are compared with the results of other theories and of experiment. A straight-forward computing scheme is outlined for calculating the surface velocities and pressures on any airfoil at any angle of attack

  17. High-Speed Civil Transport Will Revolutionize Air Travel

    NASA Technical Reports Server (NTRS)

    1998-01-01

    NASA is developing advanced technologies that will allow industry to build a high-speed civil transport that will revolutionize overseas air travel. The technology challenges include developing low-cost materials and structural concepts as well as supersonic engines that can meet stringent noise and emissions standards. NASA's goal is to provide enabling technologies that will reduce the travel time to the Far East by 50 percent within 25 years, and do so at today's subsonic ticket prices. This research is part of NASA's Aeronautics and Space Transportation Technology (ASTT) Enterprise's strategy to sustain U.S. leadership in aeronautics and space. The Enterprise has set bold goals that are grouped into Three Pillars: Global Civil Aviation, Revolutionary Technology Leaps and Access to Space.

  18. Robust, Optimal Subsonic Airfoil Shapes

    NASA Technical Reports Server (NTRS)

    Rai, Man Mohan

    2014-01-01

    A method has been developed to create an airfoil robust enough to operate satisfactorily in different environments. This method determines a robust, optimal, subsonic airfoil shape, beginning with an arbitrary initial airfoil shape, and imposes the necessary constraints on the design. Also, this method is flexible and extendible to a larger class of requirements and changes in constraints imposed.

  19. Challenges and Opportunities for Women To Advance in the Federal Civil Service: Veterans' Preference and Promotions.

    ERIC Educational Resources Information Center

    Mani, Bonnie G.

    1999-01-01

    A study of the effects of veterans' preference on women's careers in the federal civil service between 1975 and 1995 reveals diminishing effects of the preferences and disadvantages to veterans. One can expect little change in federal women's status if veterans' preference is eliminated. (Author)

  20. Back to School on Civil Rights: Advancing the Federal Commitment To Leave No Child Behind.

    ERIC Educational Resources Information Center

    West, Jane

    This report, the second in a series of independent analyses by The National Council on Disability on federal enforcement of civil rights laws looks at more than two decades of federal monitoring and enforcement of compliance with Part B of the Individuals with Disabilities Education Act (IDEA). Separate parts of the report address: (1) development…

  1. A Probabilistic Assessment of NASA Ultra-Efficient Engine Technologies for a Large Subsonic Transport

    NASA Technical Reports Server (NTRS)

    Tong, Michael T.; Jones, Scott M.; Arcara, Philip C., Jr.; Haller, William J.

    2004-01-01

    NASA's Ultra Efficient Engine Technology (UEET) program features advanced aeropropulsion technologies that include highly loaded turbomachinery, an advanced low-NOx combustor, high-temperature materials, intelligent propulsion controls, aspirated seal technology, and an advanced computational fluid dynamics (CFD) design tool to help reduce airplane drag. A probabilistic system assessment is performed to evaluate the impact of these technologies on aircraft fuel burn and NOx reductions. A 300-passenger aircraft, with two 396-kN thrust (85,000-pound) engines is chosen for the study. The results show that a large subsonic aircraft equipped with the UEET technologies has a very high probability of meeting the UEET Program goals for fuel-burn (or equivalent CO2) reduction (15% from the baseline) and LTO (landing and takeoff) NOx reductions (70% relative to the 1996 International Civil Aviation Organization rule). These results are used to provide guidance for developing a robust UEET technology portfolio, and to prioritize the most promising technologies required to achieve UEET program goals for the fuel-burn and NOx reductions.

  2. Civil Rights Laws as Tools to Advance Health in the Twenty-First Century.

    PubMed

    McGowan, Angela K; Lee, Mary M; Meneses, Cristina M; Perkins, Jane; Youdelman, Mara

    2016-01-01

    To improve health in the twenty-first century, to promote both access to and quality of health care services and delivery, and to address significant health disparities, legal and policy approaches, specifically those focused on civil rights, could be used more intentionally and strategically. This review describes how civil rights laws, and their implementation and enforcement, help to encourage health in the United States, and it provides examples for peers around the world. The review uses a broad lens to define health for both classes of individuals and their communities--places where people live, learn, work, and play. Suggestions are offered for improving health and equity broadly, especially within societal groups and marginalized populations. These recommendations include multisectorial approaches that focus on the social determinants of health.

  3. Advancing civil rights, the next generation: the Genetic Information Nondiscrimination Act of 2008 and beyond.

    PubMed

    Tan, Morse Hyun-Myung

    2009-01-01

    On the leading edge of civil rights law and bioethics/healthcare law, this Article provides the first law review analysis of the recently passed Genetic Information Nondiscrimination Act (GINA) of 2008, which extends important protection against discrimination in health insurance and employment. GINA also bolsters genetic research by freeing research subjects from the threat of genetic discrimination. This Article demonstrates how GINA further protects this society against the rising dangers of genetic discrimination beyond previously existing federal and state law.

  4. Civil applications of high-speed rotorcraft and powered-lift aircraft configurations

    NASA Technical Reports Server (NTRS)

    Albers, James A.; Zuk, John

    1987-01-01

    Advanced subsonic vertical and short takeoff and landing (V/STOL) aircraft configurations offer new transportation options for civil applications. Described is a range of vehicles from low-disk to high-disk loading aircraft, including high-speed rotorcraft, V/STOL aircraft, and short takeoff and landing (STOL) aircraft. The status and advantages of the various configurations are described. Some of these show promise for relieving congestion in high population-density regions and providing transportation opportunities for low population-density regions.

  5. Civil applications of high speed rotorcraft and powered lift aircraft configurations

    NASA Technical Reports Server (NTRS)

    Albers, James A.; Zuk, John

    1988-01-01

    Advanced subsonic vertical and short takeoff and landing (V/STOL) aircraft configurations offer new transportation options for civil applications. Described is a range of vehicles from low-disk to high-disk loading aircraft, including high-speed rotorcraft, V/STOL aircraft, and short takeoff and landing (STOL) aircraft. The status and advantages of the various configurations are described. Some of these show promise for relieving congestion in high population-density regions and providing transportation opportunities for low population-density regions.

  6. Robust, optimal subsonic airfoil shapes

    NASA Technical Reports Server (NTRS)

    Rai, Man Mohan (Inventor)

    2008-01-01

    Method system, and product from application of the method, for design of a subsonic airfoil shape, beginning with an arbitrary initial airfoil shape and incorporating one or more constraints on the airfoil geometric parameters and flow characteristics. The resulting design is robust against variations in airfoil dimensions and local airfoil shape introduced in the airfoil manufacturing process. A perturbation procedure provides a class of airfoil shapes, beginning with an initial airfoil shape.

  7. Detection of Extraterrestrial Civilizations via the Spectral Signature of Advanced Interstellar Spacecraft

    NASA Astrophysics Data System (ADS)

    Zubrin, Robert

    1994-07-01

    This paper examines the possibility of detecting extraterrestrial civilizations by means of searching for the spectral signature of their interstellar transportation systems. The advantage of such an approach is that the characteristic power levels associated with interstellar transportation systems are many orders of magnitude greater than those required for communication, and so the signal strength may be much greater. Furthermore, unlike communication which is governed by a fairly arbitrary selection of technology and mutually agreed upon conventions, interstellar transportation systems are governed much more stringently by the laws of physics. For purposes of the present analysis we consider 4 methods of interstellar propulsion, the principles of which are fairly well understood. These are anti-matter rockets, fusion rockets, fission rockets, all of which can be used to either accelerate or decelerate a spacecraft, and magnetic sails, which can be used to decelerate a spacecraft by creating drag against the interstellar medium. The types of radiation emitted by each of these propulsion systems is described, and the signal strength for starships of a characteristic mass of 1 million tonnes traveling at speeds and acceleration levels characteristic of the various propulsion systems is estimated. It is shown that for the power level of ships considered, the high energy gamma radiation emitted by the anti-matter, fusion and fission propulsion systems would be undetectable at interstellar distances. Better opportunities for detection would be the bremsstrahlung radiation from the plasma confinement systems of fusion devices, which might be detectable at distances of about 1 light year, and visible light emitted from the radiators of anti-matter driven photon rocket, which might be detectable by the Hubble Space Telescope at a distance of several hundred light years provided the rocket nozzle is oriented towards the Earth. The most detectable form of starship

  8. Medical management of the traumatic consequences of civil unrest incidents: causation, clinical approaches, needs and advanced planning criteria.

    PubMed

    Ballantyne, Bryan

    2006-01-01

    In the context of this review, civil unrest is defined as disharmony, expressive dissatisfaction and/or disagreement between members of a community, which leads to a situation of competitive aggression that may find expression as disruption of organisation, conflicts, damage to property and injuries. Such a breakdown of harmonious relationships, which may result in property damage and human injuries that may be threatening to life, varies in magnitude from participation of a very few individuals up to the involvement of large crowds of people, which may evolve into a full-scale riot. It is the latter situation often involving demonstrators, opposing groups and law enforcement personnel that can result in multiple casualties and present a very significant challenge to the resources of local healthcare institutions. The causation of civil unrest incidents is multifactorial and has generic, specific and potentiating elements. With the current national and international societal, political and discriminatory problems, it is likely that civil unrest incidents on both small and large scales will continue to occur at a high and possibly increasing rate on a worldwide basis, and for these not infrequent incidents, the medical community should be in a state of informed preparation. The circumstances of civil unrest incidents are very variable with respect to causation, overall magnitude, frequency, timing, geographical location, numbers of persons involved, demographics of participants, influence of extremists, confrontation with opposing groups and control measures used by law enforcement agencies. Methods used by police and security forces for the control of civil unrest incidents, if advanced negotiations with organisers and verbal warnings have failed, fall basically into two categories: physical and chemical measures. Physical methods include restraint holds, truncheons, batons, mounted horses, projectiles (such as bean bags, plastic and rubber bullets), water cannons

  9. Advanced Earth-to-orbit propulsion technology program overview: Impact of civil space technology initiative

    NASA Technical Reports Server (NTRS)

    Stephenson, Frank W., Jr.

    1988-01-01

    The NASA Earth-to-Orbit (ETO) Propulsion Technology Program is dedicated to advancing rocket engine technologies for the development of fully reusable engine systems that will enable space transportation systems to achieve low cost, routine access to space. The program addresses technology advancements in the areas of engine life extension/prediction, performance enhancements, reduced ground operations costs, and in-flight fault tolerant engine operations. The primary objective is to acquire increased knowledge and understanding of rocket engine chemical and physical processes in order to evolve more realistic analytical simulations of engine internal environments, to derive more accurate predictions of steady and unsteady loads, and using improved structural analyses, to more accurately predict component life and performance, and finally to identify and verify more durable advanced design concepts. In addition, efforts were focused on engine diagnostic needs and advances that would allow integrated health monitoring systems to be developed for enhanced maintainability, automated servicing, inspection, and checkout, and ultimately, in-flight fault tolerant engine operations.

  10. Applications of advanced V/STOL aircraft concepts to civil utility missions. Volume 2: Appendices

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The linear performance definition curves for the lift fan aircraft, tilt rotor aircraft, and advanced helicopter are given. The computer program written to perform the mission analysis for this study is also documented, and examples of its use are shown. Methods used to derive the performance coefficients for use in the mission analysis of the lift fan aircraft are described.

  11. Civil Engineering Applications of Ground Penetrating Radar Recent Advances @ the ELEDIA Research Center

    NASA Astrophysics Data System (ADS)

    Salucci, Marco; Tenuti, Lorenza; Nardin, Cristina; Oliveri, Giacomo; Viani, Federico; Rocca, Paolo; Massa, Andrea

    2014-05-01

    The application of non-destructive testing and evaluation (NDT/NDE) methodologies in civil engineering has raised a growing interest during the last years because of its potential impact in several different scenarios. As a consequence, Ground Penetrating Radar (GPR) technologies have been widely adopted as an instrument for the inspection of the structural stability of buildings and for the detection of cracks and voids. In this framework, the development and validation of GPR algorithms and methodologies represents one of the most active research areas within the ELEDIA Research Center of the University of Trento. More in detail, great efforts have been devoted towards the development of inversion techniques based on the integration of deterministic and stochastic search algorithms with multi-focusing strategies. These approaches proved to be effective in mitigating the effects of both nonlinearity and ill-posedness of microwave imaging problems, which represent the well-known issues arising in GPR inverse scattering formulations. More in detail, a regularized multi-resolution approach based on the Inexact Newton Method (INM) has been recently applied to subsurface prospecting, showing a remarkable advantage over a single-resolution implementation [1]. Moreover, the use of multi-frequency or frequency-hopping strategies to exploit the information coming from GPR data collected in time domain and transformed into its frequency components has been proposed as well. In this framework, the effectiveness of the multi-resolution multi-frequency techniques has been proven on synthetic data generated with numerical models such as GprMax [2]. The application of inversion algorithms based on Bayesian Compressive Sampling (BCS) [3][4] to GPR is currently under investigation, as well, in order to exploit their capability to provide satisfactory reconstructions in presence of single and multiple sparse scatterers [3][4]. Furthermore, multi-scaling approaches exploiting level

  12. NASA's Subsonic Jet Transport Noise Reduction Research

    NASA Technical Reports Server (NTRS)

    Powell, Clemans A.; Preisser, John S.

    2000-01-01

    Although new jet transport airplanes in today s fleet are considerably quieter than the first jet transports introduced about 40 years ago, airport community noise continues to be an important environmental issue. NASA s Advanced Subsonic Transport (AST) Noise Reduction program was begun in 1994 as a seven-year effort to develop technology to reduce jet transport noise 10 dB relative to 1992 technology. This program provides for reductions in engine source noise, improvements in nacelle acoustic treatments, reductions in the noise generated by the airframe, and improvements in the way airplanes are operated in the airport environs. These noise reduction efforts will terminate at the end of 2001 and it appears that the objective will be met. However, because of an anticipated 3-8% growth in passenger and cargo operations well into the 21st Century and the slow introduction of new the noise reduction technology into the fleet, world aircraft noise impact will remain essentially constant until about 2020 to 2030 and thereafter begin to rise. Therefore NASA has begun planning with the Federal Aviation Administration, industry, universities and environmental interest groups in the USA for a new noise reduction initiative to provide technology for significant further reductions.

  13. Benefits associated with advanced technologies applied to a high-speed civil transport concept

    NASA Technical Reports Server (NTRS)

    Ozoroski, L. P.; Shields, E. W.; Fenbert, J. W.; Mcelroy, M. O.

    1993-01-01

    Results of a first-order assessment of the mission performance benefits associated with the technology improvements and goals of the Phase II High-Speed Research (HSR) Program are presented. A breakdown of the four major disciplines resulted in the following estimated TOGW savings from the 1990 vehicle: propulsion at 14.3 percent, structures at 11.7 percent, flight-deck systems at 4.0 percent, and aerodynamics at 15.0 percent. Based on 100 percent success of the HSR Phase II proposed technology advancements, the overall combined impact is estimated to result in a 45 percent reduction in TOGW from a 1990 entry-into-service (EIS) date, which could result in a viable 2005 EIS vehicle with an acceptable TOGW that meets Stage III community noise restrictions. Through supersonic laminar flow control and the possible reduction in reserve fuel requirements resulting from synthetic vision capability, the potential exists for an additional 9.6 percent reduction in TOGW.

  14. The future of very large subsonic transports

    NASA Technical Reports Server (NTRS)

    Justice, R. Steven; Hays, Anthony P.; Parrott, Ed L.

    1996-01-01

    modular design. The VLST will encounter severe restrictions on weight, ground flotation, span, length, and door height to operate at current airports/bases, gates, and cargo loading systems. One option under consideration is for a sea-based VLST, either a conventional seaplane or Wing-In-Ground effect (WIG) vehicle, which would allow greater operational flexibility, while introducing other design challenges such as water impact loads and salt-water corrosion. Lockheed Martin is currently developing a floatplane version of the C-130 Hercules which will provide experience with a modern sea-based aircraft. In addition to its own ongoing research activities, Lockheed Martin is also participating in the NASA Advanced Subsonic Technology, High Speed Research (HSR), and other programs which address some of the technologies needed for the VLST. The VLST will require NASA and US aerospace companies to work together to develop new capabilities and technologies for make the VLST a viable part of transportation beyond 2000.

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

    NASA Technical Reports Server (NTRS)

    Wilkerson, Joseph B.; Smith, Roger L.

    2008-01-01

    sized for a representative civil passenger transport mission, using current technology. Individual advanced technologies are quantified and applied to resize the aircraft, thereby quantifying the net benefit of that technology to the rotorcraft. Estimates of development cost, production cost and operating and support costs are made with a commercial cost estimating program, calibrated to Boeing products with adjustments for future civil production processes. A cost metric of cash direct operating cost per available seat-mile (DOC ASM) is used to compare the cost benefit of the technologies. The same metric is used to compare results with turboprop operating costs. Reduced engine SFC was the most advantageous advanced technology for both rotorcraft concepts. Structural weight reduction was the second most beneficial technology, followed by advanced drive systems and then by technology for rotorcraft performance. Most of the technologies evaluated in this report should apply similarly to conventional helicopters. The implicit assumption is that resources will become available to mature the technologies for fullscale production aircraft. That assumption is certainly the weak link in any forecast of future possibilities. The analysis serves the purpose of identifying which technologies offer the most potential benefit, and thus the ones that should receive the highest priority for continued development. This study directly addressed the following NASA Subsonic Rotary Wing (SRW) subtopics: SR W.4.8.I.J Establish capability for rotorcraft system analysis and SRW. 4.8.I.4 Conduct limited technology benefit assessment on baseline rotorcraft configurations.

  16. Subsonic and transonic propeller noise

    NASA Astrophysics Data System (ADS)

    Lewy, S.; Gounet, H.

    Models for the noise levels from propellers are discussed, with results compared to in-flight measurements. Methods originally applied to noise from light aircraft are modified and extended to high speed passenger aircraft. Noise emitted from propellers has three components: a monopolar emission due to the air displaced by a blade; a bipolar form from average and fluctuating forces exerted by the blades; and a quadripolar component produced by deformation of the streamlines around the blade profile and defined by the Lighthill tensor. The latter is not a factor in the subsonic regime and can be neglected. Attention is given to a formalism which accounts for the sound level along each band, the frequency harmonics at each blade passage, the number of blades, and the rotation rate. The measured directivities of the two components are described. It is found that the radiated noise levels can be reduced in slow aircraft by lowering the peripheral velocity while keeping the same power with more blades. Calculations including the quadripolar term are necessary for modeling noise levels in transonic propellers.

  17. Far-Field Turbulent Vortex-Wake/Exhaust Plume Interaction for Subsonic and HSCT Airplanes

    NASA Technical Reports Server (NTRS)

    Kandil, Osama A.; Adam, Ihab; Wong, Tin-Chee

    1996-01-01

    Computational study of the far-field turbulent vortex-wake/exhaust plume interaction for subsonic and high speed civil transport (HSCT) airplanes is carried out. The Reynolds-averaged Navier-Stokes (NS) equations are solved using the implicit, upwind, Roe-flux-differencing, finite-volume scheme. The two-equation shear stress transport model of Menter is implemented with the NS solver for turbulent-flow calculation. For the far-field study, the computations of vortex-wake interaction with the exhaust plume of a single engine of a Boeing 727 wing in a holding condition and two engines of an HSCT in a cruise condition are carried out using overlapping zonal method for several miles downstream. These results are obtained using the computer code FTNS3D. The results of the subsonic flow of this code are compared with those of a parabolized NS solver known as the UNIWAKE code.

  18. Unsteady Aerodynamics - Subsonic Compressible Inviscid Case

    NASA Technical Reports Server (NTRS)

    Balakrishnan, A. V.

    1999-01-01

    This paper presents a new analytical treatment of Unsteady Aerodynamics - the linear theory covering the subsonic compressible (inviscid) case - drawing on some recent work in Operator Theory and Functional Analysis. The specific new results are: (a) An existence and uniqueness proof for the Laplace transform version of the Possio integral equation as well as a new closed form solution approximation thereof. (b) A new representation for the time-domain solution of the subsonic compressible aerodynamic equations emphasizing in particular the role of the initial conditions.

  19. 14 CFR 91.805 - Final compliance: Subsonic airplanes.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Final compliance: Subsonic airplanes. 91... § 91.805 Final compliance: Subsonic airplanes. Except as provided in §§ 91.809 and 91.811, on and after January 1, 1985, no person may operate to or from an airport in the United States any subsonic...

  20. 14 CFR 91.805 - Final compliance: Subsonic airplanes.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Final compliance: Subsonic airplanes. 91... § 91.805 Final compliance: Subsonic airplanes. Except as provided in §§ 91.809 and 91.811, on and after January 1, 1985, no person may operate to or from an airport in the United States any subsonic...

  1. NASA Subsonic Rotary Wing Project-Multidisciplinary Analysis and Technology Development: Overview

    NASA Technical Reports Server (NTRS)

    Yamauchi, Gloria K.

    2009-01-01

    This slide presentation reviews the objectives of the Multidisciplinary Analysis and Technology Development (MDATD) in the Subsonic Rotary Wing project. The objectives are to integrate technologies and analyses to enable advanced rotorcraft and provide a roadmap to guide Level 1 and 2 research. The MDATD objectives will be met by conducting assessments of advanced technology benefits, developing new or enhanced design tools, and integrating Level 2 discipline technologies to develop and enable system-level analyses and demonstrations.

  2. Unsteady Subsonic and Transonic Potential Flow over Helicopter Rotor Blades

    NASA Technical Reports Server (NTRS)

    Isom, M. P.

    1974-01-01

    Differential equations and boundary conditions for a rotor blade in forward flight, with subsonic or transonic tip Mach number, are derived. A variety of limiting flow regimes determined by different limits involving blade thickness ratio, aspect ratio, advance ratio and maximum tip Mach number is discussed. The transonic problem is discussed in some detail, and in particular the conditions that make this problem quasi-steady or essentially unsteady are determined. Asymptotic forms of equations and boundary conditions that are valid in an appropriately scaled region of the tip and an azimuthal sector on the advancing side are derived. The equations are then put in a form that is valid from the blade tip inboard through the strip theory region.

  3. NASA Subsonic Rotary Wing Project

    NASA Technical Reports Server (NTRS)

    Young, Larry A.

    2009-01-01

    This slide presentation will outline the rationale for, and the initial results of, a contractor study being performed by a SAIC-led team of Bell Helicopter Textron, Sensis, and Optimal Synthesis. Together, this team represents an extensive body of subject matter expertise as related to rotorcraft technologies and design, airspace demand modeling simulation, and terminal area operations and flight path planning. The initial conceptual design results of a fleet of civil tiltrotor aircraft ranging in size from 10 to 120 passengers is a key highlight of the work to be presented. The intent of this presentation is to begin to provide the general community of rotorcraft researchers, manufacturers, and end-users an appreciation of the criticality of interjecting rotorcraft-specific technology and concepts of operation issues into Next Gen airspace requirements

  4. High-speed civil transport study: Special factors

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Studies relating to environmental factors associated with high speed civil transports were conducted. Projected total engine emissions for year 2015 fleets of several subsonic/supersonic transport fleet scenarios, discussion of sonic boom reduction methods, discussion of community noise level requirements, fuels considerations, and air traffic control impact are presented.

  5. Airfoil shape for flight at subsonic speeds

    DOEpatents

    Whitcomb, Richard T.

    1976-01-01

    An airfoil having an upper surface shaped to control flow accelerations and pressure distribution over the upper surface and to prevent separation of the boundary layer due to shock wave formulation at high subsonic speeds well above the critical Mach number. A highly cambered trailing edge section improves overall airfoil lifting efficiency.

  6. Civil Rights

    EPA Pesticide Factsheets

    EPA's Civil Rights Program enforces federal civil rights laws that prohibit discrimination against members of the public by recipients of EPA funds, and protects employees and applicants for employment from discrimination.

  7. Civil air transport: A fresh look at power-by-wire and fly-by-light

    NASA Astrophysics Data System (ADS)

    Sundberg, Gale R.

    1990-05-01

    Power-by-wire (PBW) is a key element under subsonic transport flight systems technology with potential savings of over 10 percent in gross take-off-weight and in fuel consumption compared to today's transport aircraft. The PBW technology substitutes electrical actuation in place of centralized hydraulics, uses internal starter-motor/generators and eliminates the need for variable engine bleed air to supply cabin comfort. The application of advanced fiber optics to the electrical power system controls, to built-in-test (BITE) equipment, and to fly-by-light (FBL) flight controls provides additional benefits in lightning and high energy radio frequency (HERF) immunity over existing mechanical or even fly-by-wire controls. The program plan is reviewed and a snapshot is given of the key technologies and their benefits to all future aircraft, both civil and military.

  8. Flow quality measurements in compressible subsonic flows

    NASA Technical Reports Server (NTRS)

    Stainback, P. Calvin; Johnson, Charles B.

    1987-01-01

    The purpose is to re-examine the heat transfer from a hot-wire probe in the compressible subsonic flow regime; describe the three-wire hot-wire probe calibration and data reduction techniques used to measure the velocity, density, and total temperature fluctuation; and present flow quality results obtained in the Langley 0.3 meter Transonic Cryogenic Wind Tunnel and in flight with the NASA JetStar from the same three-wire hot-wire probe.

  9. Materials and Structures Research for Gas Turbine Applications Within the NASA Subsonic Fixed Wing Project

    NASA Technical Reports Server (NTRS)

    Hurst, Janet

    2011-01-01

    A brief overview is presented of the current materials and structures research geared toward propulsion applications for NASA s Subsonic Fixed Wing Project one of four projects within the Fundamental Aeronautics Program of the NASA Aeronautics Research Mission Directorate. The Subsonic Fixed Wing (SFW) Project has selected challenging goals which anticipate an increasing emphasis on aviation s impact upon the global issue of environmental responsibility. These goals are greatly reduced noise, reduced emissions and reduced fuel consumption and address 25 to 30 years of technology development. Successful implementation of these demanding goals will require development of new materials and structural approaches within gas turbine propulsion technology. The Materials and Structures discipline, within the SFW project, comprise cross-cutting technologies ranging from basic investigations to component validation in laboratory environments. Material advances are teamed with innovative designs in a multidisciplinary approach with the resulting technology advances directed to promote the goals of reduced noise and emissions along with improved performance.

  10. A crew-centered flight deck design philosophy for High-Speed Civil Transport (HSCT) aircraft

    NASA Technical Reports Server (NTRS)

    Palmer, Michael T.; Rogers, William H.; Press, Hayes N.; Latorella, Kara A.; Abbott, Terence S.

    1995-01-01

    Past flight deck design practices used within the U.S. commercial transport aircraft industry have been highly successful in producing safe and efficient aircraft. However, recent advances in automation have changed the way pilots operate aircraft, and these changes make it necessary to reconsider overall flight deck design. The High Speed Civil Transport (HSCT) mission will likely add new information requirements, such as those for sonic boom management and supersonic/subsonic speed management. Consequently, whether one is concerned with the design of the HSCT, or a next generation subsonic aircraft that will include technological leaps in automated systems, basic issues in human usability of complex systems will be magnified. These concerns must be addressed, in part, with an explicit, written design philosophy focusing on human performance and systems operability in the context of the overall flight crew/flight deck system (i.e., a crew-centered philosophy). This document provides such a philosophy, expressed as a set of guiding design principles, and accompanied by information that will help focus attention on flight crew issues earlier and iteratively within the design process. This document is part 1 of a two-part set.

  11. CFD Prediction of Magnus Effect in Subsonic to Supersonic Flight

    DTIC Science & Technology

    2009-09-01

    CFD Prediction of Magnus Effect in Subsonic to Supersonic Flight by James DeSpirito ARL-TR-4929 September 2009...of Magnus Effect in Subsonic to Supersonic Flight James DeSpirito Weapons and Materials Research Directorate, ARL...TITLE AND SUBTITLE CFD Prediction of Magnus Effect in Subsonic to Supersonic Flight 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT

  12. Analysis of supersonic combustion flow fields with embedded subsonic regions

    NASA Technical Reports Server (NTRS)

    Dash, S.; Delguidice, P.

    1972-01-01

    The viscous characteristic analysis for supersonic chemically reacting flows was extended to include provisions for analyzing embedded subsonic regions. The numerical method developed to analyze this mixed subsonic-supersonic flow fields is described. The boundary conditions are discussed related to the supersonic-subsonic and subsonic-supersonic transition, as well as a heuristic description of several other numerical schemes for analyzing this problem. An analysis of shock waves generated either by pressure mismatch between the injected fluid and surrounding flow or by chemical heat release is also described.

  13. Rectangular subsonic jet flow field measurements

    NASA Technical Reports Server (NTRS)

    Morrison, Gerald L.; Swan, David H.

    1990-01-01

    Flow field measurements of three subsonic rectangular cold air jets are presented. The three cases had aspect ratios of 1x2, 1x4 at a Mach number of 0.09 and an aspect ratio of 1x2 at a Mach number of 0.9. All measurements were made using a 3-D laser Doppler anemometer system. The data includes the mean velocity vector, all Reynolds stress tensor components, turbulent kinetic energy and velocity correlation coefficients. The data are presented in tabular and graphical form. No analysis of the measured data or comparison to other published data is made.

  14. FPGA development for high altitude subsonic parachute testing

    NASA Technical Reports Server (NTRS)

    Kowalski, James E.; Gromov, Konstantin G.; Konefat, Edward H.

    2005-01-01

    This paper describes a rapid, top down requirements-driven design of a Field Programmable Gate Array (FPGA) used in an Earth qualification test program for a new Mars subsonic parachute. The FPGA is used to process and control storage of telemetry data from multiple sensors throughout launch, ascent, deployment and descent phases of the subsonic parachute test.

  15. FPGA development for high altitude subsonic parachute testing

    NASA Technical Reports Server (NTRS)

    Kowalski, James E.; Konefat, Edward H.; Gromovt, Konstantin

    2005-01-01

    This paper describes a rapid, top down requirements-driven design of an FPGA used in an Earth qualification test program for a new Mars subsonic parachute. The FPGA is used to process and store data from multiple sensors at multiple rates during launch, ascent, deployment and descent phases of the subsonic parachute test.

  16. High altitude subsonic parachute field programmable gate array

    NASA Technical Reports Server (NTRS)

    Kowalski, James E.; Gromov, Konstantin; Konefat, Edward H.

    2005-01-01

    This paper describes a rapid, top down requirements-driven design of an FPGA used in an Earth qualification test program for a new Mars subsonic parachute. The FPGA is used to process and control storage of telemetry data from multiple sensors throughout; launch, ascent, deployment and descent phases of the subsonic parachute test.

  17. Atmospheric Effects of Aviation: First Report of the Subsonic Assessment Project

    NASA Technical Reports Server (NTRS)

    Thompson, Anne M. (Editor); Friedl, Randall R. (Editor); Wesoky, Howard L. (Editor)

    1996-01-01

    This document is the first report from the Office of Aeronautics Advanced Subsonic Technology (AST) Program's Subsonic Assessment (SASS) Project. This effort, initiated in late 1993, has as its objective the assessment of the atmospheric effects of the current and predicted future aviation fleet. The two areas of impact are ozone (stratospheric and tropospheric) and radiative forcing. These are driven, respectively, by possible perturbations from aircraft emissions of NOX and soot and/or sulfur-containing particles. The report presents the major questions to which project assessments will be directed (Introduction) and the status of six programmatic elements: Emissions Scenarios, Exhaust Characterization, Near-Field Interactions, Kinetics and Laboratory Studies, Global Modeling, and Atmospheric Observations (field studies).

  18. Searching for extraterrestrial civilizations.

    PubMed

    Kuiper, T B; Morris, M

    1977-05-06

    We have argued that planning for a search for extraterrestrial intelligence should involve a minimum number of assumptions. In view of the feasibility (at our present level of understanding) of using nuclear fusion to effect interstellar travel at a speed of 0.1c, it appears unwarranted (at this time) to assume that it would not occur for at least some technologically advanced civilizations. One cannot even conclude that humans would not attempt this within the next few centuries. On the contrary, the most likely future situation, given the maintenance of technological growth and the absence of extraterrestrial interference, is that our civilization will explore and colonize our galactic neighborhood. A comparison of the time scales of galactic evolution and interstellar travel leads to the conclusion that the galaxy is either essentially empty with respect to technological civilizations or extensively colonized. In the former instance, a SETI would be unproductive. In the latter, a SETI could be fruitful if a signal has been deliberately directed at the earth or at an alien outpost, probe, or communication relay station in our solar system. In the former case, an existing antenna would probably be sufficient to detect the signal. In the latter case, success would depend on the way in which the communications were coded. Failure to detect a signal could permit any of the following conclusions: (i) the galaxy is devoid of technological civilizations, advanced beyond our own, (ii) such civilizations exist, but cannot (for some reason which is presently beyond our ken) engage in interstellar colonization, or (iii) such civilizations are not attempting overt contact with terrestrial civilizations and their intercommunications, if present, are not coded in a simple way. To plan at this time for a high-cost, large-array SETI based on the last two possibilities appears to be rather premature.

  19. 24 CFR 4.28 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 1 2011-04-01 2011-04-01 false Civil penalties. 4.28 Section 4.28... REFORM ACT Prohibition of Advance Disclosure of Funding Decisions § 4.28 Civil penalties. Whenever any... civil money penalty on the employee in accordance with the provisions of 24 CFR part 30....

  20. Searching for extraterrestrial civilizations

    NASA Technical Reports Server (NTRS)

    Kuiper, T. B. H.; Morris, M.

    1977-01-01

    Three interrelated assumptions are critically examined in an attempt to outline a productive strategy for a search for extraterrestrial intelligence. Questions concerning the feasibility of interstellar travel are investigated. It is concluded that the probability of interstellar travel is high enough that, given a modest number of advanced civilizations, at least one of them will engage in interstellar voyages and colonize the galaxy. Assuming, however, that technological civilizations are rare the galaxy would be essentially unpopulated. Attention is given to the present lack of contact with extraterrestrial beings and frequencies for interstellar beacons.

  1. Study of the application of hydrogen fuel to long-range subsonic transport aircraft, volume 2

    NASA Technical Reports Server (NTRS)

    Brewer, G. D.; Morris, R. E.; Lange, R. H.; Moore, J. W.

    1975-01-01

    The feasibility, practicability, and potential advantages/disadvantages of using liquid hydrogen as fuel in long range, subsonic transport aircraft of advanced design were studied. Both passenger and cargo-type aircraft were investigated. To provide a valid basis for comparison, conventional hydrocarbon (Jet A) fueled aircraft were designed to perform identical missions using the same advanced technology and meeting the same operational constraints. The liquid hydrogen and Jet A fueled aircraft were compared on the basis of weight, size, energy utilization, cost, noise, emissions, safety, and operational characteristics. A program of technology development was formulated.

  2. Future Civil Aircraft and Technologies

    NASA Technical Reports Server (NTRS)

    Albers, J.; Zuk, J.

    1989-01-01

    New aircraft technologies are presented that have the potential to expand the air transportation system and reduce congestion through new operating capabilities while also providing greater levels of safety and environmental compatibility. These new capabilities will result from current and planned civil aeronautics technology at the NASA Ames, Lewis, and Langley Research Centers and will cover the complete spectrum of current aircraft and new vehicle concepts including rotorcraft (helicopters and tilt rotors), vertical and short takeoff and landing (V/STOL), and short takeoff and landing (STOL) aircraft, subsonic transports, high-speed transports, and hypersonic/transatmospheric vehicles. New technologies will improve efficiency, affordability, safety, and environmental compatibility of current aircraft and will enable the development of new transportation system. The new capabilities of vehicles could lead to substantial market opportunities and economic growth and could improve the competitive position of the U.S. aerospace industry.

  3. Subsonic Glideback Rocket Demonstrator Flight Testing

    NASA Technical Reports Server (NTRS)

    DeTurris, Dianne J.; Foster, Trevor J.; Barthel, Paul E.; Macy, Daniel J.; Droney, Christopher K.; Talay, Theodore A. (Technical Monitor)

    2001-01-01

    For the past two years, Cal Poly's rocket program has been aggressively exploring the concept of remotely controlled, fixed wing, flyable rocket boosters. This program, embodied by a group of student engineers known as Cal Poly Space Systems, has successfully demonstrated the idea of a rocket design that incorporates a vertical launch pattern followed by a horizontal return flight and landing. Though the design is meant for supersonic flight, CPSS demonstrators are deployed at a subsonic speed. Many steps have been taken by the club that allowed the evolution of the StarBooster prototype to reach its current size: a ten-foot tall, one-foot diameter, composite material rocket. Progress is currently being made that involves multiple boosters along with a second stage, third rocket.

