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Sample records for acquisition vehicle entry

  1. Beale Air Force Base, Perimeter Acquisition Vehicle Entry PhasedArray Warning ...

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

    Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Satellite Communications Terminal, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  2. Beale Air Force Base, Perimeter Acquisition Vehicle Entry PhasedArray Warning ...

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

    Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Electric Substation, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  3. Beale Air Force Base, Perimeter Acquisition Vehicle Entry PhasedArray Warning ...

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

    Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Civil Engineering Storage Building, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  4. Beale Air Force Base, Perimeter Acquisition Vehicle Entry PhasedArray Warning ...

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

    Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Techinical Equipment Building, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  5. Beale Air Force Base, Perimeter Acquisition Vehicle Entry PhasedArray Warning ...

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

    Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Microwave Equipment Building, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  6. Orbit re-entry experiment vehicle development

    NASA Astrophysics Data System (ADS)

    Yamamoto, Masataka; Yamawaki, Kouji; Akimoto, Toshio; Murakami, Atsushi; Inaba, Motoyuki; Kaneko, Yutaka; Shimoda, Takayuki; Ishii, Yasuo; Izumi, Tatsushi; Kawano, Isao

    1992-08-01

    An overview of the Orbital Re-entry Experiment (OREX) vehicle development, including detail design, analyses on the overall system, guidance and control, propulsion, and data acquisition systems is presented. The outline of the experiment vehicle is shown. OREX flight is analyzed and the splash down point variance ellipse is shown. Vehicle body aerodynamic characteristics were analyzed and validated by supersonic wind tunnel and dynamically balanced wind tunnel tests. Analyses on onboard equipment environmental resistance, controllability from on orbit to re-entry phases and navigation and guidance of the space plane were conducted. It was confirmed that there was no problem on the guidance and control system. Review on the propellant volume and analyses on the propulsion system performance, propulsion system heat exchanger performance, and thruster and piping system temperature were conducted and possibility of hard starting of the 150 N hydrazine thruster was noticed. RF (Radio Frequency) link analyses were conducted around Tanegashima, Ogasawara, and the splash down area and prospect of continuously acquiring good link margin for 300 seconds was obtained. Semi unitized structure of truncated cone shape with main body made of aluminum alloy, which has application record for rockets, laid with skin, stringers, and frames was employed for the structure. Data acquisition systems for tracking and operation, including those at Tanegashima, Ogasawara, Christmas, down range ship, and airplane tracking stations were studied.

  7. Interior view Beale Air Force Base, Perimeter Acquisition Vehicle ...

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

    Interior view - Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Satellite Communications Terminal, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  8. Looking north Beale Air Force Base, Perimeter Acquisition Vehicle ...

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

    Looking north - Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Electric Substation, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  9. Thermal Soak Analysis of Earth Entry Vehicles

    NASA Technical Reports Server (NTRS)

    Agrawal, Parul; Sepka, Steven A.; Aliaga, Jose F.; Venkatapathy, Ethiraj; Samareh, Jamshid A.

    2012-01-01

    The Multi-Mission Earth Entry Vehicle project is developing an integrated tool called Multi Mission System Analysis for Planetary Entry Descent and Landing that will provide key technology solutions including mass sizing, aerodynamics, aerothermodynamics, and thermal and structural analysis for any given sample return mission. Thermal soak analysis and temperature predictions of various components including the payload container of the entry vehicle are part of the solution that this tool will offer to mission designers. The present paper focuses on the thermal soak analysis of an entry vehicle design based on the Mars Sample Return entry vehicle geometry and discusses a technical approach to develop parametric models for thermal soak analysis that will be integrated into the tool.

  10. Thermal Analysis Methods For Earth Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Amundsen, Ruth M.; Dec, John A.; Lindell, Michael C.

    2000-01-01

    Thermal analysis of a vehicle designed to return samples from another planet, such as the Earth Entry vehicle for the Mars Sample Return mission, presents several unique challenges. The Earth Entry Vehicle (EEV) must contain Martian material samples after they have been collected and protect them from the high heating rates of entry into the Earth's atmosphere. This requirement necessitates inclusion of detailed thermal analysis early in the design of the vehicle. This paper will describe the challenges and solutions for a preliminary thermal analysis of an Earth Entry Vehicle. The aeroheating on the vehicle during entry would be the main driver for the thermal behavior, and is a complex function of time, spatial position on the vehicle, vehicle temperature, and trajectory parameters. Thus, the thermal analysis must be closely tied to the aeroheating analysis in order to make accurate predictions. Also, the thermal analysis must account for the material response of the ablative thermal protection system (TPS). For the exo-atmospheric portion of the mission, the thermal analysis must include the orbital radiation fluxes on the surfaces. The thermal behavior must also be used to predict the structural response of the vehicle (the thermal stress and strains) and whether they remain within the capability of the materials. Thus, the thermal analysis requires ties to the three-dimensional geometry, the aeroheating analysis, the material response analysis, the orbital analysis, and the structural analysis. The goal of this paper is to describe to what degree that has been achieved.

  11. Shadowgraph Images of Re-entry Vehicles

    NASA Technical Reports Server (NTRS)

    1960-01-01

    These four shadowgraph images represent early re-entry vehicle concepts. A shadowgraph is a process that makes visible the disturbances that occur in a fluid flow at high velocity, in which light passing through a flowing fluid is refracted by the density gradients in the fluid resulting in bright and dark areas on a screen placed behind the fluid.H. Julian Allen pioneered and developed the Blunt Body Theory which made possible the heat shield designs that were embodied in the Mercury, Gemini and Apollo space capsules, enabling astronauts to survive the firey re-entry into Earth's atmosphere. A blunt body produces a shockwave in front of the vehicle--visible in the photo--that actually shields the vehicle from excessive heating. As a result, blunt body vehicles can stay cooler than pointy, low drag vehicles.

  12. Entry Guidance for the Reusable Launch Vehicle

    NASA Technical Reports Server (NTRS)

    Lu, Ping

    1999-01-01

    The X-33 Advanced Technology Demonstrator is a half-scale prototype developed to test the key technologies needed for a full-scale single-stage reusable launch vehicle (RLV). The X-33 is a suborbital vehicle that will be launched vertically, and land horizontally. The goals of this research were to develop an alternate entry guidance scheme for the X-33 in parallel to the actual X-33 entry guidance algorithms, provide comparative and complementary study, and identify potential new ways to improve entry guidance performance. Toward these goals, the nominal entry trajectory is defined by a piecewise linear drag-acceleration-versus-energy profile, which is in turn obtained by the solution of a semi-analytical parameter optimization problem. The closed-loop guidance is accomplished by tracking the nominal drag profile with primarily bank-angle modulation on-board. The bank-angle is commanded by a single full-envelope nonlinear trajectory control law. Near the end of the entry flight, the guidance logic is switched to heading control in order to meet strict conditions at the terminal area energy management interface. Two methods, one on ground-track control and the other on heading control, were proposed and examined for this phase of entry guidance where lateral control is emphasized. Trajectory dispersion studies were performed to evaluate the effectiveness of the entry guidance algorithms against a number of uncertainties including those in propulsion system, atmospheric properties, winds, aerodynamics, and propellant loading. Finally, a new trajectory-regulation method is introduced at the end as a promising precision entry guidance method. The guidance principle is very different and preliminary application in X-33 entry guidance simulation showed high precision that is difficult to achieve by existing methods.

  13. Earth Entry Vehicle for Mars Sample Return

    NASA Technical Reports Server (NTRS)

    Mitcheltree, R. A.; Braun, R. D.; Hughes. S. J.; Simonsen, L. C.

    2000-01-01

    The driving requirement for design of a Mars Sample return mission is assuring containment of the returned samples. The impact of this requirement on developmental costs, mass allocation, and design approach of the Earth Entry Vehicle is significant. A simple Earth entry vehicle is described which can meet these requirements and safely transport the Mars Sample Return mission's sample through the Earth's atmosphere to a recoverable location on the surface. Detailed analysis and test are combined with probabilistic risk assessment to design this entirely passive concept that circumvents the potential failure modes of a parachute terminal descent system. The design also possesses features that mitigate other risks during the entry, descent, landing and recovery phases. The results of a full-scale drop test are summarized.

  14. Re-entry vehicle dynamics

    NASA Astrophysics Data System (ADS)

    Regan, F. J.

    The present book has the objective to provide the practicing engineer with a senior-level introduction to the dynamics of reentry vehicles. A description is provided of an atmospheric model, and the earth's form and gravity field are examined, taking into account basic atmospheric relationships, the development of an analytic atmospheric model, a simple atmospheric model for closed-form solutions, the geocentric position vector, the deviation of the vertical, the earth's radius, and a computer program for calculating the gravitational acceleration. Force equations are considered along with aspects of Keplerian motion, reentry body particle mechanics, moment equations, axis transformations, a flowfield description, moment equations in a constant density atmosphere, boost trajectories, angular motion during the Keplerian phase, angular motion during reentry, and the inverse method. Attention is also given to first-order linear differential equations with variable coefficients, ring laser gyros and pendulous accelerometers, the calculation of the real roots of a polynomial, quaternions.

  15. Anatomy of an entry vehicle experiment

    NASA Technical Reports Server (NTRS)

    Eide, D. G.; Wurster, K. E.; Helms, V. T.; Ashby, G. C.

    1981-01-01

    The anatomy and evolution of a simple small-scale unmanned entry vehicle is described that is delivered to orbit by the shuttle and entered into the atmosphere from orbit to acquire flight data to improve our knowledge of boundary-layer behavior and evaluate advanced thermal protection systems. The anatomy of the experiment includes the justification for the experiments, instrumentation, configuration, material, and operational needs, and the translation of these needs into a configuration, weight statement, aerodynamics, program cost, and trajectory. Candidates for new instrumentation development are also identified for nonintrusive measurements of the boundary-layer properties.

  16. In Situ Magnetohydrodynamic Energy Generation for Planetary Entry Vehicles

    NASA Astrophysics Data System (ADS)

    Ali, H. K.; Braun, R. D.

    2014-06-01

    This work aims to study the suitability of multi-pass entry trajectories for harnessing of vehicle kinetic energy through magnetohydrodynamic power generation from the high temperature entry plasma. Potential mission configurations are analyzed.

  17. Inflatable Emergency Atmospheric-Entry Vehicles

    NASA Technical Reports Server (NTRS)

    Jones, Jack; Hall, Jeffrey; Wu, Jiunn Jeng

    2004-01-01

    In response to the loss of seven astronauts in the Space Shuttle Columbia disaster, large, lightweight, inflatable atmospheric- entry vehicles have been proposed as means of emergency descent and landing for persons who must abandon a spacecraft that is about to reenter the atmosphere and has been determined to be unable to land safely. Such a vehicle would act as an atmospheric decelerator at supersonic speed in the upper atmosphere, and a smaller, central astronaut pod could then separate at lower altitudes and parachute separately to Earth. Astronaut-rescue systems that have been considered previously have been massive, and the cost of designing them has exceeded the cost of fabrication of a space shuttle. In contrast, an inflatable emergency-landing vehicle according to the proposal would have a mass between 100 and 200 kg, could be stored in a volume of approximately 0.2 to 0.4 cu m, and could likely be designed and built much less expensively. When fully inflated, the escape vehicle behaves as a large balloon parachute, or ballute. Due to very low mass-per-surface area, a large radius, and a large coefficient of drag, ballutes decelerate at much higher altitudes and with much lower heating rates than the space shuttle. Although the space shuttle atmospheric reentry results in surface temperatures of about 1,600 C, ballutes can be designed for maximum temperatures below 600 C. This allows ballutes to be fabricated with lightweight ZYLON(Registered TradeMark) or polybenzoxazole (PBO), or equivalent.

  18. 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.

  19. 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.

  20. Thermal Analysis Methods for an Earth Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Amundsen, Ruth M.; Dec, John A.; Lindell, Michael C.

    2000-01-01

    Thermal analysis of a vehicle designed to return samples from another planet, such as the Earth Entry vehicle for the Mars Sample Return mission, presents several unique challenges. The Earth Entry Vehicle (EEV) must contain Martian material samples after they have been collected and protect them from the high heating rates of entry into the Earth's atmosphere. This requirement necessitates inclusion of detailed thermal analysis early in the design of the vehicle. This paper will describe the challenges and solutions for a preliminary thermal analysis of an Earth Entry Vehicle. The aeroheatina on the vehicle during entry would be the main driver for the thermal behavior. and is a complex function of time, spatial position on the vehicle, vehicle temperature, and trajectory parameters. Thus. the thermal analysis must be closely tied to the aeroheating analysis in order to make accurate predictions. Also, the thermal analysis must account for the material response of the ablative thermal protection system TPS. For the exo-atmospheric portion of the mission, the thermal analysis must include the orbital radiation fluxes on the surfaces. The thermal behavior must also be used to predict the structural response of the vehicle (the thermal stress and strains) and whether they remain within the capability of the materials. Thus, the thermal analysis requires ties to the three-dimensional geometry, the aeroheating analysis, the material response analysis, the orbital analysis. and the structural analysis. The goal of this paper is to describe to what degree that has been achieved.

  1. Optimization of entry-vehicle shapes during conceptual design

    NASA Astrophysics Data System (ADS)

    Dirkx, D.; Mooij, E.

    2014-01-01

    During the conceptual design of a re-entry vehicle, the vehicle shape and geometry can be varied and its impact on performance can be evaluated. In this study, the shape optimization of two classes of vehicles has been studied: a capsule and a winged vehicle. Their aerodynamic characteristics were analyzed using local-inclination methods, automatically selected per vehicle segment. Entry trajectories down to Mach 3 were calculated assuming trimmed conditions. For the winged vehicle, which has both a body flap and elevons, a guidance algorithm to track a reference heat-rate was used. Multi-objective particle swarm optimization was used to optimize the shape using objectives related to mass, volume and range. The optimizations show a large variation in vehicle performance over the explored parameter space. Areas of very strong non-linearity are observed in the direct neighborhood of the two-dimensional Pareto fronts. This indicates the need for robust exploration of the influence of vehicle shapes on system performance during engineering trade-offs, which are performed during conceptual design. A number of important aspects of the influence of vehicle behavior on the Pareto fronts are observed and discussed. There is a nearly complete convergence to narrow-wing solutions for the winged vehicle. Also, it is found that imposing pitch-stability for the winged vehicle at all angles of attack results in vehicle shapes which require upward control surface deflections during the majority of the entry.

  2. An Entry Flight Controls Analysis for a Reusable Launch Vehicle

    NASA Technical Reports Server (NTRS)

    Calhoun, Philip

    2000-01-01

    The NASA Langley Research Center has been performing studies to address the feasibility of various single-stage to orbit concepts for use by NASA and the commercial launch industry to provide a lower cost access to space. Some work on the conceptual design of a typical lifting body concept vehicle, designated VentureStar(sup TM) has been conducted in cooperation with the Lockheed Martin Skunk Works. This paper will address the results of a preliminary flight controls assessment of this vehicle concept during the atmospheric entry phase of flight. The work includes control analysis from hypersonic flight at the atmospheric entry through supersonic speeds to final approach and landing at subsonic conditions. The requirements of the flight control effectors are determined over the full range of entry vehicle Mach number conditions. The analysis was performed for a typical maximum crossrange entry trajectory utilizing angle of attack to limit entry heating and providing for energy management, and bank angle to modulation of the lift vector to provide downrange and crossrange capability to fly the vehicle to a specified landing site. Sensitivity of the vehicle open and closed loop characteristics to CG location, control surface mixing strategy and wind gusts are included in the results. An alternative control surface mixing strategy utilizing a reverse aileron technique demonstrated a significant reduction in RCS torque and fuel required to perform bank maneuvers during entry. The results of the control analysis revealed challenges for an early vehicle configuration in the areas of hypersonic pitch trim and subsonic longitudinal controllability.

  3. Entry Vehicle Control System Design for the Mars Smart Lander

    NASA Technical Reports Server (NTRS)

    Calhoun, Philip C.; Queen, Eric M.

    2002-01-01

    The NASA Langley Research Center, in cooperation with the Jet Propulsion Laboratory, participated in a preliminary design study of the Entry, Descent and Landing phase for the Mars Smart Lander Project. This concept utilizes advances in Guidance, Navigation and Control technology to significantly reduce uncertainty in the vehicle landed location on the Mars surface. A candidate entry vehicle controller based on the Reaction Control System controller for the Apollo Lunar Excursion Module digital autopilot is proposed for use in the entry vehicle attitude control. A slight modification to the phase plane controller is used to reduce jet-firing chattering while maintaining good control response for the Martian entry probe application. The controller performance is demonstrated in a six-degree-of-freedom simulation with representative aerodynamics.

  4. Overview of the Mars Sample Return Earth Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Dillman, Robert; Corliss, James

    2008-01-01

    NASA's Mars Sample Return (MSR) project will bring Mars surface and atmosphere samples back to Earth for detailed examination. Langley Research Center's MSR Earth Entry Vehicle (EEV) is a core part of the mission, protecting the sample container during atmospheric entry, descent, and landing. Planetary protection requirements demand a higher reliability from the EEV than for any previous planetary entry vehicle. An overview of the EEV design and preliminary analysis is presented, with a follow-on discussion of recommended future design trade studies to be performed over the next several years in support of an MSR launch in 2018 or 2020. Planned topics include vehicle size for impact protection of a range of sample container sizes, outer mold line changes to achieve surface sterilization during re-entry, micrometeoroid protection, aerodynamic stability, thermal protection, and structural materials selection.

  5. 10 CFR 490.302 - Vehicle acquisition mandate schedule.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ....302 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Fuel Provider Vehicle Acquisition Mandate § 490.302 Vehicle acquisition mandate schedule. (a..., when the mandated acquisition percentage of alternative fuel vehicles is applied to the number of...

  6. 10 CFR 490.302 - Vehicle acquisition mandate schedule.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ....302 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Fuel Provider Vehicle Acquisition Mandate § 490.302 Vehicle acquisition mandate schedule. (a..., when the mandated acquisition percentage of alternative fuel vehicles is applied to the number of...

  7. 10 CFR 490.302 - Vehicle acquisition mandate schedule.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ....302 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Fuel Provider Vehicle Acquisition Mandate § 490.302 Vehicle acquisition mandate schedule. (a..., when the mandated acquisition percentage of alternative fuel vehicles is applied to the number of...

  8. 10 CFR 490.302 - Vehicle acquisition mandate schedule.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ....302 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Fuel Provider Vehicle Acquisition Mandate § 490.302 Vehicle acquisition mandate schedule. (a..., when the mandated acquisition percentage of alternative fuel vehicles is applied to the number of...

  9. 10 CFR 490.302 - Vehicle acquisition mandate schedule.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ....302 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Fuel Provider Vehicle Acquisition Mandate § 490.302 Vehicle acquisition mandate schedule. (a..., when the mandated acquisition percentage of alternative fuel vehicles is applied to the number of...

  10. Hypersonic aerodynamics and entry-maneuver: Aerothermodynamic interactions for two lifting entry vehicles

    NASA Technical Reports Server (NTRS)

    Arrington, J. P.; Woods, W. C.

    1972-01-01

    The longitudinal, directional, and lateral static stability and control characteristics of a delta lifting body and a delta-wing body were obtained at a Mach number of 20 in helium for operational Reynolds numbers over an angle-of-attack range of -4 deg to 55 deg. The aerodynamic characteristics of the wing body were then evaluated in an entry study to examine the effects of vehicle performance on the aerothermodynamic parameters associated with constant and variable angle-of-attack modes for a 1500-n. mi. cross range. The experimental results indicated that the vehicles were stable, except for neutral directional stability for the wing-body shape, and could be trimmed over the operational angle-of-attack range; however, the wing-body vehicle had adverse yaw due to roll control. This roll-yaw coupling was not examined for the lifting body. The trajectory analysis indicated that a 17-percent decrease in performance required little change in the constant angle-of-attack entry mode and, in turn, resulted in a small decrease in the total heat load. For the pitch-modulated entry, the performance decrease required the pitch maneuver to begin earlier during entry and to last longer in order to meet the 1500-n. mi. cross range without a major heating penalty. The performance reduction also had little effect on the maximum laminar radiation equilibrium temperature over a major portion of the lower surface of the wing-body vehicle regardless of the entry mode.

  11. Control Surface Seals Investigated for Re- Entry Vehicles

    NASA Technical Reports Server (NTRS)

    Dunlap, Patrick H.; Steinetz, Bruce M.

    2003-01-01

    Re-entry vehicles generally use control surfaces (e.g., rudders, body flaps, and elevons) to steer or guide them as they pass into and through the Earth s atmosphere. High temperature seals are required around control surfaces both along hinge lines and in areas where control surface edges seal against the vehicle body to limit hot gas ingestion and the transfer of heat to underlying low-temperature structures. Working with the NASA Johnson Space Center, the Seals Team at the NASA Glenn Research Center completed a series of tests on the baseline seal design for the rudder/fin control surface interfaces of the X-38 vehicle. This seal application was chosen as a case study to evaluate a currently available control surface seal design for applications in future re-entry vehicles. The structures of the rudder/fin assembly and its associated seals are shown in the following illustration.

  12. Re-Entry Mission Analysis of the Advanced Re-entry Vehicle (ARV)

    NASA Astrophysics Data System (ADS)

    Bonetti, D.; Haya Ramos, R.; Strauch, H.; Bottacini, M.

    2011-08-01

    This paper presents the results of the DEIMOS Space S.L.U. Re-entry Mission Analysis activities obtained in the frame of the Phase A up to PRR milestone of the Advanced Re-entry Vehicle (ARV) ESA project leaded by ASTRIUM. Results presented show how the trajectory and the vehicle design are strictly related and how a feasible and robust solution can be efficiently obtained by considering since the beginning several constraints limiting the design. The process implemented combines the design of key vehicle and trajectory parameters. Once the vehicle design parameters and the conditions at the EIP are fixed, the Mission Analysis is completed by the definition of the optimal trajectory from the deorbiting to the EIP that allow the correct targeting of the EIP conditions but also a safe separation of the different modules and the correct targeting of the desired landing site.

  13. Re-Entry Mission Analysis Of The Advanced Re-Entry Vehicle (ARV)

    NASA Astrophysics Data System (ADS)

    Bonetti, Davide; Haya Ramos, Rodrigo; Strauch, Hans; Bottacini, Massimiliano

    2011-05-01

    This paper presents the results of the DEIMOS Space S.L.U. Re-entry Mission Analysis activities obtained in the frame of the Phase A up to PRR milestone of the Advanced Re-entry Vehicle (ARV) ESA project leaded by ASTRIUM. Results presented show how the trajectory and the vehicle design are strictly related and how a feasible and robust solution can be efficiently obtained by considering since the beginning several constraints limiting the design. The process implemented combines the design of key vehicle and trajectory parameters. Once the vehicle design parameters and the conditions at the EIP are fixed, the Mission Analysis is completed by the definition of the optimal trajectory from the de- orbiting to the EIP that allow the correct targeting of the EIP conditions but also a safe separation of the different modules and the correct targeting of the desired landing site.

  14. An Earth Entry Vehicle For Returning Samples From Mars

    NASA Technical Reports Server (NTRS)

    Mitcheltree, R.; Hughes, S.; Dillman, R.; Teter, J.

    2001-01-01

    The driving requirement for design of a Mars Sample return mission is assuring containment of the returned samples. The impact of this requirement on developmental costs, mass allocation, and design approach of the Earth Entry Vehicle is significant. A simple Earth entry vehicle is described which can meet these requirements and safely transport the Mars Sample Return mission's sample through the Earth's atmosphere to a recoverable location on the surface. Detailed analysis and test are combined with probabilistic risk assessment to design this entirely passive concept that circumvents the potential failure modes of a parachute terminal descent system. The design also possesses features that mitigate other risks during the entry, descent, landing and recovery phases. The results of a full-scale drop test are summarized.

  15. Aeroshell Design Techniques for Aerocapture Entry Vehicles

    NASA Technical Reports Server (NTRS)

    Dyke, R. Eric; Hrinda, Glenn A.

    2004-01-01

    A major goal of NASA s In-Space Propulsion Program is to shorten trip times for scientific planetary missions. To meet this challenge arrival speeds will increase, requiring significant braking for orbit insertion, and thus increased deceleration propellant mass that may exceed launch lift capabilities. A technology called aerocapture has been developed to expand the mission potential of exploratory probes destined for planets with suitable atmospheres. Aerocapture inserts a probe into planetary orbit via a single pass through the atmosphere using the probe s aeroshell drag to reduce velocity. The benefit of an aerocapture maneuver is a large reduction in propellant mass that may result in smaller, less costly missions and reduced mission cruise times. The methodology used to design rigid aerocapture aeroshells will be presented with an emphasis on a new systems tool under development. Current methods for fast, efficient evaluations of structural systems for exploratory vehicles to planets and moons within our solar system have been under development within NASA having limited success. Many systems tools that have been attempted applied structural mass estimation techniques based on historical data and curve fitting techniques that are difficult and cumbersome to apply to new vehicle concepts and missions. The resulting vehicle aeroshell mass may be incorrectly estimated or have high margins included to account for uncertainty. This new tool will reduce the guesswork previously found in conceptual aeroshell mass estimations.

  16. Flap effectiveness appraisal for winged re-entry vehicles

    NASA Astrophysics Data System (ADS)

    de Rosa, Donato; Pezzella, Giuseppe; Donelli, Raffaele S.; Viviani, Antonio

    2016-05-01

    The interactions between shock waves and boundary layer are commonplace in hypersonic aerodynamics. They represent a very challenging design issue for hypersonic vehicle. A typical example of shock wave boundary layer interaction is the flowfield past aerodynamic surfaces during control. As a consequence, such flow interaction phenomena influence both vehicle aerodynamics and aerothermodynamics. In this framework, the present research effort describes the numerical activity performed to simulate the flowfield past a deflected flap in hypersonic flowfield conditions for a winged re-entry vehicle.

  17. Parametric Thermal Soak Model for Earth Entry Vehicles

    NASA Technical Reports Server (NTRS)

    Agrawal, Parul; Samareh, Jamshid; Doan, Quy D.

    2013-01-01

    The analysis and design of an Earth Entry Vehicle (EEV) is multidisciplinary in nature, requiring the application many disciplines. An integrated tool called Multi Mission System Analysis for Planetary Entry Descent and Landing or M-SAPE is being developed as part of Entry Vehicle Technology project under In-Space Technology program. Integration of a multidisciplinary problem is a challenging task. Automation of the execution process and data transfer among disciplines can be accomplished to provide significant benefits. Thermal soak analysis and temperature predictions of various interior components of entry vehicle, including the impact foam and payload container are part of the solution that M-SAPE will offer to spacecraft designers. The present paper focuses on the thermal soak analysis of an entry vehicle design based on the Mars Sample Return entry vehicle geometry and discusses a technical approach to develop parametric models for thermal soak analysis that will be integrated into M-SAPE. One of the main objectives is to be able to identify the important parameters and to develop correlation coefficients so that, for a given trajectory, can estimate the peak payload temperature based on relevant trajectory parameters and vehicle geometry. The models are being developed for two primary thermal protection (TPS) materials: 1) carbon phenolic that was used for Galileo and Pioneer Venus probes and, 2) Phenolic Impregnated Carbon Ablator (PICA), TPS material for Mars Science Lab mission. Several representative trajectories were selected from a very large trade space to include in the thermal analysis in order to develop an effective parametric thermal soak model. The selected trajectories covered a wide range of heatload and heatflux combinations. Non-linear, fully transient, thermal finite element simulations were performed for the selected trajectories to generate the temperature histories at the interior of the vehicle. Figure 1 shows the finite element model

  18. Avionics architecture studies for the entry research vehicle

    NASA Technical Reports Server (NTRS)

    Dzwonczyk, M. J.; Mckinney, M. F.; Adams, S. J.; Gauthier, R. J.

    1989-01-01

    This report is the culmination of a year-long investigation of the avionics architecture for NASA's Entry Research Vehicle (ERV). The Entry Research Vehicle is conceived to be an unmanned, autonomous spacecraft to be deployed from the Shuttle. It will perform various aerodynamic and propulsive maneuvers in orbit and land at Edwards AFB after a 5 to 10 hour mission. The design and analysis of the vehicle's avionics architecture are detailed here. The architecture consists of a central triply redundant ultra-reliable fault tolerant processor attached to three replicated and distributed MIL-STD-1553 buses for input and output. The reliability analysis is detailed here. The architecture was found to be sufficiently reliable for the ERV mission plan.

  19. 48 CFR 945.570-2 - Acquisition of motor vehicles.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Acquisition of motor vehicles. (a) The GSA Interagency Fleet Management System (GSA-IFMS) is the first source... vehicles. 945.570-2 Section 945.570-2 Federal Acquisition Regulations System DEPARTMENT OF ENERGY CONTRACT... vehicles and light trucks. (g) The Office of Property Management, within the Headquarters...

  20. 48 CFR 945.570-2 - Acquisition of motor vehicles.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Acquisition of motor vehicles. (a) The GSA Interagency Fleet Management System (GSA-IFMS) is the first source... vehicles. 945.570-2 Section 945.570-2 Federal Acquisition Regulations System DEPARTMENT OF ENERGY CONTRACT... vehicles and light trucks. (g) The Office of Property Management, within the Headquarters...

  1. Test Results for Entry Guidance Methods for Space Vehicles

    NASA Technical Reports Server (NTRS)

    Hanson, John M.; Jones, Robert E.

    2004-01-01

    There are a number of approaches to advanced guidance and control that have the potential for achieving the goals of significantly increasing reusable launch vehicle (or any space vehicle that enters an atmosphere) safety and reliability, and reducing the cost. This paper examines some approaches to entry guidance. An effort called Integration and Testing of Advanced Guidance and Control Technologies has recently completed a rigorous testing phase where these algorithms faced high-fidelity vehicle models and were required to perform a variety of representative tests. The algorithm developers spent substantial effort improving the algorithm performance in the testing. This paper lists the test cases used to demonstrate that the desired results are achieved, shows an automated test scoring method that greatly reduces the evaluation effort required, and displays results of the tests. Results show a significant improvement over previous guidance approaches. The two best-scoring algorithm approaches show roughly equivalent results and are ready to be applied to future vehicle concepts.

  2. Inflatable Re-entry Vehicle Experiment (IRVE-4) Overview

    NASA Technical Reports Server (NTRS)

    Litton, Daniel K.; Bose, David M.; Cheatwood, F. McNeil; Hughes, Stephen; Wright, Henry S.; Lindell, Michael C.; Derry, Stephen D.; Olds, Aaron

    2011-01-01

    The suite of Inflatable Re-Entry Vehicle Experiments (IRVE) is designed to further our knowledge and understanding of Hypersonic Inflatable Aerodynamic Decelerators (HIADs). Before infusion into a future mission, three challenges need to be addressed: surviving the heat pulse during re-entry, demonstrating system performance at relevant scales, and demonstrating controllability in the atmosphere. IRVE-4 will contribute to a better understanding of controllability by characterizing how a HIAD responds to a set of controlled inputs. The ability to control a HIAD is vital for missions that are g-limited, require precision targeting and guidance for aerocapture or entry, descent, and landing. The IRVE-4 flight test will focus on taking a first look into controlling a HIAD. This paper will give an overview of the IRVE-4 mission including the control response portion of the flight test sequence, and will provide a review of the mission s development.

  3. Inflatable Re-Entry Vehicle Experiment (IRVE) Design Overview

    NASA Technical Reports Server (NTRS)

    Hughes, Stephen J.; Dillman, Robert A.; Starr, Brett R.; Stephan, Ryan A.; Lindell, Michael C.; Player, Charles J.; Cheatwood, F. McNeil

    2005-01-01

    Inflatable aeroshells offer several advantages over traditional rigid aeroshells for atmospheric entry. Inflatables offer increased payload volume fraction of the launch vehicle shroud and the possibility to deliver more payload mass to the surface for equivalent trajectory constraints. An inflatable s diameter is not constrained by the launch vehicle shroud. The resultant larger drag area can provide deceleration equivalent to a rigid system at higher atmospheric altitudes, thus offering access to higher landing sites. When stowed for launch and cruise, inflatable aeroshells allow access to the payload after the vehicle is integrated for launch and offer direct access to vehicle structure for structural attachment with the launch vehicle. They also offer an opportunity to eliminate system duplication between the cruise stage and entry vehicle. There are however several potential technical challenges for inflatable aeroshells. First and foremost is the fact that they are flexible structures. That flexibility could lead to unpredictable drag performance or an aerostructural dynamic instability. In addition, durability of large inflatable structures may limit their application. They are susceptible to puncture, a potentially catastrophic insult, from many possible sources. Finally, aerothermal heating during planetary entry poses a significant challenge to a thin membrane. NASA Langley Research Center and NASA's Wallops Flight Facility are jointly developing inflatable aeroshell technology for use on future NASA missions. The technology will be demonstrated in the Inflatable Re-entry Vehicle Experiment (IRVE). This paper will detail the development of the initial IRVE inflatable system to be launched on a Terrier/Orion sounding rocket in the fourth quarter of CY2005. The experiment will demonstrate achievable packaging efficiency of the inflatable aeroshell for launch, inflation, leak performance of the inflatable system throughout the flight regime, structural

  4. Investigations of Control Surface Seals for Re-entry Vehicles

    NASA Technical Reports Server (NTRS)

    Dunlap, Patrick H., Jr.; Steinetz, Bruce M.; Curry, Donald M.; DeMange, Jeffrey J.; Rivers, H. Kevin; Hsu, Su-Yuen

    2002-01-01

    Re-entry vehicles generally require control surfaces (e.g., rudders, body flaps) to steer them during flight. Control surface seals are installed along hinge lines and where control surface edges move close to the vehicle body. These seals must operate at high temperatures and limit heat transfer to underlying structures to prevent them from overheating and causing possible loss of vehicle structural integrity. This paper presents results for thermal analyses and mechanical testing conducted on the baseline rudder/fin seal design for the X-38 re-entry vehicle. Exposure of the seals in a compressed state at the predicted peak seal temperature of 1900 F resulted in loss of seal resiliency. The vertical Inconel rudder/fin rub surface was re-designed to account for this loss of resiliency. Room temperature compression tests revealed that seal unit loads and contact pressures were below limits set to protect Shuttle thermal tiles on the horizontal sealing surface. The seals survived an ambient temperature 1000 cycle scrub test over sanded Shuttle tiles and were able to disengage and re-engage the tile edges during testing. Arc jet tests confirmed the need for seals in the rudder/fin gap location because a single seal caused a large temperature drop (delta T = 1710 F) in the gap.

  5. Investigations of Control Surface Seals for Re-Entry Vehicles

    NASA Astrophysics Data System (ADS)

    Dunlap, Patrick H., Jr.; Steinetz, Bruce M.; Curry, Donald M.; DeMange, Jeffrey J.; Rivers, H. Kevin; Hsu, Su-Yuen

    2002-07-01

    Re-entry vehicles generally require control surfaces (e.g., rudders, body flaps) to steer them during flight. Control surface seals are installed along hinge lines and where control surface edges move close to the vehicle body. These seals must operate at high temperatures and limit heat transfer to underlying structures to prevent them from overheating and causing possible loss of vehicle structural integrity. This paper presents results for thermal analyses and mechanical testing conducted on the baseline rudder/fin seal design for the X-38 re-entry vehicle. Exposure of the seals in a compressed state at the predicted peak seal temperature of 1900 F resulted in loss of seal resiliency. The vertical Inconel rudder/fin rub surface was re-designed to account for this loss of resiliency. Room temperature compression tests revealed that seal unit loads and contact pressures were below limits set to protect Shuttle thermal tiles on the horizontal sealing surface. The seals survived an ambient temperature 1000 cycle scrub test over sanded Shuttle tiles and were able to disengage and re-engage the tile edges during testing. Arc jet tests confirmed the need for seals in the rudder/fin gap location because a single seal caused a large temperature drop (delta T = 1710 F) in the gap.

  6. Test Results for Entry Guidance Methods for Reusable Launch Vehicles

    NASA Technical Reports Server (NTRS)

    Hanson, John M.; Jones, Robert E.

    2003-01-01

    There are a number of approaches to advanced guidance and control (AG&C) that have the potential for achieving the goals of significantly increasing reusable launch vehicle (RLV) safety and reliability, and reducing the cost. This paper examines some approaches to entry guidance. An effort called Integration and Testing of Advanced Guidance and Control Technologies (ITAGCT) has recently completed a rigorous testing phase where these algorithms faced high-fidelity vehicle models and were required to perform a variety of representative tests. The algorithm developers spent substantial effort improving the algorithm performance in the testing. This paper lists the test cases used to demonstrate that the desired results are achieved, shows an automated test scoring method that greatly reduces the evaluation effort required, and displays results of the tests. Results show a significant improvement over previous guidance approaches. The two best-scoring algorithm approaches show roughly equivalent results and are ready to be applied to future reusable vehicle concepts.

  7. Grid generation and flow computation about a Martian entry vehicle

    NASA Technical Reports Server (NTRS)

    Stewart, J. E.; Tiwari, S. N.

    1990-01-01

    A number of vehicles are currently being proposed for a manned mission to Mars. One of these vehicles has a modified blunt-nosed cone configuration. Experimental results were obtained for this vehicle in 1968. They show lift-over-drag ratios comparable to those needed for Mars entry. Computations are performed to verify the earlier results and to further describe the flight characteristics of this vehicle. An analytical method is used to define the surface of this vehicle. A single-block volume grid is generated around the vehicle using the algebraic Two-Boundary Grid Generation algorithm (TBGG) and transfinite interpolation. Euler solutions are then obtained from a Langley Aerodynamic Upward Relaxation Algorithm (LAURA) at Mach 6.0 and angles of attack of 0, 6, and 12 deg. The lift coefficient determined from the LAURA code agree very well with the experimental results. The drag and pitching moment coefficients, however, are underestimated by the code since viscous effects are not considered. Contour plots of the flowfield show no evidence of separation for angles of attack up to 12 deg.

  8. High performance modeling of atmospheric re-entry vehicles

    NASA Astrophysics Data System (ADS)

    Martin, Alexandre; Scalabrin, Leonardo C.; Boyd, Iain D.