  4. Rectangular subsonic jet flow field measurements

    NASA Technical Reports Server (NTRS)

    Morrison, Gerald L.; Swan, David H.

    1989-01-01

    Flow field measurements are presented of 3 subsonic rectangular cold air jets. The 3 cases presented had aspect ratios of 1 x 2, 1 x 4 at a Mach number of 0.09 and an aspect ratio of 1 x 2 at a Mach number of 0.9. All measurements were made using a 3-D laser Doppler anemoneter system. The presented data includes the mean velocity vector, all Reynolds stress tensor components, turbulent kinetic energy and velocity correlation coefficients. The data is presented in tabular and graphical form. No analysis of the measured data or comparison to other published data is made. All tabular data are available in ASCII format on MS-DOS compatible disks.

  5. a Numerical Model for Subsonic Acoustic Choking.

    NASA Astrophysics Data System (ADS)

    Walkington, Noel John

    In aircraft turbofan inlets, fan generated noise is observed experimentally to be significantly attenuated at high subsonic inlet Mach numbers. This phenomenon cannot be predicted by linear acoustic theory. In order to study the physical process by which this may occur, a numerical algorithm has been developed to solve a related nonlinear problem in one dimensional gas dynamics. The nonlinear solution admits the possibility of wave steepening and shock waves. Approximate solutions are obtained using several finite difference schemes. The boundary conditions required to model an acoustic source and an anechoic termination are developed. The numerical solutions agree closely with those obtained using the method of matched asymptotic expansions. Solutions involving shock waves exhibit a large reduction in the ratio of transmitted to incident power. This offers an explanation for acoustic choking. The results indicate that more power is dissipated as the Mach number, sound amplitude and frequency are increased. These observations are in agreement with those observed experimentally.

  6. On the stability of subsonic thermal fronts

    SciTech Connect

    Ibanez S, Miguel H.; Shchekinov, Yuri; Bessega L, Maria C.

    2005-08-15

    The stability of subsonic thermal fronts against corrugation is analyzed and an exact dispersion relation is obtained taking into account the compressibility of the gas. For heat fronts, this dispersion equation has an unstable root ({omega}{sub ex}) corresponding to the Landau-Darrieus unstable mode ({omega}{sub 0}) modified by the compressional effects. In particular, the exact solution shows a conspicuous maximum very close to the value of the intake Mach number M{sub 1} at which a Chapman-Jouguet deflagration wave behind the heat front is formed. Cooling fronts are stable for corrugation-like disturbances. A maximum damping as well as a maximum in the frequency occur at a value of M{sub 1} depending on the value of the normalized cooling q.

  7. Our Sky Now and Then: Searches for Lost Stars and Impossible Effects as Probes of Advanced Extraterrestrial Civilizations

    NASA Astrophysics Data System (ADS)

    Villarroel, Beatriz; Imaz, Inigo; Bergstedt, Josefine

    2016-09-01

    Searches for extraterrestrial intelligence using large survey data often look for possible signatures of astroengineering. We propose searching for physically impossible effects caused by highly advanced technology by carrying out a search for disappearing galaxies and Milky Way stars. We select ˜10 million objects from USNO-B1.0 with low proper motions (μ < 20 mas yr-1) imaged on the sky in two epochs. We search for objects not found at the expected positions in the Sloan Digital Sky Survey (SDSS) by visually examining images of ˜290,000 USNO-B1.0 objects with no counterpart in the SDSS. We identify some spurious targets in the USNO-B1.0. We find one candidate of interest for follow-up photometry, although it is very uncertain. If the candidate eventually is found, it defines the probability of observing a disappearing-object event in the last decade to less than one in one million in the given samples. Nevertheless, because the complete USNO-B1.0 data set is 100 times larger than any of our samples, we propose an easily accessible citizen science project in search of USNO-B1.0 objects that have disappeared from the SDSS.

  8. Subsonic/supersonic aerodynamic characteristics for a tactical supercruiser

    NASA Technical Reports Server (NTRS)

    Capone, F. J.; Bare, E. A.; Hollenback, D.; Hutchison, R.

    1984-01-01

    A series of cooperative NASA-Langley/Boeing experimental investigations have been conducted to determine the aeropropulsive characteristics of an advanced tactical fighter designed for supersonic cruise. These investigations were conducted in the Langley 16-Foot Transonic and Lewis 10 x 10-Foot Supersonic Wind Tunnels at Mach numbers from 0.60 to 2.47. This fighter is a Mach 2.0, 49,000 pound class vehicle that features a close-coupled canard and underwing propulsion units that utilize multifunction two-dimensional exhaust nozzles. Tests were conducted to determine the basic aerodynamic characteristics of the configuration with flow-through nacelles in which the spillage effects of representative inlets were measured. The effects of thrust-induced forces on overall aerodynamic performance were evaluated with a series of multifunction nozzles installed on air-powered nacelles. An axisymmetric nozzle configuration was also tested to obtain comparative aeropropulsive performance. Trim aerodynamic characteristics for the flow-through and powered configurations and the effect of thrust vectoring at subsonic speeds are presented.

  9. An Overview of NASA's Subsonic Research Aircraft Testbed (SCRAT)

    NASA Technical Reports Server (NTRS)

    Baumann, Ethan; Hernandez, Joe; Ruhf, John C.

    2013-01-01

    National Aeronautics and Space Administration Dryden Flight Research Center acquired a Gulfstream III (GIII) aircraft to serve as a testbed for aeronautics flight research experiments. The aircraft is referred to as SCRAT, which stands for SubsoniC Research Aircraft Testbed. The aircraft's mission is to perform aeronautics research; more specifically raising the Technology Readiness Level (TRL) of advanced technologies through flight demonstrations and gathering high-quality research data suitable for verifying the technologies, and validating design and analysis tools. The SCRAT has the ability to conduct a range of flight research experiments throughout a transport class aircraft's flight envelope. Experiments ranging from flight-testing of a new aircraft system or sensor to those requiring structural and aerodynamic modifications to the aircraft can be accomplished. The aircraft has been modified to include an instrumentation system and sensors necessary to conduct flight research experiments along with a telemetry capability. An instrumentation power distribution system was installed to accommodate the instrumentation system and future experiments. An engineering simulation of the SCRAT has been developed to aid in integrating research experiments. A series of baseline aircraft characterization flights has been flown that gathered flight data to aid in developing and integrating future research experiments. This paper describes the SCRAT's research systems and capabilities.

  10. 7. VIEW NORTHWEST OF SUBSONIC WIND TUNNEL BUILDING TO TRANSONIC ...

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

    7. VIEW NORTHWEST OF SUBSONIC WIND TUNNEL BUILDING TO TRANSONIC WIND TUNNEL BUILDING - Naval Surface Warfare Center, Bounded by Clara Barton Parkway & McArthur Boulevard, Silver Spring, Montgomery County, MD

  11. 5. VIEW NORTHWEST OF SUBSONIC WIND TUNNEL BUILDING TO TRANSONIC ...

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

    5. VIEW NORTHWEST OF SUBSONIC WIND TUNNEL BUILDING TO TRANSONIC WIND TUNNEL BUILDING - Naval Surface Warfare Center, Bounded by Clara Barton Parkway & McArthur Boulevard, Silver Spring, Montgomery County, MD

  12. 1. VIEW SOUTHWEST OF SUBSONIC WIND TUNNEL BUILDING AND TRANSONIC ...

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

    1. VIEW SOUTHWEST OF SUBSONIC WIND TUNNEL BUILDING AND TRANSONIC WIND TUNNEL BUILDING - Naval Surface Warfare Center, Bounded by Clara Barton Parkway & McArthur Boulevard, Silver Spring, Montgomery County, MD

  13. 3. VIEW SOUTHEAST OF TRANSONIC WIND TUNNEL BUILDING TO SUBSONIC ...

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

    3. VIEW SOUTHEAST OF TRANSONIC WIND TUNNEL BUILDING TO SUBSONIC WIND TUNNEL BUILDING - Naval Surface Warfare Center, Bounded by Clara Barton Parkway & McArthur Boulevard, Silver Spring, Montgomery County, MD

  14. SUBSONIC WIND TUNNEL PERFORMANCE ANALYSIS SOFTWARE

    NASA Technical Reports Server (NTRS)

    Eckert, W. T.

    1994-01-01

    This program was developed as an aid in the design and analysis of subsonic wind tunnels. It brings together and refines previously scattered and over-simplified techniques used for the design and loss prediction of the components of subsonic wind tunnels. It implements a system of equations for determining the total pressure losses and provides general guidelines for the design of diffusers, contractions, corners and the inlets and exits of non-return tunnels. The algorithms used in the program are applicable to compressible flow through most closed- or open-throated, single-, double- or non-return wind tunnels or ducts. A comparison between calculated performance and that actually achieved by several existing facilities produced generally good agreement. Any system through which air is flowing which involves turns, fans, contractions etc. (e.g., an HVAC system) may benefit from analysis using this software. This program is an update of ARC-11138 which includes PC compatibility and an improved user interface. The method of loss analysis used by the program is a synthesis of theoretical and empirical techniques. Generally, the algorithms used are those which have been substantiated by experimental test. The basic flow-state parameters used by the program are determined from input information about the reference control section and the test section. These parameters were derived from standard relationships for compressible flow. The local flow conditions, including Mach number, Reynolds number and friction coefficient are determined for each end of each component or section. The loss in total pressure caused by each section is calculated in a form non-dimensionalized by local dynamic pressure. The individual losses are based on the nature of the section, local flow conditions and input geometry and parameter information. The loss forms for typical wind tunnel sections considered by the program include: constant area ducts, open throat ducts, contractions, constant

  15. 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.

  16. 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.

  17. Civil Disobedience.

    ERIC Educational Resources Information Center

    Martz, Carlton

    2000-01-01

    This theme issue looks at three historical and recent instances of civil disobedience. The first article examines the Free Speech Movement, which arose on the Berkeley campus of the University of California in the 1960s. The second article recounts the struggle of Mahatma Gandhi to free India from the British Empire. The final article explores the…

  18. Technologies and Concepts for Reducing the Fuel Burn of Subsonic Transport Aircraft

    NASA Technical Reports Server (NTRS)

    Nickol, Craig L.

    2012-01-01

    There are many technologies under development that have the potential to enable large fuel burn reductions in the 2025 timeframe for subsonic transport aircraft relative to the current fleet. This paper identifies a potential technology suite and analyzes the fuel burn reduction potential of these technologies when integrated into advanced subsonic transport concepts. Advanced tube-and-wing concepts are developed in the single aisle and large twin aisle class, and a hybrid-wing-body concept is developed for the large twin aisle class. The resulting fuel burn reductions for the advanced tube-and-wing concepts range from a 42% reduction relative to the 777-200 to a 44% reduction relative to the 737-800. In addition, the hybrid-wingbody design resulted in a 47% fuel burn reduction relative to the 777-200. Of course, to achieve these fuel burn reduction levels, a significant amount of technology and concept maturation is required between now and 2025. A methodology for capturing and tracking concept maturity is also developed and presented in this paper.

  19. SHARP: Subsonic High Altitude Research Platform

    NASA Technical Reports Server (NTRS)

    Beals, Todd; Burton, Craig; Cabatan, Aileen; Hermano, Christine; Jones, Tom; Lee, Susan; Radloff, Brian

    1991-01-01

    The Universities Space Research Association is sponsoring an undergraduate program which is geared to designing an aircraft that can study the ozone layer at the equator. This aircraft must be able to satisfy four mission profiles. Mission one is a polar mission that ranges from Chile to the South Pole and back to Chile, a total range of 6000 n.mi. at 100,000 ft with a 2500 lb payload. The second mission is also a polar mission, with an altitude of 70,000 ft and an increased payload of 4000 lbs. For the third mission, the aircraft will takeoff at NASA Ames, cruise at 100,000 ft carrying a 2500 lb payload, and land at Puerto Montt, Chile. The final mission requires the aircraft to take off at NASA Ames, cruise at 100,000 ft with a 1000 lb payload, make an excursion to 120,000 ft, and land at Howard AFB, Panama. Three missions require that a subsonic Mach number be maintained due to constraints imposed by the air sampling equipment. The aircraft need not be manned for all four missions. Three aircraft configurations have been determined to be the most suitable for meeting the above requirements. In the event that a requirement cannot be obtained within the given constraints, recommendations for proposal modifications are given.

  20. The numerical simulation of subsonic flutter

    NASA Technical Reports Server (NTRS)

    Strganac, Thomas W.; Mitchum, Maria V.; Mook, Dean T.

    1987-01-01

    The present paper describes a numerical simulation of unsteady, subsonic aeroelastic responses. The technique accounts for aerodynamic nonlinearities associated with angles of attack, vortex-dominated flow, static deformations, and unsteady behavior. The fluid and the wing together are treated as a single dynamic system, and the equations of motion for the structure and flowfield are integrated simultaneously and interactively in the time domain. The method employs an iterative scheme based on a predictor-corrector technique. The aerodynamic loads are computed by the general unsteady vortex-lattice method and are determined simultaneously with the motion of the wing. Two models are used to demonstrate the technique: a rigid wing on an elastic support experiencing plunge and pitch about the elastic axis, and a continuous wing rigidly supported at the root chord experiencing spanwise bending and twisting. The time domain solution coupled with the unsteady vortex-lattice method provides the capability of graphically depicting wing and wake motion. Several graphs that illustrate the time domain behavior of the wing and wake are presented.

  1. Subsonic-transonic stall flutter study

    NASA Technical Reports Server (NTRS)

    Stardter, H.

    1979-01-01

    The objective of the Subsonic/Transonic Stall Flutter Program was to obtain detailed measurements of both the steady and unsteady flow field surrounding a rotor and the mechanical state of the rotor while it was operating in both steady and flutter modes to provide a basis for future analysis and for development of theories describing the flutter phenomenon. The program revealed that while all blades flutter at the same frequency, they do not flutter at the same amplitude, and their interblade phase angles are not equal. Such a pattern represents the superposition of a number of rotating nodal diameter patterns, each characterized by a different amplitude and different phase indexing, but each rotating at a speed that results in the same flutter frequency as seen in the rotor system. Review of the steady pressure contours indicated that flutter may alter the blade passage pressure distribution. The unsteady pressure amplitude contour maps reveal regions of high unsteady pressure amplitudes near the leading edge, lower amplitudes near the trailing.

  2. The Cylinder and Semicylinder in Subsonic Flow

    NASA Technical Reports Server (NTRS)

    Bingham, Harry J.; Weimer, David K..; Griffith, Wayland

    1952-01-01

    In studying the diffraction of shock waves around various two-dimensional obstacles we have observed that flow separation and the formation of vortices contributes in an important way to transient loading of the obstacle. The cases of a cylinder and semicylinder are especially interesting because the breakaway point is not clearly defined as it is for objects having sharp corners. Accordingly a number of experiments have been made in the shock tube to observe the influence of Reynolds number and Mach number on the transient flow patterns about a cylinder and about a semicylinder mounted on a smooth plane. Some differences might be anticipated since the plane would impose a symmetry on the flow and produce a viscous boundary layer for which there is no counterpart with the cylinder. In the course of these experiments it was noted that a condition of steady subsonic flow about both the cylinder and semicylinder was approached. Thus a comparison with von Karrnan's theoretical calculation of the drag on a cylinder, from certain characteristics of its wake or "vortex street", was undertaken.

  3. Aeroelasticity Benchmark Assessment: Subsonic Fixed Wing Program

    NASA Technical Reports Server (NTRS)

    Florance, Jennifer P.; Chwalowski, Pawel; Wieseman, Carol D.

    2010-01-01

    Aeroelasticity Branch will examine other experimental efforts within the Subsonic Fixed Wing (SFW) program (such as testing of the NASA Common Research Model (CRM)) and other NASA programs and assess aeroelasticity issues and research topics.

  4. India and Pakistan Civil-Military Relations

    DTIC Science & Technology

    2015-05-21

    India and Pakistan Civil -Military Relations A Monograph by MAJ Brent Williams United States Army School of Advanced...2015 2. REPORT TYPE Master’s Thesis 3. DATES COVERED (From - To) JUN 2014 – MAY 2015 4. TITLE AND SUBTITLE India and Pakistan Civil Military...explains civil -military relationships throughout a wide range of interactions between a society and the society’s military. The monograph uses this

  5. Subsonic potential aerodynamics for complex configurations - A general theory

    NASA Technical Reports Server (NTRS)

    Morino, L.; Kuo, C.-C.

    1974-01-01

    A general theory of subsonic potential aerodynamic flow around a lifting body having arbitrary shape and motion is presented. By using the Green function method, an integral representation for the velocity potential is obtained for both supersonic and subsonic flow. Under the small perturbation assumption, the potential at any point in the field depends only upon the values of the potential and its normal derivative on the surface of the body. On the surface of the body, this representation reduces to an integro-differential equation relating the potential and its normal derivative (which is known from the boundary conditions) on the surface. The theory is applied to finite-thickness wings in subsonic steady and oscillatory flows.

  6. Subsonic loads on wings having sharp leading edges and tips

    NASA Technical Reports Server (NTRS)

    Kandil, O. A.; Mook, D. T.; Nayfeh, A. H.

    1976-01-01

    A vortex-lattice method for predicting the aerodynamics of wings having separation at the sharp edges in incompressible flows is extended to compressible subsonic flows using a modified Prandtl-Glauert transformation. Numerical results showing the effect of freestream Mach number on the aerodynamic coefficients are compared with available experimental data for several planforms. It is shown that the proposed method is suitable for predicting the aerodynamic loads on low-aspect wings at moderate angles of attack for high subsonic freestream Mach number. The method is limited to angles of attack up to 12 deg for high subsonic freestream Mach number and to angles of attack up to 20 deg for Mach number not exceeding 0.5.

  7. 24 CFR 4.28 - Civil penalties.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Civil penalties. 4.28 Section 4.28 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development HUD REFORM ACT Prohibition of Advance Disclosure of Funding Decisions § 4.28 Civil penalties. Whenever...

  8. Subsonic flow over thin oblique airfoils at zero lift

    NASA Technical Reports Server (NTRS)

    Jones, Robert T

    1948-01-01

    A previous report gave calculations for the pressure distribution over thin oblique airfoils at supersonic speed. The present report extends the calculations to subsonic speeds. It is found that the flows again can be obtained by the superposition of elementary conical flow fields. In the case of the swept-back wing the pressure distributions remain qualitatively similar at subsonic and supersonic speeds. Thus a distribution similar to the Ackeret type of distribution appears on the root sections of the swept-back wing at Mach=0. The resulting positive pressure drag on the root section is balanced by negative drags on outboard sections.

  9. The VIBRA-8 Subsonic Aerodynamic Nuclear Gust Vulnerability Code.

    DTIC Science & Technology

    1979-05-01

    entries along with AA(a=O, M) as given by Eq. (12) to obtain f NP(s-*). Data for the symmetric 64A006 and 64A010 airfoils (6 and 10 percent thick...N.A.C.A. Report 1977, 1952. 5. Stivers, L.S., Jr., Effects of Subsonic Mach Number on the Forces and Pressure Distributions on Four NACA 64A-Series...Airfoil Sections at Angles of Attack as High as 280, NACA TN3162, March 1954. 6. Axelson, J.A., and Haacker, J.F., Subsonic Wing Loadings on a 450 Sweptback

  10. Advanced Civilian Aeronautical Concepts

    NASA Technical Reports Server (NTRS)

    Bushnell, Dennis M.

    1996-01-01

    Paper discusses alternatives to currently deployed systems which could provide revolutionary improvements in metrics applicable to civilian aeronautics. Specific missions addressed include subsonic transports, supersonic transports and personal aircraft. These alternative systems and concepts are enabled by recent and envisaged advancements in electronics, communications, computing and Designer Fluid Mechanics in conjunction with a design approach employing extensive synergistic interactions between propulsion, aerodynamics and structures.

  11. Civil space technology initiative

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The Civil Space Technology Initiative (CSTI) is a major, focused, space technology program of the Office of Aeronautics, Exploration and Technology (OAET) of NASA. The program was initiated to advance technology beyond basic research in order to expand and enhance system and vehicle capabilities for near-term missions. CSTI takes critical technologies to the point at which a user can confidently incorporate the new or expanded capabilities into relatively near-term, high-priority NASA missions. In particular, the CSTI program emphasizes technologies necessary for reliable and efficient access to and operation in Earth orbit as well as for support of scientific missions from Earth orbit.

  12. CFD Assessment of Aerodynamic Degradation of a Subsonic Transport Due to Airframe Damage

    NASA Technical Reports Server (NTRS)

    Frink, Neal T.; Pirzadeh, Shahyar Z.; Atkins, Harold L.; Viken, Sally A.; Morrison, Joseph H.

    2010-01-01

    A computational study is presented to assess the utility of two NASA unstructured Navier-Stokes flow solvers for capturing the degradation in static stability and aerodynamic performance of a NASA General Transport Model (GTM) due to airframe damage. The approach is to correlate computational results with a substantial subset of experimental data for the GTM undergoing progressive losses to the wing, vertical tail, and horizontal tail components. The ultimate goal is to advance the probability of inserting computational data into the creation of advanced flight simulation models of damaged subsonic aircraft in order to improve pilot training. Results presented in this paper demonstrate good correlations with slope-derived quantities, such as pitch static margin and static directional stability, and incremental rolling moment due to wing damage. This study further demonstrates that high fidelity Navier-Stokes flow solvers could augment flight simulation models with additional aerodynamic data for various airframe damage scenarios.

  13. Civil Aviation and the Occupational Outlook

    ERIC Educational Resources Information Center

    Journal of Aerospace Education, 1975

    1975-01-01

    Describes the nature of the aerospace industry and the types of occupations available in the industry as well as information on training, advancement opportunities and the employment outlook in the future of civil aviation. (BR)

  14. Near-Field Noise Computation for a Subsonic Coannular Jet

    NASA Technical Reports Server (NTRS)

    Loh, Ching Y.; Hultgren, Lennart S.; Jorgenson, Philip C. E.

    2008-01-01

    A high-Reynolds-number, subsonic coannular jet is simulated, using a three-dimensional finite-volume LES method, with emphasis on the near field noise. The nozzle geometry used is the NASA Glenn 3BB baseline model. The numerical results are generally in good agreement with existing experimental findings.

  15. 27. VIEW OF EXHAUST AND DEFLECTOR FOR SUBSONIC AERODYNAMICS RESEARCH ...

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

    27. VIEW OF EXHAUST AND DEFLECTOR FOR SUBSONIC AERODYNAMICS RESEARCH LABORATORY, BUILDING 25C, WHICH REPLACED THE 10-FOOT WIND TUNNEL (1991). - Wright-Patterson Air Force Base, Area B, Buildings 25 & 24,10-foot & 20-foot Wind Tunnel Complex, Northeast side of block bounded by K, G, Third, & Fifth Streets, Dayton, Montgomery County, OH

  16. 28. VIEW OF EXHAUST AND DEFLECTOR FOR SUBSONIC AERODYNAMICS RESEARCH ...

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

    28. VIEW OF EXHAUST AND DEFLECTOR FOR SUBSONIC AERODYNAMICS RESEARCH LABORATORY, BUILDING 25C, WHICH REPLACED THE 10-FOOT WIND TUNNEL (1991). - Wright-Patterson Air Force Base, Area B, Buildings 25 & 24,10-foot & 20-foot Wind Tunnel Complex, Northeast side of block bounded by K, G, Third, & Fifth Streets, Dayton, Montgomery County, OH

  17. 26. VIEW OF EXHAUST AND DEFLECTOR FOR SUBSONIC AERODYNAMICS RESEARCH ...

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

    26. VIEW OF EXHAUST AND DEFLECTOR FOR SUBSONIC AERODYNAMICS RESEARCH LABORATORY, BUILDING 25C, WHICH REPLACED THE 10-FOOT WIND TUNNEL (1991). - Wright-Patterson Air Force Base, Area B, Buildings 25 & 24,10-foot & 20-foot Wind Tunnel Complex, Northeast side of block bounded by K, G, Third, & Fifth Streets, Dayton, Montgomery County, OH

  18. Design procedure for low-drag subsonic airfoils

    NASA Technical Reports Server (NTRS)

    Peterson, J. B.; Chen, A. B.

    1975-01-01

    Airfoil has least amount of drag under given restrictions of boundary layer transition position, lift coefficient, thickness ratio, and Reynolds number based on airfoil chord. It is suitable for use as wing and propeller aircraft sections operating at subsonic speeds and for hydrofoil sections and blades for fans, compressors, turbines, and windmills.

  19. Subsonic annular wing theory with application to flow about nacelles

    NASA Technical Reports Server (NTRS)

    Mann, M. J.

    1974-01-01

    A method has recently been developed for calculating the flow over a subsonic nacelle at zero angle of attack. The method makes use of annular wing theory and boundary-layer theory and has shown good agreement with both experimental data and more complex theoretical solutions. The method permits variation of the mass flow by changing the size of a center body.

  20. Wing-Design Program for Subsonic or Supersonic Speeds

    NASA Technical Reports Server (NTRS)

    Carlson, H. W.; Walkley, K. B.

    1986-01-01

    Surface of mildest possible camber generated. WINGDES provides analysis, design capability and is applicable to both subsonic and supersonic flows. Optimization carried out for entire wing or for designated leading- and trailing-edge areas, for design of missionadaptive surfaces. WINGDES written in FORTRAN IV.

  1. Advances in Thin Film Sensor Technologies for Engine Applications

    NASA Technical Reports Server (NTRS)

    Lei, Jih-Fen; Martin, Lisa C.; Will, Herbert A.

    1997-01-01

    Advanced thin film sensor techniques that can provide accurate surface strain and temperature measurements are being developed at NASA Lewis Research Center. These sensors are needed to provide minimally intrusive characterization of advanced materials (such as ceramics and composites) and structures (such as components for Space Shuttle Main Engine, High Speed Civil Transport, Advanced Subsonic Transports and General Aviation Aircraft) in hostile, high-temperature environments and for validation of design codes. This paper presents two advanced thin film sensor technologies: strain gauges and thermocouples. These sensors are sputter deposited directly onto the test articles and are only a few micrometers thick; the surface of the test article is not structurally altered and there is minimal disturbance of the gas flow over the surface. The strain gauges are palladium-13% chromium based and the thermocouples are platinum-13% rhodium vs. platinum. The fabrication techniques of these thin film sensors in a class 1000 cleanroom at the NASA Lewis Research Center are described. Their demonstration on a variety of engine materials, including superalloys, ceramics and advanced ceramic matrix composites, in several hostile, high-temperature test environments are discussed.

  2. Adaptive wall technology for three-dimensional models at high subsonic speeds and aerofoil testing through the speed of sound

    NASA Technical Reports Server (NTRS)

    Lewis, M. C.; Taylor, N. J.; Goodyer, M. J.

    1992-01-01

    Adaptive wall research at the University of Southampton has been directed towards the development of testing techniques for use in nonporous test sections where two flexible walls are profiled in single curvature. This paper highlights the recent advances that have been made in the testing of 2D airfoils through the speed of sound and the testing of 3D models at high subsonic speeds. Techniques have been developed to accommodate the variety of flow regimes encountered in near sonic airfoil tests. The experimental evidence to date suggests that the new techniques coupled with established procedures allow airfoil data, free from top and bottom wall interference, to be gathered from adaptive flexible walled test sections throughout the entire subsonic, transonic and supersonic speed ranges. Techniques applicable to the testing of 3D models have evolved primarily from experience gained by testing sidewall mounted half-wings. Emphasis has been placed upon models with planforms similar to those of current transport wings. Techniques for high subsonic speeds have now been developed to the point where the residual levels of interference are low.

  3. Aero-Mechanical Design Methodology for Subsonic Civil Transport High-Lift Systems

    NASA Technical Reports Server (NTRS)

    vanDam, C. P.; Shaw, S. G.; VanderKam, J. C.; Brodeur, R. R.; Rudolph, P. K. C.; Kinney, D.

    2000-01-01

    In today's highly competitive and economically driven commercial aviation market, the trend is to make aircraft systems simpler and to shorten their design cycle which reduces recurring, non-recurring and operating costs. One such system is the high-lift system. A methodology has been developed which merges aerodynamic data with kinematic analysis of the trailing-edge flap mechanism with minimum mechanism definition required. This methodology provides quick and accurate aerodynamic performance prediction for a given flap deployment mechanism early on in the high-lift system preliminary design stage. Sample analysis results for four different deployment mechanisms are presented as well as descriptions of the aerodynamic and mechanism data required for evaluation. Extensions to interactive design capabilities are also discussed.

  4. History and Civility

    ERIC Educational Resources Information Center

    Schaefer, Larry

    2015-01-01

    Larry Schaefer's history of civility is a succinct summary of the implicit and evolving definitions of civility over 2500 years of civilization. Beginning with the Romans and the root word "civitas," meaning the rights and duties of citizenship, civility appears in classical literature as integral to the roots of democracy in the context…

  5. High speed civil transport

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This report discusses the design and marketability of a next generation supersonic transport. Apogee Aeronautics Corporation has designated its High Speed Civil Transport (HSCT): Supercruiser HS-8. Since the beginning of the Concorde era, the general consensus has been that the proper time for the introduction of a next generation Supersonic Transport (SST) would depend upon the technical advances made in the areas of propulsion (reduction in emissions) and material composites (stronger, lighter materials). It is believed by many in the aerospace industry that these beforementioned technical advances lie on the horizon. With this being the case, this is the proper time to begin the design phase for the next generation HSCT. The design objective for a HSCT was to develop an aircraft that would be capable of transporting at least 250 passengers with baggage at a distance of 5500 nmi. The supersonic Mach number is currently unspecified. In addition, the design had to be marketable, cost effective, and certifiable. To achieve this goal, technical advances in the current SST's must be made, especially in the areas of aerodynamics and propulsion. As a result of these required aerodynamic advances, several different supersonic design concepts were reviewed.

  6. Optimum Climb to Cruise Noise Trajectories for the High Speed Civil Transport

    NASA Technical Reports Server (NTRS)

    Berton, Jeffrey J.

    2003-01-01

    By entraining large quantities of ambient air into advanced ejector nozzles, the jet noise of the proposed High Speed Civil Transport (HSCT) is expected to be reduced to levels acceptable for airport-vicinity noise certification. Away from the airport, however, this entrained air is shut off and the engines are powered up from their cutback levels to provide better thrust for the climb to cruise altitude. Unsuppressed jet noise levels propagating to the ground far from the airport are expected to be high. Complicating this problem is the HSCT's relative noise level with respect to the subsonic commercial fleet of 2010, which is expected to be much quieter than it is today after the retirement of older, louder, domestic stage II aircraft by the year 2000. In this study, the classic energy state approximation theory is extended to calculate trajectories that minimize the climb to cruise noise of the HSCT. The optimizer dynamically chooses the optimal altitude velocity trajectory, the engine power setting, and whether the ejector should be stowed or deployed with respect to practical aircraft climb constraints and noise limits.

  7. On an acoustic field generated by subsonic jet at low Reynolds numbers

    NASA Technical Reports Server (NTRS)

    Yamamoto, K.; Arndt, R. E. A.

    1978-01-01

    An acoustic field generated by subsonic jets at low Reynolds numbers was investigated. This work is motivated by the need to increase the fundamental understanding of the jet noise generation mechanism which is essential to the development of further advanced techniques of noise suppression. The scope of this study consists of two major investigation. One is a study of large scale coherent structure in the jet turbulence, and the other is a study of the Reynolds number dependence of jet noise. With this in mind, extensive flow and acoustic measurements in low Reynolds number turbulent jets (8,930 less than or equal to M less than or equal to 220,000) were undertaken using miniature nozzles of the same configuration but different diameters at various exist Mach numbers (0.2 less than or equal to M less than or equal to 0.9).

  8. 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.

  9. Acoustic and Laser Doppler Anemometer Results for Confluent and 12-Lobed E(exp 3) Mixer Exhaust Systems for Subsonic Jet Noise Reduction

    NASA Technical Reports Server (NTRS)

    Salikuddin, M.; Babbit, R. R.; Shin, H.; Wisler, S.; Janardan, B. A.; Majjigi, R. K.; Bridges, James (Technical Monitor)

    2002-01-01

    The research described in this report has been funded by NASA Glenn Research Center as part of the Advanced Subsonic Technologies (AST) initiative. The program operates under the Large Engine Technologies (LET) as Task Order #3 1. Task Order 31 is a three year research program divided into three subtasks. Subtask A develops the experimental acoustic and aerodynamic subsonic mixed flow exhaust system databases. Subtask B seeks to develop and assess CFD-based aero-acoustic methods for subsonic mixed flow exhaust systems. Subtask B relies on the data obtained from Subtask A to direct and calibrate the aero-acoustic methods development. Subtask C then seeks to utilize both the aero-acoustic data bases developed in Subtask A and the analytical methods developed in Subtask B to define improved subsonic mixed-flow exhaust systems. The mixed flow systems defined in Subtask C will be experimentally demonstrated for improved noise reduction in a scale model aero-acoustic test conducted similarly to the test performed in Subtask A. The overall object of this Task Order is to develop and demonstrate the technology to define a -3EPNdB exhaust system relative to 1992 exhaust system technology.

  10. A study of sound generation in subsonic rotors, volume 2

    NASA Technical Reports Server (NTRS)

    Chalupnik, J. D.; Clark, L. T.

    1975-01-01

    Computer programs were developed for use in the analysis of sound generation by subsonic rotors. Program AIRFOIL computes the spectrum of radiated sound from a single airfoil immersed in a laminar flow field. Program ROTOR extends this to a rotating frame, and provides a model for sound generation in subsonic rotors. The program also computes tone sound generation due to steady state forces on the blades. Program TONE uses a moving source analysis to generate a time series for an array of forces moving in a circular path. The resultant time series are than Fourier transformed to render the results in spectral form. Program SDATA is a standard time series analysis package. It reads in two discrete time series and forms auto and cross covariances and normalizes these to form correlations. The program then transforms the covariances to yield auto and cross power spectra by means of a Fourier transformation.

  11. Effect of Riblets upon Flow Separation in a Subsonic Diffuser

    DTIC Science & Technology

    1988-12-01

    Technology Air University In Partial Fulfillment of the Requirements for the Degree of Master of Science in Aeronautical Engineering Nathan W. Martens...afterburner where the flow leaving the turbine must be 4 slowed from a high subsonic Mach number to a Mach number of about 0.2" (8:305). Physicall ., a...Second Edition). New York: McGraw-Hill Book Company, 1975. 3. Cebeci, Tuncer and A. M. 0. Smith. Analysis of Turbulent Boundary Layers. Orlando: Academic

  12. Development of panel methods for subsonic analysis and design

    NASA Technical Reports Server (NTRS)

    Bristow, D. R.

    1980-01-01

    Two computer programs, developed for subsonic inviscid analysis and design are described. The first solves arbitrary mixed analysis design problems for multielement airfoils in two dimensional flow. The second calculates the pressure distribution for arbitrary lifting or nonlifting three dimensional configurations. In each program, inviscid flow is modelled by using distributed source doublet singularities on configuration surface panels. Numerical formulations and representative solutions are presented for the programs.

  13. Study of the application of hydrogen fuel to long-range subsonic transport aircraft. Volume 1: Summary

    NASA Technical Reports Server (NTRS)

    Brewer, G. D.; Morris, R. E.; Lange, R. H.; Moore, J. W.

    1975-01-01

    The feasibility of using liquid hydrogen as fuel in advanced designs of long range, subsonic transport aircraft is assessed. Both passenger and cargo type aircraft are investigated. Comparisons of physical, performance, and economic parameters of the LH2 fueled designs with conventionally fueled aircraft are presented. Design studies are conducted to determine appropriate characteristics for the hydrogen related systems required on board the aircraft. These studies included consideration of material, structural, and thermodynamic requirements of the cryogenic fuel tanks and fuel systems with the structural support and thermal protection systems.