    2012-02-01

    Re-entry vehicles designed for space exploration are usually equipped with thermal protection systems made of ablative material. In order to properly model and predict the aerothermal environment of the vehicle, it is imperative to account for the gases produced by ablation processes. In the case of charring ablators, where an inner resin is pyrolyzed at a relatively low temperature, the composition of the gas expelled into the boundary layer is complex and may lead to thermal chemical reactions that cannot be captured with simple flow chemistry models. In order to obtain better predictions, an appropriate gas flow chemistry model needs to be included in the CFD calculations. Using a recently developed chemistry model for ablating carbon-phenolic-in-air species, a CFD calculation of the Stardust re-entry at 71 km is presented. The code used for that purpose has been designed to take advantage of the nature of the problem and therefore remains very efficient when a high number of chemical species are involved. The CFD result demonstrates the need for such chemistry model when modeling the flow field around an ablative material. Modeling of the nonequilibrium radiation spectra is also presented, and compared to the experimental data obtained during Stardust re-entry by the Echelle instrument. The predicted emission from the CN lines compares quite well with the experimental results, demonstrating the validity of the current approach.

  9. Predictor-Corrector Entry Guidance for Reusable Launch Vehicles

    NASA Technical Reports Server (NTRS)

    Youssef, Hussein; Chowdhry, Rajiv; Lee, Howard; Zimmerman, Curtis; Brandon, Larry (Technical Monitor)

    2001-01-01

    An online entry guidance algorithm has been developed using a predictor-corrector approach. The algorithm is designed for the Reusable Launch Vehicle (RLV) and is demonstrated by using, the X-33 model. The objective of the design is to handle widely dispersed entry conditions and deliver the vehicle at the Terminal Area Energy Management (TAEM) interface box within an acceptable tolerance and without violating any of the vehicle physical constraints. Combination of several control variables is used in testing the performance and computational requirement of the algorithm. The control variables are the bank angle, angle-of-attack and the time for roll reversal. The bank angle and angle-of-attack profiles are the nominal profiles plus the perturbations in each direction. The initial guess of the bank profile is a 45 degrees bank angle with reversal at 360 seconds from liftoff. A six-element state vector is propagated to the TAEM interface box through the integration of the equations of motion (EOM). Altitude, heading and range errors are computed between the desired and the achieved state at the TAEM interface. These errors are used to correct the initial guess of the control variables. This process is repeated until the errors meet an acceptable level at the TAEM interface. Several numerical optimization methods are used to evaluate the convergent property of the predictor-predictor methodology. Successful results are demonstrated using the X-33 model.

  10. Potential for Integrating Entry Guidance into the Multi-Disciplinary Entry Vehicle Optimization Environment

    NASA Technical Reports Server (NTRS)

    D'souza, Sarah N.; Kinney, David J.; Garcia, Joseph A.; Sarigul-Klijn, Nesrin

    2014-01-01

    The state-of-the-art in vehicle design decouples flight feasible trajectory generation from the optimization process of an entry spacecraft shape. The disadvantage to this decoupled process is seen when a particular aeroshell does not meet in-flight requirements when integrated into Guidance, Navigation, and Control simulations. It is postulated that the integration of a guidance algorithm into the design process will provide a real-time, rapid trajectory generation technique to enhance the robustness of vehicle design solutions. The potential benefit of this integration is a reduction in design cycles (possible cost savings) and increased accuracy in the aerothermal environment (possible mass savings). This work examines two aspects: 1) the performance of a reference tracking guidance algorithm for five different geometries with the same reference trajectory and 2) the potential of mass savings from improved aerothermal predictions. An Apollo Derived Guidance (ADG) algorithm is used in this study. The baseline geometry and five test case geometries were flown using the same baseline trajectory. The guided trajectory results are compared to separate trajectories determined in a vehicle optimization study conducted for NASA's Mars Entry, Descent, and Landing System Analysis. This study revealed several aspects regarding the potential gains and required developments for integrating a guidance algorithm into the vehicle optimization environment. First, the generation of flight feasible trajectories is only as good as the robustness of the guidance algorithm. The set of dispersed geometries modelled aerodynamic dispersions that ranged from +/-1% to +/-17% and a single extreme case was modelled where the aerodynamics were approximately 80% less than the baseline geometry. The ADG, as expected, was able to guide the vehicle into the aeroshell separation box at the target location for dispersions up to 17%, but failed for the 80% dispersion cases. Finally, the results

  11. 48 CFR 945.570-2 - Acquisition of motor vehicles.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... agencies. All requisitions (GSA Form 1781) shall be processed in accordance with 41 CFR 101-26.501. (d... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Acquisition of motor... Acquisition of motor vehicles. (a) The GSA Interagency Fleet Management System (GSA-IFMS) is the first...

  12. 48 CFR 945.570-1 - Acquisition of motor vehicles.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... vehicles. (a) GSA Interagency Fleet Management System (GSA-IFMS) is the first source of supply for... vehicles. 945.570-1 Section 945.570-1 Federal Acquisition Regulations System DEPARTMENT OF ENERGY CONTRACT... in accordance with 41 CFR 101-26.501. (d) Contractors shall submit all motor vehicle requirements...

  13. 48 CFR 945.570-1 - Acquisition of motor vehicles.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... vehicles. (a) GSA Interagency Fleet Management System (GSA-IFMS) is the first source of supply for... vehicles. 945.570-1 Section 945.570-1 Federal Acquisition Regulations System DEPARTMENT OF ENERGY CONTRACT... in accordance with 41 CFR 101-26.501. (d) Contractors shall submit all motor vehicle requirements...

  14. Afterbody Heating Predictions for a Mars Science Laboratory Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Edquist, Karl T.

    2005-01-01

    The Mars Science Laboratory mission intends to deliver a large rover to the Martian surface within 10 km of its target site. One candidate entry vehicle aeroshell consists of a 3.75-m diameter, 70-deg sphere-cone forebody and a biconic afterbody similar to that of Viking. This paper presents computational fluid dynamics predictions of laminar afterbody heating rates for this configuration and a 2010 arrival at Mars. Computational solutions at flight conditions used an 8-species Mars gas model in chemical and thermal non-equilibrium. A grid resolution study examined the effects of mesh spacing on afterbody heating rates and resulted in grids used for heating predictions on a reference entry trajectory. Afterbody heating rate reaches its maximum value near 0.6 W/sq cm on the first windward afterbody cone at the time of peak freestream dynamic pressure. Predicted afterbody heating rates generally are below 3% of the forebody laminar nose cap heating rate throughout the design trajectory. The heating rates integrated over time provide total heat load during entry, which drives thermal protection material thickness.

  15. Integrated Composite Stiffener Structure (ICoSS) Concept for Planetary Entry Vehicles

    NASA Technical Reports Server (NTRS)

    Kellas, Sotiris

    2016-01-01

    Results from the design, manufacturing, and testing of a lightweight Integrated Composite Stiffened Structure (ICoSS) concept, intended for multi-mission planetary entry vehicles are presented. Tests from both component and full-scale tests for a typical Earth Entry Vehicle forward shell manufactured using the ICoSS concept are presented and advantages of the concept for the particular application of passive Earth Entry Vehicles over other structural concepts are discussed.

  16. NOVA-NREL Optimal Vehicle Acquisition Analysis (Brochure)

    SciTech Connect

    Blakley, H.

    2011-03-01

    Federal fleet managers face unique challenges in accomplishing their mission - meeting agency transportation needs while complying with Federal goals and mandates. Included in these challenges are a variety of statutory requirements, executive orders, and internal goals and objectives that typically focus on petroleum consumption and greenhouse gas (GHG) emissions reductions, alternative fuel vehicle (AFV) acquisitions, and alternative fuel use increases. Given the large number of mandates affecting Federal fleets and the challenges faced by all fleet managers in executing day-to-day operations, a primary challenge for agencies and other organizations is ensuring that they are as efficient as possible in using constrained fleet budgets. An NREL Optimal Vehicle Acquisition (NOVA) analysis makes use of a mathematical model with a variety of fleet-related data to create an optimal vehicle acquisition strategy for a given goal, such as petroleum or GHG reduction. The analysis can helps fleets develop a vehicle acquisition strategy that maximizes petroleum and greenhouse gas reductions.

  17. Discussion of flight experiments with an entry research vehicle

    NASA Technical Reports Server (NTRS)

    Potter, J. L.

    1985-01-01

    The focus of interest is the maneuvering flight of advanced entry vehicles operating at altitudes above 50 km and at velocities of 5 to 8 km/s. Information resulting in more accurate aerodynamic analysis is sought and measurement techniques that appear to be applicable are identified. Measurements discussed include: shock layer or boundary layer profiles of velocity, temperature, species mass fractions, and other gas properties associated with aerodynamic heating; surface energy transfer process; nonequilibrium flow processes and pressure distribution; separated, vortic leeside flow of nonequilibrium fluid; boundary layer transition on highly swept configurations; and shock and surface slip and gas/surface interaction. Further study should focus on evolving measurement techniques, installation requirements, and on identification of the portions of flights where successful results seem probable.

  18. Passivity analysis for a winged re-entry vehicle

    NASA Astrophysics Data System (ADS)

    Mooij, E.

    2014-12-01

    Application of simple adaptive control (SAC) theory to the design of guidance and control systems for winged re-entry vehicles has been proven successful. To apply SAC to these non-linear and non-stationary systems, it needs to be Almost Strictly Passive (ASP), which is an extension of the Almost Strictly Positive Real (ASPR) condition for linear, time-invariant systems. To fulfill the ASP condition, the controlled, non-linear system has to be minimum-phase (i.e., the zero dynamics is stable), and there is a specific condition for the product of output and input matrix. Earlier studies indicate that even the linearised system is not ASPR. The two problems at hand are: 1) the system is non-minimum phase when flying with zero bank angle, and 2) whenever there is hybrid control, e.g., yaw control is established by combined reaction and aerodynamic control for the major part of flight, the second ASPR condition cannot be met. In this paper we look at both issues, the former related to the guidance system and the latter to the attitude-control system. It is concluded that whenever the nominal bank angle is zero, the passivity conditions can never be met, and guidance should be based on nominal commands and a redefinition of those whenever the error becomes too large. For the remaining part of the trajectory, the passivity conditions are marginally met, but it is proposed to add feedforward compensators to alleviate these conditions. The issue of hybrid control is avoided by redefining the controls with total control moments and adding a so-called control allocator. Deriving the passivity conditions for rotational motion, and evaluating these conditions along the trajectory shows that the (non-linear) winged entry vehicle is ASP. The sufficient conditions to apply SAC for attitude control are thus met.

  19. Passivity analysis for a winged re-entry vehicle

    SciTech Connect

    Mooij, E.

    2014-12-10

    Application of simple adaptive control (SAC) theory to the design of guidance and control systems for winged re-entry vehicles has been proven successful. To apply SAC to these non-linear and non-stationary systems, it needs to be Almost Strictly Passive (ASP), which is an extension of the Almost Strictly Positive Real (ASPR) condition for linear, time-invariant systems. To fulfill the ASP condition, the controlled, non-linear system has to be minimum-phase (i.e., the zero dynamics is stable), and there is a specific condition for the product of output and input matrix. Earlier studies indicate that even the linearised system is not ASPR. The two problems at hand are: 1) the system is non-minimum phase when flying with zero bank angle, and 2) whenever there is hybrid control, e.g., yaw control is established by combined reaction and aerodynamic control for the major part of flight, the second ASPR condition cannot be met. In this paper we look at both issues, the former related to the guidance system and the latter to the attitude-control system. It is concluded that whenever the nominal bank angle is zero, the passivity conditions can never be met, and guidance should be based on nominal commands and a redefinition of those whenever the error becomes too large. For the remaining part of the trajectory, the passivity conditions are marginally met, but it is proposed to add feedforward compensators to alleviate these conditions. The issue of hybrid control is avoided by redefining the controls with total control moments and adding a so-called control allocator. Deriving the passivity conditions for rotational motion, and evaluating these conditions along the trajectory shows that the (non-linear) winged entry vehicle is ASP. The sufficient conditions to apply SAC for attitude control are thus met.

  20. Experimental and Computational Aerothermodynamics of a Mars Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Hollis, Brian R.

    1996-01-01

    An aerothermodynamic database has been generated through both experimental testing and computational fluid dynamics simulations for a 70 deg sphere-cone configuration based on the NASA Mars Pathfinder entry vehicle. The aerothermodynamics of several related parametric configurations were also investigated. Experimental heat-transfer data were obtained at hypersonic test conditions in both a perfect gas air wind tunnel and in a hypervelocity, high-enthalpy expansion tube in which both air and carbon dioxide were employed as test gases. In these facilities, measurements were made with thin-film temperature-resistance gages on both the entry vehicle models and on the support stings of the models. Computational results for freestream conditions equivalent to those of the test facilities were generated using an axisymmetric/2D laminar Navier-Stokes solver with both perfect-gas and nonequilibrium thermochemical models. Forebody computational and experimental heating distributions agreed to within the experimental uncertainty for both the perfect-gas and high-enthalpy test conditions. In the wake, quantitative differences between experimental and computational heating distributions for the perfect-gas conditions indicated transition of the free shear layer near the reattachment point on the sting. For the high enthalpy cases, agreement to within, or slightly greater than, the experimental uncertainty was achieved in the wake except within the recirculation region, where further grid resolution appeared to be required. Comparisons between the perfect-gas and high-enthalpy results indicated that the wake remained laminar at the high-enthalpy test conditions, for which the Reynolds number was significantly lower than that of the perfect-gas conditions.

  1. Transition Analysis for the Mars Science Laboratory Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Chang, Chau-Lyan; Choudhari, Meelan M.; Hollis, Brian R.; Li, Fei

    2009-01-01

    Viscous Laminar-turbulent transition plays an important role in the design of the Mars Science Laboratory (MSL) entry vehicle. The lift-to-drag ratio required for the precision landing trajectory will be achieved via an angle of attack equal to 16 degrees. At this relatively high angle of attack, the boundary layer flow near the leeward meridian is expected to transition early in the trajectory, resulting in substantially increased heating loads. This paper presents stability calculations and transition correlations for a series of wind tunnel models of the MSL vehicle. Experimentally measured transition onset locations are used to correlate with the N-factor calculations for various wind tunnel conditions. Due to relatively low post-shock Mach numbers near the edge of the boundary layer, the dominant instability waves are found to be of the first mode type. The N-factor values correlating with measured transition onset at selected test points from the Mach 6 conventional facility experiments fall between 3.5 and 4.5 and apparently vary linearly with the wind tunnel unit Reynolds number, indicating strong receptivity effect. The small transition N value is consistent with previous correlations for second-mode dominant transition in the same wind tunnel facility. Stability calculations for stationary and traveling crossflow instability waves in selected configurations indicate that an N value of 4 and 6, respectively, correlates reasonably well with transition onset discerned from one experimentally measured thermographic image.

  2. Turbulent Aeroheating Testing of Mars Science Laboratory Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Hollis, Brian R.; Collier, Arnold S.

    2008-01-01

    An experimental investigation of turbulent aeroheating on the Mars Science Laboratory entry vehicle heat shield has been conducted in the Arnold Engineering Development Center Hypervelocity Wind Tunnel No. 9. Testing was performed on a 6-in. (0.1524 m) diameter MSL model in pure N2 gas in the tunnel's Mach 8 and Mach 10 nozzles at free stream Reynolds numbers of 4.1 x 10(exp 6)/ft to 49 x 10(exp 6)/ft (1.3 x 10(exp 7)/m to 19 x 10(exp 6/ft) and 1.2 x 10(exp 6)/ft to 19 x 10(exp 6)/ft (0.39 x 10(exp 7)/m to 62 x 10(exp 7)/m), respectively. These conditions were sufficient to span the regime of boundary-layer flow from completely laminar to fully-developed turbulent flow over the entire forebody. A supporting aeroheating test was also conducted in the Langley Research Center 20-Inch Mach 6 Air Tunnel at free stream Reynolds number of 1 x 10(exp 6)/ft to 7 x 10(exp 6)/ft (0.36 x 10(exp 7)/m to 2.2 x 10(exp 7)/m) in order to help corroborate the Tunnel 9 results. A complementary computational fluid dynamics study was conducted in parallel to the wind tunnel testing. Laminar and turbulent predictions were generated for the wind tunnel test conditions and comparisons were performed with the data for the purpose of helping to define uncertainty margins on predictions for aeroheating environments during entry into the Martian atmosphere. Data from both wind tunnel tests and comparisons with the predictions are presented herein. It was concluded from these comparisons that for perfect-gas conditions, the computational tools could predict fully-laminar or fully-turbulent heating conditions to within 12% or better of the experimental data.

  3. Venus Atmospheric Maneuverable Platform (VAMP) — Air Vehicle Concept and Entry CONOPs

    NASA Astrophysics Data System (ADS)

    Sokol, D.; Lee, G.; Polidan, R.; Bolisay, L.; Barnes, N.

    2014-06-01

    This presentation discusses the continued development of the Northrop Grumman/L’GARDE team’s long-lived, maneuverable platform to explore the Venus upper atmosphere. It focuses on the air vehicle design and entry CONOPs and their interdependencies.

  4. Aeroheating Test of CEV Entry Vehicle at Turbulent Conditions

    NASA Technical Reports Server (NTRS)

    Hollis, Brian R.; Berger, Karen T.; Horvath, Thomas J.; Coblish, Joseph J.; Norris, Joseph D.; Lillard, Randolph P.; Kirk, Ben

    2008-01-01

    An investigation of the aeroheating environment of the Project Orion Crew Entry Vehicle has been performed in the Arnold Engineering Development Center Tunnel 9. Data were measured on a approx. 3.5% scale model (0.1778m/7-inch diam.) of the vehicle using coaxial thermocouples in the Mach 8 and Mach 10 nozzles of Tunnel 9. Runs were performed at free stream Reynolds numbers of 1 106/ft to 20 10(exp 6)/ft in the Mach 10 nozzle and 8 10(exp 6)/ft to 48 10(exp 6)/ft in the Mach 8 nozzle. The test gas in Tunnel 9 is pure N2, which at these operating conditions remains un-dissociated and may be treated as a perfect gas. At these conditions, laminar, transitional, and turbulent flow was produced on the model at Mach 10, and transitional and turbulent conditions were produced on the model at Mach 8. The majority of runs were made on a clean, smooth-surface model configuration and a limited number of runs were made in which inserts with varying boundary-layer trips configurations were used to force the occurrence of transition. Laminar and turbulent predictions were generated for all wind tunnel test conditions and comparisons were performed with the data for the purpose of helping to define uncertainty margins for the computational method. Data from both the wind tunnel test and the computations are presented herein. Figure 1 shows a schematic of the thermocouple locations on the model and figures 2 and 3 show a photo and schematic of the AEDC Hypervelocity Tunnel 9. Figure 4 shows a typical grid used in the computations. From the comparisons shown in figures 5 through 8 it was concluded that for perfect-gas conditions, the computations could predict either fully-laminar or full-turbulent flow to within +/-10% of the experimental data. The experimental data showed that transition began on the leeside of the heatshield at a free stream Reynolds number of 9 10(exp 6)/ft in the Mach 10 nozzle and fully-developed turbulent flow was produced at 20 10(exp 6)/ft. In the Mach 8

  5. Preliminary Thermal Analysis of a Mars Sample Return Earth Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Amundsen, Ruth M.; Dec, John A.; Mitcheltree, Robert A.; Lindell, Michael C.; Dillman, Robert A.

    2000-01-01

    Thermal analysis of a vehicle designed to return samples from another planet, such as the Earth Entry vehicle for the Mars Sample Return mission, presents several unique challenges. The scientific purpose of a sample return mission is to return samples to Earth for detailed investigation. The Earth Entry Vehicle (EEV) must contain the samples after they have been collected and protect them from the high hearing rates of entry into the Earth's atmosphere. This requirement necessitates inclusion of detailed thermal analysis early in the design of the vehicle. This paper will describe the challenges and solutions for a preliminary thermal analysis of an Earth Entry Vehicle. The primary challenges included accurate updates of model .geometry, applying heat fluxes that change with position and time during exo-atmospheric cruise and entry, and incorporating orthotropic material properties. Many different scenarios were evaluated for the exo-atmospheric cruise to attain the desired thermal condition. The severity of the heat pulse during entry and the material response led to some unique modeling solutions. Overall, advanced modeling techniques and mathematical solutions were successfully used in predicting the thermal behavior of this complex system.

  6. Simulation-Based Analysis of Reentry Dynamics for the Sharp Atmospheric Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Tillier, Clemens Emmanuel

    1998-01-01

    This thesis describes the analysis of the reentry dynamics of a high-performance lifting atmospheric entry vehicle through numerical simulation tools. The vehicle, named SHARP, is currently being developed by the Thermal Protection Materials and Systems branch of NASA Ames Research Center, Moffett Field, California. The goal of this project is to provide insight into trajectory tradeoffs and vehicle dynamics using simulation tools that are powerful, flexible, user-friendly and inexpensive. Implemented Using MATLAB and SIMULINK, these tools are developed with an eye towards further use in the conceptual design of the SHARP vehicle's trajectory and flight control systems. A trajectory simulator is used to quantify the entry capabilities of the vehicle subject to various operational constraints. Using an aerodynamic database computed by NASA and a model of the earth, the simulator generates the vehicle trajectory in three-dimensional space based on aerodynamic angle inputs. Requirements for entry along the SHARP aerothermal performance constraint are evaluated for different control strategies. Effect of vehicle mass on entry parameters is investigated, and the cross range capability of the vehicle is evaluated. Trajectory results are presented and interpreted. A six degree of freedom simulator builds on the trajectory simulator and provides attitude simulation for future entry controls development. A Newtonian aerodynamic model including control surfaces and a mass model are developed. A visualization tool for interpreting simulation results is described. Control surfaces are roughly sized. A simple controller is developed to fly the vehicle along its aerothermal performance constraint using aerodynamic flaps for control. This end-to-end demonstration proves the suitability of the 6-DOF simulator for future flight control system development. Finally, issues surrounding real-time simulation with hardware in the loop are discussed.

  7. The Advanced Re-Entry Vehicle (ARV) A Development Step From ATV Toward Manned Transportation Systems

    NASA Astrophysics Data System (ADS)

    Bottacini, Massimiliano; Berthe, Philippe; Vo, Xavier; Pietsch, Klaus

    2011-05-01

    The Advanced Re-entry Vehicle (ARV) programme has been undertaken by Europe with the objective to contribute to the preparation of a future European crew transportation system, while providing a valuable logistic support to the ISS through an operational cargo return system. This development would allow: - the early acquisition of critical technologies; - the design, development and testing of elements suitable for the follow up human rated transportation system. These vehicles should also serve future LEO infrastructures and exploration missions. With the aim to satisfy the above objectives a team composed by major European industries and led by EADS Astrium Space Transportation is currently conducting the phase A of the programme under contract with the European Space Agency (ESA). Two vehicle versions are being investigated: a Cargo version, transporting cargo only to/from the ISS, and a Crew version, which will allow the transfer of both crew and cargo to/from the ISS. The ARV Cargo version, in its present configuration, is composed of three modules. The Versatile Service Module (VSM) provides to the system the propulsion/GNC for orbital manoeuvres and attitude control and the orbital power generation. Its propulsion system and GNC shall be robust enough to allow its use for different launch stacks and different LEO missions in the future. The Un-pressurised Cargo Module (UCM) provides the accommodation for about 3000 kg of unpressurised cargo and is to be sufficiently flexible to ensure the transportation of: - orbital infrastructure components (ORU’s); - scientific / technological experiments; - propellant for re-fuelling, re-boost (and de-orbiting) of the ISS. The Re-entry Module (RM) provides a pressurized volume to accommodate active/passive cargo (2000 kg upload/1500 kg download). It is conceived as an expendable conical capsule with spherical heat-shield, interfacing with the new docking standard of the ISS, i.e. it carries the IBDM docking system, on

  8. The Advanced Re-Entry Vehicle (ARV) a Development Step from ATV Toward Manned Transportation Systems

    NASA Astrophysics Data System (ADS)

    Bottacini, M.; Berthe, P.; Vo, X.; Pietsch, K.

    2011-08-01

    The Advanced Re-entry Vehicle (ARV) programme has been undertaken by Europe with the objective to contribute to the preparation of a future European crew transportation system, while providing a valuable logistic support to the ISS through an operational cargo return system. This development would allow: - the early acquisition of critical technologies; - the design, development and testing of elements suitable for the follow up human rated transportation system. These vehicles should also serve future LEO infrastructures and exploration missions. With the aim to satisfy the above objectives a team composed by major European industries and led by EADS Astrium Space Transportation is currently conducting the phase A of the programme under contract with the European Space Agency (ESA). Two vehicle versions are being investigated: a Cargo version, transporting cargo only to/from the ISS, and a Crew version, which will allow the transfer of both crew and cargo to/from the ISS. The ARV Cargo version, in its present configuration, is composed of three modules. The Versatile Service Module (VSM) provides to the system the propulsion/GNC for orbital manoeuvres and attitude control and the orbital power generation. Its propulsion system and GNC shall be robust enough to allow its use for different launch stacks and different LEO missions in the future. The Un-pressurised Cargo Module (UCM) provides the accommodation for about 3000 kg of un-pressurised cargo and is to be sufficiently flexible to ensure the transportation of: - orbital infrastructure components (ORU's); - scientific / technological experiments; - propellant for re-fuelling, re-boost (and deorbiting) of the ISS. The Re-entry Module (RM) provides a pressurized volume to accommodate active/passive cargo (2000 kg upload/1500 kg download). It is conceived as an expendable conical capsule with spherical heat- hield, interfacing with the new docking standard of the ISS, i.e. it carries the IBDM docking system, on a

  9. Multi-Mission Earth Entry Vehicle: Aerodynamic and Aerothermal Analysis of Trajectory Environments

    NASA Technical Reports Server (NTRS)

    Trumble, Kerry; Dyakonov, Artem; Fuller, John

    2010-01-01

    Multi-mission Earth Entry Vehicle (MMEEV) is designed to deliver small payloads from space to Earth's surface by flying an uncontrolled ballistic entry, which ends with ground impact. The included range of entry velocities is from 10 to 16 km/s. The range of ballistic coefficients is from 41.94 to 128.74 kg/m2, which insures a low subsonic terminal velocity on the order of 50 m/sec. The range of entry flight path angles, considered in this analysis is from -5 to -25 degrees. The assessment and parametric characterization of aeroheating and aerodynamic performance of the capsule during entry is the subject of this paper.

  10. Hypersonic and Supersonic Static Aerodynamics of Mars Science Laboratory Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Dyakonov, Artem A.; Schoenenberger, Mark; Vannorman, John W.

    2012-01-01

    This paper describes the analysis of continuum static aerodynamics of Mars Science Laboratory (MSL) entry vehicle (EV). The method is derived from earlier work for Mars Exploration Rover (MER) and Mars Path Finder (MPF) and the appropriate additions are made in the areas where physics are different from what the prior entry systems would encounter. These additions include the considerations for the high angle of attack of MSL EV, ablation of the heatshield during entry, turbulent boundary layer, and other aspects relevant to the flight performance of MSL. Details of the work, the supporting data and conclusions of the investigation are presented.

  11. Minimum Heating Re-Entry Trajectories for Advanced Hypersonic Launch Vehicles

    NASA Technical Reports Server (NTRS)

    Windhorst, Robert

    1997-01-01

    Optimal re-entry trajectories are generated for reusable launch vehicles which minimize: (1) the heat absorbed at the vehicle surface, (2) the lower surface temperature, and (3) the heat absorbed by the internal structure. The approach uses the energy state approximation technique and a finite control volume heat transfer code coupled to a flight path integration code. These trajectories are compared to the optimal re-entry trajectory minimizing the integrated convective heat rate to determine which trajectory produces the minimum internal structural temperatures for a given thermal protection system. Three different thermal protection systems are considered: tile, blanket, and metallic.

  12. Planetary Mission Entry Vehicles Quick Reference Guide. Version 3.0

    NASA Technical Reports Server (NTRS)

    Davies, Carol; Arcadi, Marla

    2006-01-01

    This is Version 3.0 of the planetary mission entry vehicle document. Three new missions, Re-entry F, Hayabusa, and ARD have been added to t he previously published edition (Version 2.1). In addition, the Huyge ns mission has been significantly updated and some Apollo data correc ted. Due to the changing nature of planetary vehicles during the desi gn, manufacture and mission phases, and to the variables involved in measurement and computation, please be aware that the data provided h erein cannot be guaranteed. Contact Carol Davies at cdavies@mail.arc. nasa.gov to correct or update the current data, or to suggest other missions.

  13. Optimizing Federal Fleet Vehicle Acquisitions: An Eleven-Agency FY 2012 Analysis

    SciTech Connect

    Singer, M.; Daley, R.

    2015-02-01

    This report focuses on the National Renewable Energy Laboratory's (NREL) fiscal year (FY) 2012 effort that used the NREL Optimal Vehicle Acquisition (NOVA) analysis to identify optimal vehicle acquisition recommendations for eleven diverse federal agencies. Results of the study show that by following a vehicle acquisition plan that maximizes the reduction in greenhouse gas (GHG) emissions, significant progress is also made toward the mandated complementary goals of acquiring alternative fuel vehicles, petroleum use reduction, and alternative fuel use increase.

  14. Trajectory optimization study of a lifting body re-entry vehicle for medium to intermediate range applications

    NASA Astrophysics Data System (ADS)

    Rizvi, S. Tauqeer ul Islam; Linshu, He; ur Rehman, Tawfiq; Rafique, Amer Farhan

    2012-11-01

    A numerical optimization study of lifting body re-entry vehicles is presented for nominal as well as shallow entry conditions for Medium and Intermediate Range applications. Due to the stringent requirement of a high degree of accuracy for conventional vehicles, lifting re-entry can be used to attain the impact at the desired terminal flight path angle and speed and thus can potentially improve accuracy of the re-entry vehicle. The re-entry of a medium range and intermediate range vehicles is characterized by very high negative flight path angle and low re-entry speed as compared to a maneuverable re-entry vehicle or a common aero vehicle intended for an intercontinental range. Highly negative flight path angles at the re-entry impose high dynamic pressure as well as heat loads on the vehicle. The trajectory studies are carried out to maximize the cross range of the re-entry vehicle while imposing a maximum dynamic pressure constraint of 350 KPa with a 3 MW/m2 heat rate limit. The maximum normal acceleration and the total heat load experienced by the vehicle at the stagnation point during the maneuver have been computed for the vehicle for possible future conceptual design studies. It has been found that cross range capability of up to 35 km can be achieved with a lifting-body design within the heat rate and the dynamic pressure boundary at normal entry conditions. For shallow entry angle of -20 degree and intermediate ranges a cross range capability of up to 250 km can be attained for a lifting body design with less than 10 percent loss in overall range. The normal acceleration also remains within limits. The lifting-body results have also been compared with wing-body results at shallow entry condition. An hp-adaptive pseudo-spectral method has been used for constrained trajectory optimization.

  15. 48 CFR 908.7101-2 - Consolidated acquisition of new vehicles by General Services Administration.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Consolidated acquisition of new vehicles by General Services Administration. 908.7101-2 Section 908.7101-2 Federal Acquisition Regulations System DEPARTMENT OF ENERGY COMPETITION ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Acquisition of Special...

  16. 48 CFR 908.7101-2 - Consolidated acquisition of new vehicles by General Services Administration.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Consolidated acquisition of new vehicles by General Services Administration. 908.7101-2 Section 908.7101-2 Federal Acquisition Regulations System DEPARTMENT OF ENERGY COMPETITION ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Acquisition of Special...

  17. Coupled Fluids-Radiation Analysis of a High-Mass Mars Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Palmer, Grant; Allen, Gary; Tang, Chun; Brown, Jim

    2011-01-01

    The NEQAIR line-by-line radiation code has been incorporated into the DPLR Navier-Stokes flow solver such that the NEQAIR subroutines are now callable functions of DPLR. The coupled DPLR-NEQAIR code was applied to compute the convective and radiative heating rates over high-mass Mars entry vehicles. Two vehicle geometries were considered - a 15 m diameter 70-degree sphere cone configuration and a slender, mid-L/D vehicle with a diameter of 5 m called an Ellipsled. The entry masses ranged from 100 to 165 metric tons. Solutions were generated for entry velocities ranging from 6.5 to 9.1 km/s. The coupled fluids-radiation solutions were performed at the peak heating location along trajectories generated by the Traj trajectory analysis code. The impact of fluids-radiation coupling is a function of the level of radiative heating and the freestream density and velocity. For the high-mass Mars vehicles examined in this study, coupling effects were greatest for entry velocities above 8.5 km/s where the surface radiative heating was reduced by up 17%. Generally speaking, the Ellipsled geometry experiences a lower peak radiative heating rate but a higher peak turbulent convective heating rate than the MSL-based vehicle.

  18. Mesh-Based Entry Vehicle and Explosive Debris Re-Contact Probability Modeling

    NASA Technical Reports Server (NTRS)

    McPherson, Mark A.; Mendeck, Gavin F.

    2011-01-01

    The risk to a crewed vehicle arising from potential re-contact with fragments from an explosive breakup of any jettisoned spacecraft segments during entry has long sought to be quantified. However, great difficulty lies in efficiently capturing the potential locations of each fragment and their collective threat to the vehicle. The method presented in this paper addresses this problem by using a stochastic approach that discretizes simulated debris pieces into volumetric cells, and then assesses strike probabilities accordingly. Combining spatial debris density and relative velocity between the debris and the entry vehicle, the strike probability can be calculated from the integral of the debris flux inside each cell over time. Using this technique it is possible to assess the risk to an entry vehicle along an entire trajectory as it separates from the jettisoned segment. By decoupling the fragment trajectories from that of the entry vehicle, multiple potential separation maneuvers can then be evaluated rapidly to provide an assessment of the best strategy to mitigate the re-contact risk.

  19. International Space Station as an Observation Platform for Hypersonic Re-Entry of its Visiting Vehicles

    NASA Technical Reports Server (NTRS)

    Bacon, John B.

    2001-01-01

    The International Space Station (ISS) will receive an armada of visiting supply vehicles during its life in orbit. Over 500 tons of material will be destroyed in targeted re-entries of these vehicles. Because all such re-entries lie in the same orbital plane of the station, and because the visiting vehicles typically deorbit within a few hours of departure, the ISS will usually be within sight of the re-entry process, at a range of only 300-600 kilometers. This vantage point offers an unprecedented opportunity for systematically measuring hypersonic destructive processes. This paper examines the integrated operational constraints of the ISS, its supply vehicles, and candidate sensors which can be employed in the scientific observation of the re-entry process. It is asserted the ISS program has the potential to reduce the worldwide risks from future deorbiting spacecraft, through systematic experimental characterization of the factors which affect the rupture, debris survival, and footprint size of its visiting vehicle fleet.

  20. Virtual Reality Modelling Simulation of the Re-entry Motion of an Axialsymmetric Vehicle

    NASA Astrophysics Data System (ADS)

    Guidi, A.; Chu, Q.. P.; Mulder, J. A.

    This work started during the stability analysis of the Delft Aerospace Re-entry Test demonstrator (DART) which is a small axisymmetric ballistic re-entry vehicle. The dynamic stability evaluation of an axisymmetric re-entry vehicle is especially concerned on the behaviour of its angle of attack during the flight through the atmosphere. The variation in the angle of attack is essential for prediction of the trajectory of the vehicle and for heating requirement of the structure of the vehicle. The concept of the total angle of attack and the windward meridian plane are introduced. The position of the centre of pressure can be a crucial point in the stability of the vehicle. Although the simpleness of an axisymmetric shape, the re-entry of such a vehicle is characterised by several complex phenomenologies that were analysed with the aid of the flight simulator and of a 3D virtual reality modeling simulator. Simulations were performed with a 25° AOA initial condition in order to simulate the response of the vehicle to a disturbance that may occur during the flight causing a variation in attitude from its Trim . Certain aspects of re-entry vehicle motion are conveniently described in the terms of Euler angles. Using the Eulerian angle it is possible to generate a tridimensional animation of the output of the Flight Simulator. This tridimensional analysis is of great importance in order to understand the mentioned complex motions. Furthermore with growing in computer power it is possible to generate online visualisation of the simulations. The output of the flight simulator was used in a software written in Virtual Reality Modelling Language (VRML). With VRML this software was possible the visualisation of the re-entry motion of the vehicle. With this option the animation can run on-line during the with the flight simulator and can be also easily published on the internet or send to other users in very small file size. (the VRLM simulation of the re-entry, can be seen

  1. Wake Flow About the Mars Pathfinder Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Mitcheltree, R. A.; Gnoffo, P. A.

    1995-01-01

    A computational approach is used to describe the aerothermodynamics of the Mars Pathfinder vehicle entering the Mars atmosphere at the maximum heating and maximum deceleration points in its trajectory. Ablating and nonablating boundary conditions are developed which produce maximum recombination of CO2 on the surface. For the maximum heating trajectory point, an axisymmetric, nonablating calculation predicts a stagnation-point value for the convective heating of 115 W/cm(exp 2). Radiative heating estimates predict an additional 5-12 W/cm(exp 2) at the stagnation point. Peak convective heating on the afterbody occurs on the vehicle's flat stern with a value of 5.9% of the stagnation value. The forebody flow exhibits chemical nonequilibrium behavior, and the flow is frozen in the near wake. Including ablation injection on the forebody lowers the stagnation-point convective heating 18%.

  2. Integrated Design System (IDS) Tools for the Spacecraft Aeroassist/Entry Vehicle Design Process

    NASA Technical Reports Server (NTRS)

    Olynick, David; Braun, Robert; Langhoff, Steven R. (Technical Monitor)

    1997-01-01

    The definition of the Integrated Design System technology focus area as presented in the NASA Information Technology center of excellence strategic plan is described. The need for IDS tools in the aeroassist/entry vehicle design process is illustrated. Initial and future plans for spacecraft IDS tool development are discussed.

  3. Vertical Spin Tunnel Testing and Stability Analyses of Earth Entry Vehicles

    NASA Astrophysics Data System (ADS)

    Glaab, L. J.; Fremaux, C. M.

    2014-06-01

    This report presents results from dynamic stability testing in the NASA LaRC Vertical Spin Tunnel of a series of Multi-Mission Earth Entry Vehicles and subsequent data analysis. Evaluation of a proposed dynamic stability criteria is also performed.

  4. An assessment of the impact of transition on advanced winged entry vehicle thermal protection system mass

    NASA Technical Reports Server (NTRS)

    Wurster, K. E.

    1981-01-01

    This study examines the impact of turbulent heating on thermal protection system (TPS) mass for advanced winged entry vehicles. Four basic systems are considered: insulative, metallic hot structures, metallic standoff, and hybrid systems. TPS sizings are performed using entry trajectories tailored specifically to the characteristics of each TPS concept under consideration. Comparisons are made between systems previously sized under the assumption of all laminar heating and those sized using a baseline estimate of transition and turbulent heating. The relative effect of different transition criteria on TPS mass requirements is also examined. Also investigated are entry trajectories tailored to alleviate turbulent heating. Results indicate the significant impact of turbulent heating on TPS mass and demonstrate the importance of both accurate transition criteria and entry trajectory tailoring.