  14. Test-to-Test Repeatability of Results From a Subsonic Wing-Body Configuration in the National Transonic Facility

    NASA Technical Reports Server (NTRS)

    Mineck, Raymond E.; Pendergraft, Odis C., Jr.

    2000-01-01

    Results from three wind tunnel tests in the National Transonic Facility of a model of an advanced-technology, subsonic-transport wing-body configuration have been analyzed to assess the test-to-test repeatability of several aerodynamic parameters. The scatter, as measured by the prediction interval, in the longitudinal force and moment coefficients increases as the Mach number increases. Residual errors with and without the ESP tubes installed suggest a bias leading to lower drag with the tubes installed. Residual errors as well as average values of the longitudinal force and moment coefficients show that there are small bias errors between the different tests.

  15. Subsonic Flow for the Multidimensional Euler-Poisson System

    NASA Astrophysics Data System (ADS)

    Bae, Myoungjean; Duan, Ben; Xie, Chunjing

    2016-04-01

    We establish the existence and stability of subsonic potential flow for the steady Euler-Poisson system in a multidimensional nozzle of a finite length when prescribing the electric potential difference on a non-insulated boundary from a fixed point at the exit, and prescribing the pressure at the exit of the nozzle. The Euler-Poisson system for subsonic potential flow can be reduced to a nonlinear elliptic system of second order. In this paper, we develop a technique to achieve a priori {C^{1,α}} estimates of solutions to a quasi-linear second order elliptic system with mixed boundary conditions in a multidimensional domain enclosed by a Lipschitz continuous boundary. In particular, we discovered a special structure of the Euler-Poisson system which enables us to obtain {C^{1,α}} estimates of the velocity potential and the electric potential functions, and this leads us to establish structural stability of subsonic flows for the Euler-Poisson system under perturbations of various data.

  16. Aftbody Closure Effects on the Reference H Configuration at Subsonic and Transonic Speeds

    NASA Technical Reports Server (NTRS)

    Wahls, Richard A.; Owens, Lewis R., Jr.; Londenberg, W. Kelly

    1999-01-01

    Experience with afterbody closure effects and accompanying test techniques issues on a High Speed Civil Transport (HSCT)-class configuration is described. An experimental data base has been developed which includes force, moment, and surface pressure data for the High Speed Research (HSR) Reference H configuration with a closed afterbody at subsonic and transonic speeds, and with a cylindrical afterbody at transonic and supersonic speeds. A supporting computational study has been performed using the USM3D unstructured Euler solver for the purposes of computational fluid dynamics (CFD) method assessment and model support system interference assessment with a focus on lower blade mount effects on longitudinal data at transonic speeds. Test technique issues related to a lower blade sting mount strategy are described based on experience in the National Transonic Facility (NTF). The assessment and application of the USM3D code to the afterbody/sting interference problem is discussed. Finally, status and plans to address critical test technique issues and for continuation of the computational study are presented.

  17. Restructuring Civil Affairs for Persistent Engagement

    DTIC Science & Technology

    2010-04-29

    Simpson II U.S. Army School of Advanced Military Studies United States Army Command and General Staff College Fort Leavenworth, Kansas AY 2010...CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Major Samuel K. Simpson II, United States Army 5d. PROJECT NUMBER 5e...should increase and realign the force structure of the reserve and active components civil affairs; split the U.S. Army Civil Affairs and Psychological

  18. Civil Law Glossary.

    ERIC Educational Resources Information Center

    Update on Law-Related Education, 1997

    1997-01-01

    Presents a glossary of civil law terms originally compiled for journalists by the American Bar Association. Defines many essential civil law concepts and practices including compensatory damages, jurisdiction, motion to dismiss, discovery, and remedy. (MJP)

  19. Simulation of Atmospheric-Entry Capsules in the Subsonic Regime

    NASA Technical Reports Server (NTRS)

    Murman, Scott M.; Childs, Robert E.; Garcia, Joseph A.

    2015-01-01

    The accuracy of Computational Fluid Dynamics predictions of subsonic capsule aerodynamics is examined by comparison against recent NASA wind-tunnel data at high-Reynolds-number flight conditions. Several aspects of numerical and physical modeling are considered, including inviscid numerical scheme, mesh adaptation, rough-wall modeling, rotation and curvature corrections for eddy-viscosity models, and Detached-Eddy Simulations of the unsteady wake. All of these are considered in isolation against relevant data where possible. The results indicate that an improved predictive capability is developed by considering physics-based approaches and validating the results against flight-relevant experimental data.

  20. NASA Subsonic Rotary Wing Project - Structures and Materials Discipline

    NASA Technical Reports Server (NTRS)

    Halbig, Michael C.; Johnson, Susan M.

    2008-01-01

    The Structures & Materials Discipline within the NASA Subsonic Rotary Wing Project is focused on developing rotorcraft technologies. The technologies being developed are within the task areas of: 5.1.1 Life Prediction Methods for Engine Structures & Components 5.1.2 Erosion Resistant Coatings for Improved Turbine Blade Life 5.2.1 Crashworthiness 5.2.2 Methods for Prediction of Fatigue Damage & Self Healing 5.3.1 Propulsion High Temperature Materials 5.3.2 Lightweight Structures and Noise Integration The presentation will discuss rotorcraft specific technical challenges and needs as well as details of the work being conducted in the six task areas.

  1. Subsonic/transonic stall flutter investigation of a rotating rig

    NASA Technical Reports Server (NTRS)

    Jutras, R. R.; Fost, R. B.; Chi, R. M.; Beacher, B. F.

    1981-01-01

    Stall flutter is investigated by obtaining detailed quantitative steady and aerodynamic and aeromechanical measurements in a typical fan rotor. The experimental investigation is made with a 31.3 percent scale model of the Quiet Engine Program Fan C rotor system. Both subsonic/transonic (torsional mode) flutter and supersonic (flexural) flutter are investigated. Extensive steady and unsteady data on the blade deformations and aerodynamic properties surrounding the rotor are acquired while operating in both the steady and flutter modes. Analysis of this data shows that while there may be more than one traveling wave present during flutter, they are all forward traveling waves.

  2. Computation of subsonic base flow on a vector processor

    NASA Technical Reports Server (NTRS)

    Rudy, D. H.

    1987-01-01

    Two-dimensional subsonic laminar compressible base flow has been studied using numerical solutions of the time-dependent Navier-Stokes equations. These solutions were obtained using an explicit finite-difference scheme which is highly efficient on a vector processor. The organization of the code for a CDC CYBER-205 computer is described. Solutions were obtained for Mach 0.4 and 0.6 flows past a slender blunt-based model at moderately high Reynolds numbers. The flow in the wake is unsteady with periodic shedding of vortices from the trailing edge. The computed shedding frequency was found to increase with increasing Reynolds number.

  3. Sound radiation from a subsonic rotor subjected to turbulence

    NASA Technical Reports Server (NTRS)

    Sevik, M.

    1974-01-01

    The broadband sound radiated by a subsonic rotor subjected to turbulence in the approach stream has been analyzed. The power spectral density of the sound intensity has been found to depend on a characteristic time scale-namely, the integral scale of the turbulence divided by the axial flow velocity-as well as several length-scale ratios. These consist of the ratio of the integral scale to the acoustic wavelength, rotor radius, and blade chord. Due to the simplified model chosen, only a limited number of cascade parameters appear. Limited comparisons with experimental data indicate good agreement with predicted values.

  4. Acoustic measurement study 40 by 80 foot subsonic wind tunnel

    NASA Technical Reports Server (NTRS)

    1974-01-01

    An acoustical study conducted during the period from September 1, 1973 to April 30, 1974 measured sound pressure levels and vibration amplitudes inside and outside of the subsonic tunnel and on the tunnel structure. A discussion of the technical aspects of the study, the field measurement and data reduction procedures, and results are presentd, and conclusions resulting from the study which bear upon near field and far field tunnel noise, upon the tunnel as an acoustical enclosure, and upon the sources of noise within the tunnel drive system are given.

  5. Solution of the unsteady subsonic thin airfoil problem

    NASA Technical Reports Server (NTRS)

    Williams, M. H.

    1982-01-01

    The problem of a thin airfoil subject to simple harmonic disturbances in a uniform subsonic free stream is solved by extension of a technique developed earlier for a stationary strip vibrating in a uniform fluid. Explicit expressions are given for the lift and moment, acoustic directivity pattern, and total acoustic power for arbitrary upwash and, in particular, for the 'elementary disturbances': plunge, pitch and a stationary transverse gust. Numerical results for a simple skewed gust are presented and compared to the high-frequency asymptotic theory of Martinez and Widnall.

  6. Mitigation of wind tunnel wall interactions in subsonic cavity flows

    SciTech Connect

    Wagner, Justin L.; Casper, Katya Marie; Beresh, Steven J.; Henfling, John F.; Spillers, Russell Wayne; Pruett, Brian Owen Matthew

    2015-03-06

    In this study, the flow over an open aircraft bay is often represented in a wind tunnel with a cavity. In flight, this flow is unconfined, though in experiments, the cavity is surrounded by wind tunnel walls. If untreated, wind tunnel wall effects can lead to significant distortions of cavity acoustics in subsonic flows. To understand and mitigate these cavity–tunnel interactions, a parametric approach was taken for flow over an L/D = 7 cavity at Mach numbers 0.6–0.8. With solid tunnel walls, a dominant cavity tone was observed, likely due to an interaction with a tunnel duct mode. Furthermore, an acoustic liner opposite the cavity decreased the amplitude of the dominant mode and its harmonics, a result observed by previous researchers. Acoustic dampeners were also placed in the tunnel sidewalls, which further decreased the dominant mode amplitudes and peak amplitudes associated with nonlinear interactions between cavity modes. This then indicates that cavity resonance can be altered by tunnel sidewalls and that spanwise coupling should be addressed when conducting subsonic cavity experiments. Though mechanisms for dominant modes and nonlinear interactions likely exist in unconfined cavity flows, these effects can be amplified by the wind tunnel walls.

  7. Mitigation of wind tunnel wall interactions in subsonic cavity flows

    DOE PAGES

    Wagner, Justin L.; Casper, Katya Marie; Beresh, Steven J.; ...

    2015-03-06

    In this study, the flow over an open aircraft bay is often represented in a wind tunnel with a cavity. In flight, this flow is unconfined, though in experiments, the cavity is surrounded by wind tunnel walls. If untreated, wind tunnel wall effects can lead to significant distortions of cavity acoustics in subsonic flows. To understand and mitigate these cavity–tunnel interactions, a parametric approach was taken for flow over an L/D = 7 cavity at Mach numbers 0.6–0.8. With solid tunnel walls, a dominant cavity tone was observed, likely due to an interaction with a tunnel duct mode. Furthermore, anmore » acoustic liner opposite the cavity decreased the amplitude of the dominant mode and its harmonics, a result observed by previous researchers. Acoustic dampeners were also placed in the tunnel sidewalls, which further decreased the dominant mode amplitudes and peak amplitudes associated with nonlinear interactions between cavity modes. This then indicates that cavity resonance can be altered by tunnel sidewalls and that spanwise coupling should be addressed when conducting subsonic cavity experiments. Though mechanisms for dominant modes and nonlinear interactions likely exist in unconfined cavity flows, these effects can be amplified by the wind tunnel walls.« less

  8. Control of Subsonic and Sonic Jets with Limiting Tabs

    NASA Astrophysics Data System (ADS)

    Berrueta, T.; Rathakrishnan, E.

    2017-04-01

    Aerodynamic mixing of subsonic and sonic jets with limiting tabs, with and without corrugations, has been studied experimentally. Limiting tab located at the nozzle exit and at a downstream distance of 0.5D has been considered in this study. Mixing caused by the tab at nozzle exit is found to be better that of tab at 0.5D, for both plain and corrugated geometries. Also, both tabs caused better mixing for underexpanded sonic jets than the correctly expanded sonic jet and subsonic jets. At nozzle pressure ratio 3 the plain tab at the nozzle exit reduced the core by about 56 % and the corrugated tab by about 51 %. But when the plain tab is placed at 0.5D the jet mixing is retarded. However, the corrugated tab at 0.5D enhances the mixing, though not up to the level of the same tab at 0D, at all Mach numbers except 0.6. The maximum reduction of core caused by shifted corrugated tab is 14 % for Mach 0.8 jet.

  9. Subsonic and Supersonic Effects in Bose-Einstein Condensate

    NASA Technical Reports Server (NTRS)

    Zak, Michail

    2003-01-01

    A paper presents a theoretical investigation of subsonic and supersonic effects in a Bose-Einstein condensate (BEC). The BEC is represented by a time-dependent, nonlinear Schroedinger equation that includes terms for an external confining potential term and a weak interatomic repulsive potential proportional to the number density of atoms. From this model are derived Madelung equations, which relate the quantum phase with the number density, and which are used to represent excitations propagating through the BEC. These equations are shown to be analogous to the classical equations of flow of an inviscid, compressible fluid characterized by a speed of sound (g/Po)1/2, where g is the coefficient of the repulsive potential and Po is the unperturbed mass density of the BEC. The equations are used to study the effects of a region of perturbation moving through the BEC. The excitations created by a perturbation moving at subsonic speed are found to be described by a Laplace equation and to propagate at infinite speed. For a supersonically moving perturbation, the excitations are found to be described by a wave equation and to propagate at finite speed inside a Mach cone.

  10. Subsonic Round and Rectangular Twin Jet Flow Effects

    NASA Technical Reports Server (NTRS)

    Bozak, Rick; Wernet, Mark

    2014-01-01

    Subsonic and supersonic aircraft concepts proposed by NASAs Fundamental Aeronautics Program have integrated propulsion systems with asymmetric nozzles. The asymmetry in the exhaust of these propulsion systems creates asymmetric flow and acoustic fields. The flow asymmetries investigated in the current study are from two parallel round, 2:1, and 8:1 aspect ratio rectangular jets at the same nozzle conditions. The flow field was measured with streamwise and cross-stream particle image velocimetry (PIV). A large dataset of single and twin jet flow field measurements was acquired at subsonic jet conditions. The effects of twin jet spacing and forward flight were investigated. For round, 2:1, and 8:1 rectangular twin jets at their closest spacings, turbulence levels between the two jets decreased due to enhanced jet mixing at near static conditions. When the flight Mach number was increased to 0.25, the flow around the twin jet model created a velocity deficit between the two nozzles. This velocity deficit diminished the effect of forward flight causing an increase in turbulent kinetic energy relative to a single jet. Both of these twin jet flow field effects decreased with increasing twin jet spacing relative to a single jet. These variations in turbulent kinetic energy correlate with changes in far-field sound pressure level.

  11. Extension of sonic anemometry to high subsonic Mach number flows

    NASA Astrophysics Data System (ADS)

    Otero, R.; Lowe, K. T.; Ng, W. F.

    2017-03-01

    In the literature, the application of sonic anemometry has been limited to low subsonic Mach number, near-incompressible flow conditions. To the best of the authors’ knowledge, this paper represents the first time a sonic anemometry approach has been used to characterize flow velocity beyond Mach 0.3. Using a high speed jet, flow velocity was measured using a modified sonic anemometry technique in flow conditions up to Mach 0.83. A numerical study was conducted to identify the effects of microphone placement on the accuracy of the measured velocity. Based on estimated error strictly due to uncertainty in time-of-acoustic flight, a random error of +/- 4 m s‑1 was identified for the configuration used in this experiment. Comparison with measurements from a Pitot probe indicated a velocity RMS error of +/- 9 m s‑1. The discrepancy in error is attributed to a systematic error which may be calibrated out in future work. Overall, the experimental results from this preliminary study support the use of acoustics for high subsonic flow characterization.

  12. Steady subsonic flow around finite-thickness wings

    NASA Technical Reports Server (NTRS)

    Kuo, C. C.; Morino, L.

    1975-01-01

    The general method for analyzing steady subsonic potential aerodynamic flow around a lifting body having arbitrary shape is presented. By using the Green function method, an integral representation for the potential is obtained. Under small perturbation assumption, the potential at any point, P, in the field depends only upon the values of the potential and its normal derivative on the surface of the body. Hence if the point P approaches the surface of the body, the representation reduces to an integral equation relating the potential and its normal derivative (which is known from the boundary conditions) on the surface. The question of uniqueness is examined and it is shown that, for thin wings, the operator becomes singular as the thickness approaches zero. This fact may yield numerical problems for very thin wings. However, numerical results obtained for a rectangular wing in subsonic flow show that these problems do not appear even for thickness ratio tau = .001. Comparison with existing results shows that the proposed method is at least as fast and accurate as the lifting surface theories.

  13. Civil Navigation Signal Status

    DTIC Science & Technology

    2015-04-29

    2015 04 29 _GPS Civil Navigation Signal Status UNCLASSIFIED/APPROVED FOR PUBLIC RELEASE UNCLASSIFIED/APPROVED FOR PUBLIC RELEASE Space and Missile...Systems Center Maj Michael Zollars 29 Apr 15 Civil Navigation Signal Status Report Documentation Page Form ApprovedOMB No. 0704-0188 Public...2015 4. TITLE AND SUBTITLE Civil Navigation Signal Status 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d

  14. Understanding the Civil Justice System.

    ERIC Educational Resources Information Center

    Hirshon, Robert E.; Bolduan, Linda M.

    1997-01-01

    Provides a concise and informative overview of the civil justice system. Examines various components and issues including the federal and state court systems, differences between civil and criminal law, background in common law, types of civil law, civil procedure, and the effect and implementation of civil law in everyday life. (MJP)

  15. The prediction of noise and installation effects of high-subsonic dual-stream jets in flight

    NASA Astrophysics Data System (ADS)

    Saxena, Swati

    Both military and civil aircraft in service generate high levels of noise. One of the major contributors to this noise generated from the aircraft is the jet engine exhaust. This makes the study of jet noise and methods to reduce jet noise an active research area with the aim of designing quieter military and commercial aircraft. The current stringent aircraft noise regulations imposed by the Federal Aviation Administration (FAA) and other international agencies, have further raised the need to perform accurate jet noise calculations for more reliable estimation of the jet noise sources. The main aim of the present research is to perform jet noise simulations of single and dual-stream jets with engineering accuracy and assess forward flight effects on the jet noise. Installation effects such as caused by the pylon are also studied using a simplified pylon nozzle configuration. Due to advances in computational power, it has become possible to perform turbulent flow simulations of high speed jets, which leads to more accurate noise predictions. In the present research, a hybrid unsteady RANS-LES parallel multi-block structured grid solver called EAGLEJet is written to perform the nozzle flow calculations. The far-field noise calculation is performed using solutions to the Ffowcs Williams and Hawkings equation. The present calculations use meshes with 5 to 11 million grid points and require about three weeks of computing time with about 100 processors. A baseline single stream convergent nozzle and a dual-stream coaxial convergent nozzle are used for the flow and noise analysis. Calculations for the convergent nozzle are performed at a high subsonic jet Mach number of Mj = 0.9, which is similar to the operating conditions for commercial aircraft engines. A parallel flow gives the flight effect, which is simulated with a co-flow Mach number, Mcf varying from 0.0 to 0.28. The grid resolution effects, statistical properties of the turbulence and the heated jet effects

  16. An Impact-Location Estimation Algorithm for Subsonic Uninhabited Aircraft

    NASA Technical Reports Server (NTRS)

    Bauer, Jeffrey E.; Teets, Edward

    1997-01-01

    An impact-location estimation algorithm is being used at the NASA Dryden Flight Research Center to support range safety for uninhabited aerial vehicle flight tests. The algorithm computes an impact location based on the descent rate, mass, and altitude of the vehicle and current wind information. The predicted impact location is continuously displayed on the range safety officer's moving map display so that the flightpath of the vehicle can be routed to avoid ground assets if the flight must be terminated. The algorithm easily adapts to different vehicle termination techniques and has been shown to be accurate to the extent required to support range safety for subsonic uninhabited aerial vehicles. This paper describes how the algorithm functions, how the algorithm is used at NASA Dryden, and how various termination techniques are handled by the algorithm. Other approaches to predicting the impact location and the reasons why they were not selected for real-time implementation are also discussed.

  17. Subsonic Static and Dynamic Aerodynamics of Blunt Entry Vehicles

    NASA Technical Reports Server (NTRS)

    Mitcheltree, Robert A.; Fremaux, Charles M.; Yates, Leslie A.

    1999-01-01

    The incompressible subsonic aerodynamics of four entry-vehicle shapes with variable c.g. locations are examined in the Langley 20-Foot Vertical Spin Tunnel. The shapes examined are spherically-blunted cones with half-cone angles of 30, 45, and 60 deg. The nose bluntness varies between 0.25 and 0.5 times the base diameter. The Reynolds number based on model diameter for these tests is near 500,000. Quantitative data on attitude and location are collected using a video-based data acquisition system and reduced with a six deg-of-freedom inverse method. All of the shapes examined suffered from strong dynamic instabilities which could produced limit cycles with sufficient amplitudes to overcome static stability of the configuration. Increasing cone half-angle or nose bluntness increases drag but decreases static and dynamic stability.

  18. Review of Propulsion Technologies for N+3 Subsonic Vehicle Concepts

    NASA Technical Reports Server (NTRS)

    Ashcraft, Scott W.; Padron, Andres S.; Pascioni, Kyle A.; Stout, Gary W., Jr.; Huff, Dennis L.

    2011-01-01

    NASA has set aggressive fuel burn, noise, and emission reduction goals for a new generation (N+3) of aircraft targeting concepts that could be viable in the 2035 timeframe. Several N+3 concepts have been formulated, where the term "N+3" indicate aircraft three generations later than current state-of-the-art aircraft, "N". Dramatic improvements need to be made in the airframe, propulsion systems, mission design, and the air transportation system in order to meet these N+3 goals. The propulsion system is a key element to achieving these goals due to its major role with reducing emissions, fuel burn, and noise. This report provides an in-depth description and assessment of propulsion systems and technologies considered in the N+3 subsonic vehicle concepts. Recommendations for technologies that merit further research and development are presented based upon their impact on the N+3 goals and likelihood of being operational by 2035.

  19. Prediction of subsonic vortex shedding from forebodies with chines

    NASA Technical Reports Server (NTRS)

    Mendenhall, Michael R.; Lesieutre, Daniel J.

    1990-01-01

    An engineering prediction method and associated computer code VTXCHN to predict nose vortex shedding from circular and noncircular forebodies with sharp chine edges in subsonic flow at angles of attack and roll are presented. Axisymmetric bodies are represented by point sources and doublets, and noncircular cross sections are transformed to a circle by either analytical or numerical conformal transformations. The lee side vortex wake is modeled by discrete vortices in crossflow planes along the body; thus the three-dimensional steady flow problem is reduced to a two-dimensional, unsteady, separated flow problem for solution. Comparison of measured and predicted surface pressure distributions, flow field surveys, and aerodynamic characteristics are presented for noncircular bodies alone and forebodies with sharp chines.

  20. Subsonic Dynamic Stability Tests of a Sample Return Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Fremaux, C. Michael; Johnson, R. Keith

    2006-01-01

    An investigation has been conducted in the NASA Langley 20-Foot Vertical Spin Tunnel (VST) to determine the subsonic dynamic stability characteristics of a proposed atmospheric entry vehicle for sample return missions. In particular, the effects of changes in aft-body geometry on stability were examined. Freeflying tests of a dynamically scaled model with various geometric features were conducted, including cases in which the model was perturbed to measure dynamic response. Both perturbed and non-perturbed runs were recorded as motion time histories using the VST optical data acquisition system and reduced for post-test analysis. In addition, preliminary results from a static force and moment test of a similar model in the Langley 12-Foot Low Speed Tunnel are presented. Results indicate that the configuration is dynamically stable for the baseline geometry, but exhibits degraded dynamic behavior for the geometry modifications tested.

  1. Estimation of Rotary Stability Derivatives at Subsonic and Transonic Speeds

    NASA Technical Reports Server (NTRS)

    Tobak, Murray; Lessing, Henry C.

    1961-01-01

    The first part of this paper pertains to the estimation of subsonic rotary stability derivatives of wings. The unsteady potential flow problem is solved by a superposition of steady flow solutions. Numerical results for the damping coefficients of triangular wings are presented as functions of aspect ratio and Mach number, and are compared with experimental results over the Mach number range 0 to 1. In the second part, experimental results are used. to point out a close correlation between the nonlinear variations with angle of attack of the static pitching-moment curve slope and the damping-in-pitch coefficient. The underlying basis for the correlation is found as a result of an analysis in which the indicial function concept and. the principle of super-position are adapted to apply to the nonlinear problem. The form of the result suggests a method of estimating nonlinear damping coefficients from results of static wind-tunnel measurements.

  2. Persistent pressure anisotropy in the subsonic magnetosheath region

    NASA Technical Reports Server (NTRS)

    Crooker, N. U.; Siscoe, G. L.; Geller, R. B.

    1976-01-01

    Observations of proton fluxes in the subsonic flow region of the magnetosheath show double peaks as a function of angle in the equatorial plane of the spacecraft. The peaks are separated by a wide angle, usually more than 90 deg. Suggestions of double flux peaks are present in 95 per cent of the data. They are interpreted as the effect of a persistent pressure anisotropy. The clearest cases were analyzed to determine the orientation of the flux peaks relative to the magnetic field and direction of a model hydrodynamic flow. The peaks are shown to be consistent with a greater pressure perpendicular to the field. Possible sources of the pressure anisotropy in the magnetosheath are discussed.

  3. Inviscid and Viscous Interactions in Subsonic Corner Flows

    PubMed Central

    Chung, Kung-Ming; Chang, Po-Hsiung; Chang, Keh-Chin

    2013-01-01

    A flap can be used as a high-lift device, in which a downward deflection results in a gain in lift at a given geometric angle of attack. To characterize the aerodynamic performance of a deflected surface in compressible flows, the present study examines a naturally developed turbulent boundary layer past the convex and concave corners. This investigation involves the analysis of mean and fluctuating pressure distributions. The results obtained indicate strong inviscid-viscous interactions. There are upstream expansion and downstream compression for the convex-corner flows, while the opposite trend is observed for the concave-corner flows. A combined flow similarity parameter, based on the small perturbation theory, is proposed to scale the flow characteristics in both subsonic convex- and concave-corner flows. PMID:23935440

  4. Subsonic Wing Optimization for Handling Qualities Using ACSYNT

    NASA Technical Reports Server (NTRS)

    Soban, Danielle Suzanne

    1996-01-01

    The capability to accurately and rapidly predict aircraft stability derivatives using one comprehensive analysis tool has been created. The PREDAVOR tool has the following capabilities: rapid estimation of stability derivatives using a vortex lattice method, calculation of a longitudinal handling qualities metric, and inherent methodology to optimize a given aircraft configuration for longitudinal handling qualities, including an intuitive graphical interface. The PREDAVOR tool may be applied to both subsonic and supersonic designs, as well as conventional and unconventional, symmetric and asymmetric configurations. The workstation-based tool uses as its model a three-dimensional model of the configuration generated using a computer aided design (CAD) package. The PREDAVOR tool was applied to a Lear Jet Model 23 and the North American XB-70 Valkyrie.

  5. Aeroelastic characteristics of a cascade of mistuned blades in subsonic and supersonic flows. [turbofan engines

    NASA Technical Reports Server (NTRS)

    Kielb, R. E.; Kaza, K. R. V.

    1981-01-01

    The effects of mistuning on flutter and forced response of a cascade in subsonic in subsonic and supersonic flow were investigated. The aerodynamic and structural coupling between the bending and torsional motions and the aerodynamic coupling between the blades were studied. It is shown that frequency mistuning always has a beneficial effect on flutter. For the cascade considered, the potential for raising flutter speed is greater in subsonic than in supersonic flow. Preliminary results for structural damping mistuning show that there are no additional benefits over adding damping mistuning may have either a beneficial or an adverse effect on forced response, depending on the engine order of the excitation and Mach number.

  6. Schools and Civil Defense.

    ERIC Educational Resources Information Center

    Office of Civil Defense (DOD), Washington, DC.

    Civil defense is a planned, coordinated action to protect the population during any emergency whether arising from thermonuclear attack or natural disaster. The Federal Government has assumed four responsibilities--(1) to keep track of the nature of the threat which the civil defense program must meet, (2) to prepare and disseminate information…

  7. Apps for Ancient Civilizations

    ERIC Educational Resources Information Center

    Thompson, Stephanie

    2011-01-01

    This project incorporates technology and a historical emphasis on science drawn from ancient civilizations to promote a greater understanding of conceptual science. In the Apps for Ancient Civilizations project, students investigate an ancient culture to discover how people might have used science and math smartphone apps to make their lives…

  8. Evaluation of laminar flow control system concepts for subsonic commercial transport aircraft

    NASA Technical Reports Server (NTRS)

    1980-01-01

    A study was conducted to evaluate alternatives in the design of laminar flow control (LFC) subsonic commercial transport aircraft for operation in the 1980's period. 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. Alternatives were evaluated in the areas of aerodynamics structures, materials, LFC systems, leading-edge region cleaning and integration of auxiliary systems. Based on these evaluations, concept in each area were selected for further development and testing and ultimate incorporation in the final study aircraft. Relative to a similarly-optimized advanced technology turbulent transport, the final LFC configuration is approximately equal in direct operating cost but provides decreases of 8.2% in gross weight and 21.7% in fuel consumption.

  9. Optimized aerodynamic design process for subsonic transport wing fitted with winglets. [wind tunnel model

    NASA Technical Reports Server (NTRS)

    Kuhlman, J. M.

    1979-01-01

    The aerodynamic design of a wind-tunnel model of a wing representative of that of a subsonic jet transport aircraft, fitted with winglets, was performed using two recently developed optimal wing-design computer programs. Both potential flow codes use a vortex lattice representation of the near-field of the aerodynamic surfaces for determination of the required mean camber surfaces for minimum induced drag, and both codes use far-field induced drag minimization procedures to obtain the required spanloads. One code uses a discrete vortex wake model for this far-field drag computation, while the second uses a 2-D advanced panel wake model. Wing camber shapes for the two codes are very similar, but the resulting winglet camber shapes differ widely. Design techniques and considerations for these two wind-tunnel models are detailed, including a description of the necessary modifications of the design geometry to format it for use by a numerically controlled machine for the actual model construction.

  10. Numerical Simulation of Subsonic and Transonic Propeller Flow. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Snyder, Aaron

    1988-01-01

    The numerical simulation of 3-D transonic flow about a system of propeller blades is investigated. In particular, it is shown that the use of helical coordinates significantly simplifies the form of the governing equation when the propeller system is assumed to be surrounded by an irrotational flow field of an inviscid fluid. The unsteady small disturbance equation, valid for lightly loaded blades and expressed in helical coordinates, is derived from the general blade-fixed potential equation, given for an arbitrary coordinate system. The use of a coordinate system which inherently adapts to the mean flow results in a disturbance equation requiring relatively few terms to accurately model the physics of the flow. Furthermore, the helical coordinate system presented here is novel in that it is periodic in the circumferential direction while, simultaneously, maintaining orthogonal properties at the mean blade locations. The periodic characteristic allows a complete cascade of blades to be treated, and the orthogonality property affords straightforward treatment of blade boundary conditions. An ADI numerical scheme is used to compute the solution of the steady flow as an asymptotic limit of an unsteady flow. As an example of the method, solutions are presented for subsonic and transonic flow about a 5 percent thick bicircular arc blade of an 8-bladed cascade. Both high and low advance ratio cases are computed and include a lifting as well as nonlifting cases. The nonlifting solutions obtained are compared to solutions from a Euler code.

  11. An Overview of NASA's SubsoniC Research Aircraft Testbed (SCRAT)

    NASA Technical Reports Server (NTRS)

    Baumann, Ethan; Hernandez, Joe; Ruhf, John

    2013-01-01

    National Aeronautics and Space Administration Dryden Flight Research Center acquired a Gulfstream III (GIII) aircraft to serve as a testbed for aeronautics flight research experiments. The aircraft is referred to as SCRAT, which stands for SubsoniC Research Aircraft Testbed. The aircraft’s mission is to perform aeronautics research; more specifically raising the Technology Readiness Level (TRL) of advanced technologies through flight demonstrations and gathering high-quality research data suitable for verifying the technologies, and validating design and analysis tools. The SCRAT has the ability to conduct a range of flight research experiments throughout a transport class aircraft’s flight envelope. Experiments ranging from flight-testing of a new aircraft system or sensor to those requiring structural and aerodynamic modifications to the aircraft can be accomplished. The aircraft has been modified to include an instrumentation system and sensors necessary to conduct flight research experiments along with a telemetry capability. An instrumentation power distribution system was installed to accommodate the instrumentation system and future experiments. An engineering simulation of the SCRAT has been developed to aid in integrating research experiments. A series of baseline aircraft characterization flights has been flown that gathered flight data to aid in developing and integrating future research experiments. This paper describes the SCRAT’s research systems and capabilities

  12. A second-generation high speed civil transport: Stingray

    NASA Technical Reports Server (NTRS)

    Engdahl, Sean; Lopes, Kevin; Ngan, Angelen; Perrin, Joseph; Phipps, Marcus; Westman, Blake; Yeo, Urn

    1992-01-01

    The Stingray is the second-generation High Speed Civil Transport (HSCT) designed for the 21st Century. This aircraft is designed to be economically viable and environmentally sound transportation competitive in markets currently dominated by subsonic aircraft such as the Boeing 747 and upcoming McDonnell Douglas MD-12. With the Stringray coming into service in 2005, a ticket price of 21 percent over current subsonic airlines will cover operational costs with a 10 percent return on investment. The cost per aircraft will be $202 million with the Direct Operating Cost equal to $0.072 per mile per seat. This aircraft has been designed to be a realistic aircraft that can be built within the next ten to fifteen years. There was only one main technological improvement factor used in the design, that being for the engine specific fuel consumption. The Stingray, therefore, does not rely on technology that does not exist. The Stingray will be powered by four mixed flow turbofans that meet both nitrous oxide emissions and FAR 36 Stage 3 noise regulations. It will carry 250 passengers a distance of 5200 nautical miles at a speed of Mach 2.4. The shape of the Stingray, while optimized for supersonic flight, is compatible with all current airline facilities in airports around the world. As the demand for economical, high-speed flight increases, the Stingray will be ready and able to meet those demands.

  13. Summary of the Large Civil Tiltrotor (LCTR2) Engine Gearbox Study

    NASA Technical Reports Server (NTRS)

    Snyder, Christopher A.; Robuck, Mark; Wilkerson, Joseph; Nordstrom, Carl

    2010-01-01

    In support of the Fundamental Aeronautics Program, Subsonic Rotary Wing Project, NASA is continuing to study the Large Civil Tiltrotor (LCTR) concept to help define/refine vehicle, system and subsystem attributes. These attributes can then be used to define performance requirements and identify new or advanced technologies to achieve an operational vehicle class. As part of this goal, NASA contracted with The Boeing Company and its subcontractor Rolls-Royce to perform an investigation of different combinations of engine and gearbox variability to achieve a maximum of 50 percent rotor tip speed reduction from hover to cruise conditions. Previous NASA studies identified the 50 percent rotor speed reduction minimized vehicle gross weight and fuel burn. The LCTR2 (LCTR-iteration 2) was the contracted study baseline for initial sizing. Rotor tip speed ratios (cruise to hover) of 100, 77, and 54 percent were analyzed for each combination of engine and gearbox speed reduction to achieve the chosen rotor tip speed ratio. Three different engine and gearbox technology levels were assumed; commercial off-the-shelf (COTS), entry-in-service (EIS) in 2025 and EIS in 2035. These technology levels were applied to determine each particular effect on vehicle gross weight and fuel burn, while other vehicle technologies were assumed constant. This report summarizes the work performed that is being put together into a comprehensive NASA contractor report. Some background on the LCTR concept and baseline vehicle will be given and then a discussion concerning the technical approach utilized. Major study assumptions and results will be presented and discussed. Finally conclusions will be drawn as well as suggestions provided for future efforts.

  14. Refined methods of aeroelastic analysis and optimization. [swept wings, propeller theory, and subsonic flutter

    NASA Technical Reports Server (NTRS)

    Ashley, H.