  5. Atmospheric entry of nuclear-powered vehicles due to accidental/inadvertent termination of operations

    NASA Technical Reports Server (NTRS)

    Menees, Gene P.; Park, Chul; Tauber, Michael E.

    1992-01-01

    The entries of the radioactive components into earth's atmosphere resulting from an accident or inadvertent abort of a space vehicle powered by nuclear-thermal-rockets are investigated. The study is made for a typical piloted Mars mission vehicle incapacitated by an accident or malfunction during the trans-Mars-injection maneuver due to simultaneous multiple failures of its component systems. The three different accident/abort modes considered are the following: (1) a constant-rate angular pitching motion of the vehicle, (2) a constant-acceleration angular pitching motion of the vehicle, and (3) the rocket engine breaks away from the rest of the vehicle with a finite relative (dispersion) velocity. The speeds and angles of the atmospheric entries are calculated for each mode for different values of the time of the accident, pitching rate, acceleration, and dispersion velocity. For the most severe entry speeds and flight-path angles, the stagnation-point pressures, heat transfer rates, thickness, and mass per unit area of the heat shields necessary to protect the radioactive components from disintegrating, deceleration g-loads, and high ground-impact velocities are calculated. The study points out that the high g-loads and high ground-impact velocities are the most serious problems that must be addressed.

  6. Re-entry vehicle shape for enhanced performance

    NASA Technical Reports Server (NTRS)

    Brown, James L. (Inventor); Garcia, Joseph A. (Inventor); Prabhu, Dinesh K. (Inventor)

    2008-01-01

    A convex shell structure for enhanced aerodynamic performance and/or reduced heat transfer requirements for a space vehicle that re-enters an atmosphere. The structure has a fore-body, an aft-body, a longitudinal axis and a transverse cross sectional shape, projected on a plane containing the longitudinal axis, that includes: first and second linear segments, smoothly joined at a first end of each the first and second linear segments to an end of a third linear segment by respective first and second curvilinear segments; and a fourth linear segment, joined to a second end of each of the first and second segments by curvilinear segments, including first and second ellipses having unequal ellipse parameters. The cross sectional shape is non-symmetric about the longitudinal axis. The fourth linear segment can be replaced by a sum of one or more polynomials, trigonometric functions or other functions satisfying certain constraints.

  7. Aerodynamic comparisons of STS-1 Space Shuttle entry vehicle

    NASA Technical Reports Server (NTRS)

    Young, J. C.

    1982-01-01

    A conventional flight-test program, which slowly and cautiously approaches more severe flight conditions, was not possible with the Orbiter. On the first flight, the Orbiter entered the atmosphere at Mach 28 and decelerated through the Mach range. (The subsonic portion of flight was also flown by another orbiter vehicle during the Approach and Landing Test Program.) Certification for the first flight was achieved by an extensive wind-tunnel test and analysis program and by restricting the flight maneuvers severely. The initial flights of the orbiter were heavily instrumented for the purpose of obtaining accurate aerodynamic data. Even without maneuvers to excite the system, the first flight provided comparisons between flight and wind-tunnel-derived predicted data in the areas of aerodynamic performance, longitudinal trim, and reaction-control jet interaction. The aerodynamic performance comparisons are presented.

  8. Fiber Optic High Temperature Sensors for Re-Entry Vehicles

    NASA Astrophysics Data System (ADS)

    Haddad, E.; Kruzelecky, R.; Zou, J.; Wong, B.; Jamroz, W.; Sayeed, F.; Muylaert, J.-M.; McKenzie, I.

    2009-01-01

    MPB, within an ESA contract, is developing high temperature Fiber sensors (up to 1100°C) for re- ntry experiments, with direct application to the Thermo Protection Surface (TPS) of SHEFEX II. It addresses the challenges of obtaining high reflectivity FBG sensors, and integrating the fiber sensors within the selected TPS host material (C/SiC). Feasibility was demonstrated using free fiber sensors that showed the formation of the Chemical Composition Grating (CCG), with 80 % reflection at temperatures >750°C. The CCG grating was stable at high temperature (1000°C) for more than 50 hours, as well as after cycling between room temperature and 1000°C, with better than 0.5 % temperature accuracy (FBG central wavelength). Small FBG sensor packages were prepared and attached to C/SiC tiles. The calibration of the packaged fibers showed similar response to temperature as the free fiber sensor. The fiber sensor package was designed to maximize contact with the C/SiC surface to provide fast response to transients. Three- imension modeling with Ansys finite element analysis shows a time constant of 15-20 ms to reach 1200°C. A modular design will be implemented where a dedicated fiber line with 3 sensors and its own connector is used for each C/SiC tile. Small coupons of packaged sensors attached to C/SiC tiles will be tested in a re-entry environment at Von Karman Institute (Belgium) In a recently completed project with ESA, MPB developed and ground qualified a fiber sensor network, the "Fiber Sensor Demonstrator", that was successfully integrated as a payload with ESA's Proba-2. The system includes a central interrogation system that can be used to measure multiple parameters including a high temperature sensor for the Proba-2 thruster (up to 500°C).

  9. Earth Entry Vehicle Design for Sample Return Missions Using M-SAPE

    NASA Technical Reports Server (NTRS)

    Samareh, Jamshid

    2015-01-01

    Most mission concepts that return sample material to Earth share one common element: an Earth entry vehicle (EEV). The primary focus of this paper is the examination of EEV design space for relevant sample return missions. Mission requirements for EEV concepts can be divided into three major groups: entry conditions (e.g., velocity and flight path angle), payload (e.g., mass, volume, and g-load limit), and vehicle characteristics (e.g., thermal protection system, structural topology, and landing concepts). The impacts of these requirements on the EEV design have been studied with an integrated system analysis tool, and the results will be discussed in details. In addition, through sensitivities analyses, critical design drivers that have been identified will be reviewed.

  10. Advanced Aero-Propulsive Mid-Lift-to-Drag Ratio Entry Vehicle for Future Exploration Missions

    NASA Technical Reports Server (NTRS)

    Campbell, C. H.; Stosaric, R. R; Cerimele, C. J.; Wong, K. A.; Valle, G. D.; Garcia, J. A.; Melton, J. E.; Munk, M. M.; Blades, E.; Kuruvila, G.; Picetti, D. J.; Hassan, B.; Kniskern, M. W.

    2012-01-01

    NASA is currently looking well into the future toward realizing Exploration mission possibilities to destinations including the Earth-Moon Lagrange points, Near-Earth Asteroids (NEAs) and the Moon. These are stepping stones to our ultimate destination Mars. New ideas will be required to conquer the significant challenges that await us, some just conceptions and others beginning to be realized. Bringing these ideas to fruition and enabling further expansion into space will require varying degrees of change, from engineering and integration approaches used in spacecraft design and operations, to high-level architectural capabilities bounded only by the limits of our ideas. The most profound change will be realized by paradigm change, thus enabling our ultimate goals to be achieved. Inherent to achieving these goals, higher entry, descent, and landing (EDL) performance has been identified as a high priority. Increased EDL performance will be enabled by highly-capable thermal protection systems (TPS), the ability to deliver larger and heavier payloads, increased surface access, and tighter landing footprints to accommodate multiple asset, single-site staging. In addition, realizing reduced cost access to space will demand more efficient approaches and reusable launch vehicle systems. Current operational spacecraft and launch vehicles do not incorporate the technologies required for these far-reaching missions and goals, nor what is needed to achieve the desired launch vehicle cost savings. To facilitate these missions and provide for safe and more reliable capabilities, NASA and its partners will need to make ideas reality by gaining knowledge through the design, development, manufacturing, implementation and flight testing of robotic and human spacecraft. To accomplish these goals, an approach is recommended for integrated development and implementation of three paradigm-shifting capabilities into an advanced entry vehicle system with additional application to launch

  11. Missions to Titan /1983-2000/ - An analysis of orbiters and entry vehicles

    NASA Technical Reports Server (NTRS)

    Hendricks, T. C.; Satin, A. L.; Tindle, E.

    1976-01-01

    Mission Analysis data is presented which forms a basis for planning future missions to Titan, the seventh moon of Saturn. Four Titan mission options are studied: orbiters, probes, penetrators and landers. The generated data supports these mission modes. A comprehensive launch and trajectory analysis of earth to Saturn opportunities from 1983 to 2000 is given. Direct ballistic and Delta VEGA trajectory modes are evaluated. Orbital insertion, orbital trim, entry vehicle deployment options are all studied in parametric detail.

  12. 10 CFR 490.201 - Alternative fueled vehicle acquisition mandate schedule.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Alternative fueled vehicle acquisition mandate schedule. 490.201 Section 490.201 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Mandatory State Fleet Program § 490.201 Alternative fueled vehicle acquisition...

  13. 10 CFR 490.201 - Alternative fueled vehicle acquisition mandate schedule.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Alternative fueled vehicle acquisition mandate schedule. 490.201 Section 490.201 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Mandatory State Fleet Program § 490.201 Alternative fueled vehicle acquisition...

  14. 10 CFR 490.201 - Alternative fueled vehicle acquisition mandate schedule.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Alternative fueled vehicle acquisition mandate schedule. 490.201 Section 490.201 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Mandatory State Fleet Program § 490.201 Alternative fueled vehicle acquisition...

  15. 10 CFR 490.201 - Alternative fueled vehicle acquisition mandate schedule.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Alternative fueled vehicle acquisition mandate schedule. 490.201 Section 490.201 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Mandatory State Fleet Program § 490.201 Alternative fueled vehicle acquisition...

  16. 10 CFR 490.201 - Alternative fueled vehicle acquisition mandate schedule.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Alternative fueled vehicle acquisition mandate schedule. 490.201 Section 490.201 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Mandatory State Fleet Program § 490.201 Alternative fueled vehicle acquisition...

  17. Assessment of the Reconstructed Aerodynamics of the Mars Science Laboratory Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Schoenenberger, Mark; Van Norman, John W.; Dyakonov, Artem A.; Karlgaard, Christopher D.; Way, David W.; Kutty, Prasad

    2013-01-01

    On August 5, 2012, the Mars Science Laboratory entry vehicle successfully entered Mars atmosphere, flying a guided entry until parachute deploy. The Curiosity rover landed safely in Gale crater upon completion of the Entry Descent and Landing sequence. This paper compares the aerodynamics of the entry capsule extracted from onboard flight data, including Inertial Measurement Unit (IMU) accelerometer and rate gyro information, and heatshield surface pressure measurements. From the onboard data, static force and moment data has been extracted. This data is compared to preflight predictions. The information collected by MSL represents the most complete set of information collected during Mars entry to date. It allows the separation of aerodynamic performance from atmospheric conditions. The comparisons show the MSL aerodynamic characteristics have been identified and resolved to an accuracy better than the aerodynamic database uncertainties used in preflight simulations. A number of small anomalies have been identified and are discussed. This data will help revise aerodynamic databases for future missions and will guide computational fluid dynamics (CFD) development to improved prediction codes.

  18. Mars Sample Return Using Commercial Capabilities: Propulsive Entry, Descent, and Landing of a Capsule Form Vehicle

    NASA Technical Reports Server (NTRS)

    Gonzales, Andrew A.; Lemke, Lawrence G.; Huynh, Loc C.

    2014-01-01

    This paper describes a critical portion of the work that has been done at NASA, Ames Research Center regarding the use of the commercially developed Dragon capsule as a delivery vehicle for the elements of a high priority Mars Sample Return mission. The objective of the investigation was to determine entry and landed mass capabilities that cover anticipated mission conditions. The "Red Dragon", Mars configuration, uses supersonic retro-propulsion, with no required parachute system, to perform Entry, Descent, and Landing (EDL) maneuvers. The propulsive system proposed for use is the same system that will perform an abort, if necessary, for a human rated version of the Dragon capsule. Standard trajectory analysis tools are applied to publically available information about Dragon and other legacy capsule forms in order to perform the investigation. Trajectory simulation parameters include entry velocity, flight path angle, lift to drag Ratio (L/D), landing site elevation, atmosphere density, and total entry mass, in addition engineering assumptions for the performance of the propulsion system are stated. Mass estimates for major elements of the overall proposed architecture are coupled to this EDL analysis to close the overall architecture. Three synodic launch opportunities, beginning with the 2022 opportunity, define the arrival conditions. Results state the relations between the analysis parameters as well as sensitivities to those parameters. The EDL performance envelope includes landing altitudes between 0 and -4 km referenced to the Mars Orbiter Laser Altimeter datum as well as minimum and maximum atmosphere density. Total entry masses between 7 and 10 mt are considered with architecture closure occurring between 9.0 and 10 mt. Propellant mass fractions for each major phase of the EDL - Entry, Terminal Descent, and Hazard Avoidance - have been derived. An assessment of the effect of the entry conditions on the Thermal Protection System (TPS) currently in use for

  19. Vertical Spin Tunnel Testing and Stability Analysis of Multi-Mission Earth Entry Vehicles

    NASA Technical Reports Server (NTRS)

    Glaab, Louis J.; Morelli, Eugene A.; Fremaux, C. Michael; Bean, Jacob

    2014-01-01

    Multi-Mission Earth Entry Vehicles (MMEEVs) are blunt-body vehicles designed with the purpose of transporting payloads from space to the surface of the Earth. To achieve high reliability and minimum weight, MMEEVs avoid using 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 phases of flight. Testing in NASA Langley's 20-FT Vertical Spin Tunnel (20-FT VST), dynamically-scaled MMEEV models was conducted to improve subsonic aerodynamic models and validate stability criteria for this class of vehicle. This report documents the resulting data from VST testing for an array of 60-deg sphere-cone MMEEVs. Model configurations included were 1.2 meter, and 1.8 meter designs. The addition of a backshell extender, which provided a 150% increase in backshell diameter for the 1.2 meter design, provided a third test configuration. Center of Gravity limits were established for all MMEEV configurations. An application of System Identification (SID) techniques was performed to determine the aerodynamic coefficients in order to provide databases for subsequent 6-degree-of-freedom simulations.

  20. Laminar, Transitional, and Turbulent Heating on Mid Lift-to-Drag Ratio Entry Vehicles

    NASA Technical Reports Server (NTRS)

    Hollis, Brian R.; Hollingsworth, Kevin E.

    2013-01-01

    The boundary-layer transition characteristics and convective aeroheating levels on mid lift-to-drag ratio entry vehicle configurations have been studied through wind-tunnel testing. Several configurations were investigated, including elliptically blunted cylinders with both circular and elliptically flattened cross sections, biconic geometries based on launch vehicle dual-use shrouds, and parametrically optimized analytic geometries. Vehicles of this class have been proposed for high-mass Mars missions, such as sample return and crewed exploration, for which the conventional sphere-cone entry-vehicle geometries of previous Mars missions are insufficient. Testing was conducted at Mach 6 over a range of Reynolds numbers sufficient to generate laminar, transitional, and turbulent flow. Transition onset locations, both straight-line and cross-flow, and heating rates were obtained through global phosphor thermography. Supporting computations were performed to obtain heating rates for comparison with the data. Laminar data and predictions agreed to well within the experimental uncertainty. Fully turbulent data and predictions also agreed well. However, in transitional flow regions, greater differences were observed.

  1. Laminar, Transitional, and Turbulent Heating on Mid Lift-to-Drag Ratio Entry Vehicles

    NASA Technical Reports Server (NTRS)

    Hollis, Brian R.; Hollingsworth, Kevin E.

    2012-01-01

    The boundary-layer transition characteristics and convective aeroheating levels on mid lift-to-drag ratio entry vehicle configurations have been studied through wind tunnel testing. Several configurations were investigated, including elliptically-blunted cylinders with both circular and elliptically-flattened cross sections, biconic geometries based on launch vehicle dual-use shrouds, and parametrically-optimized analytic geometries. Vehicles of this class have been proposed for high-mass Mars missions, such as sample return and crewed exploration, for which the conventional sphere-cone entry-vehicle geometries of previous Mars missions are insufficient. Testing was conducted at Mach 6 over a range of Reynolds numbers sufficient to generate laminar, transitional, and turbulent flow. Transition onset locations - both straight-line and cross-flow - and heating rates were obtained through global phosphor thermography. Supporting computations were performed to obtain heating rates for comparison with the data. Laminar data and predictions agreed to well within the experimental uncertainty. Fully-turbulent data and predictions also agreed well. However, in transitional flow regions, greater differences were observed. Additional aerodynamic performance data were also generated through Modified-Newtonian analyses of the geometries.

  2. 48 CFR 908.7101-6 - Acquisition of fuel-efficient vehicles.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 41 CFR 109-38.13.) (b) Sedans, station wagons, and light trucks requisitioned according to an... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Acquisition of fuel... Items 908.7101-6 Acquisition of fuel-efficient vehicles. (a) All purchases of sedans and station...

  3. 48 CFR 908.7101-6 - Acquisition of fuel-efficient vehicles.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Acquisition of fuel... Items 908.7101-6 Acquisition of fuel-efficient vehicles. (a) All purchases of sedans and station wagons... Activities will submit annually to the Director, Personal Property Policy Division, within the...

  4. 48 CFR 908.7101-6 - Acquisition of fuel-efficient vehicles.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Acquisition of fuel... Items 908.7101-6 Acquisition of fuel-efficient vehicles. (a) All purchases of sedans and station wagons... Activities will submit annually to the Director, Personal Property Policy Division, within the...

  5. 48 CFR 908.7101-6 - Acquisition of fuel-efficient vehicles.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Acquisition of fuel-efficient vehicles. 908.7101-6 Section 908.7101-6 Federal Acquisition Regulations System DEPARTMENT OF... Activities will submit annually to the Director, Office of Property Management, within the...

  6. 48 CFR 908.7101-6 - Acquisition of fuel-efficient vehicles.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Acquisition of fuel-efficient vehicles. 908.7101-6 Section 908.7101-6 Federal Acquisition Regulations System DEPARTMENT OF... Activities will submit annually to the Director, Office of Property Management, within the...

  7. Ascent, abort, and entry capability assessment of a Space Station rescue and personnel/logistics vehicle

    NASA Technical Reports Server (NTRS)

    Naftel, J. C.; Powell, R. W.; Talay, T. A.

    1989-01-01

    The ascent, abort, and entry capability of a vehicle for rescue of the Space Station crew or ferry of personnel and supplies to and from the Space Station are analyzed. The configurations of the Space Station rescue vehicle and the Space Station personnel/logistics vehicle (SSPLV) are discussed and illustrated. The nominal ascent trajectory for the SSPLV delivered to orbit on a Titan II is presented. The ascent abort modes from launch to orbital injection are evaluated. It is shown that five landing sites with runways longer than 10,000 ft could provide a landing opportunity from every orbit of the Space Station in a 220-nmi circular orbit with a 28.5 deg inclination.

  8. Dynamic and Static High Temperature Resistant Ceramic Seals for X- 38 re-Entry Vehicle

    NASA Astrophysics Data System (ADS)

    Handrick, Karin E.; Curry, Donald M.

    2002-01-01

    In a highly successful partnership, NAS A, ESA, DLR (German Space Agency) and European industry are building the X-38, V201 re-entry spacecraft, the prototype of the International Space Station's Crew Return Vehicle (CRV). This vehicle would serve both as an ambulance for medical emergencies and as an evacuation vehicle for the Space Station. The development of essential systems and technologies for a reusable re-entry vehicle is a first for Europe, and sharing the development of an advanced re-entry spacecraft with foreign partners is a first for NASA. NASA, in addition to its subsystem responsibilities, is performing overall X-38 vehicle system engineering and integration, will launch V201 on the Space Shuttle, deliver flight data for post-flight analysis and assessment and is responsible for development and manufacture of structural vehicle components and thermal protection (TPS) tiles. The major European objective for cooperation with NASA on X-38 was to establish a clear path through which key technologies needed for future space transportation systems could be developed and validated at affordable cost and with controlled risk. Europe has taken the responsibility to design and manufacture hot control surfaces like metallic rudders and ceramic matrix composites (CMC) body flaps, thermal protection systems such as CMC leading edges, the CMC nose cap and -skirt, insulation, landing gears and elements of the V201 primary structure. Especially hot control surfaces require extremely high temperature resistant seals to limit hot gas ingestion and transfer of heat to underlying low-temperature structures to prevent overheating of these structures and possible loss of the vehicle. Complex seal interfaces, which have to fulfill various, tight mission- and vehicle-related requirements exist between the moveable ceramic body flaps and the bottom surface of the vehicle, between the rudder and fin structure and the ceramic leading edge panel and TPS tiles. While NASA

  9. Atmospheric entry of Mars-return nuclear-powered vehicles due to accidental termination of operations

    NASA Astrophysics Data System (ADS)

    Menees, Gene P.; Park, Chul

    1993-06-01

    The entry of nuclear reactors into Earth's atmosphere resulting from an accidental or inadvertent abort of a space vehicle powered by nuclear-thermal rockets is investigated. The study is made for a typical piloted Mars mission vehicle incapacitated by an accident or malfunction during the Earth-arrival phase of the Mars-return journey due to simultaneous, multiple failures of its component systems. A single accident/abort scenario resulting in three entry possibilities is considered for a nominal hyperbolic in-bound approach velocity of 8 km/sec. The most severe case involving a direct entry is then analyzed over a broad range of approach velocities extending to 12 km/sec to include sprint-type missions. The results indicate that the severe surface heating, stagnation pressures, and g-loads are greater than 150 kW/sq cm, 300 atm, and 800-g, respectively. The wall heat transfer rate exceeds the value that can be accommodated by a carbon heatshield through radiation equilibrium prior to sublimation at 5500 K. These conditions are beyond our previous experience in crew safety, structural design, and thermal protection.

  10. Atmospheric entry of Mars-return nuclear-powered vehicles due to accidental termination of operations

    NASA Technical Reports Server (NTRS)

    Menees, Gene P.; Park, Chul

    1993-01-01

    The entry of nuclear reactors into Earth's atmosphere resulting from an accidental or inadvertent abort of a space vehicle powered by nuclear-thermal rockets is investigated. The study is made for a typical piloted Mars mission vehicle incapacitated by an accident or malfunction during the Earth-arrival phase of the Mars-return journey due to simultaneous, multiple failures of its component systems. A single accident/abort scenario resulting in three entry possibilities is considered for a nominal hyperbolic in-bound approach velocity of 8 km/sec. The most severe case involving a direct entry is then analyzed over a broad range of approach velocities extending to 12 km/sec to include sprint-type missions. The results indicate that the severe surface heating, stagnation pressures, and g-loads are greater than 150 kW/sq cm, 300 atm, and 800-g, respectively. The wall heat transfer rate exceeds the value that can be accommodated by a carbon heatshield through radiation equilibrium prior to sublimation at 5500 K. These conditions are beyond our previous experience in crew safety, structural design, and thermal protection.

  11. Impact Foam Testing for Multi-Mission Earth Entry Vehicle Applications

    NASA Technical Reports Server (NTRS)

    Glaab, Louis J.; Agrawal, Paul; Hawbaker, James

    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 and retro-rockets, instead using built-in impact attenuators to absorb energy remaining at impact to meet landing loads requirements. The Multi-Mission Systems Analysis for Planetary Entry (M-SAPE) parametric design tool is used to facilitate the design of MMEEVs and develop the trade space. Testing was conducted to characterize the material properties of several candidate impact foam attenuators to enhance M-SAPE analysis. In the current effort, two different Rohacell foams were tested to determine their thermal conductivity in support of MMEEV design applications. These applications include thermal insulation during atmospheric entry, impact attenuation, and post-impact thermal insulation in support of thermal soak analysis. Results indicate that for these closed-cell foams, the effect of impact is limited on thermal conductivity due to the venting of the virgin material gas and subsequent ambient air replacement. Results also indicate that the effect of foam temperature is significant compared to data suggested by manufacturer's specifications.

  12. Problems of control of a re-entry vehicle with a moderate lift-to-drag ratio during its entry into the atmosphere

    NASA Astrophysics Data System (ADS)

    Bobylev, A. V.; Dyad'Kin, A. A.; Kobzev, V. I.; Poedinok, V. M.; Reshetin, A. G.; Suprunenko, S. N.; Jaroshevskii, V. A.

    2008-02-01

    We consider the problems of control of the angular and trajectory motion of the Kliper re-entry vehicle. This spacecraft with a moderate hypersonic lift-to-drag ratio is designed according to the load-carrying frame scheme. Gas-dynamic engines, a split balancing flap, and an air brake are used as mounting devices of control.

  13. Longitudinal control effectiveness and entry dynamics of a single-stage-to-orbit vehicle

    NASA Technical Reports Server (NTRS)

    Vinh, N. X.; Lin, C. F.

    1982-01-01

    The classical theory of flight dynamics for airplane longitudinal stability and control analysis was extended to the case of a hypervelocity reentry vehicle. This includes the elements inherent in supersonic and hypersonic flight such as the influence of the Mach number on aerodynamic characteristics, and the effect of the reaction control system and aerodynamic controls on the trim condition through a wide range of speed. Phugoid motion and angle of attack oscillation for typical cases of cruising flight, ballistic entry, and glide entry are investigated. In each case, closed form solutions for the variations in altitude, flight path angle, speed and angle of attack are obtained. The solutions explicitly display the influence of different regions design parameters and trajectory variables on the stability of the motion.

  14. Assessment of Laminar, Convective Aeroheating Prediction Uncertainties for Mars Entry Vehicles

    NASA Technical Reports Server (NTRS)

    Hollis, Brian R.; Prabhu, Dinesh K.

    2011-01-01

    An assessment of computational uncertainties is presented for numerical methods used by NASA to predict laminar, convective aeroheating environments for Mars entry vehicles. A survey was conducted of existing experimental heat-transfer and shock-shape data for high enthalpy, reacting-gas CO2 flows and five relevant test series were selected for comparison to predictions. Solutions were generated at the experimental test conditions using NASA state-of-the-art computational tools and compared to these data. The comparisons were evaluated to establish predictive uncertainties as a function of total enthalpy and to provide guidance for future experimental testing requirements to help lower these uncertainties.

  15. Assessment of Laminar, Convective Aeroheating Prediction Uncertainties for Mars-Entry Vehicles

    NASA Technical Reports Server (NTRS)

    Hollis, Brian R.; Prabhu, Dinesh K.

    2013-01-01

    An assessment of computational uncertainties is presented for numerical methods used by NASA to predict laminar, convective aeroheating environments for Mars-entry vehicles. A survey was conducted of existing experimental heat transfer and shock-shape data for high-enthalpy reacting-gas CO2 flows, and five relevant test series were selected for comparison with predictions. Solutions were generated at the experimental test conditions using NASA state-of-the-art computational tools and compared with these data. The comparisons were evaluated to establish predictive uncertainties as a function of total enthalpy and to provide guidance for future experimental testing requirements to help lower these uncertainties.

  16. Rudder/Fin Seals Investigated for the X-38 Re-Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Dunlap, Patrick H., Jr.; Steinetz, Bruce M.

    2002-01-01

    NASA is developing the X-38 vehicle that will demonstrate the technologies required for a potential crew return vehicle for the International Space Station. This vehicle would serve both as an ambulance for medical emergencies and as an evacuation vehicle for the space station. Control surfaces on the X-38 (body flaps and rudder/fin assemblies) require high temperature seals to limit hot gas ingestion and the transfer of heat to underlying low temperature structures. Working with the NASA Johnson Space Center, the Seals Team at the NASA Glenn Research Center completed a series of tests to further characterize baseline seal designs for the rudder/fin interfaces of the X-38. The structures of the rudder/fin assembly and its associated seals are shown in the the preceding illustration. Tests performed at Glenn indicated that exposure of the seals in a compressed state at simulated seal re-entry temperatures resulted in a large permanent set and loss of seal resiliency. This could be of concern because the seals are required to maintain contact with the sealing surfaces while the vehicle goes through the maximum re-entry heating cycle to prevent hot gases from leaking past the seals and damaging interior low-temperature structures. To simulate conditions in which the seals may become unloaded during use, such as when they take on a large permanent set, Glenn researchers performed room temperature flow and compression tests to determine seal flow rates, resiliency, and unit loads under minimal loads. Flow rates through an unloaded (i.e., 0-percent compression) double seal arrangement were twice those of a double seal compressed to the 20-percent design compression level. These flow rates are being used in thermal analyses to predict the effect of flow through the seals on over-all seal temperatures. Compression test results showed that seal unit loads and contact pressures were below the limits that Johnson had set as goals for the seals. In the rudder/fin seal location

  17. Blunt-Body Entry Vehicle Aerothermodynamics: Transition and Turbulence on the CEV and MSL Configurations

    NASA Technical Reports Server (NTRS)

    Hollis, Brian R.

    2010-01-01

    Recent, current, and planned NASA missions that employ blunt-body entry vehicles pose aerothermodynamic problems that challenge the state-of-the art of experimental and computational methods. The issues of boundary-layer transition and turbulent heating on the heat shield have become important in the designs of both the Mars Science Laboratory and Crew Exploration Vehicle. While considerable experience in these general areas exists, that experience is mainly derived from simple geometries; e.g. sharp-cones and flat-plates, or from lifting bodies such as the Space Shuttle Orbiter. For blunt-body vehicles, application of existing data, correlations, and comparisons is questionable because an all, or mostly, subsonic flow field is produced behind the bow shock, as compared to the supersonic (or even hypersonic) flow of other configurations. Because of the need for design and validation data for projects such as MSL and CEV, many new experimental studies have been conducted in the last decade to obtain detailed boundary-layer transition and turbulent heating data on this class of vehicle. In this paper, details of several of the test programs are reviewed. The laminar and turbulent data from these various test are shown to correlate in terms of edge-based Stanton and Reynolds number functions. Correlations are developed from the data for transition onset and turbulent heating augmentation as functions of momentum thickness Reynolds number. These correlation can be employed as engineering-level design and analysis tools.

  18. Challenges to Computational Aerothermodynamic Simulation and Validation for Planetary Entry Vehicle Analysis

    NASA Technical Reports Server (NTRS)

    Gnoffo, Peter A.; Johnston, Christopher O.; Kleb, Bil

    2010-01-01

    Challenges to computational aerothermodynamic (CA) simulation and validation of hypersonic flow over planetary entry vehicles are discussed. Entry, descent, and landing (EDL) of high mass to Mars is a significant driver of new simulation requirements. These requirements include simulation of large deployable, flexible structures and interactions with reaction control system (RCS) and retro-thruster jets. Simulation of radiation and ablation coupled to the flow solver continues to be a high priority for planetary entry analyses, especially for return to Earth and outer planet missions. Three research areas addressing these challenges are emphasized. The first addresses the need to obtain accurate heating on unstructured tetrahedral grid systems to take advantage of flexibility in grid generation and grid adaptation. A multi-dimensional inviscid flux reconstruction algorithm is defined that is oriented with local flow topology as opposed to grid. The second addresses coupling of radiation and ablation to the hypersonic flow solver - flight- and ground-based data are used to provide limited validation of these multi-physics simulations. The third addresses the challenges of retro-propulsion simulation and the criticality of grid adaptation in this application. The evolution of CA to become a tool for innovation of EDL systems requires a successful resolution of these challenges.

  19. Uniform Foam Crush Testing for Multi-Mission Earth Entry Vehicle Impact Attenuation

    NASA Technical Reports Server (NTRS)

    Patterson, Byron W.; Glaab, Louis J.

    2012-01-01

    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 and retro-rockets, instead using built-in impact attenuators to absorb energy remaining at impact to meet landing loads requirements. The Multi-Mission Systems Analysis for Planetary Entry (M-SAPE) parametric design tool is used to facilitate the design of MMEEVs and develop the trade space. Testing was conducted to characterize the material properties of several candidate impact foam attenuators to enhance M-SAPE analysis. In the current effort, four different Rohacell foams are tested at three different, uniform, strain rates (approximately 0.17, approximately 100, approximately 13,600%/s). The primary data analysis method uses a global data smoothing technique in the frequency domain to remove noise and system natural frequencies. The results from the data indicate that the filter and smoothing technique are successful in identifying the foam crush event and removing aberrations. The effect of strain rate increases with increasing foam density. The 71-WF-HT foam may support Mars Sample Return requirements. Several recommendations to improve the drop tower test technique are identified.

  20. Near-Optimal Re-Entry Trajectories for Reusable Launch Vehicles

    NASA Technical Reports Server (NTRS)

    Chou, H.-C.; Ardema, M. D.; Bowles, J. V.

    1997-01-01

    A near-optimal guidance law for the descent trajectory for earth orbit re-entry of a fully reusable single-stage-to-orbit pure rocket launch vehicle is derived. A methodology is developed to investigate using both bank angle and altitude as control variables and selecting parameters that maximize various performance functions. The method is based on the energy-state model of the aircraft equations of motion. The major task of this paper is to obtain optimal re-entry trajectories under a variety of performance goals: minimum time, minimum surface temperature, minimum heating, and maximum heading change; four classes of trajectories were investigated: no banking, optimal left turn banking, optimal right turn banking, and optimal bank chattering. The cost function is in general a weighted sum of all performance goals. In particular, the trade-off between minimizing heat load into the vehicle and maximizing cross range distance is investigated. The results show that the optimization methodology can be used to derive a wide variety of near-optimal trajectories.

  1. 76 FR 40367 - Federal Acquisition Regulation; Submission for OMB Review; Duty-Free Entry

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-08

    ... Regulation; Submission for OMB Review; Duty- Free Entry AGENCIES: Department of Defense (DOD), General... previously approved information collection requirement concerning duty-free entry. Public comments are... Collection 9000- 0022, Duty-Free Entry by any of the following methods: Regulations.gov :...

  2. Advanced Key Technologies for Hot Control Surfaces in Space Re- Entry Vehicles

    NASA Astrophysics Data System (ADS)

    Dogigli, Michael; Pradier, Alain; Tumino, Giorgio

    2002-01-01

    (1)MAN Technologie AG, D- 86153 Augsburg, Germany (2,3) ESA, 2200 Noordwijk ZH, The Netherlands Current space re-entry vehicles (e.g. X-38 vehicle 201, the prototype of the International Space Station's Crew Return Vehicle (CRV)) require advanced control surfaces (so called body flaps). Such control surfaces allow the design of smaller and lighter vehicles as well as faster re-entries (compared to the US Shuttle). They are designed as light-weight structures that need no metallic parts, need no mass or volume consuming heat sinks to protect critical components (e.g. bearings) and that can be operated at temperatures of more than 1600 "C in air transferring high mechanical loads (dynamic 40 kN, static 70 kN) at the same time. Because there is a need for CRV and also for Reusable Launch Vehicles (RLV) in future, the European Space Agency (ESA) felt compelled to establish a "Future European Space Transportation and Investigation Program,, (FESTIP) and a "General Support for Technology Program,, (GSTP). One of the main goals of these programs was to develop and qualify key-technologies that are able to master the above mentioned challenging requirements for advanced hot control surfaces and that can be applied for different vehicles. In 1996 MAN Technologie has started the development of hot control surfaces for small lifting bodies in the national program "Heiü Strukturen,,. One of the main results of this program was that especially the following CMC (Ceramic Matrix Composite) key technologies need to be brought up to space flight standard: Complex CMC Structures, CMC Bearings, Metal-to-CMC Joining Technologies, CMC Fasteners, Oxidation Protection Systems and Static and Dynamic Seals. MAN Technologie was contracted by ESA to continue the development and qualification of these key technologies in the frame of the FESTIP and the GSTP program. Development and qualification have successfully been carried out. The key technologies have been applied for the X-38 vehicle

  3. Landing Characteristics of a Re-entry Vehicle with a Passive Landing System for Impact Alleviation

    NASA Technical Reports Server (NTRS)

    1963-01-01

    Landing Characteristics of a Re-entry Vehicle with a Passive Landing System for Impact Alleviation. An experimental investigation was made to determine the landing characteristics of a 1/8-scale dynamic model of a reentry vehicle using a passive landing system to alleviate the landing-impact loads. The passive landing system consisted of a flexible heat shield with a small section of aluminum honeycomb placed between the heat shield and the crew compartment at the point that would be the first to contact the landing surface. The model was landed on concrete and sand landing surfaces at parachute letdown velocities. The investigations simulated a vertical velocity of 30 ft/sec (full scale), horizontal velocities of 0, 15, 30, 40, and 50 ft/sec (full scale), and landing attitudes ranging from -30 degrees to 20 degrees. The model investigation indicated that stable landings could be made on a concrete surface at horizontal velocities up to about 30 ft/sec, but the stable landing-attitude range at these speeds was small. The aluminum honeycomb bottomed occasionally during landings on concrete. When bottoming did not occur, maximum normal and longitudinal accelerations at the center of gravity of the vehicle were approximately 50g and 30g, respectively. [Entire movie available on DVD from CASI as Doc ID 20070030981. Contact help@sti.nasa.gov

  4. An Adaptive Numeric Predictor-corrector Guidance Algorithm for Atmospheric Entry Vehicles. M.S. Thesis - MIT, Cambridge

    NASA Technical Reports Server (NTRS)

    Spratlin, Kenneth Milton

    1987-01-01

    An adaptive numeric predictor-corrector guidance is developed for atmospheric entry vehicles which utilize lift to achieve maximum footprint capability. Applicability of the guidance design to vehicles with a wide range of performance capabilities is desired so as to reduce the need for algorithm redesign with each new vehicle. Adaptability is desired to minimize mission-specific analysis and planning. The guidance algorithm motivation and design are presented. Performance is assessed for application of the algorithm to the NASA Entry Research Vehicle (ERV). The dispersions the guidance must be designed to handle are presented. The achievable operational footprint for expected worst-case dispersions is presented. The algorithm performs excellently for the expected dispersions and captures most of the achievable footprint.

  5. Design, Fabrication and Testing of a Crushable Energy Absorber for a Passive Earth Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Kellas, Sotiris; Corliss, James M. (Technical Monitor)

    2002-01-01

    A conceptual study was performed to investigate the impact response of a crushable energy absorber for a passive Earth entry vehicle. The spherical energy-absorbing concept consisted of a foam-filled composite cellular structure capable of omni-directional impact-load attenuation as well as penetration resistance. Five composite cellular samples of hemispherical geometry were fabricated and tested dynamically with impact speeds varying from 30 to 42 meters per second. Theoretical crush load predictions were obtained with the aid of a generalized theory which accounts for the energy dissipated during the folding deformation of the cell-walls. Excellent correlation was obtained between theoretical predictions and experimental tests on characteristic cell-web intersections. Good correlation of theory with experiment was also found to exist for the more complex spherical cellular structures. All preliminary design requirements were met by the cellular structure concept, which exhibited a near-ideal sustained crush-load and approximately 90% crush stroke.