    1984-01-01

    Graduate research activity in the following areas is reported: the divergence of laminated composite lifting surfaces, subsonic propeller theory and aeroelastic analysis, and cross sectional resonances in wind tunnels.

  15. Climates, Landscapes, and Civilizations

    NASA Astrophysics Data System (ADS)

    Schultz, Colin

    2013-10-01

    Humans are now the dominant driver of global climate change. From ocean acidification to sea level rise, changes in precipitation patterns, and rising temperatures, global warming is presenting us with an uncertain future. However, this is not the first time human civilizations have faced a changing world. In the AGU monograph Climates, Landscapes, and Civilizations, editors Liviu Giosan, Dorian Q. Fuller, Kathleen Nicoll, Rowan K. Flad, and Peter C. Clift explore how some ancient peoples weathered the shifting storms while some faded away. In this interview, Eos speaks with Liviu Giosan about the decay of civilizations, ancient adaptation, and the surprisingly long history of humanity's effect on the Earth.

  16. The evolution of the high-speed civil transport

    NASA Technical Reports Server (NTRS)

    Spearman, M. Leroy

    1994-01-01

    Current research directed toward the technology requirements for a high-speed civil transport (HSCT) airplane is an outgrowth of many years of activity related to air transportation. The purpose was to review some of the events that provided the background upon which current research programs are built. The review will include the subsonic era of transport aircraft and some events of the supersonic era that are related to the development of commercial supersonic transport aircraft. These events include the early NASA in-house studies and industry evaluations, the U.S. Supersonic Transport (SST) Program, the follow-on NASA supersonic cruise research programs, and the issuance of the National Aeronautical Research and Development (R&D) goals. Observations are made concerning some of the factors, both technical and nontechnical, that have had an impact on HSCT studies.

  17. Phoenix: Preliminary design of a high speed civil transport

    NASA Technical Reports Server (NTRS)

    Aguilar, Joseph; Davis, Steven; Jett, Brian; Ringo, Leslie; Stob, John; Wood, Bill

    1992-01-01

    The goal of the Phoenix Design Project was to develop a second generation high speed civil transport (HSCT) that will meet the needs of the traveler and airline industry beginning in the 21st century. The primary emphasis of the HSCT is to take advantage of the growing needs of the Pacific Basin and the passengers who are involved in that growth. A passenger load of 150 persons, a mission range of 5150 nautical miles, and a cruise speed of Mach 2.5 constitutes the primary design points of this HSCT. The design concept is made possible with the use of a well designed double delta wing and four mixed flow engines. Passenger comfort, compatibility with existing airport infrastructure, and cost competitive with current subsonic aircraft make the Phoenix a viable aircraft for the future.

  18. Quasispherical subsonic accretion in X-ray pulsars

    NASA Astrophysics Data System (ADS)

    Shakura, Nikolai I.; Postnov, Konstantin A.; Kochetkova, A. Yu; Hjalmarsdotter, L.

    2013-04-01

    A theoretical model is considered for quasispherical subsonic accretion onto slowly rotating magnetized neutron stars. In this regime, the accreting matter settles down subsonically onto the rotating magnetosphere, forming an extended quasistatic shell. Angular momentum transfer in the shell occurs via large-scale convective motions resulting, for observed pulsars, in an almost iso-angular-momentum \\omega \\sim 1/R^2 rotation law inside the shell. The accretion rate through the shell is determined by the ability of the plasma to enter the magnetosphere due to Rayleigh-Taylor instabilities, with allowance for cooling. A settling accretion regime is possible for moderate accretion rates \\dot M \\lesssim \\dot M_* \\simeq 4\\times 10^{16} g s ^{-1}. At higher accretion rates, a free-fall gap above the neutron star magnetosphere appears due to rapid Compton cooling, and the accretion becomes highly nonstationary. Observations of spin-up/spin-down rates of quasispherically wind accreting equilibrium X-ray pulsars with known orbital periods (e.g., GX 301-2 and Vela X-1) enable us to determine the main dimensionless parameters of the model, as well as to estimate surface magnetic field of the neutron star. For equilibrium pulsars, the independent measurements of the neutron star magnetic field allow for an estimate of the stellar wind velocity of the optical companion without using complicated spectroscopic measurements. For nonequilibrium pulsars, a maximum value is shown to exist for the spin-down rate of the accreting neutron star. From observations of the spin-down rate and the X-ray luminosity in such pulsars (e.g., GX 1+4, SXP 1062, and 4U 2206+54), a lower limit can be put on the neutron star magnetic field, which in all cases turns out to be close to the standard value and which agrees with cyclotron line measurements. Furthermore, both explains the spin-up/spin-down of the pulsar frequency on large time-scales and also accounts for the irregular short

  19. Subsonic Aircraft With Regression and Neural-Network Approximators Designed

    NASA Technical Reports Server (NTRS)

    Patnaik, Surya N.; Hopkins, Dale A.

    2004-01-01

    At the NASA Glenn Research Center, NASA Langley Research Center's Flight Optimization System (FLOPS) and the design optimization testbed COMETBOARDS with regression and neural-network-analysis approximators have been coupled to obtain a preliminary aircraft design methodology. For a subsonic aircraft, the optimal design, that is the airframe-engine combination, is obtained by the simulation. The aircraft is powered by two high-bypass-ratio engines with a nominal thrust of about 35,000 lbf. It is to carry 150 passengers at a cruise speed of Mach 0.8 over a range of 3000 n mi and to operate on a 6000-ft runway. The aircraft design utilized a neural network and a regression-approximations-based analysis tool, along with a multioptimizer cascade algorithm that uses sequential linear programming, sequential quadratic programming, the method of feasible directions, and then sequential quadratic programming again. Optimal aircraft weight versus the number of design iterations is shown. The central processing unit (CPU) time to solution is given. It is shown that the regression-method-based analyzer exhibited a smoother convergence pattern than the FLOPS code. The optimum weight obtained by the approximation technique and the FLOPS code differed by 1.3 percent. Prediction by the approximation technique exhibited no error for the aircraft wing area and turbine entry temperature, whereas it was within 2 percent for most other parameters. Cascade strategy was required by FLOPS as well as the approximators. The regression method had a tendency to hug the data points, whereas the neural network exhibited a propensity to follow a mean path. The performance of the neural network and regression methods was considered adequate. It was at about the same level for small, standard, and large models with redundancy ratios (defined as the number of input-output pairs to the number of unknown coefficients) of 14, 28, and 57, respectively. In an SGI octane workstation (Silicon Graphics

  20. 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.

  1. CFD validation of subsonic turbulent planar shear layers

    NASA Technical Reports Server (NTRS)

    Lai, H. T.; Raju, M. S.

    1993-01-01

    The primary objective of the present study is to assess the limitations and capabilities of RPLUS in predicting the entrainment, mixing, and burning characteristics of a high subsonic planar shear layer; these computations are performed in conjunction with an experiment being conducted at NASA Lewis Research Center. Turbulence is modeled by a two-equation k-epsilon closure modified for compressibility effects. Combustion is modeled by two different models: one in which a finite-rate laminar chemistry model is used for H2-O2 oxidation, and the other based on a composition joint pdf approach to account for the turbulence-chemistry interaction effects. Between upwind and centered differencing schemes, minimal differences are observed for the flow properties of a nonreacting shear layer case studied. In comparison with experimental data, computed growth rates are underpredicted in both reacting and nonreacting cases of a shear layer, but more severely for the reacting flows. However, the qualitative agreement between computation and experiment is reasonably good for the other observable characteristics, and indicative of potential for further improvements.

  2. The 1996 Subsonic Aircraft: Contrail and Cloud Effects Special Study

    NASA Technical Reports Server (NTRS)

    Toon, Owen B.; Condon, Estelle P. (Technical Monitor)

    1996-01-01

    During April 1996 NASA, in conjunction with the DOE, will sponsor a multi-aircraft field campaign to better understand the microphysical and radiative properties of cirrus clouds, the origins of ice nuclei and cloud condensation nuclei in the upper troposphere, and the possible role that the commercial subsonic aircraft fleet might play in altering cloud or aerosol properties. The NASA ER-2 aircraft will be used as a remote sensing platform, while the NASA DC-8 aircraft will be used as an in situ measurement platform. In situ observations will include a full set of size distribution measurements from nano-meter to millimeter sizes, ice water content measurements, gas phase and condensed phase chemical measurements, ice crystal optical phase function measurements, lidar observations of cloud top and cloud base, and atmospheric state measurement. The ER-2 will have lidar, microwave ice water path measurements, as well as visible and infrared spectral measurement. In this presentation the highlights of the mission will be presented. The goal will be to address fundamental questions such as the mode of nucleation of cirrus clouds, the composition of the nuclei on which cirrus form, the degree to which aircraft impact cirrus cloud properties.

  3. Cavity Unsteady-Pressure Measurements at Subsonic and Transonic Speeds

    NASA Technical Reports Server (NTRS)

    Tracy, Maureen B.; Plentovich, E. B.

    1997-01-01

    An experimental investigation was conducted in the Langley 8-Foot Transonic Pressure Tunnel to determine the flow characteristics of rectangular cavities with varying relative dimensions at subsonic and transonic speeds. Cavities were tested with width-to-depth ratios of 1, 4, 8, and 16 for length-to-depth ratios l/h of 1 through 17.5. The maximum cavity depth was 2.4 in., and the turbulent boundary layer approaching the cavity was approximately 0.5 in. thick. Unsteady- and mean static-pressure measurements were made at free-stream Mach numbers from 0.20 to 0.95 at a unit Reynolds number per foot of approximately 3 x 10(exp 6); however, only unsteady-pressure results are presented in this paper. Results indicate that as l/h increases, cavity flows changed from resonant to nonresonant with resonant amplitudes decreasing gradually. Resonant spectra are obtained largely in cavities with mean static-pressure distributions characteristic of open and transitional flows. Resonance sometimes occurred for closed flow. Increasing cavity width or decreasing cavity depth while holding l/h fixed had the effect of increasing resonant amplitudes and sometimes induced resonance. The effects due to changes in width are more pronounced. Decreasing Mach number has the effect of broadening the resonances.

  4. The Impact of Subsonic Twin Jets on Airport Noise

    NASA Technical Reports Server (NTRS)

    Bozak, Richard F.

    2012-01-01

    Subsonic and supersonic aircraft concepts proposed through NASA s Fundamental Aeronautics Program have multiple engines mounted near one another. Engine configurations with multiple jets introduce an asymmetry to the azimuthal directivity of the jet noise. Current system noise predictions add the jet noise from each jet incoherently, therefore, twin jets are estimated by adding 3 EPNdB to the far-field noise radiated from a single jet. Twin jet effects have the ability to increase or decrease the radiated noise to different azimuthal observation locations. Experiments have shown that twin jet effects are reduced with forward flight and increasing spacings. The current experiment investigates the impact of spacing, and flight effects on airport noise for twin jets. Estimating the jet noise radiated from twin jets as that of a single jet plus 3 EPNdB may be sufficient for horizontal twin jets with an s/d of 4.4 and 5.5, where s is the center-to-center spacing and d is the jet diameter. However, up to a 3 EPNdB error could be present for jet spacings with an s/d of 2.6 and 3.2.

  5. CFD validation of subsonic turbulent planar shear layers

    NASA Astrophysics Data System (ADS)

    Lai, H. T.; Raju, M. S.

    1993-06-01

    The primary objective of the present study is to assess the limitations and capabilities of RPLUS in predicting the entrainment, mixing, and burning characteristics of a high subsonic planar shear layer; these computations are performed in conjunction with an experiment being conducted at NASA Lewis Research Center. Turbulence is modeled by a two-equation k-epsilon closure modified for compressibility effects. Combustion is modeled by two different models: one in which a finite-rate laminar chemistry model is used for H2-O2 oxidation, and the other based on a composition joint pdf approach to account for the turbulence-chemistry interaction effects. Between upwind and centered differencing schemes, minimal differences are observed for the flow properties of a nonreacting shear layer case studied. In comparison with experimental data, computed growth rates are underpredicted in both reacting and nonreacting cases of a shear layer, but more severely for the reacting flows. However, the qualitative agreement between computation and experiment is reasonably good for the other observable characteristics, and indicative of potential for further improvements.

  6. Transverse Injection into Subsonic Crossflow with Various Injector Orifice Geometries

    NASA Technical Reports Server (NTRS)

    Foster, Lancert E.; Zaman, Khairul B.

    2010-01-01

    Computational and experimental results are presented for a case study of single injectors employed in 90 deg transverse injection into a non-reacting subsonic flow. Different injector orifice shapes are used (including circular, square, diamond-shaped, and wide rectangular slot), all with constant cross-sectional area, to observe the effects of this variation on injector penetration and mixing. Whereas the circle, square, and diamond injector produce similar jet plumes, the wide rectangular slot produces a plume with less vertical penetration than the others. There is also some evidence that the diamond injector produces slightly faster penetration with less mixing of the injected fluid. In addition, a variety of rectangular injectors were analyzed, with varying length/width ratios. Both experimental and computational data show improved plume penetration with increased streamwise orifice length. 3-D Reynolds-Averaged Navier-Stokes (RANS) results are obtained for the various injector geometries using NCC (National Combustion Code) with the kappa-epsilon turbulence model in multi-species modes on an unstructured grid. Grid sensitivity results are also presented which indicate consistent qualitative trends in the injector performance comparisons with increasing grid refinement.

  7. High frequency flow-structural interaction in dense subsonic fluids

    NASA Technical Reports Server (NTRS)

    Liu, Baw-Lin; Ofarrell, J. M.

    1995-01-01

    Prediction of the detailed dynamic behavior in rocket propellant feed systems and engines and other such high-energy fluid systems requires precise analysis to assure structural performance. Designs sometimes require placement of bluff bodies in a flow passage. Additionally, there are flexibilities in ducts, liners, and piping systems. A design handbook and interactive data base have been developed for assessing flow/structural interactions to be used as a tool in design and development, to evaluate applicable geometries before problems develop, or to eliminate or minimize problems with existing hardware. This is a compilation of analytical/empirical data and techniques to evaluate detailed dynamic characteristics of both the fluid and structures. These techniques have direct applicability to rocket engine internal flow passages, hot gas drive systems, and vehicle propellant feed systems. Organization of the handbook is by basic geometries for estimating Strouhal numbers, added mass effects, mode shapes for various end constraints, critical onset flow conditions, and possible structural response amplitudes. Emphasis is on dense fluids and high structural loading potential for fatigue at low subsonic flow speeds where high-frequency excitations are possible. Avoidance and corrective measure illustrations are presented together with analytical curve fits for predictions compiled from a comprehensive data base.

  8. Supersonic Jet Exhaust Noise at High Subsonic Flight Speed

    NASA Technical Reports Server (NTRS)

    Norum, Thomas D.; Garber, Donald P.; Golub, Robert A.; Santa Maria, Odilyn L.; Orme, John S.

    2004-01-01

    An empirical model to predict the effects of flight on the noise from a supersonic transport is developed. This model is based on an analysis of the exhaust jet noise from high subsonic flights of the F-15 ACTIVE Aircraft. Acoustic comparisons previously attainable only in a wind tunnel were accomplished through the control of both flight operations and exhaust nozzle exit diameter. Independent parametric variations of both flight and exhaust jet Mach numbers at given supersonic nozzle pressure ratios enabled excellent correlations to be made for both jet broadband shock noise and jet mixing noise at flight speeds up to Mach 0.8. Shock noise correlated with flight speed and emission angle through a Doppler factor exponent of about 2.6. Mixing noise at all downstream angles was found to correlate well with a jet relative velocity exponent of about 7.3, with deviations from this behavior only at supersonic eddy convection speeds and at very high flight Mach numbers. The acoustic database from the flight test is also provided.

  9. Coherent structures and wavepackets in subsonic transitional turbulent jets

    NASA Astrophysics Data System (ADS)

    Yang, Haihua; Zhang, Xingchen; Ran, Lingke; Sun, Dejun; Wan, Zhenhua

    2017-02-01

    A large eddy simulation (LES) is performed for two subsonic jets with a Reynolds number of Re=10^5, which have different core temperatures, i.e., the cold and hot jet. The far-field overall sound pressure levels (OASPL) and noise spectra are well validated against previous experimental results. It is found that the OASPL is raised by heating at shallow angles. The most energetic coherent structures are extracted with specified frequencies using the filter based on the frequency domain variant of the snapshot method of proper orthogonal decomposition (POD). The m=0,1 modes have high coherence of near-field pressure for both jets, while the coherence of m=0 modes is enhanced greatly by heating. Based on the coherent structures, spatial wavepackets are educed and the characteristics of growth, saturation and decay are analyzed and compared between the two jets in detail. The results show that heating would enhance the linear growth rate for high frequency components, and nonlinear growth rates for low frequency components in general, which are responsible for higher OASPL in the hot jet. The far-field sound generated by wavepackets is computed using the Kirchhoff extrapolation, which matches well with that of LES at shallow angles. This indicates that the wavepackets associated with coherent structures are dominant sound sources in forced transitional turbulent jets. Additionally, the present POD method is proven to be a robust tool to extract the salient features of the wavepackets in turbulent flows.

  10. Computational Study of Separating Flow in a Planar Subsonic Diffuser

    NASA Technical Reports Server (NTRS)

    DalBello, Teryn; Dippold, Vance, III; Georgiadis, Nicholas J.

    2005-01-01

    A computational study of the separated flow through a 2-D asymmetric subsonic diffuser has been performed. The Wind Computational Fluid Dynamics code is used to predict the separation and reattachment behavior for an incompressible diffuser flow. The diffuser inlet flow is a two-dimensional, turbulent, and fully-developed channel flow with a Reynolds number of 20,000 based on the centerline velocity and the channel height. Wind solutions computed with the Menter SST, Chien k-epsilon, Spalart-Allmaras and Explicit Algebraic Reynolds Stress turbulence models are compared with experimentally measured velocity profiles and skin friction along the upper and lower walls. In addition to the turbulence model study, the effects of grid resolution and use of wall functions were investigated. The grid studies varied the number of grid points across the diffuser and varied the initial wall spacing from y(sup +) = 0.2 to 60. The wall function study assessed the applicability of wall functions for analysis of separated flow. The SST and Explicit Algebraic Stress models provide the best agreement with experimental data, and it is recommended wall functions should only be used with a high level of caution.

  11. Chaos control for the plates subjected to subsonic flow

    NASA Astrophysics Data System (ADS)

    Norouzi, Hamed; Younesian, Davood

    2016-07-01

    The suppression of chaotic motion in viscoelastic plates driven by external subsonic air flow is studied. Nonlinear oscillation of the plate is modeled by the von-Kármán plate theory. The fluid-solid interaction is taken into account. Galerkin's approach is employed to transform the partial differential equations of the system into the time domain. The corresponding homoclinic orbits of the unperturbed Hamiltonian system are obtained. In order to study the chaotic behavior of the plate, Melnikov's integral is analytically applied and the threshold of the excitation amplitude and frequency for the occurrence of chaos is presented. It is found that adding a parametric perturbation to the system in terms of an excitation with the same frequency of the external force can lead to eliminate chaos. Variations of the Lyapunov exponent and bifurcation diagrams are provided to analyze the chaotic and periodic responses. Two perturbation-based control strategies are proposed. In the first scenario, the amplitude of control forces reads a constant value that should be precisely determined. In the second strategy, this amplitude can be proportional to the deflection of the plate. The performance of each controller is investigated and it is found that the second scenario would be more efficient.

  12. Hot-wire calibration in subsonic/transonic flow regimes

    NASA Technical Reports Server (NTRS)

    Nagabushana, K. A.; Ash, Robert L.

    1995-01-01

    A different approach for calibrating hot-wires, which simplifies the calibration procedure and reduces the tunnel run-time by an order of magnitude was sought. In general, it is accepted that the directly measurable quantities in any flow are velocity, density, and total temperature. Very few facilities have the capability of varying the total temperature over an adequate range. However, if the overheat temperature parameter, a(sub w), is used to calibrate the hot-wire then the directly measurable quantity, voltage, will be a function of the flow variables and the overheat parameter i.e., E = f(u,p,a(sub w), T(sub w)) where a(sub w) will contain the needed total temperature information. In this report, various methods of evaluating sensitivities with different dependent and independent variables to calibrate a 3-Wire hot-wire probe using a constant temperature anemometer (CTA) in subsonic/transonic flow regimes is presented. The advantage of using a(sub w) as the independent variable instead of total temperature, t(sub o), or overheat temperature parameter, tau, is that while running a calibration test it is not necessary to know the recovery factor, the coefficients in a wire resistance to temperature relationship for a given probe. It was deduced that the method employing the relationship E = f (u,p,a(sub w)) should result in the most accurate calibration of hot wire probes. Any other method would require additional measurements. Also this method will allow calibration and determination of accurate temperature fluctuation information even in atmospheric wind tunnels where there is no ability to obtain any temperature sensitivity information at present. This technique greatly simplifies the calibration process for hot-wires, provides the required calibration information needed in obtaining temperature fluctuations, and reduces both the tunnel run-time and the test matrix required to calibrate hotwires. Some of the results using the above techniques are presented

  13. Computational Investigations of Noise Suppression in Subsonic Round Jets

    NASA Technical Reports Server (NTRS)

    Pruett, C. David

    1997-01-01

    NASA Grant NAG1-1802, originally submitted in June 1996 as a two-year proposal, was awarded one-year's funding by NASA LaRC for the period 5 Oct., 1996, through 4 Oct., 1997. Because of the inavailability (from IT at NASA ARC) of sufficient supercomputer time in fiscal 1998 to complete the computational goals of the second year of the original proposal (estimated to be at least 400 Cray C-90 CPU hours), those goals have been appropriately amended, and a new proposal has been submitted to LaRC as a follow-on to NAG1-1802. The current report documents the activities and accomplishments on NAG1-1802 during the one-year period from 5 Oct., 1996, through 4 Oct., 1997. NASA Grant NAG1-1802, and its predecessor, NAG1-1772, have been directed toward adapting the numerical tool of Large-Eddy Simulation (LES) to aeroacoustic applications, with particular focus on noise suppression in subsonic round jets. In LES, the filtered Navier-Stokes equations are solved numerically on a relatively coarse computational grid. Residual stresses, generated by scales of motion too small to be resolved on the coarse grid, are modeled. Although most LES incorporate spatial filtering, time-domain filtering affords certain conceptual and computational advantages, particularly for aeroacoustic applications. Consequently, this work has focused on the development of SubGrid-Scale (SGS) models that incorporate time- domain filters. The author is unaware of any previous attempt at purely time-filtered LES; however, Aldama and Dakhoul and Bedford have considered approaches that combine both spatial and temporal filtering. In our view, filtering in both space and time is redundant, because removal of high frequencies effects the removal of small spatial scales and vice versa.

  14. NASA technology program for future civil air transports

    NASA Technical Reports Server (NTRS)

    Wright, H. T.

    1983-01-01

    An assessment is undertaken of the development status of technology, applicable to future civil air transport design, which is currently undergoing conceptual study or testing at NASA facilities. The NASA civil air transport effort emphasizes advanced aerodynamic computational capabilities, fuel-efficient engines, advanced turboprops, composite primary structure materials, advanced aerodynamic concepts in boundary layer laminarization and aircraft configuration, refined control, guidance and flight management systems, and the integration of all these design elements into optimal systems. Attention is given to such novel transport aircraft design concepts as forward swept wings, twin fuselages, sandwich composite structures, and swept blade propfans.

  15. Classification of extraterrestrial civilizations

    NASA Astrophysics Data System (ADS)

    Tang, Tong B.; Chang, Grace

    1991-06-01

    A scheme of classification of extraterrestrial intelligence (ETI) communities based on the scope of energy accessible to the civilization in question is proposed as an alternative to the Kardeshev (1964) scheme that includes three types of civilization, as determined by their levels of energy expenditure. The proposed scheme includes six classes: (1) a civilization that runs essentially on energy exerted by individual beings or by domesticated lower life forms, (2) harnessing of natural sources on planetary surface with artificial constructions, like water wheels and wind sails, (3) energy from fossils and fissionable isotopes, mined beneath the planet surface, (4) exploitation of nuclear fusion on a large scale, whether on the planet, in space, or from primary solar energy, (5) extensive use of antimatter for energy storage, and (6) energy from spacetime, perhaps via the action of naked singularities.

  16. Investigation of a subsonic-arc-attachment thruster using segmented anodes

    NASA Technical Reports Server (NTRS)

    Berns, Darren H.; Sankovic, John M.; Sarmiento, Charles J.

    1993-01-01

    To investigate high frequency arc instabilities observed in subsonic-arc-attachment thrusters, a 3 kW, segmented-anode arc jet was designed and tested using hydrogen as the propellant. The thruster nozzle geometry was scaled from a 30 kW design previously tested in the 1960's. By observing the current to each segment and the arc voltage, it was determined that the 75-200 kHz instabilities were results of axial movements of the arc anode attachment point. The arc attachment point was fully contained in the subsonic portion of the nozzle for nearly all flow rates. The effects of isolating selected segments were investigated. In some cases, forcing the arc downstream caused the restrike to cease. Finally, decreasing the background pressure from 18 to 0.05 Pa affected the pressure distribution in the nozzle including the pressure in the subsonic arc chamber.

  17. Investigation of a subsonic-arc-attachment thruster using segmented anodes

    NASA Astrophysics Data System (ADS)

    Berns, Darren H.; Sankovic, John M.; Sarmiento, Charles J.

    1993-12-01

    To investigate high frequency arc instabilities observed in subsonic-arc-attachment thrusters, a 3 kW, segmented-anode arc jet was designed and tested using hydrogen as the propellant. The thruster nozzle geometry was scaled from a 30 kW design previously tested in the 1960's. By observing the current to each segment and the arc voltage, it was determined that the 75-200 kHz instabilities were results of axial movements of the arc anode attachment point. The arc attachment point was fully contained in the subsonic portion of the nozzle for nearly all flow rates. The effects of isolating selected segments were investigated. In some cases, forcing the arc downstream caused the restrike to cease. Finally, decreasing the background pressure from 18 to 0.05 Pa affected the pressure distribution in the nozzle including the pressure in the subsonic arc chamber.

  18. Creative Ventures: Ancient Civilizations.

    ERIC Educational Resources Information Center

    Stark, Rebecca

    The open-ended activities in this book are designed to extend the imagination and creativity of students and encourage students to examine their feelings and values about historic eras. Civilizations addressed include ancient Egypt, Greece, Rome, Mayan, Stonehenge, and Mesopotamia. The activities focus upon the cognitive and affective pupil…

  19. European Civilization. Teacher's Manual.

    ERIC Educational Resources Information Center

    Leppert, Ella C.; Halac, Dennis

    The instructional materials in this teaching guide for Course II, Unit IV, follow and build upon a previous sequential course described in SO 003 169 offering ninth grade students a study on the development of Western European Civilization. Focus is upon four periods of high development: The High Middle Ages (12th Century), The Renaissance (15th…

  20. History and Undergraduate Civilization.

    ERIC Educational Resources Information Center

    Conroy, Peter

    1995-01-01

    It is argued that a traditional, historically-oriented course in 17th- and 18th-century French civilization continues to be an appropriate and effective approach for undergraduate French study, in preparation for later, more sophisticated cultural analysis. Four course components are discussed: class lectures; literary text selection; textbook…

  1. Righting Civil Wrongs.

    ERIC Educational Resources Information Center

    Murrell, Dan S.; And Others

    1992-01-01

    The 1991 Civil Rights Act fills many gaps in existing employment laws, but its implications for higher education go beyond employment to admissions and students affairs. Trustees should direct administrators to review personnel policies and practices and liability insurance coverage in light of the new law. (Author/MSE)

  2. Civil Law: 12 Activities.

    ERIC Educational Resources Information Center

    Dresbach, Debra

    These learning activities on civil law are intended to supplement the secondary level Scholastic materials "Living Law." Case studies, simulations, and role-play activities are included. Information provided for each activity includes a brief overview, background information, teacher instructions and a description of each activity.…

  3. Criminal Acts Against Civil Aviation

    DTIC Science & Technology

    1991-01-01

    28 Soviet Union ...34 Feature Articles Civil Aviation in the Soviet Union ................................................................. 39 Attacks on Airline...relief transport aircraft or hijackings; none were related to the Gulf war. Likewise, in Asia, there were few criminal acts against civil aviation

  4. Civil partnerships five years on.

    PubMed

    Ross, Helen; Gask, Karen; Berrington, Ann

    2011-01-01

    The Civil Partnership Act 2004, which came into force in December 2005 allowing same-sex couples in the UK to register their relationship for the first time, celebrated its fifth anniversary in December 2010. This article examines civil partnership in England and Wales, five years on from its introduction. The characteristics of those forming civil partnerships between 2005 and 2010 including age, sex and previous marital/civil partnership status are examined. These are then compared with the characteristics of those marrying over the same period. Further comparisons are also made between civil partnership dissolutions and divorce. The article presents estimates of the number of people currently in civil partnerships and children of civil partners. Finally the article examines attitudes towards same-sex and civil partner couples both in the UK and in other countries across Europe.

  5. Subsonic Cascade Wind Tunnel Tests Using a Compressor Configuration of DCA Blades.

    DTIC Science & Technology

    1981-06-01

    1399 - .257 1 4 -I,. ’- 𔃾 1 4 4930 1432 -. 1653 15:;7 .5669 1412 -. 1295 - 7746407 13.3𔄃a 0 5-3,’ 175139 -. 8 , .. 7 4 * ,r I t - 7146 .1289 . 0833 ...EDoNa OF I NOV 61 IS OBSOLETE (Page 1 ) s’w4 0 10 2-014- 6601 r1NCT.AA.9T~’TE S SECURITY CLASSIFICATION OF THIS PAGE (She..n DotaEnter*ed) UNCLASSIFIED...6 LIST OF FIGURES Figure 1 . Subsonic Cascade Facility ------------------------ 43 2. Photograph of Subsonic Cascade and Test Section -- 44 3

  6. The Liquid Hydrogen Option for the Subsonic Transport: A status report

    NASA Technical Reports Server (NTRS)

    Korycinski, P. F.

    1977-01-01

    Continued subsonic air transport design studies include the option for a liquid hydrogen fuel system as an aircraft fuel conservation measure. Elements of this option discussed include: (1) economical production of hydrogen; (2) efficient liquefaction of hydrogen; (3) materials for long service life LH2 fuel tanks; (4) insulation materials; (5) LH2 fuel service and installations at major air terminals; (6) assessment of LH2 hazards; and (7) the engineering definition of an LH2 fuel system for a large subsonic passenger air transport.

  7. CFD-Based Design Optimization Tool Developed for Subsonic Inlet

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The traditional approach to the design of engine inlets for commercial transport aircraft is a tedious process that ends with a less-than-optimum design. With the advent of high-speed computers and the availability of more accurate and reliable computational fluid dynamics (CFD) solvers, numerical optimization processes can effectively be used to design an aerodynamic inlet lip that enhances engine performance. The designers' experience at Boeing Corporation showed that for a peak Mach number on the inlet surface beyond some upper limit, the performance of the engine degrades excessively. Thus, our objective was to optimize efficiency (minimize the peak Mach number) at maximum cruise without compromising performance at other operating conditions. Using a CFD code NPARC, the NASA Lewis Research Center, in collaboration with Boeing, developed an integrated procedure at Lewis to find the optimum shape of a subsonic inlet lip and a numerical optimization code, ADS. We used a GRAPE-based three-dimensional grid generator to help automate the optimization procedure. The inlet lip shape at the crown and the keel was described as a superellipse, and the superellipse exponents and radii ratios were considered as design variables. Three operating conditions: cruise, takeoff, and rolling takeoff, were considered in this study. Three-dimensional Euler computations were carried out to obtain the flow field. At the initial design, the peak Mach numbers for maximum cruise, takeoff, and rolling takeoff conditions were 0.88, 1.772, and 1.61, respectively. The acceptable upper limits on the takeoff and rolling takeoff Mach numbers were 1.55 and 1.45. Since the initial design provided by Boeing was found to be optimum with respect to the maximum cruise condition, the sum of the peak Mach numbers at takeoff and rolling takeoff were minimized in the current study while the maximum cruise Mach number was constrained to be close to that at the existing design. With this objective, the

  8. Design Study of Propulsion and Drive Systems for the Large Civil TiltRotor (LCTR2) Rotorcraft

    NASA Technical Reports Server (NTRS)

    Robuck, Mark; Wilkerson, Joseph; Zhang, Yiyi; Snyder, Christopher A.; Vonderwell, Daniel

    2013-01-01

    Boeing, Rolls Royce, and NASA have worked together to complete a parametric sizing study for NASA's Large Civil Tilt Rotor (LCTR2) concept 2nd iteration. Vehicle gross weight and fuel usage were evaluated as propulsion and drive system characteristics were varied to maximize the benefit of reduced rotor tip speed during cruise conditions. The study examined different combinations of engine and gearbox variability to achieve rotor cruise tip speed reductions down to 54% of the hover tip speed. Previous NASA studies identified that a 54% rotor speed reduction in cruise minimizes vehicle gross weight and fuel burn. The LCTR2 was the study baseline for initial sizing. This study included rotor tip speed ratios (cruise to hover) of 100%, 77% and 54% at different combinations of engine RPM and gearbox speed reductions, which were analyzed to achieve the lightest overall vehicle gross weight (GW) at the chosen rotor tip speed ratio. Different engine and gearbox technology levels are applied ranging from commercial off-the-shelf (COTS) engines and gearbox technology to entry-in-service (EIS) dates of 2025 and 2035 to assess the benefits of advanced technology on vehicle gross weight and fuel burn. Interim results were previously reported1. This technical paper extends that work and summarizes the final study results including additional engine and drive system study accomplishments. New vehicle sizing data is presented for engine performance at a single operating speed with a multispeed drive system. Modeling details for LCTR2 vehicle sizing and subject engine and drive sub-systems are presented as well. This study was conducted in support of NASA's Fundamental Aeronautics Program, Subsonic Rotary Wing Project.

  9. Joint Doctrine for Civil Affairs

    DTIC Science & Technology

    2007-11-02

    Authorities ( MACA ), DODD 5525.5, DOD Cooperation with Civilian Law Enforcement Officials, and JP 3-07.7, Joint Doctrine for Civil Support. II-15 Civil Affairs...Joint Operation Planning and Execution System JP joint publication JTF joint task force LOAC law of armed conflict MACA military assistance to civil

  10. Civility in Classes and Sports

    ERIC Educational Resources Information Center

    Lumpkin, Angela

    2010-01-01

    Civility is a polite or courteous act, expression, or standard of conduct, including the display of respect and tolerance to everyone. Teaching and modeling civility in classes and with sport teams is essential so students and athletes can learn the importance of and demonstrate civility in their interactions with others. Teachers and coaches…

  11. Subsonic and supersonic indicial aerodynamics and aerodynamic transfer function for complex configurations. [aerodynamic configurations for subsonic and supersonic speeds using the finite element method

    NASA Technical Reports Server (NTRS)

    Morino, L.

    1974-01-01

    A general theory for indicial-potential-compressible aerodynamics around complex configurations is presented. The motion is assumed to consist of constant subsonic or supersonic speed (steady state) and small perturbations around the steady state. Using the finite-element method to discretize the space problem, a set of differential-difference equations in time relating the potential to its normal derivative on the surface of the body was obtained. The aerodynamics transfer function was derived by using standard method of operational calculus.

  12. Cyber threats within civil aviation

    NASA Astrophysics Data System (ADS)

    Heitner, Kerri A.

    Existing security policies in civil aviation do not adequately protect against evolving cyber threats. Cybersecurity has been recognized as a top priority among some aviation industry leaders. Heightened concerns regarding cyber threats and vulnerabilities surround components utilized in compliance with the Federal Aviation Administration's (FAA) Next Generation Air Transportation (NextGen) implementation. Automated Dependent Surveillance-B (ADS-B) and Electronic Flight Bags (EFB) have both been exploited through the research of experienced computer security professionals. Civil aviation is essential to international infrastructure and if its critical assets were compromised, it could pose a great risk to public safety and financial infrastructure. The purpose of this research was to raise awareness of aircraft system vulnerabilities in order to provoke change among current national and international cybersecurity policies, procedures and standards. Although the education of cyber threats is increasing in the aviation industry, there is not enough urgency when creating cybersecurity policies. This project intended to answer the following questions: What are the cyber threats to ADS-B of an aircraft in-flight? What are the cyber threats to EFB? What is the aviation industry's response to the issue of cybersecurity and in-flight safety? ADS-B remains unencrypted while the FAA's mandate to implement this system is rapidly approaching. The cyber threat of both portable and non-portable EFB's have received increased publicity, however, airlines are not responding quick enough (if at all) to create policies for the use of these devices. Collectively, the aviation industry is not being proactive enough to protect its aircraft or airport network systems. That is not to say there are not leaders in cybersecurity advancement. These proactive organizations must set the standard for the future to better protect society and it's most reliable form of transportation.