  6. Measurement of lateral launch loads on re-entry vehicles using SWAT

    SciTech Connect

    Mayes, R.L.

    1993-11-01

    The Sum of Weighted Accelerations Technique (SWAT) has been developed at Sandia National Laboratories to infer dynamic forces acting on free elastic structures from acceleration measurements. A derivative of SWAT known as SWAT TEEM (Sum of Weighted Accelerations using Tome Eliminated Elastic Modes) is utilized. This paper describes experiments demonstrating how this technology can be applied to measure lateral launch loads on Re-entry Vehicle (RV) payloads. A technique to determine the number of sensors and best locations is described. Experiments are performed to excite a structure to which a mockup RV is mounted. Acceleration measurements on the RV are used to reconstruct the lateral force acting at the RV base, and these results are compared to measured results.

  7. A Comprehensive Structural Dynamic Analysis Approach for Multi Mission Earth Entry Vehicle (MMEEV) Development

    NASA Technical Reports Server (NTRS)

    Perino, Scott; Bayandor, Javid; Siddens, Aaron

    2012-01-01

    The anticipated NASA Mars Sample Return Mission (MSR) requires a simple and reliable method in which to return collected Martian samples back to earth for scientific analysis. The Multi-Mission Earth Entry Vehicle (MMEEV) is NASA's proposed solution to this MSR requirement. Key aspects of the MMEEV are its reliable and passive operation, energy absorbing foam-composite structure, and modular impact sphere (IS) design. To aid in the development of an EEV design that can be modified for various missions requirements, two fully parametric finite element models were developed. The first model was developed in an explicit finite element code and was designed to evaluate the impact response of the vehicle and payload during the final stage of the vehicle's return to earth. The second model was developed in an explicit code and was designed to evaluate the static and dynamic structural response of the vehicle during launch and reentry. In contrast to most other FE models, built through a Graphical User Interface (GUI) pre-processor, the current model was developed using a coding technique that allows the analyst to quickly change nearly all aspects of the model including: geometric dimensions, material properties, load and boundary conditions, mesh properties, and analysis controls. Using the developed design tool, a full range of proposed designs can quickly be analyzed numerically and thus the design trade space for the EEV can be fully understood. An engineer can then quickly reach the best design for a specific mission and also adapt and optimize the general design for different missions.

  8. Analytical Simulations of Energy-Absorbing Impact Spheres for a Mars Sample Return Earth Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Billings, Marcus Dwight; Fasanella, Edwin L. (Technical Monitor)

    2002-01-01

    Nonlinear dynamic finite element simulations were performed to aid in the design of an energy-absorbing impact sphere for a passive Earth Entry Vehicle (EEV) that is a possible architecture for the Mars Sample Return (MSR) mission. The MSR EEV concept uses an entry capsule and energy-absorbing impact sphere designed to contain and limit the acceleration of collected samples during Earth impact without a parachute. The spherical shaped impact sphere is composed of solid hexagonal and pentagonal foam-filled cells with hybrid composite, graphite-epoxy/Kevlar cell walls. Collected Martian samples will fit inside a smaller spherical sample container at the center of the EEV's cellular structure. Comparisons were made of analytical results obtained using MSC.Dytran with test results obtained from impact tests performed at NASA Langley Research Center for impact velocities from 30 to 40 m/s. Acceleration, velocity, and deformation results compared well with the test results. The correlated finite element model was then used for simulations of various off-nominal impact scenarios. Off-nominal simulations at an impact velocity of 40 m/s included a rotated cellular structure impact onto a flat surface, a cellular structure impact onto an angled surface, and a cellular structure impact onto the corner of a step.

  9. Limit Cycle Analysis Applied to the Oscillations of Decelerating Blunt-Body Entry Vehicles

    NASA Technical Reports Server (NTRS)

    Schoenenberger, Mark; Queen, Eric M.

    2008-01-01

    Many blunt-body entry vehicles have nonlinear dynamic stability characteristics that produce self-limiting oscillations in flight. Several different test techniques can be used to extract dynamic aerodynamic coefficients to predict this oscillatory behavior for planetary entry mission design and analysis. Most of these test techniques impose boundary conditions that alter the oscillatory behavior from that seen in flight. Three sets of test conditions, representing three commonly used test techniques, are presented to highlight these effects. Analytical solutions to the constant-coefficient planar equations-of-motion for each case are developed to show how the same blunt body behaves differently depending on the imposed test conditions. The energy equation is applied to further illustrate the governing dynamics. Then, the mean value theorem is applied to the energy rate equation to find the effective damping for an example blunt body with nonlinear, self-limiting dynamic characteristics. This approach is used to predict constant-energy oscillatory behavior and the equilibrium oscillation amplitudes for the various test conditions. These predictions are verified with planar simulations. The analysis presented provides an overview of dynamic stability test techniques and illustrates the effects of dynamic stability, static aerodynamics and test conditions on observed dynamic motions. It is proposed that these effects may be leveraged to develop new test techniques and refine test matrices in future tests to better define the nonlinear functional forms of blunt body dynamic stability curves.

  10. Structural Analysis and Testing of the Inflatable Re-entry Vehicle Experiment (IRVE)

    NASA Technical Reports Server (NTRS)

    Lindell, Michael C.; Hughes, Stephen J.; Dixon, Megan; Wiley, Cliff E.

    2006-01-01

    The Inflatable Re-entry Vehicle Experiment (IRVE) is a 3.0 meter, 60 degree half-angle sphere cone, inflatable aeroshell experiment designed to demonstrate various aspects of inflatable technology during Earth re-entry. IRVE will be launched on a Terrier-Improved Orion sounding rocket from NASA s Wallops Flight Facility in the fall of 2006 to an altitude of approximately 164 kilometers and re-enter the Earth s atmosphere. The experiment will demonstrate exo-atmospheric inflation, inflatable structure leak performance throughout the flight regime, structural integrity under aerodynamic pressure and associated deceleration loads, thermal protection system performance, and aerodynamic stability. Structural integrity and dynamic response of the inflatable will be monitored with photogrammetric measurements of the leeward side of the aeroshell during flight. Aerodynamic stability and drag performance will be verified with on-board inertial measurements and radar tracking from multiple ground radar stations. In addition to demonstrating inflatable technology, IRVE will help validate structural, aerothermal, and trajectory modeling and analysis techniques for the inflatable aeroshell system. This paper discusses the structural analysis and testing of the IRVE inflatable structure. Equations are presented for calculating fabric loads in sphere cone aeroshells, and finite element results are presented which validate the equations. Fabric material properties and testing are discussed along with aeroshell fabrication techniques. Stiffness and dynamics tests conducted on a small-scale development unit and a full-scale prototype unit are presented along with correlated finite element models to predict the in-flight fundamental mod

  11. Further Investigations of Control Surface Seals for the X-38 Re-Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Dunlap, Patrick H., Jr.; Steinetz, Bruce M.; Curry, Donald M.; Newquist, Charles W.; Verzemnieks, Juris

    2001-01-01

    NASA is currently developing the X-38 vehicle that will be used to demonstrate the technologies required for a potential crew return vehicle (CRV) for the International Space Station. This vehicle would serve both as an ambulance for medical emergencies and as an evacuation vehicle for the Space Station. Control surfaces on the X-38 (body flaps and rudder/fin assemblies) require high temperature seals to limit hot gas ingestion and transfer of heat to underlying low-temperature structures to prevent over-temperature of these structures and possible loss of the vehicle. NASAs Johnson Space Center (JSC) and Glenn Research Center (GRC) are working together to develop and evaluate seals for these control surfaces. This paper presents results for compression. flow, scrub, and arc jet tests conducted on the baseline X-38 rudder/fin seal design. Room temperature seal compression tests were performed at low compression levels to determine load versus linear compression, preload. contact area, stiffness. and resiliency characteristics under low load conditions. For all compression levels that were tested, unit loads and contact pressures for the seals were below the 5 lb/in. and 10 psi limits required to limit the loads on the adjoining Shuttle thermal tiles that the seals will contact. Flow rates through an unloaded (i.e. 0% compression) double arrangement were twice those of a double seal compressed to the 20% design compression level. The seals survived an ambient temperature 1000 cycle scrub test over relatively rough Shuttle tile surfaces. The seals were able to disengage and re-engage the edges of the rub surface tiles while being scrubbed over them. Arc jet tests were performed to experimentally determine anticipated seal temperatures for representative flow boundary conditions (pressures and temperatures) under simulated vehicle re-entry conditions. Installation of a single seat in the gap of the test fixture caused a large temperature drop (1710 F) across the seal

  12. Ceramic Adhesive and Methods for On-Orbit Repair of Re-Entry Vehicles

    NASA Technical Reports Server (NTRS)

    Riedell, James A.; Easler, Timothy E.

    2013-01-01

    This adhesive is capable of repairing damaged leading edge components of reentry vehicles while in space, and is novel with regard to its ability to be applied in the vacuum of space, and in a microgravity environment. Once applied, the adhesive provides thermal and oxidation protection to the substrate (in this case, reinforced carbon/carbon composites, RCCs) during re-entry of a space vehicle. Although there may be many formulations for repair adhesives, at the time of this reporting, this is the first known adhesive capable of an on-orbit repair. The adhesive is an engineered ceramic material composed of a pre-ceramic polymer and refractory powders in the form of a paste or putty that can be applied to a scratched, cracked, or fractured composite surface, covering and protecting the damaged area. The adhesive is then "cured" with a heat cycle, thereby cross-linking the polymer into a hardened material and bonding it to the substrate. During the heat of reentry, the material is converted to a ceramic coating that provides thermal and oxidative stability to the repaired area, thus allowing the vehicle to pass safely from space into the upper atmosphere. Ceramic powders such as SiC, ZrB2 and Y2O3 are combined with allylhydridopolycarbosilane (AHPCS) resin, and are mixed to form a paste adhesive. The material is then applied to the damaged area by brush, spatula, trowel, or other means to fill cracks, gaps, and holes, or used to bond patches onto the damaged area. The material is then cured, in a vacuum, preferably at 250F (approximately equal to 121C) for two hours. The re-entry heating of the vehicle at temperatures in excess of 3,000F (approximately equal to 1,650C) then converts this material into a ceramic coating. This invention has demonstrated advantages in resistance to high temperatures, as was demonstrated in more than 100 arc-jet tests in representative environments at NASA. Extensive testing verified oxidation protection for the repaired substrate (RCC

  13. 76 FR 22707 - Federal Acquisition Regulation; Information Collection; Duty-Free Entry

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-22

    ... Regulation; Information Collection; Duty-Free Entry AGENCIES: Department of Defense (DOD), General Services... approved information collection requirement concerning duty-free entry. Public comments are particularly..., it must notify the contracting officer to determine whether the supplies should be duty-free....

  14. Radiative Heating on the After-Body of Martian Entry Vehicles

    NASA Technical Reports Server (NTRS)

    Brandis, A. M.; Saunders, D. A.; Johnston, C. O.; Cruden, B. A.; White, T. R.

    2015-01-01

    This paper presents simulations of the radiative heat flux imparted on the after-body of vehicles entering the Martian atmosphere. The radiation is dominated by CO2 bands emitting in the mid-wave infrared spectral region. This mechanism has traditionally not been considered in the design of past Mars entry vehicles. However, with recent analysis showing that the CO2 radiation can be greater than convective heating in the wake, and with several upcoming and proposed missions to Mars potentially affected, an investigation of the impact of this radiation is warranted. The focus of this paper is to provide a better understanding of the impact to aerothermal heating predictions and to provide comparisons between NASA's two main radiation codes, NEQAIR and HARA. The tangent slab approximation is shown to be overly conservative, by as much as 58 percent, for most back- shell body point locations compared to using a full angular integration method. However, due to the complexity of the wake flow, it is also shown that tangent slab does not always represent an upper limit for radiative heating. Furthermore, analysis in this paper shows that it is not possible to provide a general knock-down factor from the tangent slab results to those obtained using the more rigorous full integration method. When the radiative heating is accounted for on the after-body, the unmargined total heat flux can be as high as 14 watts per square centimeter.

  15. Data Acquisition System for Electric Vehicle's Driving Motor Test Bench Based on VC++

    NASA Astrophysics Data System (ADS)

    Qiang, Song; Chenguang, Lv

    In order to solve such problems as great labor intensity, high cost, low efficiency and accuracy during the performance experiment for driving motor system of electric vehicles, and realize data acquisition automatically and synchronously, a data acquisition system for driving motor test bench based on visual instruments is designed. This data acquisition system can be used to obtain the driving motor's parameters of currents and voltages at the same time. This system's hardware is based on electric vehicle's motor test bench in Beijing Institute of Technology, and combined with PXI2010 data acquisition card from ADLINK Company. Visual c++ software is adopted as development tool. In this paper, the design and realization of the hardware and software are presented. Experiment results show that this system improves the efficiency and quality of testing task with high utility. And experiment data can be obtained accurately.

  16. Turbulent Aeroheating Testing of Mars Science Laboratory Entry Vehicle in Perfect-Gas Nitrogen

    NASA Technical Reports Server (NTRS)

    Hollis, Brian R.; Collier, Arnold S.

    2007-01-01

    An experimental investigation of turbulent aeroheating on the Mars Science Laboratory entry vehicle heat shield has been conducted in the Arnold Engineering Development Center Hypervelocity Wind Tunnel No. 9. Testing was performed on a 6-in. (0.1524 m) diameter MSL model in pure N2 gas in the tunnel s Mach 8 and Mach 10 nozzles at free stream Reynolds numbers of 4.1x10(exp 6)/ft to 49x10(exp 6)/ft (1.3x10(exp 7)/m to 16x10(exp 7)/m) and 1.2x10(exp 6)/ft to 19x10(exp 6)/ft (0.39x10(exp 7)/m to 62x10(exp 7)/m), respectively. These conditions were sufficient to span the regime of boundary-layer flow from completely laminar to fully-developed turbulent flow over the entire forebody. A supporting aeroheating test was also conducted in the Langley Research Center 20-Inch Mach 6 Air Tunnel at free stream Reynolds number of 1x10(exp 6)/ft to 7x10(exp 6)/ft (0.36x10(exp 7)/m to 2.2x10(exp 7)/m) in order to help corroborate the Tunnel 9 results. A complementary computational fluid dynamics study was conducted in parallel to the wind tunnel testing. Laminar and turbulent predictions were generated for all wind tunnel test conditions and comparisons were performed with the data for the purpose of helping to define uncertainty margins on predictions for aeroheating environments during entry into the Martian atmosphere. Data from both wind tunnel tests and comparisons with the predictions are presented herein. It was concluded from these comparisons that for perfect-gas conditions, the computational tools could predict fully-laminar or fully-turbulent heating conditions to within 10% of the experimental data

  17. The Development of a Nonequilibrium Radiative Heat Transfer Computational Model for High Altitude Entry Vehicle Flowfield Methods

    NASA Technical Reports Server (NTRS)

    Carlson, Leland A.

    1995-01-01

    This final report will attempt to concisely summarize the activities and accomplishments associated with NASA Grant and to include pertinent documents in an appendix. The project initially had one primary and several secondary objectives. The original primary objective was to couple into the NASA Johnson Space Center (JSC) nonequilibrium chemistry Euler equation entry vehicle flowfield code, INEQ3D, the Texas A&M University (TAMU) local thermodynamic nonequilibrium (LTNE) radiation model. This model had previously been developed and verified under NASA Langley and NASA Johnson sponsorship as part of a viscous shock layer entry vehicle flowfield code. The secondary objectives were: (1) to investigate the necessity of including the radiative flux term in the vibrational-electron-electronic (VEE) energy equation as well as in the global energy equation, (2) to determine the importance of including the small net change in electronic energy between products and reactants which occurs during a chemical reaction, and (3) to study the effect of atom-atom impact ionization reactions on entry vehicle nonequilibrium flowfield chemistry and radiation. For each, of these objectives, it was assumed that the code would be applicable to lunar return entry conditions, i.e. altitude above 75 km, velocity greater, than 11 km/sec, where nonequilibrium chemistry and radiative heating phenomena would be significant. In addition, it was tacitly assumed that as part of the project the code would be applied to a variety of flight conditions and geometries.

  18. On Board Data Acquisition System with Intelligent Transducers for Unmanned Aerial Vehicles

    NASA Astrophysics Data System (ADS)

    Rochala, Zdzisław

    2012-02-01

    This report presents conclusions from research project no. ON50900363 conducted at the Mechatronics Department, Military University of Technology in the years 2007-2010. As the main object of the study involved the preparation of a concept and the implementation of an avionics data acquisition system intended for research during flight of unmanned aerial vehicles of the mini class, this article presents a design of an avionics system and describes equipment solutions of a distributed measurement system intended for data acquisition consisting of intelligent transducers. The data collected during a flight controlled by an operator confirmed proper operation of the individual components of the data acquisition system.

  19. FLPP IXV Re-entry Vehicle, Transonic Characterisation Based on FOI T1500 Wind Tunnel Tests and CFD

    NASA Astrophysics Data System (ADS)

    Torngren, L.; Chiarelli, C.; Mareschi, V.; Tribot, J.-P.; Binetti, P.; Walloschek, T.

    2009-01-01

    The European Space Agency ESA, has engaged in 2004, the IXV project (Intermediate eXperimental Vehicle) which is part of the FLPP (Future Launcher Preparatory Programme) aiming at answering to critical technological issues, while supporting the future generation launchers and to improve in general European capabilities in the strategic field of atmospheric re-entry for space transportation, exploration and scientific applications. The IXV key mission and system objectives are the design, development, manufacturing, assembling and on-ground to in-flight verification of an autonomous European lifting and aerodynamically controlled re-entry system, integrating the critical re-entry technologies at the system level. The current IXV vehicle is a slender body type exhibiting rounded shape, thick body controlled by means of two control surfaces. The current mission is to perform an atmospheric re- entry ended by a safe recovery in supersonic regime. A potential extension of the flight domain down to the transonic regime was proposed to be analyzed. The objectives were to study the capability of the IXV for flying autonomously enabling a recovery of the vehicle by means of a subsonic parachute based DRS. The vehicle designed for the hypersonic speeds integrating a large base with only two control surfaces located close to the plane of symmetry is definitively not tuned for transonic ones. CFD done by Thales Alenia Space and wind tunnel activities involving FOI T1500 facility contributed to built up an Aerodynamic Data Base (AEDB) to be used as inputs for flying qualities analysis and re-entry simulations. The paper presents the main objectives of the transonic activities with emphasis on CFD and WTT including a description of the different prediction tools and discussing the main outcomes of the current data comparisons.

  20. 41 CFR 102-34.70 - What do we do with completed calculations of our fleet vehicle acquisitions?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What do we do with completed calculations of our fleet vehicle acquisitions? 102-34.70 Section 102-34.70 Public Contracts and... What do we do with completed calculations of our fleet vehicle acquisitions? You must maintain...

  1. Blended skip entry guidance for low-lifting lunar return vehicles

    NASA Astrophysics Data System (ADS)

    Luo, Zong-Fu; Zhang, Hong-Bo; Tang, Guo-Jian

    2014-12-01

    A skip entry guidance algorithm blending numerical predictor-corrector and nominal trajectory tracking is presented for lunar return vehicles. The guidance is decoupled into longitudinal and lateral channels. A piecewise bank-vs-energy magnitude profile and a sign profile are adopted in the skip phase. A magnitude parameter is used to adjust the predicted downrange, and a pseudo-crossrange at the beginning of the final phase is selected as the lateral control variable. Prediction biases of both channels are nullified by a false position iteration algorithm. An on-line estimation and modeling method is introduced to compensate for aerodynamic and atmospheric uncertainties. A nominal trajectory for the final phase is generated based on actual reenter conditions, and the obtained nominal trajectory is tracked by a linear feedback law. A lateral corridor is used to manage the lateral state. The proposed guidance algorithm is assessed using three-degree-of-freedom Monte Carlo analyses, and the results show a satisfactory and robust performance under highly stressful dispersions.