  13. Galactic-scale civilization

    NASA Technical Reports Server (NTRS)

    Kuiper, T. B. H.

    1980-01-01

    Evolutionary arguments are presented in favor of the existence of civilization on a galactic scale. Patterns of physical, chemical, biological, social and cultural evolution leading to increasing levels of complexity are pointed out and explained thermodynamically in terms of the maximization of free energy dissipation in the environment of the organized system. The possibility of the evolution of a global and then a galactic human civilization is considered, and probabilities that the galaxy is presently in its colonization state and that life could have evolved to its present state on earth are discussed. Fermi's paradox of the absence of extraterrestrials in light of the probability of their existence is noted, and a variety of possible explanations is indicated. Finally, it is argued that although mankind may be the first occurrence of intelligence in the galaxy, it is unjustified to presume that this is so.

  14. Civil War vascular injuries.

    PubMed

    Blaisdell, F William

    2005-01-01

    As the result of the insistence of the Surgeon General during the United States Civil War, there was extensive documentation of injuries to major blood vessels and their resulting complications. The specific treatment of vascular injuries during the Civil War was ligation of the injured vessel or amputation. This was before there was any knowledge of the cause and prevention of infection. Overall, the results were dismal, with a mortality rate of nearly 60% for the more than 1000 soldiers treated by arterial ligation. The most important contribution of these medical reports was to define how the injuries should be diagnosed and managed. Many of the principles that developed as the result of this post-war review are as valid today as they were then. Unfortunately, it seems that many of these lessons have had to be relearned by the surgeons who have participated in each of our subsequent military conflicts.

  15. NASTRAN documentation for flutter analysis of advanced turbopropellers

    NASA Technical Reports Server (NTRS)

    Elchuri, V.; Gallo, A. M.; Skalski, S. C.

    1982-01-01

    An existing capability developed to conduct modal flutter analysis of tuned bladed-shrouded discs was modified to facilitate investigation of the subsonic unstalled flutter characteristics of advanced turbopropellers. The modifications pertain to the inclusion of oscillatory modal aerodynamic loads of blades with large (backward and forward) varying sweep.

  16. Data Reduction Functions for the Langley 14- by 22-Foot Subsonic Tunnel

    NASA Technical Reports Server (NTRS)

    Boney, Andy D.

    2014-01-01

    The Langley 14- by 22-Foot Subsonic Tunnel's data reduction software utilizes six major functions to compute the acquired data. These functions calculate engineering units, tunnel parameters, flowmeters, jet exhaust measurements, balance loads/model attitudes, and model /wall pressures. The input (required) variables, the output (computed) variables, and the equations and/or subfunction(s) associated with each major function are discussed.

  17. 12. SOUTHWEST VIEW OF BUILDING 25C (SUBSONIC AERODYNAMICS TEST FACILITY) ...

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

    12. SOUTHWEST VIEW OF BUILDING 25C (SUBSONIC AERODYNAMICS TEST FACILITY) (1992). - Wright-Patterson Air Force Base, Area B, Buildings 25 & 24,10-foot & 20-foot Wind Tunnel Complex, Northeast side of block bounded by K, G, Third, & Fifth Streets, Dayton, Montgomery County, OH

  18. Wing-Alone Aerodynamic Characteristics to High Angles of Attack at Subsonic and Transonic Speeds.

    DTIC Science & Technology

    1982-11-01

    indicators of symmetry since the wings were unbanked within the limits of tolerances and flow angularity. Longitudinal, spanwise, and vertical... unbanked wings at subsonic and transonic speeds from low to high angles of attack. The wing planforms varied in aspect ratio and taper ratio with

  19. Computer program calculates peripheral water injection cooling of axisymmetric subsonic diffuser

    NASA Technical Reports Server (NTRS)

    Grey, J.

    1968-01-01

    Digital computer program calculates the cooling effectiveness and flow characteristics resulting from the mixing of a cool liquid injectant /water/ with a hot sonic or subsonic gas stream /hydrogen/. The output of the program provides pressure, temperature, velocity, density, composition, and Mach number profiles at any location in the mixing duct.

  20. On the circulatory subsonic flow of a compressible fluid past a circular cylinder

    NASA Technical Reports Server (NTRS)

    Bers, Lipman

    1945-01-01

    The circulatory subsonic flow around an infinite circular cylinder is computed using the linearized pressure-volume relation, by a method developed in a previous report. Formulas and graphs are given for the velocity and pressure distributions, the circulation, the lift, and the dependence of the critical Mach number upon the position of the stagnation point.

  1. Pressure Distributions About Finite Wedges in Bounded and Unbounded Subsonic Streams

    NASA Technical Reports Server (NTRS)

    Donoughe, Patrick L; Prasse, Ernst I

    1953-01-01

    An analytical investigation of incompressible flow about wedges was made to determine effects of tunnel-wedge ratio and wedge angle on the wedge pressure distributions. The region of applicability of infinite wedge-type velocity distribution was examined for finite wedges. Theoretical and experimental pressure coefficients for various tunnel-wedge ratios, wedge angles, and subsonic Mach numbers were compared.

  2. Method of Making a Composite Panel Having Subsonic Transverse Wave Speed Characteristics

    NASA Technical Reports Server (NTRS)

    Palumbo, Daniel L. (Inventor); Klos, Jacob (Inventor)

    2012-01-01

    A method of making a composite panel having subsonic transverse wave speed characteristics which has first and second sheets sandwiching a core with at least one of the sheets being attached to the core at first regions thereof and unattached to the core at second regions thereof.

  3. X-24A Detailing Subsonic Control Surface Configuration

    NASA Technical Reports Server (NTRS)

    1971-01-01

    This annotated photo shows a rear view of the X-24A lifting body research vehicle, emphasizing the control surfaces used for the subsonic portions of the aircraft's flights. The X-24 was one of a group of lifting bodies flown by the NASA Flight Research Center (now Dryden Flight Research Center), Edwards, California, in a joint program with the U.S. Air Force at Edwards Air Force Base from 1963 to 1975. The lifting bodies were used to demonstrate the ability of pilots to maneuver and safely land wingless vehicles designed to fly back to Earth from space and be landed like an airplane at a predetermined site. Lifting bodies' aerodynamic lift, essential to flight in the atmosphere, was obtained from their shape. The addition of fins and control surfaces allowed the pilots to stabilize and control the vehicles and regulate their flight paths. Built by Martin Aircraft Company, Maryland, for the U.S. Air Force, the X-24A was a bulbous vehicle shaped like a teardrop with three vertical fins at the rear for directional control. It weighed 6,270 pounds, was 24.5 feet long and 11.5 feet wide (measuring just the fuselage, not the distance between the tips of the outboard fins). Its first unpowered glide flight was on April 17, 1969, with Air Force Maj. Jerauld Gentry at the controls. Gentry also piloted its first powered flight on March 19, 1970. The X-24A was flown 28 times in the program that, like the HL-10, validated the concept that a Space Shuttle vehicle could be landed unpowered. The fastest speed achieved by the X-24A was 1,036 miles per hour (mph--Mach 1.6). Its maximum altitude was 71,400 feet. It was powered by an XLR-11 rocket engine with a maximum theoretical vacuum thrust of 8,480 pounds. The X-24A was later modified into the X-24B. The bulbous shape of the X-24A was converted into a 'flying flatiron' shape with a rounded top, flat bottom, and double delta platform that ended in a pointed nose. The X-24B demonstrated that accurate unpowered reentry vehicle

  4. Low-Speed Stability-and-Control and Ground-Effects Measurements on the Industry Reference High Speed Civil Transport

    NASA Technical Reports Server (NTRS)

    Kemmerly, Guy T.; Campbell, Bryan A.; Banks, Daniel W.; Yaros, Steven F.

    1999-01-01

    As a part of a national effort to develop an economically feasible High Speed Civil Transport (HSCT), a single configuration has been accepted as the testing baseline by the organizations working in the High Speed Research (HSR) program. The configuration is based on a design developed by the Boeing Company and is referred to as the Reference H (Ref H). The data contained in this report are low-speed stability-and-control and ground-effect measurements obtained on a 0.06 scale model of the Ref H in a subsonic tunnel.

  5. On the Importance of Very Light Internally Subsonic AGN Jets in Radio-mode AGN Feedback

    NASA Astrophysics Data System (ADS)

    Guo, Fulai

    2016-07-01

    Radio-mode active galactic nucleus (AGN) feedback plays a key role in the evolution of galaxy groups and clusters. Its physical origin lies in the kiloparsec-scale interaction of AGN jets with the intracluster medium. Large-scale jet simulations often initiate light internally supersonic jets with density contrast 0.01 < η < 1. Here we argue for the first time for the importance of very light (η < 0.01) internally subsonic jets. We investigated the shapes of young X-ray cavities produced in a suite of hydrodynamic simulations, and found that bottom-wide cavities are always produced by internally subsonic jets, while internally supersonic jets inflate cylindrical, center-wide, or top-wide cavities. We found examples of real cavities with shapes analogous to those inflated in our simulations by internally subsonic and internally supersonic jets, suggesting a dichotomy of AGN jets according to their internal Mach numbers. We further studied the long-term cavity evolution, and found that old cavities resulted from light jets spread along the jet direction, while those produced by very light jets are significantly elongated along the perpendicular direction. The northwestern ghost cavity in Perseus is pancake shaped, providing tentative evidence for the existence of very light jets. Our simulations show that very light internally subsonic jets decelerate faster and rise much slower in the intracluster medium than light internally supersonic jets, possibly depositing a larger fraction of jet energy to cluster cores and alleviating the problem of low coupling efficiencies found previously. The internal Mach number points to the jet’s energy content, and internally subsonic jets are energetically dominated by non-kinetic energy, such as thermal energy, cosmic rays, or magnetic fields.

  6. Advanced subsonic long-haul transport terminal area compatibility study. Volume 2: Research and technology recommendations

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The Terminal Area Compatibility (TAC) study is briefly summarized for background information. The most important research items for the areas of noise congestion, and emissions are identified. Other key research areas are also discussed. The 50 recommended research items are categorized by flight phase, technology, and compatibility benefits. The relationship of the TAC recommendations to the previous ATT recommendations is discussed. The bulk of the document contains the 50 recommended research items. For each item, the potential payoff, state of readiness, recommended action and estimated cost and schedule are given.

  7. Advanced Subsonic Technology (AST) Area of Interest (AOI) 6: Develop and Validate Aeroelastic Codes for Turbomachinery

    NASA Technical Reports Server (NTRS)

    Gardner, Kevin D.; Liu, Jong-Shang; Murthy, Durbha V.; Kruse, Marlin J.; James, Darrell

    1999-01-01

    AlliedSignal Engines, in cooperation with NASA GRC (National Aeronautics and Space Administration Glenn Research Center), completed an evaluation of recently-developed aeroelastic computer codes using test cases from the AlliedSignal Engines fan blisk and turbine databases. Test data included strain gage, performance, and steady-state pressure information obtained for conditions where synchronous or flutter vibratory conditions were found to occur. Aeroelastic codes evaluated included quasi 3-D UNSFLO (MIT Developed/AE Modified, Quasi 3-D Aeroelastic Computer Code), 2-D FREPS (NASA-Developed Forced Response Prediction System Aeroelastic Computer Code), and 3-D TURBO-AE (NASA/Mississippi State University Developed 3-D Aeroelastic Computer Code). Unsteady pressure predictions for the turbine test case were used to evaluate the forced response prediction capabilities of each of the three aeroelastic codes. Additionally, one of the fan flutter cases was evaluated using TURBO-AE. The UNSFLO and FREPS evaluation predictions showed good agreement with the experimental test data trends, but quantitative improvements are needed. UNSFLO over-predicted turbine blade response reductions, while FREPS under-predicted them. The inviscid TURBO-AE turbine analysis predicted no discernible blade response reduction, indicating the necessity of including viscous effects for this test case. For the TURBO-AE fan blisk test case, significant effort was expended getting the viscous version of the code to give converged steady flow solutions for the transonic flow conditions. Once converged, the steady solutions provided an excellent match with test data and the calibrated DAWES (AlliedSignal 3-D Viscous Steady Flow CFD Solver). However, efforts expended establishing quality steady-state solutions prevented exercising the unsteady portion of the TURBO-AE code during the present program. AlliedSignal recommends that unsteady pressure measurement data be obtained for both test cases examined for use in aeroelastic code validation.

  8. Minimum Climb to Cruise Noise Trajectories Modeled for the High Speed Civil Transport

    NASA Technical Reports Server (NTRS)

    Berton, Jeffrey J.

    1998-01-01

    The proposed U.S. High Speed Civil Transport (HSCT) will revolutionize commercial air travel by providing economical supersonic passenger service to destinations worldwide. Unlike the high-bypass turbofan engines that propel today's subsonic airliners, HSCT engines will have much higher jet exhaust speeds. Jet noise, caused by the turbulent mixing of high-speed exhaust with the surrounding air, poses a significant challenge for HSCT engine designers. To resolve this challenge, engineers have designed advanced mixer rejector nozzles that reduce HSCT jet noise to airport noise certification levels by entraining and mixing large quantities of ambient air with the engines' jet streams. Although this works well during the first several minutes of flight, far away from the airport, as the HSCT gains speed and climbs, poor ejector inlet recovery and ejector ram drag contribute to poor thrust, making it advantageous to turn off the ejector. Doing so prematurely, however, can cause unacceptable noise levels to propagate to the ground, even when the aircraft is many miles from the airport. This situation lends itself ideally to optimization, where the aircraft trajectory, throttle setting, and ejector setting can be varied (subject to practical aircraft constraints) to minimize the noise propagated to the ground. A method was developed at the NASA Lewis Research Center that employs a variation of the classic energy state approximation: a trajectory analysis technique historically used to minimize climb time or fuel burned in many aircraft problems. To minimize the noise on the ground at any given throttle setting, high aircraft altitudes are desirable; but the HSCT may either climb quickly to high altitudes using a high, noisy throttle setting or climb more slowly at a lower, quieter throttle setting. An optimizer has been programmed into NASA's existing aircraft and noise analysis codes to balance these options by dynamically choosing the best altitude-velocity path and

  9. Experimental Pressure Distributions over Wing Tips at Mach Number 1.9 I : Wing Tip with Subsonic Leading Edge

    NASA Technical Reports Server (NTRS)

    Jagger, James M; Mirels, Harold

    1949-01-01

    An investigation was conducted at a Mach number of 1.91 to determine spanwise pressure distribution over a wing tip in a region influenced by a sharp subsonic leading edge swept back at 70 degrees. Except for pressure distribution on the top surface in the immediate vicinity of the subsonic leading edge, the maximum difference between linearized theory and experimental data was 2 1/2 percent (of free-stream dynamic pressure) for angles of attack up to 4 degrees and 7 percent for angles of attack up to 8 degrees. Pressures on the top surface nearest the subsonic edge indicated local expansions beyond values predicted by linearized theory.

  10. Nine for Equality Under Law: Civil Rights Litigation. A Report to the Ford Foundation

    ERIC Educational Resources Information Center

    McKay, Robert B.

    This report reviews the litigation activities of the nine organizations which received financial assistance from the Ford Foundation to assess the usefulness of litigation as a means of advancing Constitutional civil rights. The litigation activities of the NAACP Legal Defense and Educational Fund, and the Lawyers' Committee for Civil Rights Under…

  11. The Impact of the Civil Rights Movement on the Women's Movement.

    ERIC Educational Resources Information Center

    O'Connor, Karen

    1988-01-01

    States that the civil rights movements served as a catalyst to women in working for their own rights. Points out that the American Civil Liberties Union (ACLU) Women's Rights Project, modeled after the National Association for the Advancement of Colored People (NAACP) Legal Defense fund, led the litigation battles for women's rights. Lists…

  12. Acoustic Data Processing and Transient Signal Analysis for the Hybrid Wing Body 14- by 22-Foot Subsonic Wind Tunnel Test

    NASA Technical Reports Server (NTRS)

    Bahr, Christopher J.; Brooks, Thomas F.; Humphreys, William M.; Spalt, Taylor B.; Stead, Daniel J.

    2014-01-01

    An advanced vehicle concept, the HWB N2A-EXTE aircraft design, was tested in NASA Langley's 14- by 22-Foot Subsonic Wind Tunnel to study its acoustic characteristics for var- ious propulsion system installation and airframe con gurations. A signi cant upgrade to existing data processing systems was implemented, with a focus on portability and a re- duction in turnaround time. These requirements were met by updating codes originally written for a cluster environment and transferring them to a local workstation while en- abling GPU computing. Post-test, additional processing of the time series was required to remove transient hydrodynamic gusts from some of the microphone time series. A novel automated procedure was developed to analyze and reject contaminated blocks of data, under the assumption that the desired acoustic signal of interest was a band-limited sta- tionary random process, and of lower variance than the hydrodynamic contamination. The procedure is shown to successfully identify and remove contaminated blocks of data and retain the desired acoustic signal. Additional corrections to the data, mainly background subtraction, shear layer refraction calculations, atmospheric attenuation and microphone directivity corrections, were all necessary for initial analysis and noise assessments. These were implemented for the post-processing of spectral data, and are shown to behave as expected.

  13. Applying and validating the RANS-3D flow-solver for evaluating a subsonic serpentine diffuser geometry

    NASA Technical Reports Server (NTRS)

    Fletcher, Michael J.; Won, Mark J.; Cosentino, Gary B.; Te, Alexander

    1993-01-01

    Subsonic inlet ducts for advanced, high-performance aircraft are evolving towards complex three-dimensional shapes for reasons of overall integration and weight. These factors lead to diffuser geometries that may sacrifice inlet performance, unless careful attention to design details and boundary layer management techniques are employed. The ability of viscous computational fluid dynamic (CFD) analysis of such geometries to aid the aircraft configurator in this complex design problem is herein examined. The RANS-3D Reynolds-Averaged Navier-Stokes solver is applied to model the complex flowfield occurring in a representative diffuser geometry and the solutions are compared to experimental results from a static test of the inlet duct. The computational results are shown to compare very favorably with experimental results over a range of mass flow rates, including those involving large amounts of separation in the diffuser. In addition, a novel grid topology is presented, and two turbulence models are evaluated in this study as part of the RANS-3D code.

  14. Subsonic Wake Characterization of the Orion Capsule Using PIV in the Ames UPWT 11-foot Wind Tunnel (Invited)

    NASA Technical Reports Server (NTRS)

    Heineck, James T.; Ross, James C.; Yamauchi, Gloria K.

    2015-01-01

    The subsonic regime of Crew Capsule reentry has a very turbulent waker through which the Drogue Chutes must deploy. This presentation describes the particle image velocimetry measurement campaign used to help retire the risk.

  15. 22 CFR 1006.920 - Civil judgment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 2 2011-04-01 2009-04-01 true Civil judgment. 1006.920 Section 1006.920...) Definitions § 1006.920 Civil judgment. Civil judgment means the disposition of a civil action by any court of... creates a civil liability for the complained of wrongful acts, or a final determination of liability...

  16. 22 CFR 208.920 - Civil judgment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Civil judgment. 208.920 Section 208.920 Foreign...) Definitions § 208.920 Civil judgment. Civil judgment means the disposition of a civil action by any court of... creates a civil liability for the complained of wrongful acts, or a final determination of liability...

  17. 21 CFR 1404.920 - Civil judgment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 9 2011-04-01 2011-04-01 false Civil judgment. 1404.920 Section 1404.920 Food and...) Definitions § 1404.920 Civil judgment. Civil judgment means the disposition of a civil action by any court of... creates a civil liability for the complained of wrongful acts, or a final determination of liability...

  18. 34 CFR 85.920 - Civil judgment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 1 2011-07-01 2011-07-01 false Civil judgment. 85.920 Section 85.920 Education Office...) Definitions § 85.920 Civil judgment. Civil judgment means the disposition of a civil action by any court of... creates a civil liability for the complained of wrongful acts, or a final determination of liability...

  19. 22 CFR 1508.920 - Civil judgment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 2 2011-04-01 2009-04-01 true Civil judgment. 1508.920 Section 1508.920...) Definitions § 1508.920 Civil judgment. Civil judgment means the disposition of a civil action by any court of... creates a civil liability for the complained of wrongful acts, or a final determination of liability...

  20. 22 CFR 1508.920 - Civil judgment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Civil judgment. 1508.920 Section 1508.920...) Definitions § 1508.920 Civil judgment. Civil judgment means the disposition of a civil action by any court of... creates a civil liability for the complained of wrongful acts, or a final determination of liability...

  1. 2 CFR 180.915 - Civil judgment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 2 Grants and Agreements 1 2010-01-01 2010-01-01 false Civil judgment. 180.915 Section 180.915... § 180.915 Civil judgment. Civil judgment means the disposition of a civil action by any court of... creates a civil liability for the complained of wrongful acts, or a final determination of liability...

  2. 22 CFR 208.920 - Civil judgment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Civil judgment. 208.920 Section 208.920 Foreign...) Definitions § 208.920 Civil judgment. Civil judgment means the disposition of a civil action by any court of... creates a civil liability for the complained of wrongful acts, or a final determination of liability...

  3. 22 CFR 1006.920 - Civil judgment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Civil judgment. 1006.920 Section 1006.920...) Definitions § 1006.920 Civil judgment. Civil judgment means the disposition of a civil action by any court of... creates a civil liability for the complained of wrongful acts, or a final determination of liability...

  4. 21 CFR 1404.920 - Civil judgment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Civil judgment. 1404.920 Section 1404.920 Food and...) Definitions § 1404.920 Civil judgment. Civil judgment means the disposition of a civil action by any court of... creates a civil liability for the complained of wrongful acts, or a final determination of liability...

  5. 34 CFR 85.920 - Civil judgment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 1 2010-07-01 2010-07-01 false Civil judgment. 85.920 Section 85.920 Education Office...) Definitions § 85.920 Civil judgment. Civil judgment means the disposition of a civil action by any court of... creates a civil liability for the complained of wrongful acts, or a final determination of liability...

  6. Learning History by Doing: The Laboratory in American Civilization

    ERIC Educational Resources Information Center

    Miller, Zane L.; Shapiro, Henry D.

    1978-01-01

    Reviews development and first two years' experiences of a laboratory course of inquiry into the nature and processes of American civilization through examination of local history as symptomatic history. Faculty, graduate fellows, and advanced undergraduates collaborated on research and analysis of the relationship of culture, environment, and…

  7. INTERACTION OF LASER RADIATION WITH MATTER. LASER PLASMA: Subsonic radiation waves in neon

    NASA Astrophysics Data System (ADS)

    Loseva, T. V.; Nemchinov, I. V.

    1989-02-01

    Numerical methods are used to investigate the propagation of plane subsonic radiation waves in neon from an obstacle in the direction opposite to the incident radiation of Nd and CO2 lasers. An analysis is made of the influence of the power density of the incident radiation (in the range 10-100 MW/cm2) and of the initial density of neon (beginning from the normal valuep ρ0 up to 10ρ0) on the various characteristics of subsonic radiation waves. It is shown that waves traveling in neon can provide an effective source of radiation with a continuous spectrum and an efficiency of ~ 12-27% in the ultraviolet range (with a characteristic photon energy ~ 5-10 eV).

  8. Fluctuation diagrams for hot-wire anemometry in subsonic compressible flows

    NASA Technical Reports Server (NTRS)

    Stainback, P. C.; Nagabushana, K. A.

    1991-01-01

    The concept of using 'fluctuation diagrams' for describing basic fluctuations in compressible flows was reported by Kovasznay in the 1950's. The application of this technique, for the most part, was restricted to supersonic flows. Recently, Zinovev and Lebiga published reports where they considered the fluctuation diagrams in subsonic compressible flows. For the above studies, the velocity and density sensitivities of the heated wires were equal. However, there are considerable data, much taken in the 1950's, which indicate that under some conditions the velocity and density sensitivities are not equal in subsonic compressible flows. Therefore, possible fluctuation diagrams are described for the cases where the velocity and density sensitivities are equal and the more general cases where they are unequal.

  9. Generalization of the subsonic kernel function in the s-plane, with applications to flutter analysis

    NASA Technical Reports Server (NTRS)

    Cunningham, H. J.; Desmarais, R. N.

    1984-01-01

    A generalized subsonic unsteady aerodynamic kernel function, valid for both growing and decaying oscillatory motions, is developed and applied in a modified flutter analysis computer program to solve the boundaries of constant damping ratio as well as the flutter boundary. Rates of change of damping ratios with respect to dynamic pressure near flutter are substantially lower from the generalized-kernel-function calculations than from the conventional velocity-damping (V-g) calculation. A rational function approximation for aerodynamic forces used in control theory for s-plane analysis gave rather good agreement with kernel-function results, except for strongly damped motion at combinations of high (subsonic) Mach number and reduced frequency.

  10. Design Sensitivity for a Subsonic Aircraft Predicted by Neural Network and Regression Models

    NASA Technical Reports Server (NTRS)

    Hopkins, Dale A.; Patnaik, Surya N.

    2005-01-01

    A preliminary methodology was obtained for the design optimization of a subsonic aircraft by coupling NASA Langley Research Center s Flight Optimization System (FLOPS) with NASA Glenn Research Center s design optimization testbed (COMETBOARDS with regression and neural network analysis approximators). The aircraft modeled can carry 200 passengers at a cruise speed of Mach 0.85 over a range of 2500 n mi and can operate on standard 6000-ft takeoff and landing runways. The design simulation was extended to evaluate the optimal airframe and engine parameters for the subsonic aircraft to operate on nonstandard runways. Regression and neural network approximators were used to examine aircraft operation on runways ranging in length from 4500 to 7500 ft.

  11. Validation of a reduced-order jet model for subsonic and underexpanded hydrogen jets

    SciTech Connect

    Li, Xuefang; Hecht, Ethan S.; Christopher, David M.

    2016-01-01

    Much effort has been made to model hydrogen releases from leaks during potential failures of hydrogen storage systems. A reduced-order jet model can be used to quickly characterize these flows, with low computational cost. Notional nozzle models are often used to avoid modeling the complex shock structures produced by the underexpanded jets by determining an “effective” source to produce the observed downstream trends. In our work, the mean hydrogen concentration fields were measured in a series of subsonic and underexpanded jets using a planar laser Rayleigh scattering system. Furthermore, we compared the experimental data to a reduced order jet model for subsonic flows and a notional nozzle model coupled to the jet model for underexpanded jets. The values of some key model parameters were determined by comparisons with the experimental data. Finally, the coupled model was also validated against hydrogen concentrations measurements for 100 and 200 bar hydrogen jets with the predictions agreeing well with data in the literature.

  12. Civil Engineering Technology Needs Assessment.

    ERIC Educational Resources Information Center

    Oakland Community Coll., Farmington, MI. Office of Institutional Planning and Analysis.

    In 1991, a study was conducted by Oakland Community College (OCC) to evaluate the need for a proposed Civil Engineering Technology program. An initial examination of the literature focused on industry needs and the job market for civil engineering technicians. In order to gather information on local area employers' hiring practices and needs, a…

  13. Environmental Ethics and Civil Engineering.

    ERIC Educational Resources Information Center

    Vesilind, P. Aarne

    1987-01-01

    Traces the development of the civil engineering code of ethics. Points out that the code does have an enforceable provision that addresses the engineer's responsibility toward the environment. Suggests revisions to the code to accommodate the environmental impacts of civil engineering. (TW)

  14. Defense Support to Civil Authorities

    DTIC Science & Technology

    2008-05-22

    Response Authority and Other Military Assistance to Civil Authority ( MACA ) [on-line pamphlet], The Army Lawyer (Charlottesville, VA: Judge Advocate...City Bombing: Immediate Response Authority and Other Military Assistance to Civil Authority ( MACA ). The Army Lawyer. [Charlottesville, VA]: Judge

  15. Introducing Islamic Civilization: Course Syllabus.

    ERIC Educational Resources Information Center

    Smith, Reuben W., Ed.

    The syllabus reflects a course in Islamic civilization taught at the University of Chicago and includes the recommendations of participants at a conference on the problems of presenting such a course. The "civilization approach" offers a panoramic view of various related fields, affords a perspective on the problems of analyzing changes over time,…

  16. The incorporation of plotting capability into the Unified Subsonic Supersonic Aerodynamic Analysis program, version B

    NASA Technical Reports Server (NTRS)

    Winter, O. A.

    1980-01-01

    The B01 version of the United Subsonic Supersonic Aerodynamic Analysis program is the result of numerous modifications and additions made to the B00 version. These modifications and additions affect the program input, its computational options, the code readability, and the overlay structure. The following are described: (1) the revised input; (2) the plotting overlay programs which were also modified, and their associated subroutines, (3) the auxillary files used by the program, the revised output data; and (4) the program overlay structure.

  17. The drag force on a subsonic projectile in a fluid complex plasma

    SciTech Connect

    Ivlev, A. V.; Zhukhovitskii, D. I.

    2012-09-15

    The incompressible Navier-Stokes equation is employed to describe a subsonic particle flow induced in complex plasmas by a moving projectile. Drag forces acting on the projectile in different flow regimes are calculated. It is shown that, along with the regular neutral gas drag, there is an additional force exerted on the projectile due to dissipation in the surrounding particle fluid. This additional force provides significant contribution to the total drag.

  18. Fundamental Studies of SUBSONIC and Transonic Flow Separation. Part 3. Third Phase Summary Report

    DTIC Science & Technology

    1979-10-01

    Direction in the Immediate Downstream of a Normal Shock Measured by Cone Probe . . . . . . . . . . . . . . . . 34 Typical Oil Flow Over Ramp Compression...Shallow- Cavity Model . . . . . . . . . . . . . 82 A Typical Oil Flow Pattern Upstream and on the Forward-Facing Step .... 83 Variation of Base...Unit Reynolds number range Reynolds number range based on length from leading edge Maximum temperature drop (°C) for i0 sec. Subsonic flow

  19. Automatic computation of Euler-marching and subsonic grids for wing-fuselage configurations

    NASA Technical Reports Server (NTRS)

    Barger, Raymond L.; Adams, Mary S.; Krishnan, Ramki R.

    1994-01-01

    Algebraic procedures are described for the automatic generation of structured, single-block flow computation grids for relatively simple configurations (wing, fuselage, and fin). For supersonic flows, a quasi two-dimensional grid for Euler-marching codes is developed, and some sample results in graphical form are included. A type of grid for subsonic flow calculation is also described. The techniques are algebraic and are based on a generalization of the method of transfinite interpolation.

  20. Langley 14- by 22-foot subsonic tunnel test engineer's data acquisition and reduction manual

    NASA Technical Reports Server (NTRS)

    Quinto, P. Frank; Orie, Nettie M.

    1994-01-01

    The Langley 14- by 22-Foot Subsonic Tunnel is used to test a large variety of aircraft and nonaircraft models. To support these investigations, a data acquisition system has been developed that has both static and dynamic capabilities. The static data acquisition and reduction system is described; the hardware and software of this system are explained. The theory and equations used to reduce the data obtained in the wind tunnel are presented; the computer code is not included.

  1. Influence matrix program for aerodynamic lifting surface theory. [in subsonic flows

    NASA Technical Reports Server (NTRS)

    Medan, R. T.; Ray, K. S.

    1973-01-01

    A users manual is described for a USA FORTRAN 4 computer program which computes an aerodynamic influence matrix and is one of several computer programs used to analyze lifting, thin wings in steady, subsonic flow according to a kernel function method lifting surface theory. The most significant features of the program are that it can treat unsymmetrical wings, control points can be placed on the leading and/or trailing edges, and a stable, efficient algorithm is used to compute the influence matrix.

  2. Unsteady effects of a control surface in two dimensional subsonic and transonic flow

    NASA Technical Reports Server (NTRS)

    Grenon, R.; Desopper, A.; Sides, J.

    1980-01-01

    The experimental results of steady and unsteady pressure measurements, carried out in subsonic and transonic flow on a 16 percent relative thickness supercritical aerofoil, equipped with a trailing edge flap involving 25 percent of the chord, in a sinusoidal motion are given. These experimental results are compared with those obtained by various methods of steady and unsteady inviscid flow calculations. Some calculation results in which viscous effects have been taken into account, for both steady and unsteady flows, are also presented.

  3. High speed civil transport

    NASA Technical Reports Server (NTRS)

    Bogardus, Scott; Loper, Brent; Nauman, Chris; Page, Jeff; Parris, Rusty; Steinbach, Greg

    1990-01-01

    The design process of the High Speed Civil Transport (HSCT) combines existing technology with the expectation of future technology to create a Mach 3.0 transport. The HSCT was designed to have a range in excess of 6000 nautical miles and carry up to 300 passengers. This range will allow the HSCT to service the economically expanding Pacific Basin region. Effort was made in the design to enable the aircraft to use conventional airports with standard 12,000 foot runways. With a takeoff thrust of 250,000 pounds, the four supersonic through-flow engines will accelerate the HSCT to a cruise speed of Mach 3.0. The 679,000 pound (at takeoff) HSCT is designed to cruise at an altitude of 70,000 feet, flying above most atmospheric disturbances.

  4. The rivers of civilization

    NASA Astrophysics Data System (ADS)

    Macklin, Mark G.; Lewin, John

    2015-04-01

    The hydromorphic regimes that underpinned Old World river-based civilizations are reviewed in light of recent research. Notable Holocene climatic changes varied from region to region, whilst the dynamics of floodplain environments were equally diverse, with river channel changes significantly affecting human settlement. There were longer-term trends in Holocene hydroclimate and multi-centennial length 'flood-rich' and 'flood-poor' episodes. These impacted on five identified flooding and settlement scenarios: (i) alluvial fans and aprons; (ii) laterally mobile rivers; (iii) rivers with well-developed levees and flood basins; (iv) river systems characterised by avulsions and floodouts; and (v) large river-fed wetlands. This gave a range of changes that were either more or less regular or incremental from year-to-year (and thus potentially manageable) or catastrophic. The latter might be sudden during a flood event or a few seasons (acute), or over longer periods extending over many decades or even centuries (chronic). The geomorphic and environmental impacts of these events on riparian societies were very often irreversible. Contrasts are made between allogenic and autogenic mechanism for imposing environmental stress on riverine communities and a distinction is made between channel avulsion and contraction responses. Floods, droughts and river channel changes can precondition as well as trigger environmental crises and societal collapse. The Nile system currently offers the best set of independently dated Holocene fluvial and archaeological records, and the contrasted effects of changing hydromorphological regimes on floodwater farming are examined. The persistence of civilizations depended essentially on the societies that maintained them, but they were also understandably resilient in some environments (Pharaonic Egypt in the Egyptian Nile), appear to have had more limited windows of opportunity in others (the Kerma Kingdom in the Nubian Nile), or required

  5. Advanced High-Temperature Engine Materials Technology Progresses

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The objective of the Advanced High Temperature Engine Materials Technology Program (HITEMP) is to generate technology for advanced materials and structural analysis that will increase fuel economy, improve reliability, extend life, and reduce operating costs for 21st century civil propulsion systems. The primary focus is on fan and compressor materials (polymer-matrix composites--PMC's), compressor and turbine materials (superalloys, and metal-matrix and intermetallic-matrix composites--MMC's and IMC's) and turbine materials (ceramic-matrix composites--CMC's). These advanced materials are being developed by in-house researchers and on grants and contracts. NASA considers this program to be a focused materials and structures research effort that builds on our base research programs and supports component-development projects. HITEMP is coordinated with the Advanced Subsonic Technology (AST) Program and the Department of Defense/NASA Integrated High-Performance Turbine Engine Technology (IHPTET) Program. Advanced materials and structures technologies from HITEMP may be used in these future applications. Recent technical accomplishments have not only improved the state-of-the-art but have wideranging applications to industry. A high-temperature thin-film strain gage was developed to measure both dynamic and static strain up to 1100 C (2000 F). The gage's unique feature is that it is minimally intrusive. This technology, which received a 1995 R&D 100 Award, has been transferred to AlliedSignal Engines, General Electric Company, and Ford Motor Company. Analytical models developed at the NASA Lewis Research Center were used to study Textron Specialty Materials' manufacturing process for titanium-matrix composite rings. Implementation of our recommendations on tooling and processing conditions resulted in the production of defect free rings. In the Lincoln Composites/AlliedSignal/Lewis cooperative program, a composite compressor case is being manufactured with a Lewis

  6. Subsonic flight test evaluation of a performance seeking control algorithm on an F-15 airplane

    NASA Technical Reports Server (NTRS)

    Gilyard, Glenn B.; Orme, John S.

    1992-01-01

    The subsonic flight test evaluation phase of the NASA F-15 (powered by F 100 engines) performance seeking control program was completed for single-engine operation at part- and military-power settings. The subsonic performance seeking control algorithm optimizes the quasi-steady-state performance of the propulsion system for three modes of operation. The minimum fuel flow mode minimizes fuel consumption. The minimum thrust mode maximizes thrust at military power. Decreases in thrust-specific fuel consumption of 1 to 2 percent were measured in the minimum fuel flow mode; these fuel savings are significant, especially for supersonic cruise aircraft. Decreases of up to approximately 100 degree R in fan turbine inlet temperature were measured in the minimum temperature mode. Temperature reductions of this magnitude would more than double turbine life if inlet temperature was the only life factor. Measured thrust increases of up to approximately 15 percent in the maximum thrust mode cause substantial increases in aircraft acceleration. The system dynamics of the closed-loop algorithm operation were good. The subsonic flight phase has validated the performance seeking control technology, which can significantly benefit the next generation of fighter and transport aircraft.

  7. Nonlinear evolution of subsonic and supersonic disturbances on a compressible free shear layer

    NASA Technical Reports Server (NTRS)

    Leib, S. J.

    1991-01-01

    The effects of a nonlinear-nonequilibrium-viscous critical layer on the spatial evolution of subsonic and supersonic instability modes on a compressible free shear layer is considered. It is shown that the instability wave amplitude is governed by an integrodifferential equation with cubic-type nonlinearity. Numerical and asymptotic solutions to this equation show that the amplitude either ends in a singularity at a finite downstream distance or reaches an equilibrium value, depending on the Prandtl number, viscosity law, viscous parameter and a real parameter which is determined by the linear inviscid stability theory. A necessary condition for the existence of the equilibrium solution is derived, and whether or not this condition is met is determined numerically for a wide range of physical parameters including both subsonic and supersonic disturbances. it is found that no equilibrium solution exists for the subsonic modes unless the temperature ratio of the low-to-high-speed streams exceeds a critical value, while equilibrium solutions for the most rapidly growing supersonic mode exist over most of the parameter range examined.

  8. A New Density Variance-Mach Number Relation for Subsonic and Supersonic Isothermal Turbulence

    NASA Astrophysics Data System (ADS)

    Konstandin, L.; Girichidis, P.; Federrath, C.; Klessen, R. S.

    2012-12-01

    The probability density function of the gas density in subsonic and supersonic, isothermal, driven turbulence is analyzed using a systematic set of hydrodynamical grid simulations with resolutions of up to 10243 cells. We perform a series of numerical experiments with root-mean-square (rms) Mach number {M} ranging from the nearly incompressible, subsonic ( {M}=0.1) to the highly compressible, supersonic ( {M}=15) regime. We study the influence of two extreme cases for the driving mechanism by applying a purely solenoidal (divergence-free) and a purely compressive (curl-free) forcing field to drive the turbulence. We find that our measurements fit the linear relation between the rms Mach number and the standard deviation (std. dev.) of the density distribution in a wide range of Mach numbers, where the proportionality constant depends on the type of forcing. In addition, we propose a new linear relation between the std. dev. of the density distribution σρ and that of the velocity in compressible modes, i.e., the compressible component of the rms Mach number, {M}_{{comp}}. In this relation the influence of the forcing is significantly reduced, suggesting a linear relation between σρ and {M}_{{comp}}, independent of the forcing, and ranging from the subsonic to the supersonic regime.

  9. The Performance of a Subsonic Diffuser Designed for High Speed Turbojet-Propelled Flight

    NASA Technical Reports Server (NTRS)

    Biesiadny, Thomas J. (Technical Monitor); Wendt, Bruce J.

    2004-01-01

    An initial-phase subsonic diffuser has been designed for the turbojet flowpath of the hypersonic x43B flight demonstrator vehicle. The diffuser fit into a proposed mixed-compression supersonic inlet system and featured a cross-sectional shape transitioning flowpath (high aspect ratio rectangular throat-to-circular engine face) and a centerline offset. This subsonic diffuser has been fabricated and tested at the W1B internal flow facility at NASA Glenn Research Center. At an operating throat Mach number of 0.79, baseline Pitot pressure recovery was found to be just under 0.9, and DH distortion intensity was about 0.4 percent. The diffuser internal flow stagnated, but did not separate on the offset surface of this initial-phase subsonic diffuser. Small improvements in recovery (+0.4 percent) and DH distortion (-32 percent) were obtained from using vane vortex generator flow control applied just downstream of the diffuser throat. The optimum vortex generator array patterns produced inflow boundary layer divergence (local downwash) on the offset surface centerline of the diffuser, and an inflow boundary layer convergence (local upwash) on the centerline of the opposite surface.

  10. Civil propulsion technology for the next twenty-five years

    NASA Technical Reports Server (NTRS)

    Rosen, Robert; Facey, John R.

    1987-01-01

    The next twenty-five years will see major advances in civil propulsion technology that will result in completely new aircraft systems for domestic, international, commuter and high-speed transports. These aircraft will include advanced aerodynamic, structural, and avionic technologies resulting in major new system capabilities and economic improvements. Propulsion technologies will include high-speed turboprops in the near term, very high bypass ratio turbofans, high efficiency small engines and advanced cycles utilizing high temperature materials for high-speed propulsion. Key fundamental enabling technologies include increased temperature capability and advanced design methods. Increased temperature capability will be based on improved composite materials such as metal matrix, intermetallics, ceramics, and carbon/carbon as well as advanced heat transfer techniques. Advanced design methods will make use of advances in internal computational fluid mechanics, reacting flow computation, computational structural mechanics and computational chemistry. The combination of advanced enabling technologies, new propulsion concepts and advanced control approaches will provide major improvements in civil aircraft.

  11. Civil Code, 11 December 1987.

    PubMed

    1988-01-01

    Article 162 of this Mexican Code provides, among other things, that "Every person has the right freely, responsibly, and in an informed fashion to determine the number and spacing of his or her children." When a marriage is involved, this right is to be observed by the spouses "in agreement with each other." The civil codes of the following states contain the same provisions: 1) Baja California (Art. 159 of the Civil Code of 28 April 1972 as revised in Decree No. 167 of 31 January 1974); 2) Morelos (Art. 255 of the Civil Code of 26 September 1949 as revised in Decree No. 135 of 29 December 1981); 3) Queretaro (Art. 162 of the Civil Code of 29 December 1950 as revised in the Act of 9 January 1981); 4) San Luis Potosi (Art. 147 of the Civil Code of 24 March 1946 as revised in 13 June 1978); Sinaloa (Art. 162 of the Civil Code of 18 June 1940 as revised in Decree No. 28 of 14 October 1975); 5) Tamaulipas (Art. 146 of the Civil Code of 21 November 1960 as revised in Decree No. 20 of 30 April 1975); 6) Veracruz-Llave (Art. 98 of the Civil Code of 1 September 1932 as revised in the Act of 30 December 1975); and 7) Zacatecas (Art. 253 of the Civil Code of 9 February 1965 as revised in Decree No. 104 of 13 August 1975). The Civil Codes of Puebla and Tlaxcala provide for this right only in the context of marriage with the spouses in agreement. See Art. 317 of the Civil Code of Puebla of 15 April 1985 and Article 52 of the Civil Code of Tlaxcala of 31 August 1976 as revised in Decree No. 23 of 2 April 1984. The Family Code of Hidalgo requires as a formality of marriage a certification that the spouses are aware of methods of controlling fertility, responsible parenthood, and family planning. In addition, Article 22 the Civil Code of the Federal District provides that the legal capacity of natural persons is acquired at birth and lost at death; however, from the moment of conception the individual comes under the protection of the law, which is valid with respect to the

  12. Aviation safety and automation technology for subsonic transports

    NASA Technical Reports Server (NTRS)

    Albers, James A.

    1991-01-01

    Discussed here are aviation safety human factors and air traffic control (ATC) automation research conducted at the NASA Ames Research Center. Research results are given in the areas of flight deck and ATC automations, displays and warning systems, crew coordination, and crew fatigue and jet lag. Accident investigation and an incident reporting system that is used to guide the human factors research is discussed. A design philosophy for human-centered automation is given, along with an evaluation of automation on advanced technology transports. Intelligent error tolerant systems such as electronic checklists are discussed along with design guidelines for reducing procedure errors. The data on evaluation of Crew Resource Management (CRM) training indicates highly significant positive changes in appropriate flight deck behavior and more effective use of available resources for crew members receiving the training.

  13. Subsonic Reynolds Number Effects on a Diamond Wing Configuration

    NASA Technical Reports Server (NTRS)

    Luckring, J. M.; Ghee, T. A.

    2001-01-01

    An advanced diamond-wing configuration was tested at low speeds in the National Transonic Facility (NTF) in air at chord Reynolds numbers from 4.4 million (typical wind-tunnel conditions) to 24 million (nominal flight value). Extensive variations on high-lift rigging were explored as part of a broad multinational program. The analysis for this study is focused on the cruise and landing settings of the wing high-lift systems. Three flow domains were identified from the data and provide a context for the ensuing data analysis. Reynolds number effects were examined in incremental form based upon attached-flow theory. A similar approach showed very little effect of low-speed compressibility.

  14. Material civilization: things and society.

    PubMed

    Dant, Tim

    2006-06-01

    This paper argues that although classical sociology has largely overlooked the importance of social relations with the material world in shaping the form of society, Braudel's concept of 'material civilization' is a useful way to begin to understand the sociological significance of this relationship. The limitations of Braudel's historical and general concept can be partially overcome with Elias's analysis of the connection between 'technization' and 'civilization' that allows for both a civilizing and a de-civilizing impact of emergent forms of material relation that both lengthen and shorten the chains of interdependence between the members of a society. It is suggested that the concept of the 'morality of things' employed by a number of commentators is useful in summarizing the civilizing effects of material objects and addressing their sociological significance. From the sociology of consumption the idea of materiality as a sign of social relationships can be drawn, and from the sociology of technology the idea of socio-technical systems and actor-networks can contribute to the understanding of material civilization. It is argued that the concept of 'material capital' can usefully summarize the variable social value of objects but to understand the complexity of material civilization as it unfolds in everyday life, an analysis of 'material interaction' is needed. Finally the paper suggests some initial themes and issues apparent in contemporary society that the sociological study of material civilization might address; the increased volume, functional complexity and material specificity of objects and the increased social complexity, autonomy and substitutability that is entailed. A theory of 'material civilization' is the first step in establishing a sociology of objects.

  15. Technical Civilizations in the Galaxy

    NASA Technical Reports Server (NTRS)

    Jones, Harry

    2005-01-01

    Are there other technical civilizations in the galaxy? Past analyses come to different conclusions. Cocconi and Morrison demonstrated in 1959 that interstellar radio communication was possible and Drake conducted the first search for beacons in 1960. The Drake equation estimates the number of galactic civilizations that are transmitting beacons as the product of the rate of star formation in the galaxy, the fraction of stars with planets, their average number of earthlike planets, the fraction with intelligent life and interstellar communication, and the average lifetime of a technical civilization. The Drake model of the galaxy contains many technical civilizations with communication but no interstellar travel. Michael Hart in 1975 strongly challenged this model. Starting with the fact that no extraterrestrials have been observed on Earth, and assuming that interstellar colonization is possible, he concluded that it was very likely that we are the first civilization in our galaxy and that searching or beacons is probably a waste of time and money. The Fermi paradox similarly reasons that if extraterrestrials exist: they should be here, and asks, Where are they? The Hart/Fermi model of the galaxy contains only our civilization and suggests we may colonize the galaxy. A third galactic model is that we are alone but will never develop interstellar travel. The fourth alternate model has many technical civilizations, with interstellar travel and colonization. The possibilities are clear and momentous. Either we are the only technical civilization in the galaxy or there are others. Technical civilizations will colonize the galaxy or not. We have four cosmic conjectures - one or many, colonization or not - but however unlikely they seem based on our limited evidence, one of these four models must be collect.

  16. Low subsonic aerodynamic characteristics of five irregular planform wings with systematically varying wing fillet geometry tested in the NASA/Ames 12 foot pressure tunnel (LA65)

    NASA Technical Reports Server (NTRS)

    Ball, J. W.; Watson, D. B.

    1976-01-01

    An experimental and analytical aerodynamic program to develop predesign guides for irregular planform wings (also referred to as cranked leading edge or double delta wings is reported; the benefits are linearization of subsonic lift curve slope to high angles of attack and avoidance of subsonic pitch instabilities at high lift by proper tailoring of the planform-fillet-wing combination while providing the desired hypersonic trim angle and stability. Because subsonic and hypersonic conditions were the two prime areas of concern in the initial application of this program to optimize shuttle orbiter landing and entry characteristics, the study was designated the Subsonic/Hypersonic Irregular Planforms Study (SHIPS).

  17. Civil Defense, U. S. A.: A Programmed Orientation to Civil Defense. Unit 5. Governmental Responsibilities for Civil Defense.

    ERIC Educational Resources Information Center

    Defense Civil Preparedness Agency (DOD), Battle Creek, MI.

    A description of the laws and orders that provide necessary legal authorization for civil defense activities is provided. In addition, an outline of the responsibilities of all governments and the role of the private sector in civil defense is presented. Topics discussed include: (1) Legal authority for civil defense, (2) Civil defense…

  18. Credit and civilization.

    PubMed

    Newton, Tim

    2003-09-01

    This paper analyses financial credit in order to re-examine the work of Norbert Elias, particularly his association of interdependency complexity with social discipline, and his approach to contradiction. Following a discussion of these issues, the paper examines Elias's writing on money and explores the emergence of financial credit networks in early modern England. Attention is paid to credit networks and social discipline, to credit and the state, and to the contradictory images associated with the transition to modern cash economies. From one perspective, early modern credit networks might be read as a confirmation of Elias, particularly his argument that interdependency complexity, changing power balances and self-restraint are interwoven. Yet the development of modern cash money raises questions, not just in relation to Elias's treatment of money, but also with regard to his assumptions about social discipline and his approach to ambivalence and contradiction. Drawing on the foregoing discussion, the paper argues that the relation between interdependency complexity and social discipline is contingent and variable, and that interdependency complexity may simultaneously encourage contradictory processes, such as those of civilizing and barbarity.

  19. A Civilization of Explorers

    ERIC Educational Resources Information Center

    Duchesne, Ricardo

    2012-01-01

    The claim that there were "surprising similarities" between the West and the more advanced regions of Asia as late as 1800-1830, and that the Industrial Revolution was the one transformation that set Europe apart from Asia is central to the arguments of multicultural historians such as Kenneth Pomeranz, Bin Wong, Jack Goldstone, John…

  20. Job Prospects for Civil Engineers.

    ERIC Educational Resources Information Center

    Basta, Nicholas

    1988-01-01

    Discusses civil engineering employment opportunities; indicates that the field is shrinking. Presents national placement and enrollment statistics. Identifies building and construction materials, and public works as areas of current and expanding opportunities. (CW)

  1. 77 FR 70710 - Civil Penalties

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-27

    ... Reform Act of 1995, Public Law 104-4, requires agencies to prepare a written assessment of the cost... Mandates assessment will be prepared. Executive Order 12778 (Civil Justice Reform) This rule does not...

  2. 75 FR 79978 - Civil Penalties

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-21

    ... Law 104-4, requires agencies to prepare a written assessment of the cost, benefits and other effects... assessment will be prepared. ] Executive Order 12778 (Civil Justice Reform) This final rule does not have...

  3. Uncertainty in estimates of the number of extraterrestrial civilizations

    NASA Technical Reports Server (NTRS)

    Sturrock, P. A.

    1980-01-01

    An estimation of the number N of communicative civilizations is made by means of Drake's formula which involves the combination of several quantities, each of which is to some extent uncertain. It is shown that the uncertainty in any quantity may be represented by a probability distribution function, even if that quantity is itself a probability. The uncertainty of current estimates of N is derived principally from uncertainty in estimates of the lifetime of advanced civilizations. It is argued that this is due primarily to uncertainty concerning the existence of a Galactic Federation which is in turn contingent upon uncertainty about whether the limitations of present-day physics are absolute or (in the event that there exists a yet undiscovered hyperphysics) transient. It is further argued that it is advantageous to consider explicitly these underlying assumptions in order to compare the probable numbers of civilizations operating radio beacons, permitting radio leakage, dispatching probes for radio surveillance for dispatching vehicles for manned surveillance.

  4. Partnering Guide for Civil Missions.

    DTIC Science & Technology

    1998-04-01

    charter, and even grade each other on a scorecard . All of these collaborative processes can be helpful at different points in the Civil Works program...sign a charter, and even grade each other on a scorecard . All of these collaborative processes can be helpful at different points in the Civil...participants’ credibility is on the line. If specific targets are set in the charter, they should be balanced between realism on the one hand and

  5. 5 CFR 919.920 - Civil judgment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Civil judgment. 919.920 Section 919.920 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 919.920 Civil judgment. Civil...

  6. 21 CFR 1404.920 - Civil judgment.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 9 2012-04-01 2012-04-01 false Civil judgment. 1404.920 Section 1404.920 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 1404.920 Civil judgment. Civil judgment means the disposition of a civil action by any court...

  7. 29 CFR 1471.920 - Civil judgment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... SUSPENSION (NONPROCUREMENT) Definitions § 1471.920 Civil judgment. Civil judgment means the disposition of a civil action by any court of competent jurisdiction, whether by verdict, decision, settlement... 29 Labor 4 2012-07-01 2012-07-01 false Civil judgment. 1471.920 Section 1471.920 Labor...

  8. 30 CFR 912.845 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Civil penalties. 912.845 Section 912.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE IDAHO § 912.845 Civil penalties. Part 845 of this chapter, Civil Penalties, shall apply when civil penalties are assessed for...

  9. 30 CFR 922.845 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Civil penalties. 922.845 Section 922.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE MICHIGAN § 922.845 Civil penalties. Part 845 of this chapter, Civil Penalties, shall apply when civil penalties are assessed for...

  10. 30 CFR 921.845 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Civil penalties. 921.845 Section 921.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE MASSACHUSETTS § 921.845 Civil penalties. Part 845 of this chapter, Civil Penalties, shall apply when civil penalties are assessed...

  11. 30 CFR 947.845 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Civil penalties. 947.845 Section 947.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE WASHINGTON § 947.845 Civil penalties. Part 845 of this chapter, Civil Penalties, shall apply when civil penalties are assessed...

  12. 2 CFR 180.915 - Civil judgment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 2 Grants and Agreements 1 2011-01-01 2011-01-01 false Civil judgment. 180.915 Section 180.915... GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 180.915 Civil judgment. Civil judgment means the disposition of a civil action by any court of competent jurisdiction, whether by...

  13. 29 CFR 1471.920 - Civil judgment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 4 2011-07-01 2011-07-01 false Civil judgment. 1471.920 Section 1471.920 Labor Regulations... SUSPENSION (NONPROCUREMENT) Definitions § 1471.920 Civil judgment. Civil judgment means the disposition of a civil action by any court of competent jurisdiction, whether by verdict, decision,...

  14. 29 CFR 98.920 - Civil judgment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 1 2011-07-01 2011-07-01 false Civil judgment. 98.920 Section 98.920 Labor Office of the Secretary of Labor GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 98.920 Civil judgment. Civil judgment means the disposition of a civil action by any court of competent...

  15. 30 CFR 910.845 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Civil penalties. 910.845 Section 910.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE GEORGIA § 910.845 Civil penalties. Part 845 of this chapter, Civil Penalties, shall apply when civil penalties are assessed for...

  16. 48 CFR 3.807 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Civil penalties. 3.807... Federal Transactions 3.807 Civil penalties. Agencies shall impose and collect civil penalties pursuant to the provisions of the Program Fraud and Civil Remedies Act, 31 U.S.C. 3803 (except subsection...

  17. 30 CFR 942.845 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Civil penalties. 942.845 Section 942.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE TENNESSEE § 942.845 Civil penalties. Part 845 of this chapter, Civil Penalties, shall apply to the assessment of civil penalties...

  18. 30 CFR 939.845 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Civil penalties. 939.845 Section 939.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE RHODE ISLAND § 939.845 Civil penalties. Part 845 of this chapter, Civil Penalties, shall apply when civil penalties are assessed...

  19. 14 CFR 406.9 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Civil penalties. 406.9 Section 406.9... § 406.9 Civil penalties. (a) Civil penalty liability. Under 49 U.S.C. 70115(c), a person found by the... civil penalty of not more than $110,000 for each violation, as adjusted for inflation. A...

  20. 30 CFR 941.845 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Civil penalties. 941.845 Section 941.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE SOUTH DAKOTA § 941.845 Civil penalties. Part 845 of this chapter, Civil Penalties, shall apply when civil penalties are assessed...

  1. 30 CFR 905.845 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Civil penalties. 905.845 Section 905.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE CALIFORNIA § 905.845 Civil penalties. Part 845 of this chapter, Civil Penalties, shall apply to the assessment of civil penalties...

  2. 31 CFR 19.920 - Civil judgment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance: Treasury 1 2011-07-01 2011-07-01 false Civil judgment. 19.920 Section 19.920... SUSPENSION (NONPROCUREMENT) Definitions § 19.920 Civil judgment. Civil judgment means the disposition of a civil action by any court of competent jurisdiction, whether by verdict, decision,...

  3. 5 CFR 919.920 - Civil judgment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Civil judgment. 919.920 Section 919.920 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 919.920 Civil judgment. Civil...

  4. 30 CFR 937.845 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Civil penalties. 937.845 Section 937.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE OREGON § 937.845 Civil penalties. Part 845 of this chapter, Civil Penalties, shall apply when civil penalties are assessed for...

  5. 30 CFR 903.845 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Civil penalties. 903.845 Section 903.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE ARIZONA § 903.845 Civil penalties. Part 845 of this chapter, Civil Penalties, applies to the assessment of civil penalties for...

  6. 30 CFR 933.845 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Civil penalties. 933.845 Section 933.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE NORTH CAROLINA § 933.845 Civil penalties. Part 845 of this chaper, Civil Penalties, shall apply when civil penalties are assessed...

  7. Communication Needs of Thai Civil Engineering Students

    ERIC Educational Resources Information Center

    Kaewpet, Chamnong

    2009-01-01

    This article reports on an examination of the communication needs of a group of Thai civil engineering students. Twenty-five stakeholders helped identify the communication needs of the students by participating in individual interviews. These included employers, civil engineers, civil engineering lecturers, ex-civil engineering students of the…

  8. 28 CFR 31.202 - Civil rights.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 28 Judicial Administration 1 2011-07-01 2011-07-01 false Civil rights. 31.202 Section 31.202....202 Civil rights. (a) To carry out the State's Federal civil rights responsibilities the plan must: (1) Designate a civil rights contact person who has lead responsibility in insuring that all applicable...

  9. 14 CFR 1274.924 - Civil rights.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 5 2013-01-01 2013-01-01 false Civil rights. 1274.924 Section 1274.924... FIRMS Other Provisions and Special Conditions § 1274.924 Civil rights. Civil Rights July 2002 Work on NASA cooperative agreements is subject to the provisions of Title VI of the Civil Rights Act of...

  10. 28 CFR 31.202 - Civil rights.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 28 Judicial Administration 1 2013-07-01 2013-07-01 false Civil rights. 31.202 Section 31.202....202 Civil rights. (a) To carry out the State's Federal civil rights responsibilities the plan must: (1) Designate a civil rights contact person who has lead responsibility in insuring that all applicable...

  11. 14 CFR 1274.924 - Civil rights.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 5 2012-01-01 2012-01-01 false Civil rights. 1274.924 Section 1274.924... FIRMS Other Provisions and Special Conditions § 1274.924 Civil rights. Civil Rights July 2002 Work on NASA cooperative agreements is subject to the provisions of Title VI of the Civil Rights Act of...

  12. 7 CFR 2500.056 - Civil rights.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Civil rights. 2500.056 Section 2500.056 Agriculture... Closeout § 2500.056 Civil rights. Awardees must comply with the civil rights requirements of 7 CFR part 15, subpart A—USDA implementation of Title VI of the Civil Rights Act of 1964, as amended. In accordance,...

  13. 14 CFR 1274.924 - Civil rights.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 5 2011-01-01 2010-01-01 true Civil rights. 1274.924 Section 1274.924... FIRMS Other Provisions and Special Conditions § 1274.924 Civil rights. Civil Rights July 2002 Work on NASA cooperative agreements is subject to the provisions of Title VI of the Civil Rights Act of...

  14. 28 CFR 31.202 - Civil rights.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 28 Judicial Administration 1 2012-07-01 2012-07-01 false Civil rights. 31.202 Section 31.202....202 Civil rights. (a) To carry out the State's Federal civil rights responsibilities the plan must: (1) Designate a civil rights contact person who has lead responsibility in insuring that all applicable...

  15. 14 CFR 1274.924 - Civil rights.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Civil rights. 1274.924 Section 1274.924... FIRMS Other Provisions and Special Conditions § 1274.924 Civil rights. Civil Rights July 2002 Work on NASA cooperative agreements is subject to the provisions of Title VI of the Civil Rights Act of...

  16. 7 CFR 2500.056 - Civil rights.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Civil rights. 2500.056 Section 2500.056 Agriculture... Closeout § 2500.056 Civil rights. Awardees must comply with the civil rights requirements of 7 CFR part 15, subpart A—USDA implementation of Title VI of the Civil Rights Act of 1964, as amended. In accordance,...

  17. 7 CFR 2500.056 - Civil rights.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 15 2012-01-01 2012-01-01 false Civil rights. 2500.056 Section 2500.056 Agriculture... Closeout § 2500.056 Civil rights. Awardees must comply with the civil rights requirements of 7 CFR part 15, subpart A—USDA implementation of Title VI of the Civil Rights Act of 1964, as amended. In accordance,...

  18. 28 CFR 31.202 - Civil rights.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 28 Judicial Administration 1 2014-07-01 2014-07-01 false Civil rights. 31.202 Section 31.202....202 Civil rights. (a) To carry out the State's Federal civil rights responsibilities the plan must: (1) Designate a civil rights contact person who has lead responsibility in insuring that all applicable...

  19. 30 CFR 933.845 - Civil penalties.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Civil penalties. 933.845 Section 933.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE NORTH CAROLINA § 933.845 Civil penalties. Part 845 of this chaper, Civil Penalties, shall apply when civil penalties are assessed...

  20. 30 CFR 922.845 - Civil penalties.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Civil penalties. 922.845 Section 922.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE MICHIGAN § 922.845 Civil penalties. Part 845 of this chapter, Civil Penalties, shall apply when civil penalties are assessed for...

  1. 30 CFR 937.845 - Civil penalties.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Civil penalties. 937.845 Section 937.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE OREGON § 937.845 Civil penalties. Part 845 of this chapter, Civil Penalties, shall apply when civil penalties are assessed for...

  2. 29 CFR 98.920 - Civil judgment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 1 2010-07-01 2010-07-01 true Civil judgment. 98.920 Section 98.920 Labor Office of the Secretary of Labor GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 98.920 Civil judgment. Civil judgment means the disposition of a civil action by any court of competent...

  3. 30 CFR 921.845 - Civil penalties.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Civil penalties. 921.845 Section 921.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE MASSACHUSETTS § 921.845 Civil penalties. Part 845 of this chapter, Civil Penalties, shall apply when civil penalties are assessed...

  4. 7 CFR 3017.920 - Civil judgment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Civil judgment. 3017.920 Section 3017.920 Agriculture... AGRICULTURE GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 3017.920 Civil judgment. Civil judgment means the disposition of a civil action by any court of competent jurisdiction,...

  5. 30 CFR 942.845 - Civil penalties.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Civil penalties. 942.845 Section 942.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE TENNESSEE § 942.845 Civil penalties. Part 845 of this chapter, Civil Penalties, shall apply to the assessment of civil penalties...

  6. 30 CFR 912.845 - Civil penalties.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Civil penalties. 912.845 Section 912.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE IDAHO § 912.845 Civil penalties. Part 845 of this chapter, Civil Penalties, shall apply when civil penalties are assessed for...

  7. 30 CFR 941.845 - Civil penalties.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Civil penalties. 941.845 Section 941.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE SOUTH DAKOTA § 941.845 Civil penalties. Part 845 of this chapter, Civil Penalties, shall apply when civil penalties are assessed...

  8. 14 CFR 406.9 - Civil penalties.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Civil penalties. 406.9 Section 406.9... § 406.9 Civil penalties. (a) Civil penalty liability. Under 49 U.S.C. 70115(c), a person found by the... civil penalty of not more than $100,000 for each violation, as adjusted for inflation. A...

  9. 30 CFR 905.845 - Civil penalties.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Civil penalties. 905.845 Section 905.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE CALIFORNIA § 905.845 Civil penalties. Part 845 of this chapter, Civil Penalties, shall apply to the assessment of civil penalties...

  10. 48 CFR 3.807 - Civil penalties.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Civil penalties. 3.807... Federal Transactions 3.807 Civil penalties. Agencies shall impose and collect civil penalties pursuant to the provisions of the Program Fraud and Civil Remedies Act, 31 U.S.C. 3803 (except subsection...

  11. 29 CFR 1471.920 - Civil judgment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 4 2010-07-01 2010-07-01 false Civil judgment. 1471.920 Section 1471.920 Labor Regulations... SUSPENSION (NONPROCUREMENT) Definitions § 1471.920 Civil judgment. Civil judgment means the disposition of a civil action by any court of competent jurisdiction, whether by verdict, decision,...

  12. 30 CFR 939.845 - Civil penalties.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Civil penalties. 939.845 Section 939.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE RHODE ISLAND § 939.845 Civil penalties. Part 845 of this chapter, Civil Penalties, shall apply when civil penalties are assessed...

  13. 30 CFR 947.845 - Civil penalties.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Civil penalties. 947.845 Section 947.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE WASHINGTON § 947.845 Civil penalties. Part 845 of this chapter, Civil Penalties, shall apply when civil penalties are assessed...

  14. 31 CFR 19.920 - Civil judgment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Civil judgment. 19.920 Section 19.920... SUSPENSION (NONPROCUREMENT) Definitions § 19.920 Civil judgment. Civil judgment means the disposition of a civil action by any court of competent jurisdiction, whether by verdict, decision,...

  15. 30 CFR 903.845 - Civil penalties.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Civil penalties. 903.845 Section 903.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE ARIZONA § 903.845 Civil penalties. Part 845 of this chapter, Civil Penalties, applies to the assessment of civil penalties for...

  16. 30 CFR 910.845 - Civil penalties.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Civil penalties. 910.845 Section 910.845... PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE GEORGIA § 910.845 Civil penalties. Part 845 of this chapter, Civil Penalties, shall apply when civil penalties are assessed for...

  17. 50 CFR 697.11 - Civil procedures.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Civil procedures. 697.11 Section 697.11 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION....11 Civil procedures. The civil procedure regulations at 15 CFR part 904 apply to civil...

  18. Space civil engineering - A new discipline

    NASA Technical Reports Server (NTRS)

    Sadeh, Willy Z.; Criswell, Marvin E.

    1991-01-01

    Space Civil Engineering is an emerging engineering discipline that focuses on extending and expanding the Civil Engineering know-how and practice to the development and maintenance of infrastructure on celestial bodies. Space Civil Engineering is presently being developed as a new discipline within the Department of Civil Engineering at Colorado State University under a recently established NASA Space Grant College Program. Academic programs geared toward creating Space Civil Engineering Options at both undergraduate and graduate levels are being formulated. Basic ideas and concepts of the curriculum in the Space Civil Engineering Option at both undergraduate and graduate levels are presented. The role of Space Civil Engineering in the Space Program is discussed.

  19. The impact of emerging technologies on an advanced supersonic transport

    NASA Technical Reports Server (NTRS)

    Driver, C.; Maglieri, D. J.

    1986-01-01

    The effects of advances in propulsion systems, structure and materials, aerodynamics, and systems on the design and development of supersonic transport aircraft are analyzed. Efficient propulsion systems with variable-cycle engines provide the basis for improved propulsion systems; the propulsion efficienies of supersonic and subsonic engines are compared. Material advances consist of long-life damage-tolerant structures, advanced material development, aeroelastic tailoring, and low-cost fabrication. Improvements in the areas of aerodynamics and systems are examined. The environmental problems caused by engine emissions, airport noise, and sonic boom are studied. The characteristics of the aircraft designed to include these technical advances are described.

  20. Improved Performances in Subsonic Flows of an SPH Scheme with Gradients Estimated Using an Integral Approach

    NASA Astrophysics Data System (ADS)

    Valdarnini, R.

    2016-11-01

    In this paper, we present results from a series of hydrodynamical tests aimed at validating the performance of a smoothed particle hydrodynamics (SPH) formulation in which gradients are derived from an integral approach. We specifically investigate the code behavior with subsonic flows, where it is well known that zeroth-order inconsistencies present in standard SPH make it particularly problematic to correctly model the fluid dynamics. In particular, we consider the Gresho-Chan vortex problem, the growth of Kelvin-Helmholtz instabilities, the statistics of driven subsonic turbulence and the cold Keplerian disk problem. We compare simulation results for the different tests with those obtained, for the same initial conditions, using standard SPH. We also compare the results with the corresponding ones obtained previously with other numerical methods, such as codes based on a moving-mesh scheme or Godunov-type Lagrangian meshless methods. We quantify code performances by introducing error norms and spectral properties of the particle distribution, in a way similar to what was done in other works. We find that the new SPH formulation exhibits strongly reduced gradient errors and outperforms standard SPH in all of the tests considered. In fact, in terms of accuracy, we find good agreement between the simulation results of the new scheme and those produced using other recently proposed numerical schemes. These findings suggest that the proposed method can be successfully applied for many astrophysical problems in which the presence of subsonic flows previously limited the use of SPH, with the new scheme now being competitive in these regimes with other numerical methods.

  1. Effect of impinging plate geometry on the self-excitation of subsonic impinging jets

    NASA Astrophysics Data System (ADS)

    Vinoth, B. R.; Rathakrishnan, E.

    2011-11-01

    In the generation of discrete tones by subsonic impinging jets, there exists a difference of opinion as how the feedback is achieved, i.e., the path of the feedback acoustic waves is whether inside the jet or outside the jet? The only available model (Tam and Ahuja model) for the prediction of an average subsonic jet impingement tone frequency assumes that the upstream part of the feedback loop is closed by an upstream propagating neutral wave of the jet. But, there is no information about the plate geometry in the model. The present study aims at understanding the effect of the plate geometry (size and co-axial hole in the plate) on the self-excitation process of subsonic impinging jets and the path of the acoustic feedback to the nozzle exit. The present results show that there is no effect of plate diameter on the frequency of the self-excitation. A new type of tones is generated for plates with co-axial hole (hole diameter is equal to nozzle exit diameter) for Mach numbers 0.9 and 0.95, in addition to the axisymmetric and helical mode tones observed for plates without co-axial hole. The stability results show that the Strouhal number of the least dispersive upstream propagating neutral waves match with the average Strouhal number of the new tones observed in the present experiments. The present study extends the validity of the model of Tam and Ahuja to a plate with co-axial hole (annular plate) and by doing so, we indirectly confirmed that the major acoustic feedback path to the nozzle exit is inside the jet.

  2. Observations of subsonic and supersonic shear flows in laser driven high-energy-density plasmas

    NASA Astrophysics Data System (ADS)

    Harding, E. C.

    2009-11-01

    Shear layers containing strong velocity gradients appear in many high-energy-density (HED) systems and play important roles in mixing and the transition to turbulence. Yet few laboratory experiments have been carried out to study their detailed evolution in this extreme environment where plasmas are compressible, actively ionizing, often involve strong shock waves and have complex material properties. Many shear flows produce the Kelvin-Helmholtz (KH) instability, which initiates the mixing at a fluid interface. We present results from two dedicated shear flow experiments that produced overall subsonic and supersonic flows using novel target designs. In the subsonic case, the Omega laser was used to drive a blast wave along a rippled interface between plastic and foam, shocking both the materials to produce two fluids separated by a sharp shear layer. The interface subsequently rolled-upped into large KH vortices that were accompanied by bubble-like structures of unknown origin. This was the first time the evolution of a well-resolved KH instability was observed in a HED plasma in the laboratory. We have analyzed the properties and dynamics of the plasma based on the data and fundamental models, without resorting to simulated values. In the second, supersonic experiment the Nike laser was used to drive a supersonic flow of Al plasma along a rippled, low-density foam surface. Here again the flowing plasma drove a shock into the second material, so that two fluids were separated by a shear layer. In contrast to the subsonic case, the flow developed shocks around the ripples in response to the supersonic flow of Al. Collaborators: R.P. Drake, O.A. Hurricane, J.F. Hansen, Y. Aglitskiy, T. Plewa, B.A. Remington, H.F. Robey, J.L. Weaver, A.L. Velikovich, R.S. Gillespie, M.J. Bono, M.J. Grosskopf, C.C. Kuranz, A. Visco.

  3. Pressure measurements on a thick cambered and twisted 58 deg delta wing at high subsonic speeds

    NASA Technical Reports Server (NTRS)

    Chu, Julio; Lamar, John E.

    1987-01-01

    A pressure experiment at high subsonic speeds was conducted by a cambered and twisted thick delta wing at the design condition (Mach number 0.80), as well as at nearby Mach numbers (0.75 and 0.83) and over an angle-of-attack range. Effects of twin vertical tails on the wing pressure measurements were also assessed. Comparisons of detailed theoretical and experimental surface pressures and sectional characteristics for the wing alone are presented. The theoretical codes employed are FLO-57, FLO-28, PAN AIR, and the Vortex Lattice Method-Suction Analogy.

  4. The calculation of pressure on slender airplanes in subsonic and supersonic flow

    NASA Technical Reports Server (NTRS)

    Heaslet, Max A; Lomas, Harvard

    1954-01-01

    Under the assumption that a wing, body, or wing-body combination is slender or flying at near sonic velocity, expressions are given which permit the calculation of pressure in the immediate vicinity of the configuration. The disturbance field, in both subsonic and supersonic flight, is shown to consist of two-dimensional disturbance fields extending laterally and a longitudinal field that depends on the streamwise growth of cross-sectional area. A discussion is also given of couplings, between lifting and thickness effects, that necessarily arise as a result of the quadratic dependence of pressure on the induced velocity components. (author)

  5. Three dimensional flow field measurements of a 4:1 aspect ratio subsonic jet

    NASA Technical Reports Server (NTRS)

    Morrison, G. L.; Swan, D. H.

    1989-01-01

    Flow field measurements for a subsonic rectangular cold air jet with an aspect ratio of 4:1 (12.7 x 50.8 mm) at a Mach number of 0.09 and Re of 100,000 have been carried out using a three-dimensional laser Doppler anemometer system. Mean velocity measurements show that the jet width spreads more rapidly along the minor axis than along the major axis. The outward velocities, however, are not significantly different for the two axes, indicating the presence of enhanced mixing along the minor axis. The jet slowly changes from a rectangular jet to a circular jet as the flow progresses downstream.

  6. Development of a shock noise prediction code for high-speed helicopters - The subsonically moving shock

    NASA Technical Reports Server (NTRS)

    Tadghighi, H.; Holz, R.; Farassat, F.; Lee, Yung-Jang

    1991-01-01

    A previously defined airfoil subsonic shock-noise prediction formula whose result depends on a mapping of the time-dependent shock surface to a time-independent computational domain is presently coded and incorporated in the NASA-Langley rotor-noise prediction code, WOPWOP. The structure and algorithms used in the shock-noise prediction code are presented; special care has been taken to reduce computation time while maintaining accuracy. Numerical examples of shock-noise prediction are presented for hover and forward flight. It is confirmed that shock noise is an important component of the quadrupole source.

  7. Effects of high subsonic flow on sound propagation in a variable-area duct

    NASA Technical Reports Server (NTRS)

    Callegari, A. J.; Myers, M. K.

    1976-01-01

    The propagation of sound in a converging-diverging duct containing a quasi-one-dimensional steady flow with a high subsonic throat Mach number was studied. The behavior of linearized acoustic theory at the throat of the duct was shown to be singular. This singularity implies that linearized acoustic theory is invalid. The explicit singular behavior was determined and used to sketch the development (by the method of matched asymptotic expansions) of a nonlinear theory for sound propagation in a sonic throat region.

  8. Subsonic flutter analysis addition to NASTRAN. [for use with CDC 6000 series digital computers

    NASA Technical Reports Server (NTRS)

    Doggett, R. V., Jr.; Harder, R. L.

    1973-01-01

    A subsonic flutter analysis capability has been developed for NASTRAN, and a developmental version of the program has been installed on the CDC 6000 series digital computers at the Langley Research Center. The flutter analysis is of the modal type, uses doublet lattice unsteady aerodynamic forces, and solves the flutter equations by using the k-method. Surface and one-dimensional spline functions are used to transform from the aerodynamic degrees of freedom to the structural degrees of freedom. Some preliminary applications of the method to a beamlike wing, a platelike wing, and a platelike wing with a folded tip are compared with existing experimental and analytical results.

  9. Pressure Distribution at Subsonic Speeds over the Forepart of Two Blunt Circular Cylinders

    NASA Technical Reports Server (NTRS)

    Lockwood, V. E.

    1975-01-01

    A wind tunnel investigation was made at subsonic speeds to determine the pressure distribution over the forward part of a circular cylinder. The cylinder was equipped with interchangeable faces, one having a flat face and one having a dome shaped face. The investigation was made over angle of attack range from -1 deg to 26 deg and a Mach number range from 0.30 to 0.89. Pressure coefficients are presented in tabular form and plotted data are presented for some selected angles of attack about the surface of the cylinder.

  10. A free-flight experiment of projectiles ranging from high subsonic to high supersonic Mach numbers

    NASA Astrophysics Data System (ADS)

    Oguchi, H.; Funabiki, K.; Sato, S.; Hatakeyama, M.

    1991-09-01

    This paper reports a preliminary experiment with a free-flight range which was designed to be able to be driven by means of a sort of fast-acting valve. The notable characteristics pertinent to this type of range is the pliancy of operation and also the wide coverage of flight speed from the high subsonic to the high supersonic range. For both spherical and vehicle models, flight tests were conducted with shadowgraph observations and flight speed measurements in order to examine the capability of this type of facility.

  11. Exploratory subsonic investigation of vortex-flap concept on arrow wing configuration

    NASA Technical Reports Server (NTRS)

    Rao, D. M.

    1981-01-01

    The drag reduction potential of a vortex flap concept, utilizing the thrust contribution of separation vortices maintained over leading edge flap surfaces, was explored in subsonic wind tunnel tests on a highly swept arrow wing configuration. Several flap geometries were tested in comparison with a previous study on the same model with leading edges drooped for attached flow. The most promising vortex flap arrangements produced drag reductions comparable with leading edge droop over a range of lift coefficients from 0.3 to 0.6 (untrimmed), and also indicated beneficial effects in the longitudinal and lateral static stability characteristics.

  12. Development of RTM and powder prepreg resins for subsonic aircraft primary structures

    NASA Technical Reports Server (NTRS)

    Woo, Edmund P.; Groleau, Michael R.; Bertram, James L.; Puckett, Paul M.; Maynard, Shawn J.

    1993-01-01

    Dow developed a thermoset resin which could be used to produce composites via the RTM process. The composites formed are useful at 200 F service temperatures after moisture saturation, and are tough systems that are suitable for subsonic aircraft primary structure. At NASA's request, Dow also developed a modified version of the RTM resin system which was suitable for use in producing powder prepreg. In the course of developing the RTM and powder versions of these resins, over 50 different new materials were produced and evaluated.

  13. 3D CFD modeling of subsonic and transonic flowing-gas DPALs with different pumping geometries

    NASA Astrophysics Data System (ADS)

    Yacoby, Eyal; Sadot, Oren; Barmashenko, Boris D.; Rosenwaks, Salman

    2015-10-01

    Three-dimensional computational fluid dynamics (3D CFD) modeling of subsonic (Mach number M ~ 0.2) and transonic (M ~ 0.9) diode pumped alkali lasers (DPALs), taking into account fluid dynamics and kinetic processes in the lasing medium is reported. The performance of these lasers is compared with that of supersonic (M ~ 2.7 for Cs and M ~ 2.4 for K) DPALs. The motivation for this study stems from the fact that subsonic and transonic DPALs require much simpler hardware than supersonic ones where supersonic nozzle, diffuser and high power mechanical pump (due to a drop in the gas total pressure in the nozzle) are required for continuous closed cycle operation. For Cs DPALs with 5 x 5 cm2 flow cross section pumped by large cross section (5 x 2 cm2) beam the maximum achievable power of supersonic devices is higher than that of the transonic and subsonic devices by only ~ 3% and ~ 10%, respectively. Thus in this case the supersonic operation mode has no substantial advantage over the transonic one. The main processes limiting the power of Cs supersonic DPALs are saturation of the D2 transition and large ~ 60% losses of alkali atoms due to ionization, whereas the influence of gas heating is negligible. For K transonic DPALs both the gas heating and ionization effects are shown to be unimportant. The maximum values of the power are higher than those in Cs transonic laser by ~ 11%. The power achieved in the supersonic and transonic K DPAL is higher than for the subsonic version, with the same resonator and K density at the inlet, by ~ 84% and ~ 27%, respectively, showing a considerable advantaged of the supersonic device over the transonic one. For pumping by rectangular beams of the same (5 x 2 cm2) cross section, comparison between end-pumping - where the laser beam and pump beam both propagate at along the same axis, and transverse-pumping - where they propagate perpendicularly to each other, shows that the output power and optical-to-optical efficiency are not

  14. Applicability of the independence principle to subsonic turbulent flow over a swept rearward-facing step

    NASA Technical Reports Server (NTRS)

    Selby, G. V.

    1983-01-01

    Prandtl (1946) has concluded that for yawed laminar incompressible flows the streamwise flow is independent of the spanwise flow. However, Ashkenas and Riddell (1955) have reported that for turbulent flow the 'independence principle' does not apply to yawed flat plates. On the other hand, it was also found that this principle may be applicable to many turbulent flows. As the sweep angle is increased, a sweep angle is reached which defines the interval over which the 'independence principle' is valid. The results obtained in the present investigation indicate the magnitude of the critical angle for subsonic turbulent flow over a swept rearward-facing step.

  15. Theoretical methods and design studies for NLF and HLFC swept wings at subsonic and supersonic speeds

    NASA Technical Reports Server (NTRS)

    Goradia, Suresh H.; Morgan, Harry L., Jr.

    1987-01-01

    Laminarization of the boundary layer on the surface of aircraft wings can be accomplished by the use of concepts such as Natural Laminar Flow (NLF), Laminar-Flow Control (LFC), and Hybrid Laminar-Flow Control (HLFC). Several integral boundary-layer methods were developed for the prediction of laminar, transition, and separating turbulent boundary layers. These methods were developed for use at either subsonic or supersonic speeds, have small computer execution times, and are simple to use. The theoretical equations and assumptions which form the basis of the boundary-layer method, are briefly outlined and the results of several correlation cases with exciting experimental data are presented.

  16. Preliminary measurements of velocity, density and total temperature fluctuations in compressible subsonic flow

    NASA Technical Reports Server (NTRS)

    Stainback, P. C.; Johnson, C. B.; Basnett, C. B.

    1983-01-01

    The heat transfer characteristics of a three-wire hot-wire probe operated with a constant temperature anemometer were investigated in the subsonic compressible flow regime. The sensitivity coefficients, with respect to velocity, density and total temperature, were measured and the results were used to calculate the velocity, density, and total temperature fluctuations in the test section of the Langley 0.3-m Transonic Cryogenic Tunnel (TCT). These results were extended to give estimates for fluctuations due to vorticity, sound, and entropy. In addition, attempts were made to determine the major source of disturbances in the 0.3-m TCT.

  17. Guidelines for Computing Longitudinal Dynamic Stability Characteristics of a Subsonic Transport

    NASA Technical Reports Server (NTRS)

    Thompson, Joseph R.; Frank, Neal T.; Murphy, Patrick C.

    2010-01-01

    A systematic study is presented to guide the selection of a numerical solution strategy for URANS computation of a subsonic transport configuration undergoing simulated forced oscillation about its pitch axis. Forced oscillation is central to the prevalent wind tunnel methodology for quantifying aircraft dynamic stability derivatives from force and moment coefficients, which is the ultimate goal for the computational simulations. Extensive computations are performed that lead in key insights of the critical numerical parameters affecting solution convergence. A preliminary linear harmonic analysis is included to demonstrate the potential of extracting dynamic stability derivatives from computational solutions.

  18. Trim and Structural Optimization of Subsonic Transport Wings Using Nonconventional Aeroelastic Tailoring

    NASA Technical Reports Server (NTRS)

    Stanford, Bret K.; Jutte, Christine V.

    2014-01-01

    Several minimum-mass aeroelastic optimization problems are solved to evaluate the effectiveness of a variety of novel tailoring schemes for subsonic transport wings. Aeroelastic strength and panel buckling constraints are imposed across a variety of trimmed maneuver loads. Tailoring with metallic thickness variations, functionally graded materials, composite laminates, tow steering, and distributed trailing edge control effectors are all found to provide reductions in structural wing mass with varying degrees of success. The question as to whether this wing mass reduction will offset the increased manufacturing cost is left unresolved for each case.

  19. Design and performance of a parachute for supersonic and subsonic recovery of an 800-lb payload

    SciTech Connect

    Peterson, C.W.; Waye, D.E.; Rollstin, L.R.; Holt, I.T.

    1986-01-01

    The design and development of a parachute system to recover an 800-lb test payload flying at both supersonic and subsonic speeds are presented. Performance data from full-scale flight tests for several parachute configurations were used to define an acceptable parachute system and to gain insight into which design parameters are most critical for supersonic parachute design. The suspension line length, canopy configuration, and forebody wake have a major effect upon parachute performance and stability. A tractor rocket was used to deploy this parachute system successfully at all deployment speeds.

  20. A conservative type-dependent full potential method for the treatment of supersonic flows with embedded subsonic regions

    NASA Technical Reports Server (NTRS)

    Shankar, V.; Szema, K.-Y.; Osher, S.

    1983-01-01

    A nonlinear method based on the full potential equation in conservation form, cast in an arbitrary coordinate system, has been developed to treat predominantly supersonic flows with embedded subsonic regions. This type of flow field occurs frequently near the fuselage-canopy junction area and wing leading edge regions for a moderately swept fighter configuration. The method uses the theory of characteristics to accurately monitor the type-dependent flow field. A conservative switching scheme is developed to transition from the supersonic marching algorithm to a subsonic relaxation procedure, and vice versa. An implicit approximate factorization scheme is employed to solve the finite-differenced equation. Results are shown for a few configurations, including a wing-body-wake realistic fighter model having embedded subsonic regions.

  1. Computer programs for estimating civil aircraft economics

    NASA Technical Reports Server (NTRS)

    Maddalon, D. V.; Molloy, J. K.; Neubawer, M. J.

    1980-01-01

    Computer programs for calculating airline direct operating cost, indirect operating cost, and return on investment were developed to provide a means for determining commercial aircraft life cycle cost and economic performance. A representative wide body subsonic jet aircraft was evaluated to illustrate use of the programs.

  2. A study to determine methods of improving the subsonic performance of a proposed Personnel Launch System (PLS) concept

    NASA Technical Reports Server (NTRS)

    Spencer, Bernard, Jr.; Fox, Charles H.; Huffman, Jarrett K.

    1995-01-01

    An investigation has been conducted in the Langley 7- by 10-Foot High Speed Wind Tunnel to determine the longitudinal and lateral directional aerodynamic characteristics of a series of personnel launch system concepts. This series of configurations evolved during an effort to improve the subsonic characteristics of a proposed lifting entry vehicle (designated the HL-20). The primary purpose of the overall investigation was to provide a vehicle concept which was inherently stable and trimable from entry to landing while examining methods of improving subsonic aerodynamic performance.

  3. Resource Letter ETC-1: extraterrestrial civilization.

    PubMed

    Kuiper, T B; Brin, G D

    1989-01-01

    This Resource Letter provides a guide to the literature about intelligent life beyond the human sphere of exploration. It offers a starting point for professionals and academics interested in participating in the debate about the existence of other technological civilizations or in the search for extraterrestrial intelligence (SETI). It can also serve as a reference for teaching. This Letter is not intended as an exhaustive bibliography, but several extensive bibliographies have been cited. The letter E after an item indicates elementary, nontechnical material of general interest to persons becoming informed in the field. Intermediate level material, of a somewhat more specialized nature, is indicated by the Letter I. The annotation A indicates advanced, technical material. An asterisk (*) precedes items to be included in an accompanying Reprint Book.

  4. DAC 22 High Speed Civil Transport Model

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Between tests, NASA research engineer Dave Hahne inspects a tenth-scale model of a supersonic transport model in the 30- by 60-Foot Tunnel at NASA Langley Research Center, Hampton, Virginia. The model is being used in support of NASA's High-Speed Research (HSR) program. Langley researchers are applying advance aerodynamic design methods to develop a wing leading-edge flap system which significantly improves low-speed fuel efficiency and reduces noise generated during takeoff operation. Langley is NASA's lead center for the agency's HSR program, aimed at developing technology to help U.S. industry compete in the rapidly expanding trans-oceanic transport market. A U.S. high-speed civil transport is expected to fly in about the year 2010. As envisioned, it would fly 300 passengers across the Pacific in about four hours at Mach 2.4 (approximately 1,600 mph/1950 kph) for a modest increase over business class fares.

  5. A comparison of the experimental subsonic pressure distributions about several bodies of revolution with pressure distributions computed by means of the linearized theory

    NASA Technical Reports Server (NTRS)

    Matthews, Clarence W

    1953-01-01

    An analysis is made of the effects of compressibility on the pressure coefficients about several bodies of revolution by comparing experimentally determined pressure coefficients with corresponding pressure coefficients calculated by the use of the linearized equations of compressible flow. The results show that the theoretical methods predict the subsonic pressure-coefficient changes over the central part of the body but do not predict the pressure-coefficient changes near the nose. Extrapolation of the linearized subsonic theory into the mixed subsonic-supersonic flow region fails to predict a rearward movement of the negative pressure-coefficient peak which occurs after the critical stream Mach number has been attained. Two equations developed from a consideration of the subsonic compressible flow about a prolate spheroid are shown to predict, approximately, the change with Mach number of the subsonic pressure coefficients for regular bodies of revolution of fineness ratio 6 or greater.

  6. Subsonic Aerodynamics of Spinning and Non-Spinning Type 200 Lightcraft: Progress Report

    NASA Astrophysics Data System (ADS)

    Kenoyer, David A.; Myrabo, Leik N.

    2010-05-01

    A combined experimental and numerical investigation of subsonic aerodynamics for Type 200 laser lightcraft is underway for both spinning and non-spinning cases. A 12.2 cm diameter aluminum model with a "closed" annular airbreathing inlet was fitted to a sting balance in RPI's 61 cm by 61 cm subsonic wind tunnel. Aerodynamic forces and moments were measured first for the non-spinning case vs. angle of attack, at several freestream flow velocities (e.g., 30, 45, and 60 m/s) to assess Reynolds number effects. The CFD analysis was performed for 0-180° angles of attack for a fixed coordinate system (i.e., non-spinning Type 200 model), and predictions compared favorably with the experimental data. In the near future, for the spinning case, a brushless electric motor has been installed to rotate the wind tunnel model at 3000 to 13,000 RPM; Magnus force effects upon the coefficients (Cd, Cl, and Cm) are expected to reveal interesting departures from the non-spinning database in forthcoming experiments.

  7. Natural Rolling Responses of a Delta Wing in Transonic and Subsonic Flows

    NASA Technical Reports Server (NTRS)

    Menzies, Margaret A.; Kandil, Osama A.

    1996-01-01

    The unsteady, three-dimensional, full Navier-Stokes (NS) equations and the Euler equations of rigid-body dynamics are sequentially solved to simulate the natural rolling response of slender delta wings of zero thickness at moderate to high angles of attack, to transonic and subsonic flows. The governing equations of fluid flow and dynamics of the present multi-disciplinary problem are solved using the time-accurate solution of the NS equations with the implicit, upwind, Roe flux-difference splitting, finite-volume scheme and a four-stage Runge-Kutta scheme, respectively. The main focus is to analyze the effect of Mach number and angle of attack on the leading edge vortices and their breakdown, the resultant rolling motion, and overall aerodynamic response of the wing. Three cases demonstrate the natural response of a 65 deg swept, cropped delta wing in a transonic flow with breakdown of the leading edge vortices and an 80 deg swept delta wing in a subsonic flow undergoing either damped or self-excited limit-cycle rolling oscillations as a function of angle of attack. Comparisons with an experimental investigation completes this study, validating the analysis and illustrating the complex details afforded by computational investigations.

  8. Calculation of subsonic and supersonic steady and unsteady aerodynamic forces using velocity potential aerodynamic elements

    NASA Technical Reports Server (NTRS)

    Haviland, J. K.; Yoo, Y. S.

    1976-01-01

    Expressions for calculation of subsonic and supersonic, steady and unsteady aerodynamic forces are derived, using the concept of aerodynamic elements applied to the downwash velocity potential method. Aerodynamic elements can be of arbitrary out of plane polygon shape, although numerical calculations are restricted to rectangular elements, and to the steady state case in the supersonic examples. It is suggested that the use of conforming, in place of rectangular elements, would give better results. Agreement with results for subsonic oscillating T tails is fair, but results do not converge as the number of collocation points is increased. This appears to be due to the form of expression used in the calculations. The methods derived are expected to facilitate automated flutter analysis on the computer. In particular, the aerodynamic element concept is consistent with finite element methods already used for structural analysis. The method is universal for the complete Mach number range, and, finally, the calculations can be arranged so that they do not have to be repeated completely for every reduced frequency.

  9. Effect of Initial Condition on Subsonic Jet Noise from Two Rectangular Nozzles

    NASA Technical Reports Server (NTRS)

    Zaman, K. B. M. Q.

    2012-01-01

    Differences in jet noise data from two small 8:1 aspect ratio nozzles are investigated experimentally. The interiors of the two nozzles are identical but one has a thin-lip at the exit while the has a perpendicular face at the exit (thick-lip). It is found that the thin-lip nozzle is substantially noisier throughout the subsonic Mach number range. As much as 5dB difference in OASPL is noticed around Mj =0.96. Hot-wire measurements are carried out for the characteristics of the exit boundary layer and, overall, the noise difference can be ascribed to differences in the boundary layer state. The boundary layer of the quieter (thick-lip) nozzle goes through transition around M(sub j) =0.25 and at higher M(sub j) it remains "nominally turbulent". In comparison, the boundary layer of the thin-lip nozzle is found to remain "nominally laminar". at high subsonic conditions. The nominally laminar state involves significantly larger turbulence intensities commensurate with the higher radiated noise.

  10. Electron collection theory for a D-region subsonic blunt electrostatic probe

    NASA Technical Reports Server (NTRS)

    Wai-Kwong Lai, T.

    1974-01-01

    Blunt probe theory for subsonic flow in a weakly ionized and collisional gas is reviewed, and an electron collection theory for the relatively unexplored case, Deybye length approximately 1, which occurs in the lower ionosphere (D-region), is developed. It is found that the dimensionless Debye length is no longer an electric field screening parameter, and the space charge field effect can be negelected. For ion collection, Hoult-Sonin theory is recognized as a correct description of the thin, ion density-perturbed layer adjacent the blunt probe surface. The large volume with electron density perturbed by a positively biased probe renders the usual thin boundary layer analysis inapplicable. Theories relating free stream conditions to the electron collection rate for both stationary and moving blunt probes are obtained. A model based on experimental nonlinear electron drift velocity data is proposed. For a subsonically moving probe, it is found that the perturbed region can be divided into four regions with distinct collection mechanisms.

  11. Subsonic stability and control flight test results of the Space Shuttle /tail cone off/

    NASA Technical Reports Server (NTRS)

    Cooke, D. R.

    1980-01-01

    The subsonic stability and control testing of the Space Shuttle Orbiter in its two test flights in the tailcone-off configuration is discussed, and test results are presented. Flight test maneuvers were designed to maximize the quality and quantity of stability and control data in the minimal time allotted using the Space Shuttle Functional Simulator and the Modified Maximum Likelihood Estimator (MMLE) programs, and coefficients were determined from standard sensor data sets using the MMLE, despite problems encountered in timing due to the different measurement systems used. Results are included for lateral directional and longitudinal maneuvers as well as the Space Shuttle aerodynamic data base obtained using the results of wind tunnel tests. The flight test data are found to permit greater confidence in the data base since the differences found are well within control system capability. It is suggested that the areas of major differences, including lateral directional data with open speedbrake, roll due to rudder and normal force due to elevon, be investigated in any further subsonic flight testing. Improvements in sensor data and data handling techniques for future orbital test flights are indicated.

  12. Method for the prediction of the installation aerodynamics of a propfan at subsonic speeds: User manual

    NASA Technical Reports Server (NTRS)

    Chandrasekaran, B.

    1986-01-01

    This document is the user's guide for the method developed earlier for predicting the slipstream wing interaction at subsonic speeds. The analysis involves a subsonic panel code (HESS code) modified to handle the propeller onset flow. The propfan slipstream effects are superimposed on the normal flow boundary condition and are applied over the surface washed by the slipstream. The effects of the propeller slipstream are to increase the axial induced velocity, tangential velocity, and a total pressure rise in the wake of the propeller. Principles based on blade performance theory, momentum theory, and vortex theory were used to evaluate the slipstream effects. The code can be applied to any arbitrary three dimensional geometry, expressed in the form of HESS input format. The code can handle a propeller alone configuration or a propeller/nacelle/airframe configuration, operating up to high subcritical Mach numbers over a range of angles of attack. Inclusion of a viscous modelling is briefly outlined. Wind tunnel results/theory comparisons are included as examples for the application of the code to a generic supercritical wing/overwing Nacelle with a powered propfan. A sample input/output listing is provided.

  13. On fluttering modes for aircraft wing model in subsonic air flow.

    PubMed

    Shubov, Marianna A

    2014-12-08

    The paper deals with unstable aeroelastic modes for aircraft wing model in subsonic, incompressible, inviscid air flow. In recent author's papers asymptotic, spectral and stability analysis of the model has been carried out. The model is governed by a system of two coupled integrodifferential equations and a two-parameter family of boundary conditions modelling action of self-straining actuators. The Laplace transform of the solution is given in terms of the 'generalized resolvent operator', which is a meromorphic operator-valued function of the spectral parameter λ, whose poles are called the aeroelastic modes. The residues at these poles are constructed from the corresponding mode shapes. The spectral characteristics of the model are asymptotically close to the ones of a simpler system, which is called the reduced model. For the reduced model, the following result is shown: for each value of subsonic speed, there exists a radius such that all aeroelastic modes located outside the circle of this radius centred at zero are stable. Unstable modes, whose number is always finite, can occur only inside this 'circle of instability'. Explicit estimate of the 'instability radius' in terms of model parameters is given.

  14. On fluttering modes for aircraft wing model in subsonic air flow

    PubMed Central

    Shubov, Marianna A.

    2014-01-01

    The paper deals with unstable aeroelastic modes for aircraft wing model in subsonic, incompressible, inviscid air flow. In recent author’s papers asymptotic, spectral and stability analysis of the model has been carried out. The model is governed by a system of two coupled integrodifferential equations and a two-parameter family of boundary conditions modelling action of self-straining actuators. The Laplace transform of the solution is given in terms of the ‘generalized resolvent operator’, which is a meromorphic operator-valued function of the spectral parameter λ, whose poles are called the aeroelastic modes. The residues at these poles are constructed from the corresponding mode shapes. The spectral characteristics of the model are asymptotically close to the ones of a simpler system, which is called the reduced model. For the reduced model, the following result is shown: for each value of subsonic speed, there exists a radius such that all aeroelastic modes located outside the circle of this radius centred at zero are stable. Unstable modes, whose number is always finite, can occur only inside this ‘circle of instability’. Explicit estimate of the ‘instability radius’ in terms of model parameters is given. PMID:25484610

  15. Multi-Mission Earth Vehicle Subsonic Dynamic Stability Testing and Analyses

    NASA Technical Reports Server (NTRS)

    Glaab, Louis J.; Fremaux, C. Michael

    2013-01-01

    Multi-Mission Earth Entry Vehicles (MMEEVs) are blunt-body vehicles designed with the purpose of transporting payloads from outer space to the surface of the Earth. To achieve high-reliability and minimum weight, MMEEVs avoid use of limited-reliability systems, such as parachutes, retro-rockets, and reaction control systems and rely on the natural aerodynamic stability of the vehicle throughout the Entry, Descent, and Landing (EDL) phase of flight. The Multi-Mission Systems Analysis for Planetary Entry (M-SAPE) parametric design tool is used to facilitate the design of MMEEVs for an array of missions and develop and visualize the trade space. Testing in NASA Langley?s Vertical Spin Tunnel (VST) was conducted to significantly improve M-SAPE?s subsonic aerodynamic models. Vehicle size and shape can be driven by entry flight path angle and speed, thermal protection system performance, terminal velocity limitations, payload mass and density, among other design parameters. The objectives of the VST testing were to define usable subsonic center of gravity limits, and aerodynamic parameters for 6-degree-of-freedom (6-DOF) simulations, for a range of MMEEV designs. The range of MMEEVs tested was from 1.8m down to 1.2m diameter. A backshell extender provided the ability to test a design with a much larger payload for the 1.2m MMEEV.

  16. Source characterization of a subsonic jet by using near-field acoustical holography.

    PubMed

    Lee, Moohyung; Bolton, J Stuart

    2007-02-01

    In the present study, patch near-field acoustical holography was used in conjunction with a multireference, cross-spectral sound pressure measurement to visualize the sound field emitted by a subsonic jet and to predict its farfield radiation pattern. A strategy for microphone array design is described that accounts for the low spatial coherence of aeroacoustic sources and for microphone self-noise resulting from entrained flow near the jet. In the experiments, a 0.8-cm-diameter burner was used to produce a subsonic, turbulent jet with a Mach number of 0.26. Six fixed, linear arrays holding eight reference microphones apiece were disposed circumferentially around the jet, and a circular array holding sixteen, equally spaced field microphones was traversed along the jet axis to measure the sound field on a 30-cm-diameter cylindrical surface enclosing the jet. The results revealed that the jet could be modeled as a combination of eleven uncorrelated dipole-, quadrupole-, and octupole-like sources, and the contribution of each source type to the total radiated sound power could be identified. Both the total sound field reconstructed in a three-dimensional space and the farfield radiation directivity obtained by using the latter model were successfully validated by comparisons to directly measured results.

  17. The Langley 14- by 22-Foot Subsonic Tunnel: Description, Flow Characteristics, and Guide for Users

    NASA Technical Reports Server (NTRS)

    Gentry, Garl L., Jr.; Quinto, P. Frank; Gatlin, Gregory M.; Applin, Zachary T.

    1990-01-01

    The Langley 14- by 22-foot Subsonic Tunnel is a closed circuit, single-return atmospheric wind tunnel with a test section that can be operated in a variety of configurations (closed, slotted, partially open, and open). The closed test section configuration is 14.5 ft high by 21.75 ft wide and 50 ft long with a maximum speed of about 338 ft/sec. The open test section configuration has a maximum speed of about 270 ft/sec, and is formed by raising the ceiling and walls, to form a floor-only configuration. The tunnel may be configured with a moving-belt ground plane and a floor boundary-layer removal system at the entrance to the test section for ground effect testing. In addition, the tunnel had a two-component laser velocimeter, a frequency modulated (FM) tape system for dynamic data acquisition, flow visualization equipment, and acoustic testing capabilities. Users of the 14- by 22-foot Subsonic Tunnel are provided with information required for planning of experimental investigations including test hardware and model support systems.

  18. Validation of a reduced-order jet model for subsonic and underexpanded hydrogen jets

    DOE PAGES

    Li, Xuefang; Hecht, Ethan S.; Christopher, David M.

    2016-01-01

    Much effort has been made to model hydrogen releases from leaks during potential failures of hydrogen storage systems. A reduced-order jet model can be used to quickly characterize these flows, with low computational cost. Notional nozzle models are often used to avoid modeling the complex shock structures produced by the underexpanded jets by determining an “effective” source to produce the observed downstream trends. In our work, the mean hydrogen concentration fields were measured in a series of subsonic and underexpanded jets using a planar laser Rayleigh scattering system. Furthermore, we compared the experimental data to a reduced order jet modelmore » for subsonic flows and a notional nozzle model coupled to the jet model for underexpanded jets. The values of some key model parameters were determined by comparisons with the experimental data. Finally, the coupled model was also validated against hydrogen concentrations measurements for 100 and 200 bar hydrogen jets with the predictions agreeing well with data in the literature.« less

  19. Acoustic radiation damping of flat rectangular plates subjected to subsonic flows

    NASA Technical Reports Server (NTRS)

    Lyle, Karen Heitman

    1993-01-01

    The acoustic radiation damping for various isotropic and laminated composite plates and semi-infinite strips subjected to a uniform, subsonic and steady flow has been predicted. The predictions are based on the linear vibration of a flat plate. The fluid loading is characterized as the perturbation pressure derived from the linearized Bernoulli and continuity equations. Parameters varied in the analysis include Mach number, mode number and plate size, aspect ratio and mass. The predictions are compared with existing theoretical results and experimental data. The analytical results show that the fluid loading can significantly affect realistic plate responses. Generally, graphite/epoxy and carbon/carbon plates have higher acoustic radiation damping values than similar aluminum plates, except near plate divergence conditions resulting from aeroelastic instability. Universal curves are presented where the acoustic radiation damping normalized by the mass ratio is a linear function of the reduced frequency. A separate curve is required for each Mach number and plate aspect ratio. In addition, acoustic radiation damping values can be greater than or equal to the structural component of the modal critical damping ratio (assumed as 0.01) for the higher subsonic Mach numbers. New experimental data were acquired for comparison with the analytical results.

  20. Subsonic tests of an all-flush-pressure-orifice air data system

    NASA Technical Reports Server (NTRS)

    Larson, T. J.; Siemers, P. M., III

    1981-01-01

    The use of an all-flush-pressure-orifice array as a subsonic air data system was evaluated in flight and wind tunnel tests. Two orifice configurations were investigated. Both used orifices arranged in a cruciform pattern on the airplane nose. One configuration also used orifices on the sides of the fuselage for a source of static pressure. The all-nose-orifice configuration was similar to the shuttle entry air data system (SEADS). The flight data were obtained with a KC-135A airplane. The wind tunnel data were acquired with a 0.035-scale model of the KC-135A airplane. With proper calibration, several orifices on the vertical centerline of the vehicle's nose were found to be satisfactory for the determination of total pressure and angle of attack. Angle of sideslip could be accurately determined from pressure measurements made on the horizontal centerline of the aircraft. Orifice pairs were also found that provided pressure ratio relationships suitable for the determination of Mach number. The accuracy that can be expected for the air data determined with SEADS during subsonic orbiter flight is indicated.

  1. Defense Support to Civil Authorities: Surveying Institutional Challenges

    DTIC Science & Technology

    2009-05-01

    around cities like New Orleans, Biloxi, and Baton Rouge had little extra capacity before the storm; now they had their own problems.” 85 Though DoD...by MAJ Anthony T. Murtha United States Army School of Advanced Military Studies United States Army Command and General Staff College Fort ...21-05-2009 2. REPORT TYPE Monograph 3. DATES COVERED (From - To) JUL 2008 – MAY 2009 4. TITLE AND SUBTITLE Defense Support to Civil Authorities

  2. Civil Applications For New V/STOL and STOL Aircraft

    NASA Technical Reports Server (NTRS)

    Albers, James A.; Zuk, John

    1990-01-01

    New designs offer benefits in congested urban areas and remote regions. Report explores potential uses in civil aviation of advanced rotorcraft, vertical/short-takeoff-and-landing (V/STOL) aircraft, and short-takeoff-and-landing (STOL) aircraft. Future opportunities overcome formidable geographic barriers and lack of major airport facilities, bringing fast, flexible transportation to remote areas. Aircraft relieves congestion at airports in densely populated areas by utilizing pads and short runways without interfering with large-air-carrier traffic.

  3. Space Civil Engineering option - A progress report

    NASA Technical Reports Server (NTRS)

    Criswell, Marvin E.; Sadeh, Willy Z.

    1992-01-01

    Space Civil Engineering is an emerging engineering discipline that focuses on extending and expanding Civil Engineering to the development, operation, and maintenance of infrastructures on celestial bodies. Space Civil Engineering is presently being developed as a new discipline within the Department of Civil Engineering at Colorado State University and with support of the NASA Space Grant College Program. Academic programs geared toward creating Space Civil Engineering Options at both undergraduate and graduate levels are being formulated. Basic ideas and concepts and the current status of the curriculum in the Space Civil Engineering Option primarily at the undergraduate level are presented.

  4. Suggestions for Popularizing Civil Aviation

    NASA Technical Reports Server (NTRS)

    1926-01-01

    The public generally is taking very little interest in the progress of Civil Aviation, and the time has come to educate the public in aeronautics and to make them realize the far-reaching importance of air transport. Briefly, the whole problem resolves itself into discovering and applying means for bringing some of the many aspects and effects of civil aviation into the everyday lives of the public. The report suggests three principal groups of methods: (1) Bring aviation into daily contact with the public. (2) Bring the public into daily contact with aviation. (3) General publicity.

  5. AST Critical Propulsion and Noise Reduction Technologies for Future Commercial Subsonic Engines Area of Interest 1.0: Reliable and Affordable Control Systems

    NASA Technical Reports Server (NTRS)

    Myers, William; Winter, Steve

    2006-01-01

    The General Electric Reliable and Affordable Controls effort under the NASA Advanced Subsonic Technology (AST) Program has designed, fabricated, and tested advanced controls hardware and software to reduce emissions and improve engine safety and reliability. The original effort consisted of four elements: 1) a Hydraulic Multiplexer; 2) Active Combustor Control; 3) a Variable Displacement Vane Pump (VDVP); and 4) Intelligent Engine Control. The VDVP and Intelligent Engine Control elements were cancelled due to funding constraints and are reported here only to the state they progressed. The Hydraulic Multiplexing element developed and tested a prototype which improves reliability by combining the functionality of up to 16 solenoids and servo-valves into one component with a single electrically powered force motor. The Active Combustor Control element developed intelligent staging and control strategies for low emission combustors. This included development and tests of a Controlled Pressure Fuel Nozzle for fuel sequencing, a Fuel Multiplexer for individual fuel cup metering, and model-based control logic. Both the Hydraulic Multiplexer and Controlled Pressure Fuel Nozzle system were cleared for engine test. The Fuel Multiplexer was cleared for combustor rig test which must be followed by an engine test to achieve full maturation.

  6. Advanced wing design survivability testing and results

    NASA Technical Reports Server (NTRS)

    Bruno, J.; Tobias, M.

    1992-01-01

    Composite wings on current operational aircraft are conservatively designed to account for stress/strain concentrations, and to assure specified damage tolerance. The technology that can lead to improved composite wing structures and associated structural efficiency is to increase design ultimate strain levels beyond their current limit of 3500 to 4000 micro-in/in to 6000 micro-in/in without sacrificing structural integrity, durability, damage tolerance, or survivability. Grumman, under the sponsorship of the Naval Air Development Center (NADC), has developed a high-strain composite wing design for a subsonic aircraft wing using novel and innovative design concepts and manufacturing methods, while maintaining a state-of-the-art fiber/resin system. The current advanced wing design effort addressed a tactical subsonic aircraft wing using previously developed, high-strain wing design concepts in conjunction with newer/emerging fiber and polymer matrix composite (PMC) materials to achieve the same goals, while reducing complexity. Two categories of advanced PMC materials were evaluated: toughened thermosets; and engineered thermoplastics. Advanced PMC materials offer the technological opportunity to take maximum advantage of improved material properties, physical characteristics, and tailorability to increase performance and survivability over current composite structure. Damage tolerance and survivability to various threats, in addition to structural integrity and durability, were key technical issues addressed during this study, and evaluated through test. This paper focuses on the live-fire testing, and the results performed to experimentally evaluate the survivability of the advanced wing design.

  7. Wing pressure distributions from subsonic tests of a high-wing transport model. [in the Langley 14- by 22-Foot Subsonic Wind Tunnel

    NASA Technical Reports Server (NTRS)

    Applin, Zachary T.; Gentry, Garl L., Jr.; Takallu, M. A.

    1995-01-01

    A wind tunnel investigation was conducted on a generic, high-wing transport model in the Langley 14- by 22-Foot Subsonic Tunnel. This report contains pressure data that document effects of various model configurations and free-stream conditions on wing pressure distributions. The untwisted wing incorporated a full-span, leading-edge Krueger flap and a part-span, double-slotted trailing-edge flap system. The trailing-edge flap was tested at four different deflection angles (20 deg, 30 deg, 40 deg, and 60 deg). Four wing configurations were tested: cruise, flaps only, Krueger flap only, and high lift (Krueger flap and flaps deployed). Tests were conducted at free-stream dynamic pressures of 20 psf to 60 psf with corresponding chord Reynolds numbers of 1.22 x 10(exp 6) to 2.11 x 10(exp 6) and Mach numbers of 0.12 to 0.20. The angles of attack presented range from 0 deg to 20 deg and were determined by wing configuration. The angle of sideslip ranged from minus 20 deg to 20 deg. In general, pressure distributions were relatively insensitive to free-stream speed with exceptions primarily at high angles of attack or high flap deflections. Increasing trailing-edge Krueger flap significantly reduced peak suction pressures and steep gradients on the wing at high angles of attack. Installation of the empennage had no effect on wing pressure distributions. Unpowered engine nacelles reduced suction pressures on the wing and the flaps.

  8. Homeland Security and Civil Liberties

    DTIC Science & Technology

    2004-06-01

    liberties, immigration policy, privacy issues, first amendment rights, and the balance of executive and judicial power in relation to civil liberties and...homeland security is extraordinarily complex with immigration policy, criminal law, privacy, First Amendment , and separation of powers dimensions

  9. Getting the Civil War Right

    ERIC Educational Resources Information Center

    Loewen, James W.

    2011-01-01

    William Faulkner famously wrote, "The past is never dead. It's not even past." He would not be surprised to learn that Americans, 150 years after the Civil War began, are still getting it wrong. Did America's most divisive war start over slavery or states' rights? The author says that too many people--including educators--get it wrong. The author…

  10. Civil Engineering Technology Program Guide.

    ERIC Educational Resources Information Center

    Georgia Univ., Athens. Dept. of Vocational Education.

    This program guide presents civil engineering technology curriculum for technical institutes in Georgia. The general information section contains the following: purpose and objectives; program description, including admissions, typical job titles, and accreditation and certification; and curriculum model, including standard curriculum sequence and…

  11. Computers, Costs, and Civil Liberties

    ERIC Educational Resources Information Center

    Kelley, Verne R.; Weston, Hanna B.

    1975-01-01

    The need to control costs has led many state mental health systems to set up automated data banks in which a patient's name is directly linked with his record. Many consider this a primary threat to confidentiality and civil liberties. (Author)

  12. Civil law problems and morbidity

    PubMed Central

    Pleasence, P; Balmer, N; Buck, A; O'Grady, A; Genn, H

    2004-01-01

    Study objective: In the United Kingdom, recognition of the links between social and health problems has led to government initiatives such as health action zones. The principles of civil law apply to many types of social problem, and the civil justice system provides one means through which they can be tackled. However, little research has been undertaken into the particular links between problems to which civil legal principles and processes can be applied and morbidity. This study examines these links, and the role of legal advice and services in preventing ill health. Design: This study examined survey respondents' self reports of longstanding illness/disability and experience of 18 problems to which legal principles can be applied. Setting: A random national survey conducted across England and Wales. Participants: 5611 adults drawn from 3348 residential households. Main results: Significant associations were found between illness/disability and 13 of the problem types. Moreover, experience of greater numbers of problems increased the likelihood of reported illness/disability. In attempting to resolve problems respondents' health also frequently suffered. Conclusions: This study highlights the contribution that public legal education and legal advice can make to the promotion of public health, and the importance of further integration of health and civil justice initiatives through health action zones, community legal service partnerships, etc, to further this end. PMID:15194714

  13. Primary Sources Enliven Civil War

    ERIC Educational Resources Information Center

    Robelen, Erik W.

    2011-01-01

    Today, a growing number of teachers are moving beyond the textbook in teaching about the war, and U.S. history more broadly. Teachers are digging directly into primary sources and harnessing technology, all in an attempt to help students better understand the past and bring it to life. Doing so may be especially important with the Civil War,…

  14. Promoting Civil Discourse on Campus

    ERIC Educational Resources Information Center

    Bornstein, Rita

    2010-01-01

    During the past several decades, off campus and on, much of the discourse on controversial issues has been personal, vicious, and divisive. On the national scene, politics has become permeated with incivility. It now appears that Americans have been naive about their ability and willingness to engage in civil discourse and compromise. How can…

  15. The Civil War and Iowa.

    ERIC Educational Resources Information Center

    Gore, Deborah, Ed.

    1987-01-01

    This journal issue explores Iowa's participation in the U.S. Civil War and primarily focuses on what happened to the men, women, and children who remained at home. A number of social, political, and economic changes are examined, including: (1) the increased responsibilities of women and children; (2) the growth of abolitionism; (3) the role of…

  16. The Last Day of Civilization.

    ERIC Educational Resources Information Center

    Jacobson, Willard J.

    1982-01-01

    A narrative account of what might occur the first day of a nuclear war is interspersed with facts about the nuclear arms race and about the destructive power of weapons already stockpiled in the United States and the Soviet Union. A plea is made for preserving civilization from such a catastrophe. (PP)

  17. Extraterrestrial civilizations: Problems of their evolution

    NASA Technical Reports Server (NTRS)

    Leskov, L. V.

    1987-01-01

    The problem of finding extraterrestrial civilizations and establishing contact with them is directly related to the problem of their evolution. Possible patterns in this evolution and the stages in the evolution of extraterrestrial civilizations are examined.

  18. LOW SUBSONIC PRESSURE DISTRIBUTIONS ON THREE RIGID WINGS SIMULATING PARAGLIDERS WITH VARIED CANOPY CURVATURE AND LEADING-EDGE SWEEP

    DTIC Science & Technology

    An investigation was made in the Langley 7- by 10-foot transonic tunnel to determine the subsonic pressure distribution of three paraglider models...through an angle-of-attack range from 0 to 74 degrees. Three rigid meta models simulated a 45 degrees basic flat planform paraglider with leading-edge

  19. An NACA Vane-Type Angle-of-Attack Indicator for use at Subsonic and Supersonic Speeds

    NASA Technical Reports Server (NTRS)

    Mitchell, Jesse L.; Peck, Robert F.

    1949-01-01

    A vane-type angle-of-attack indicator suitable for measurements at both subsonic and supersonic speeds has been developed by the National Advisory Committee for Aeronautics. A brief history is given of the development, and a wind-tunnel calibration of the indicator is presented, together with a discussion of the corrections to be applied to the indicated readings.

  20. Three-dimensional aerodynamic analysis of a subsonic transport high-lift configuration and comparisons with wind-tunnel test results

    NASA Technical Reports Server (NTRS)

    Edge, D. Christian; Perkins, John N.

    1995-01-01

    The sizing and efficiency of an aircraft is largely determined by the performance of its high-lift system. Subsonic civil transports most often use deployable multi-element airfoils to achieve the maximum-lift requirements for landing, as well as the high lift-to-drag ratios for take-off. However, these systems produce very complex flow fields which are not fully understood by the scientific community. In order to compete in today's market place, aircraft manufacturers will have to design better high-lift systems. Therefore, a more thorough understanding of the flows associated with these systems is desired. Flight and wind-tunnel experiments have been conducted on NASA Langley's B737-100 research aircraft to obtain detailed full-scale flow measurements on a multi-element high-lift system at various flight conditions. As part of this effort, computational aerodynamic tools are being used to provide preliminary flow-field information for instrumentation development, and to provide additional insight during the data analysis and interpretation process. The purpose of this paper is to demonstrate the ability and usefulness of a three-dimensional low-order potential flow solver, PMARC, by comparing computational results with data obtained from 1/8 scale wind-tunnel tests. Overall, correlation of experimental and computational data reveals that the panel method is able to predict reasonably well the pressures of the aircraft's multi-element wing at several spanwise stations. PMARC's versatility and usefulness is also demonstrated by accurately predicting inviscid three-dimensional flow features for several intricate geometrical regions.

  1. Climate Change and Civil Violence

    NASA Astrophysics Data System (ADS)

    van der Vink, G.; Plancherel, Y.; Hennet, C.; Jones, K. D.; Abdullah, A.; Bradshaw, J.; Dee, S.; Deprez, A.; Pasenello, M.; Plaza-Jennings, E.; Roseman, D.; Sopher, P.; Sung, E.

    2009-05-01

    The manifestations of climate change can result in humanitarian impacts that reverse progress in poverty- reduction, create shortages of food and resources, lead to migration, and ultimately result in civil violence and conflict. Within the continent of Africa, we have found that environmentally-related variables are either the cause or the confounding factor for over 80% of the civil violence events during the last 10 years. Using predictive climate models and land-use data, we are able to identify populations in Africa that are likely to experience the most severe climate-related shocks. Through geospatial analysis, we are able to overlay these areas of high risk with assessments of both the local population's resiliency and the region's capacity to respond to climate shocks should they occur. The net result of the analysis is the identification of locations that are becoming particularly vulnerable to future civil violence events (vulnerability hotspots) as a result of the manifestations of climate change. For each population group, over 600 social, economic, political, and environmental indicators are integrated statistically to measures the vulnerability of African populations to environmental change. The indicator time-series are filtered for data availability and redundancy, broadly ordered into four categories (social, political, economic and environmental), standardized and normalized. Within each category, the dominant modes of variability are isolated by principal component analysis and the loadings of each component for each variable are used to devise composite index scores. Comparisons of past vulnerability with known environmentally-related conflicts demonstrates the role that such vulnerability hotspot maps can play in evaluating both the potential for, and the significance of, environmentally-related civil violence events. Furthermore, the analysis reveals the major variables that are responsible for the population's vulnerability and therefore

  2. Model-based feedback control of subsonic cavity flows: Control design

    NASA Astrophysics Data System (ADS)

    Yuan, Xin

    In this dissertation, we present and discuss development, implementation, and experimental results of reduced-order model based feedback control of subsonic cavity flows. Model based feedback control of subsonic flows have been studied and implemented by the flow control group at the Collaborative Center of Control Science (CCCS) at the Ohio State University (OSU). The team, composed of researchers from the departments of Electrical Engineering and Mechanical Engineering at the Ohio State, the Air Force Research Laboratory, and NASA Glenn Research Center, possesses synergistic capabilities in all of the required multidisciplinary areas of experimental data acquisition, computational flow simulation, low dimensional modeling, controller design, and experimental validation. The goal of the CCCS effort is to develop tools and methodologies for the use of closed-loop aerodynamic flow control to manipulate the flow over maneuvering air vehicles. The problem chosen for the initial study by the CCCS flow team is control of the resonant noise generated by subsonic flow past an open cavity. This phenomenon is characterized by a strong coupling between the flow dynamics and the flow-induced acoustic field that can lead to self-sustained resonance. Two approaches towards model development have been studied in this dissertation. One aims at representing the physical properties of the system by dynamical models in transfer function forms, referred to as the physics-based linear model in this dissertation. The other approach we have followed is based on proper orthogonal decomposition (POD) and Galerkin projection methods involving the flow governing equations, which is referred to as the nonlinear model or Galerkin model in the dissertation. Each model mentioned above can be further divided into two types: model derived from numerical simulation data and model derived from real time experimental data. Different types of feedback controllers have been designed for corresponding

  3. 13 CFR 302.20 - Civil rights.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Civil rights. 302.20 Section 302... TERMS AND CONDITIONS FOR INVESTMENT ASSISTANCE § 302.20 Civil rights. (a) Discrimination is prohibited... 601 of Title VI of the Civil Rights Act of 1964, as amended (42 U.S.C. 2000d et seq.)...

  4. 39 CFR 233.12 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Civil penalties. 233.12 Section 233.12 Postal... Civil penalties. False representation and lottery orders— (a) Issuance. Pursuant to 39 U.S.C. 3005, the... be liable to the United States for a civil penalty in an amount not to exceed $11,000 for each...

  5. 49 CFR 228.21 - Civil penalty.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Civil penalty. 228.21 Section 228.21..., DEPARTMENT OF TRANSPORTATION HOURS OF SERVICE OF RAILROAD EMPLOYEES Records and Reporting § 228.21 Civil... requirement is subject to a civil penalty of at least $650 and not more than $25,000 per violation,...

  6. 32 CFR 310.46 - Civil actions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 2 2011-07-01 2011-07-01 false Civil actions. 310.46 Section 310.46 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) PRIVACY PROGRAM DOD PRIVACY PROGRAM Privacy Act Violations § 310.46 Civil actions. An individual may file a civil...

  7. 14 CFR 1212.800 - Civil remedies.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 5 2011-01-01 2010-01-01 true Civil remedies. 1212.800 Section 1212.800... Comply With Requirements of This Part § 1212.800 Civil remedies. Failure to comply with the requirements of the Privacy Act and this part could subject NASA to civil suit under the provisions of 5...

  8. 34 CFR 303.424 - Civil action.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 2 2011-07-01 2010-07-01 true Civil action. 303.424 Section 303.424 Education... Civil action. Any party aggrieved by the findings and decision regarding an administrative complaint has the right to bring a civil action in State or Federal court under section 639(a)(1) of the...

  9. 34 CFR 300.516 - Civil action.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 2 2011-07-01 2010-07-01 true Civil action. 300.516 Section 300.516 Education... DISABILITIES Procedural Safeguards Due Process Procedures for Parents and Children § 300.516 Civil action. (a... aggrieved by the findings and decision under § 300.514(b), has the right to bring a civil action...

  10. 12 CFR 215.11 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 2 2011-01-01 2011-01-01 false Civil penalties. 215.11 Section 215.11 Banks... OFFICERS, DIRECTORS, AND PRINCIPAL SHAREHOLDERS OF MEMBER BANKS (REGULATION O) § 215.11 Civil penalties... subject to civil penalties as specified in section 29 of the Federal Reserve Act (12 U.S.C. 504)....

  11. 49 CFR 233.11 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Civil penalties. 233.11 Section 233.11..., DEPARTMENT OF TRANSPORTATION SIGNAL SYSTEMS REPORTING REQUIREMENTS § 233.11 Civil penalties. Any person (an... subject to a civil penalty of at least $650 and not more than $25,000 per violation, except...

  12. 10 CFR 824.4 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Civil penalties. 824.4 Section 824.4 Energy DEPARTMENT OF ENERGY PROCEDURAL RULES FOR THE ASSESSMENT OF CIVIL PENALTIES FOR CLASSIFIED INFORMATION SECURITY VIOLATIONS § 824.4 Civil penalties. (a) Any person who violates a classified information...

  13. 43 CFR 3163.2 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Civil penalties. 3163.2 Section 3163.2..., Assessments, and Penalties § 3163.2 Civil penalties. (a) Whenever an operating rights owner or operator, as... for a civil penalty of up to $500 per violation for each day such violation continues, dating from...

  14. 33 CFR 401.102 - Civil penalty.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Civil penalty. 401.102 Section... TRANSPORTATION SEAWAY REGULATIONS AND RULES Penalties-Violations of Seaway Regulations § 401.102 Civil penalty. (a) A person, as described in § 401.101(b), who violates a regulation is liable to a civil penalty...

  15. 32 CFR 643.114 - Civil disturbances.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 4 2011-07-01 2011-07-01 false Civil disturbances. 643.114 Section 643.114... ESTATE Additional Authority of Commanders § 643.114 Civil disturbances. Without reference to higher... facilities during civil disturbance for not more than 30 days to the National Guard and to municipal,...

  16. 22 CFR 127.10 - Civil penalty.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Civil penalty. 127.10 Section 127.10 Foreign... Civil penalty. (a) The Assistant Secretary of State for Political-Military Affairs is authorized to impose a civil penalty in an amount not to exceed that authorized by 22 U.S.C. 2778, 2779a and 2780...

  17. 49 CFR 218.9 - Civil penalty.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Civil penalty. 218.9 Section 218.9 Transportation... TRANSPORTATION RAILROAD OPERATING PRACTICES General § 218.9 Civil penalty. Any person (an entity of any type... requirement of this part or causes the violation of any such requirement is subject to a civil penalty of...

  18. 10 CFR 110.64 - Civil penalty.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Civil penalty. 110.64 Section 110.64 Energy NUCLEAR... Enforcement § 110.64 Civil penalty. (a) In response to a violation, the Commission may institute a proceeding to impose a civil penalty under section 234 of the Atomic Energy Act by issuing a notice to...

  19. 31 CFR 1010.820 - Civil penalty.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Civil penalty. 1010.820 Section 1010... § 1010.820 Civil penalty. (a) For any willful violation, committed on or before October 12, 1984, of any... participates in the violation, a civil penalty not to exceed $1,000. (b) For any willful violation...

  20. 50 CFR 300.40 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 9 2011-10-01 2011-10-01 false Civil penalties. 300.40 Section 300.40... South Pacific Tuna Fisheries § 300.40 Civil penalties. The procedures of 15 CFR part 904 apply to the assessment of civil penalties, except as modified by the requirements of section 8 of the Act....

  1. 12 CFR 229.21 - Civil liability.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 3 2011-01-01 2011-01-01 false Civil liability. 229.21 Section 229.21 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM... Availability Policies § 229.21 Civil liability. (a) Civil liability. A bank that fails to comply with...

  2. 43 CFR 10.12 - Civil penalties.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... REPATRIATION REGULATIONS Human Remains, Funerary Objects, Sacred Objects, or Objects of Cultural Patrimony in Museums and Federal Collections § 10.12 Civil penalties. (a) The Secretary's authority to assess civil penalties. The Secretary is authorized by section 9 of the Act to assess civil penalties on any museum...

  3. 43 CFR 10.12 - Civil penalties.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... REPATRIATION REGULATIONS Human Remains, Funerary Objects, Sacred Objects, or Objects of Cultural Patrimony in Museums and Federal Collections § 10.12 Civil penalties. (a) The Secretary's authority to assess civil penalties. The Secretary is authorized by section 9 of the Act to assess civil penalties on any museum...

  4. 43 CFR 10.12 - Civil penalties.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... REPATRIATION REGULATIONS Human Remains, Funerary Objects, Sacred Objects, or Objects of Cultural Patrimony in Museums and Federal Collections § 10.12 Civil penalties. (a) The Secretary's authority to assess civil penalties. The Secretary is authorized by section 9 of the Act to assess civil penalties on any museum...

  5. 43 CFR 10.12 - Civil penalties.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... REPATRIATION REGULATIONS Human Remains, Funerary Objects, Sacred Objects, or Objects of Cultural Patrimony in Museums and Federal Collections § 10.12 Civil penalties. (a) The Secretary's authority to assess civil penalties. The Secretary is authorized by section 9 of the Act to assess civil penalties on any museum...

  6. 43 CFR 10.12 - Civil penalties.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... REPATRIATION REGULATIONS Human Remains, Funerary Objects, Sacred Objects, or Objects of Cultural Patrimony in Museums and Federal Collections § 10.12 Civil penalties. (a) The Secretary's authority to assess civil penalties. The Secretary is authorized by section 9 of the Act to assess civil penalties on any museum...

  7. Civil Highway Curriculum Evaluation. Final Report.

    ERIC Educational Resources Information Center

    Prindiville, Gerald

    The purpose of the civil highway curriculum evaluation was to provide data for course review and revision. As civil engineering is a rapidly changing occupational field, it is important to determine what skills are currently essential for civil highway technicians. The associate degree programs in the four Wisconsin technical institutes offering…

  8. 50 CFR 401.22 - Civil rights.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Civil rights. 401.22 Section 401.22..., DEVELOPMENT AND ENHANCEMENT § 401.22 Civil rights. Each application for Federal assistance, grant-in-aid award... Assisted Programs of the Civil Rights Act of 1964 and with the Secretary's regulations...

  9. 28 CFR 33.52 - Civil rights.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 28 Judicial Administration 1 2013-07-01 2013-07-01 false Civil rights. 33.52 Section 33.52... Block Grants Additional Requirements § 33.52 Civil rights. The Justice Assistance Act provides that “no... the provisions of title VI of the Civil Rights Act of 1964; section 504 of the Rehabilitation Act...

  10. 7 CFR 3560.2 - Civil rights.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 15 2012-01-01 2012-01-01 false Civil rights. 3560.2 Section 3560.2 Agriculture... DIRECT MULTI-FAMILY HOUSING LOANS AND GRANTS General Provisions and Definitions § 3560.2 Civil rights. (a... prohibition under Title VI of the Civil Rights Act of 1964, 42 U.S.C. 2000d and Title VI regulations...

  11. 28 CFR 65.52 - Civil rights.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 28 Judicial Administration 2 2012-07-01 2012-07-01 false Civil rights. 65.52 Section 65.52... Additional Requirements § 65.52 Civil rights. The Act provides that “no person in any state shall on the... funds under the Act are also subject to the provisions of title VI of the Civil Rights Act of...

  12. 7 CFR 3550.3 - Civil rights.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 15 2012-01-01 2012-01-01 false Civil rights. 3550.3 Section 3550.3 Agriculture... DIRECT SINGLE FAMILY HOUSING LOANS AND GRANTS General § 3550.3 Civil rights. RHS will administer its... amended by Executive Order 12259, as applicable. The civil rights compliance requirements for RHS are in...

  13. 28 CFR 65.52 - Civil rights.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 28 Judicial Administration 2 2014-07-01 2014-07-01 false Civil rights. 65.52 Section 65.52... Additional Requirements § 65.52 Civil rights. The Act provides that “no person in any state shall on the... funds under the Act are also subject to the provisions of title VI of the Civil Rights Act of...

  14. 50 CFR 82.20 - Civil rights.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 9 2013-10-01 2013-10-01 false Civil rights. 82.20 Section 82.20 Wildlife... (MARINE MAMMAL PROTECTION ACT OF 1972) Administration § 82.20 Civil rights. Each cooperative agreement... Civil Rights Act of 1964, 42 U.S.C. 2000d-2000d-4, and with the Secretary's regulations...

  15. 7 CFR 761.3 - Civil rights.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 7 2014-01-01 2014-01-01 false Civil rights. 761.3 Section 761.3 Agriculture... SPECIAL PROGRAMS FARM LOAN PROGRAMS; GENERAL PROGRAM ADMINISTRATION General Provisions § 761.3 Civil rights. Part 15d of this title contains applicable regulations pertaining to civil rights and filing...

  16. 28 CFR 65.52 - Civil rights.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Civil rights. 65.52 Section 65.52... Additional Requirements § 65.52 Civil rights. The Act provides that “no person in any state shall on the... funds under the Act are also subject to the provisions of title VI of the Civil Rights Act of...

  17. 50 CFR 82.20 - Civil rights.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Civil rights. 82.20 Section 82.20 Wildlife... (MARINE MAMMAL PROTECTION ACT OF 1972) Administration § 82.20 Civil rights. Each cooperative agreement... Civil Rights Act of 1964, 42 U.S.C. 2000d-2000d-4, and with the Secretary's regulations...

  18. 7 CFR 1709.18 - Civil rights.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 11 2013-01-01 2013-01-01 false Civil rights. 1709.18 Section 1709.18 Agriculture... ASSISTANCE TO HIGH ENERGY COST COMMUNITIES General Requirements § 1709.18 Civil rights. This program will be administered in accordance with applicable Federal Civil Rights Law. All grants made under this subpart...

  19. 7 CFR 761.3 - Civil rights.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 7 2011-01-01 2011-01-01 false Civil rights. 761.3 Section 761.3 Agriculture... SPECIAL PROGRAMS GENERAL PROGRAM ADMINISTRATION General Provisions § 761.3 Civil rights. Part 15d of this title contains applicable regulations pertaining to civil rights and filing of discrimination...

  20. 28 CFR 33.52 - Civil rights.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 28 Judicial Administration 1 2014-07-01 2014-07-01 false Civil rights. 33.52 Section 33.52... Block Grants Additional Requirements § 33.52 Civil rights. The Justice Assistance Act provides that “no... the provisions of title VI of the Civil Rights Act of 1964; section 504 of the Rehabilitation Act...

  1. The Transformed Civil Rights Data Collection (CRDC)

    ERIC Educational Resources Information Center

    Office for Civil Rights, US Department of Education, 2012

    2012-01-01

    Since 1968, the Civil Rights Data Collection (CRDC) has collected data on key education and civil rights issues in our nation's public schools for use by the Department of Education's Office for Civil Rights (OCR), other Department offices, other federal agencies, and by policymakers and researchers outside of the Department. The CRDC has…

  2. 28 CFR 65.52 - Civil rights.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 28 Judicial Administration 2 2013-07-01 2013-07-01 false Civil rights. 65.52 Section 65.52... Additional Requirements § 65.52 Civil rights. The Act provides that “no person in any state shall on the... funds under the Act are also subject to the provisions of title VI of the Civil Rights Act of...

  3. 7 CFR 3555.3 - Civil rights.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Civil rights. 3555.3 Section 3555.3 Agriculture... GUARANTEED RURAL HOUSING PROGRAM (Eff. 9-1-14) General § 3555.3 Civil rights. Rural Development, lenders, and.... Rural Development's civil rights compliance requirements are provided in 7 CFR part 1901, subpart E....

  4. 30 CFR 880.16 - Civil rights.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Civil rights. 880.16 Section 880.16 Mineral... LAND RECLAMATION MINE FIRE CONTROL § 880.16 Civil rights. State and local authorities shall comply with Title VI of the Civil Rights Act of 1964 (Pub. L. 88-352) and all requirements imposed by or pursuant...

  5. 7 CFR 1709.18 - Civil rights.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 11 2012-01-01 2012-01-01 false Civil rights. 1709.18 Section 1709.18 Agriculture... ASSISTANCE TO HIGH ENERGY COST COMMUNITIES General Requirements § 1709.18 Civil rights. This program will be administered in accordance with applicable Federal Civil Rights Law. All grants made under this subpart...

  6. 30 CFR 880.16 - Civil rights.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Civil rights. 880.16 Section 880.16 Mineral... LAND RECLAMATION MINE FIRE CONTROL § 880.16 Civil rights. State and local authorities shall comply with Title VI of the Civil Rights Act of 1964 (Pub. L. 88-352) and all requirements imposed by or pursuant...

  7. 50 CFR 82.20 - Civil rights.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false Civil rights. 82.20 Section 82.20 Wildlife... (MARINE MAMMAL PROTECTION ACT OF 1972) Administration § 82.20 Civil rights. Each cooperative agreement... Civil Rights Act of 1964, 42 U.S.C. 2000d-2000d-4, and with the Secretary's regulations...

  8. 50 CFR 401.22 - Civil rights.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 11 2014-10-01 2014-10-01 false Civil rights. 401.22 Section 401.22..., DEVELOPMENT AND ENHANCEMENT § 401.22 Civil rights. Each application for Federal assistance, grant-in-aid award... Assisted Programs of the Civil Rights Act of 1964 and with the Secretary's regulations...

  9. 7 CFR 3550.3 - Civil rights.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Civil rights. 3550.3 Section 3550.3 Agriculture... DIRECT SINGLE FAMILY HOUSING LOANS AND GRANTS General § 3550.3 Civil rights. RHS will administer its... amended by Executive Order 12259, as applicable. The civil rights compliance requirements for RHS are in...

  10. 30 CFR 880.16 - Civil rights.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Civil rights. 880.16 Section 880.16 Mineral... LAND RECLAMATION MINE FIRE CONTROL § 880.16 Civil rights. State and local authorities shall comply with Title VI of the Civil Rights Act of 1964 (Pub. L. 88-352) and all requirements imposed by or pursuant...

  11. 7 CFR 3550.3 - Civil rights.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Civil rights. 3550.3 Section 3550.3 Agriculture... DIRECT SINGLE FAMILY HOUSING LOANS AND GRANTS General § 3550.3 Civil rights. RHS will administer its... amended by Executive Order 12259, as applicable. The civil rights compliance requirements for RHS are in...

  12. 28 CFR 33.52 - Civil rights.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 28 Judicial Administration 1 2012-07-01 2012-07-01 false Civil rights. 33.52 Section 33.52... Block Grants Additional Requirements § 33.52 Civil rights. The Justice Assistance Act provides that “no... the provisions of title VI of the Civil Rights Act of 1964; section 504 of the Rehabilitation Act...

  13. 30 CFR 880.16 - Civil rights.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Civil rights. 880.16 Section 880.16 Mineral... LAND RECLAMATION MINE FIRE CONTROL § 880.16 Civil rights. State and local authorities shall comply with Title VI of the Civil Rights Act of 1964 (Pub. L. 88-352) and all requirements imposed by or pursuant...

  14. 50 CFR 401.22 - Civil rights.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 9 2011-10-01 2011-10-01 false Civil rights. 401.22 Section 401.22..., DEVELOPMENT AND ENHANCEMENT § 401.22 Civil rights. Each application for Federal assistance, grant-in-aid award... Assisted Programs of the Civil Rights Act of 1964 and with the Secretary's regulations...

  15. 7 CFR 761.3 - Civil rights.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Civil rights. 761.3 Section 761.3 Agriculture... SPECIAL PROGRAMS GENERAL PROGRAM ADMINISTRATION General Provisions § 761.3 Civil rights. Part 15d of this title contains applicable regulations pertaining to civil rights and filing of discrimination...

  16. 28 CFR 65.52 - Civil rights.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 28 Judicial Administration 2 2011-07-01 2011-07-01 false Civil rights. 65.52 Section 65.52... Additional Requirements § 65.52 Civil rights. The Act provides that “no person in any state shall on the... funds under the Act are also subject to the provisions of title VI of the Civil Rights Act of...

  17. 13 CFR 302.20 - Civil rights.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 13 Business Credit and Assistance 1 2013-01-01 2013-01-01 false Civil rights. 302.20 Section 302... TERMS AND CONDITIONS FOR INVESTMENT ASSISTANCE § 302.20 Civil rights. (a) Discrimination is prohibited... 601 of Title VI of the Civil Rights Act of 1964, as amended (42 U.S.C. 2000d et seq.)...

  18. 13 CFR 302.20 - Civil rights.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 13 Business Credit and Assistance 1 2014-01-01 2014-01-01 false Civil rights. 302.20 Section 302... TERMS AND CONDITIONS FOR INVESTMENT ASSISTANCE § 302.20 Civil rights. (a) Discrimination is prohibited... 601 of Title VI of the Civil Rights Act of 1964, as amended (42 U.S.C. 2000d et seq.)...

  19. 7 CFR 1709.18 - Civil rights.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 11 2014-01-01 2014-01-01 false Civil rights. 1709.18 Section 1709.18 Agriculture... ASSISTANCE TO HIGH ENERGY COST COMMUNITIES General Requirements § 1709.18 Civil rights. This program will be administered in accordance with applicable Federal Civil Rights Law. All grants made under this subpart...

  20. 7 CFR 3550.3 - Civil rights.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 15 2011-01-01 2011-01-01 false Civil rights. 3550.3 Section 3550.3 Agriculture... DIRECT SINGLE FAMILY HOUSING LOANS AND GRANTS General § 3550.3 Civil rights. RHS will administer its... amended by Executive Order 12259, as applicable. The civil rights compliance requirements for RHS are in...