  2. A Flight Study of a Power-Off Landing Technique Applicable to Re-Entry Vehicles

    NASA Technical Reports Server (NTRS)

    Bray, Richard S.; Drinkwater, Fred J.; White, Maurice D.

    1960-01-01

    A power-off landing technique, applicable to aircraft of configurations presently being considered for manned re-entry vehicles, has been developed and flight tested at Ames Research Center. The flight tests used two configurations of an airplane for which the values of maximum lift-drag ratios were 4.0 and 2.8. Twenty-four idle-power approaches were made to an 8000-foot runway with touchdown point and airspeed accuracies of +/-600 feet and +/-10 knots, respectively. The landing pattern used was designed to provide an explicitly defined flight path for the pilot and, yet, to require no external guidance other than the pilot's view from the cockpit. The initial phase of the approach pattern is a constant high-speed descent from altitude aimed at a ground reference point short of the runway threshold. At a specified altitude and speed, a constant g pull-out is made to a shallow flight path along which the air-plane decelerates to the touchdown point. Repeatability and safety are inherent because of the reduced number of variables requiring pilot judgment, and because of the fact that a missed approach is evident at speeds and altitudes suitable for safe ejection. The accuracy and repeatability of the pattern are indicated by the measured results. The proposed pattern appears to be particularly suitable for configurations having unusual drag variations with speed in the lower speed regime, since the pilot is not required to control speed in the latter portions of the pattern.

  3. Impact Test and Simulation of Energy Absorbing Concepts for Earth Entry Vehicles

    NASA Technical Reports Server (NTRS)

    Billings, Marcus D.; Fasanella, Edwin L.; Kellas, Sotiris

    2001-01-01

    Nonlinear dynamic finite element simulations have been performed to aid in the design of an energy absorbing concept for a highly reliable passive Earth Entry Vehicle (EEV) that will directly impact the Earth without a parachute. EEV's are designed to return materials from asteroids, comets, or planets for laboratory analysis on Earth. The EEV concept uses an energy absorbing cellular structure designed to contain and limit the acceleration of space exploration samples during Earth impact. The spherical shaped cellular structure is composed of solid hexagonal and pentagonal foam-filled cells with hybrid graphite- epoxy/Kevlar cell walls. Space samples fit inside a smaller sphere at the center of the EEV's cellular structure. Comparisons of analytical predictions using MSC,Dytran with test results obtained from impact tests performed at NASA Langley Research Center were made for three impact velocities ranging from 32 to 40 m/s. Acceleration and deformation results compared well with the test results. These finite element models will be useful for parametric studies of off-nominal impact conditions.

  4. Dynamic Stability Analysis of Blunt Body Entry Vehicles Using Time-Lagged Aftbody Pitching Moments

    NASA Technical Reports Server (NTRS)

    Kazemba, Cole D.; Braun, Robert D.; Schoenenberger, Mark; Clark, Ian G.

    2013-01-01

    This analysis defines an analytic model for the pitching motion of blunt bodies during atmospheric entry. The proposed model is independent of the pitch damping sum coefficient present in the standard formulation of the equations of motion describing pitch oscillations of a decelerating blunt body, instead using the principle of a time-lagged aftbody moment as the forcing function for oscillation divergence. Four parameters, all with intuitive physical relevance, are introduced to fully define the aftbody moment and the associated time delay. It is shown that the dynamic oscillation responses typical to blunt bodies can be produced using hysteresis of the aftbody moment in place of the pitch damping coefficient. The approach used in this investigation is shown to be useful in understanding the governing physical mechanisms for blunt body dynamic stability and in guiding vehicle and mission design requirements. A validation case study using simulated ballistic range test data is conducted. From this, parameter identification is carried out through the use of a least squares optimizing routine. Results show good agreement with the limited existing literature for the parameters identified, suggesting that the model proposed could be validated by an experimental ballistic range test series. The trajectories produced by the identified parameters were found to match closely those from the MER ballistic range tests for a wide array of initial conditions and can be identified with a reasonable number of ballistic range shots and computational effort.

  5. Correlations for Boundary-Layer Transition on Mars Science Laboratory Entry Vehicle Due to Heat-Shield Cavities

    NASA Technical Reports Server (NTRS)

    Hollis, Brian R.; Liechty, Derek S.

    2008-01-01

    The influence of cavities (for attachment bolts) on the heat-shield of the proposed Mars Science Laboratory entry vehicle has been investigated experimentally and computationally in order to develop a criterion for assessing whether the boundary layer becomes turbulent downstream of the cavity. Wind tunnel tests were conducted on the 70-deg sphere-cone vehicle geometry with various cavity sizes and locations in order to assess their influence on convective heating and boundary layer transition. Heat-transfer coefficients and boundary-layer states (laminar, transitional, or turbulent) were determined using global phosphor thermography.

  6. 41 CFR 102-34.80 - Where may we obtain help with our motor vehicle acquisition plans?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... PROPERTY 34-MOTOR VEHICLE MANAGEMENT Obtaining Fuel Efficient Motor Vehicles § 102-34.80 Where may we... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false Where may we obtain help with our motor vehicle acquisition plans? 102-34.80 Section 102-34.80 Public Contracts and...

  7. Experimental Measurement of RCS Jet Interaction Effects on a Capsule Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Buck, Gregory M.; Watkins, A. Neal; Danehy, Paul M.; Inman, Jennifer A.; Alderfer, David W.; Dyakonov, Artem A.

    2008-01-01

    An investigation was made in NASA Langley Research Center s 31-Inch Mach 10 Tunnel to determine the effects of reaction-control system (RCS) jet interactions on the aft-body of a capsule entry vehicle. The test focused on demonstrating and improving advanced measurement techniques that would aid in the rapid measurement and visualization of jet interaction effects for the Orion Crew Exploration Vehicle while providing data useful for developing engineering models or validation of computational tools used to assess actual flight environments. Measurements included global surface imaging with pressure and temperature sensitive paints and three-dimensional flow visualization with a scanning planar laser induced fluorescence technique. The wind tunnel model was fabricated with interchangeable parts for two different aft-body configurations. The first, an Apollo-like configuration, was used to focus primarily on the forward facing roll and yaw jet interactions which are known to have significant aft-body heating augmentation. The second, an early Orion Crew Module configuration (4-cluster jets), was tested blowing only out of the most windward yaw jet, which was expected to have the maximum heating augmentation for that configuration. Jet chamber pressures and tunnel flow conditions were chosen to approximate early Apollo wind tunnel test conditions. Maximum heating augmentation values measured for the Apollo-like configuration (>10 for forward facing roll jet and 4 for yaw jet) using temperature sensitive paint were shown to be similar to earlier experimental results (Jones and Hunt, 1965) using a phase change paint technique, but were acquired with much higher surface resolution. Heating results for the windward yaw jet on the Orion configuration had similar augmentation levels, but affected much less surface area. Numerical modeling for the Apollo-like yaw jet configuration with laminar flow and uniform jet outflow conditions showed similar heating patterns

  8. Thermal protection of re-entry vehicles with the usage of inflatable systems

    NASA Astrophysics Data System (ADS)

    Alifanov, O. M.; Outchvatov, V. I.; Pichkhadze, K. M.

    2003-08-01

    The Report comprises the results of theoretical and experimental research aimed at development of special devices intended to increase the effectiveness of spacecraft (SC) descent-systems onto the surface of planets with atmosphere. The subject of research is the thermal protection of a SC. Inflatable braking devices (IBD) made of elastic materials and substantially reducing the value SC's ballistic parameter are considered as special devices. Parametric evaluations of influence of descent SC's ballistic coefficient on specific convective heat fluxes at the zone critical point [ qc = A1·(σ) 1/2] were the basis of experimental research. A 1 coefficient is a function of a number of parameters (given descent vehicle (DV) configuration, atmospheric parameters, angle of entry, and empirical estimations of experiments). Analysis and experiments have shown that real materials permit to develop inflatable devices, geometrical and mass properties of which allow reducing a value of σ by 2 … 2.5 times in comparison with the existing ones. This leads to a reduction of thermal fluxes by 10 … 15 times. At such an intensity of external convective heat fluxes, the most effective thermal protection of a DV turns out to be a protection composed by means of a so-called "heat shields method". Their emanation provides an equilibrium state of the system. Parametric dependency of shield surface temperature at a critical point is defined as: T K = A2·( q c) 1/8 In accordance with the results of expert estimations, the Report describes the dependency of ballistic coefficients values of DV vs. payload (PL) masses regarding producible modern materials. In the framework of projects fulfilled on the basis of current research, elastic thermal protection was developed in order to protect a critical point zone of DV. The Report gives a comparison of possible mass properties of IBD-based DV with analogous parameters of real DV carrying out ballistic trajectory descent.

  9. Exterior, looking west Beale Air Force Base, Perimeter Acquisition ...

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

    Exterior, looking west - Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Civil Engineering Storage Building, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  10. Interior, looking northwest Beale Air Force Base, Perimeter Acquisition ...

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

    Interior, looking northwest - Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Civil Engineering Storage Building, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  11. Interior, looking northeast Beale Air Force Base, Perimeter Acquisition ...

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

    Interior, looking northeast - Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Microwave Equipment Building, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  12. Orbital and entry tracking accessory for globes. [to provide range requirements for reentry vehicles to any landing site

    NASA Technical Reports Server (NTRS)

    Pritchard, E. B. (Inventor)

    1974-01-01

    An orbital and entry tracking accessory or attachment is described which can be mounted on a globe to provide a rapid means of determining range requirements for entry vehicles returning from any orbit to any desired landing site with reasonable accuracy. The device is constructed of clear plastic strip material, and comprises a support ring, a calibrated orbital track member rigidly carried by the support ring, and a calibrated lateral range member pivotally coupled to the support ring at points such that the lateral range member is always oriented normally to the orbital track member. The assembly is mountable on the globe relatively snugly, but freely movable. At least one of the members has a detachable coupling which permits placement of the device on the globe.

  13. The use of virtual reality and physical tools in the development and validation of ease of entry and exit in passenger vehicles.

    PubMed

    Lawson, Glyn; Herriotts, Paul; Malcolm, Louise; Gabrecht, Katharina; Hermawati, Setia

    2015-05-01

    Ease of entry and exit is important for creating a positive first impression of a car and increasing customer satisfaction. Several methods are used within vehicle development to optimise ease of entry and exit, including CAD reviews, benchmarking and buck trials. However, there is an industry trend towards digital methods to reduce the costs and time associated with developing physical prototypes. This paper reports on a study of entry strategy in three properties (buck, car, CAVE) in which inconsistencies were demonstrated by people entering a vehicle representation in the CAVE. In a second study industry practitioners rated the CAVE as worse than physical methods for identifying entry and exit issues, and having lower perceived validity and reliability. However, the resource issues associated with building bucks were recognised. Recommendations are made for developing the CAVE and for combinations of methods for use at different stages of a vehicle's development. PMID:25683551

  14. High-Temperature Properties of Ceramic Fibers and Insulations for Thermal Protection of Atmospheric Entry and Hypersonic Cruise Vehicles

    NASA Technical Reports Server (NTRS)

    Kourtides, Demetrius A.; Pitts, William C.; Araujo, Myrian; Zimmerman, R. S.

    1988-01-01

    Multilayer insulations which will operate in the 500C to 1000C temperature range are being considered for possible applications on aerospace vehicles subject to convective and radiative heating during atmospheric entry. The insulations described in this paper consist of ceramic fabrics, insulations, and metal foils quilted together using ceramic thread. As these types of insulations have highly anisotropic properties, the total heat transfer characteristics of these insulations must be determined. Data are presented on the thermal diffusivity and thermal conductivity of four types of multilayer insulations and are compared to the baseline Advanced Flexible Reusable Surface Insulation

  15. 41 CFR 102-34.80 - Where may we obtain help with our motor vehicle acquisition plans?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Where may we obtain help with our motor vehicle acquisition plans? 102-34.80 Section 102-34.80 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 34-MOTOR VEHICLE...

  16. Visualization of Flowfield Modification by RCS Jets on a Capsule Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Danehy, P. M.; Inman, J. A.; Alderfer, D. W.; Buck, G. M.; Schwartz, R.

    2008-01-01

    Nitric oxide planar laser-induced fluorescence (NO PLIF) has been used to visualize the flow on the aft-body of an entry capsule having an activated RCS jet in NASA Langley Research Center's 31-Inch Mach 10 wind tunnel facility. A capsule shape representative of the Apollo command module was tested. These tests were performed to demonstrate the ability of the PLIF method to visualize RCS jet flow while providing some preliminary input to NASA's Orion Vehicle design team. Two different RCS nozzle designs - conical and contoured - were tested. The conical and contoured nozzles had area ratios of 13.4 and 22.5 respectively. The conical nozzle had a half-angle of 10 . Low- and high-Reynolds number cases were investigated by changing the tunnel stagnation pressure from 350 psi to 1300 psi, resulting in freestream Reynolds numbers of 0.56 and 1.8 million per foot respectively. For both of these cases, three different jet plenum pressures were tested (nominally 56, 250 and 500 psi). A single angle-of-attack was investigated (24 degrees). NO PLIF uses an ultraviolet laser sheet to interrogate a slice in the flow containing seeded NO; this UV light excites fluorescence from the NO molecules which is detected by a high-speed digital camera. The system has spatial resolution of about 200 microns (2 pixel blurring) and has flow-stopping time resolution (approximately 1 microsecond). NO was seeded into the flow two different ways. First, the RCS jet fluid was seeded with approximately 1-5% NO, with the balance N2. This allowed observation of the shape, structure and trajectory of the RCS jets. Visualizations of both laminar and turbulent flow jet features were obtained. Visualizations were obtained with the tunnel operating at Mach 10 and also with the test section held at a constant pressure similar to the aftbody static pressure (0.04 psi) obtained during tunnel runs. These two conditions are called "tunnel on" and "tunnel off" respectively. Second, the forebody flow was

  17. Vehicle unpaved road response spectrum acquisition based on accelerometer and GPS data.

    PubMed

    Cong, Nan; Shang, Jianzhong; Ren, Yanxi; Guo, Yao

    2012-01-01

    This paper describes a response acquisition system composed of some spindle accelerometers and a time synchronized on-board GPS receiver developed in order to collect the dynamic response of vehicle riding on an unpaved road. A method of time-space conversion for calculating the response spectrum is proposed to eliminate the adverse effect of time-varying speed, based on the transform from the equitime sampled spindle acceleration responses to equidistance sampling. By using two groups of independent distance histories acquired from GPS, a method called long-range error correction is proposed to improve the accuracy of the vehicle's distance information, which is critical for the time-space conversion. The accuracy and limitations of the system have been analyzed, and its validity has been verified by implementing the system on a wheel loader for road response spectrum measuring. This paper offers a practical approach to obtaining unpaved road response spectra for durability road simulation. PMID:23112581

  18. Protecting Astronaut Health at First Entry into Vehicles Visiting the international Space Station: Insights from Whole-Module Offgas Testing

    NASA Technical Reports Server (NTRS)

    Meyers, Valerie

    2014-01-01

    NASA has accumulated considerable experience in offgas testing of whole modules prior to their docking with the International Space Station (ISS). Since 1998, the Space Toxicology Office has performed offgas testing of the Lab module, both MPLM modules, US Airlock, Node 1, Node 2, Node 3, ATV1, HTV1, and three commercial vehicles. The goal of these tests is twofold: first, to protect the crew from adverse health effects of accumulated volatile pollutants when they first enter the module on orbit, and secondly, to determine the additional pollutant load that the ISS air revitalization systems must handle. In order to predict the amount of accumulated pollutants, the module is sealed for at least 1/5th the worst-case time interval that could occur between the last clean air purge and final hatch closure on the ground and the crew's first entry on orbit. This time can range from a few days to a few months. Typically, triplicate samples are taken at pre-planned times throughout the test. Samples are then analyzed by gas chromatography and mass spectrometry, and the rate of accumulation of pollutants is then extrapolated over time. The analytical values are indexed against 7-day spacecraft maximum allowable concentrations (SMACs) to provide a prediction of the total toxicity value (T-value) at the time of first entry. This T-value and the toxicological effects of specific pollutants that contribute most to the overall toxicity are then used to guide first entry operations. Finally, results are compared to first entry samples collected on orbit to determine the predictive ability of the ground-based offgas test.

  19. Solar power satellite system definition study. Part 2, volume 8: SPS launch vehicle ascent and entry sonic overpressure and noise effects

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Recoverable launch vehicle concepts for the Solar Power Satellite program were identified. These large launch vehicles are powered by proposed engines in the F-1 thrust level class. A description of the candidate launch vehicles and their operating mode was provided. Predictions of the sonic over pressures during ascent and entry for both types of vehicles, and prediction of launch noise levels in the vicinity of the launch site were included. An overall assessment and criteria for sonic overpressure and noise levels was examined.

  20. Data Acquisition (DAQ) system dedicated for remote sensing applications on Unmanned Aerial Vehicles (UAV)

    NASA Astrophysics Data System (ADS)

    Keleshis, C.; Ioannou, S.; Vrekoussis, M.; Levin, Z.; Lange, M. A.

    2014-08-01

    Continuous advances in unmanned aerial vehicles (UAV) and the increased complexity of their applications raise the demand for improved data acquisition systems (DAQ). These improvements may comprise low power consumption, low volume and weight, robustness, modularity and capability to interface with various sensors and peripherals while maintaining the high sampling rates and processing speeds. Such a system has been designed and developed and is currently integrated on the Autonomous Flying Platforms for Atmospheric and Earth Surface Observations (APAESO/NEA-YΠOΔOMH/NEKΠ/0308/09) however, it can be easily adapted to any UAV or any other mobile vehicle. The system consists of a single-board computer with a dual-core processor, rugged surface-mount memory and storage device, analog and digital input-output ports and many other peripherals that enhance its connectivity with various sensors, imagers and on-board devices. The system is powered by a high efficiency power supply board. Additional boards such as frame-grabbers, differential global positioning system (DGPS) satellite receivers, general packet radio service (3G-4G-GPRS) modems for communication redundancy have been interfaced to the core system and are used whenever there is a mission need. The onboard DAQ system can be preprogrammed for automatic data acquisition or it can be remotely operated during the flight from the ground control station (GCS) using a graphical user interface (GUI) which has been developed and will also be presented in this paper. The unique design of the GUI and the DAQ system enables the synchronized acquisition of a variety of scientific and UAV flight data in a single core location. The new DAQ system and the GUI have been successfully utilized in several scientific UAV missions. In conclusion, the novel DAQ system provides the UAV and the remote-sensing community with a new tool capable of reliably acquiring, processing, storing and transmitting data from any sensor integrated

  1. Inverse Temperature Mapping of Re-Entry Vehicle Control Surfaces Using Infrared Thermography

    NASA Astrophysics Data System (ADS)

    Pereira, C.; Hirtz, B.; Vuilleumier, A.; Roesgen, T.; Vos, J.

    2009-01-01

    This paper summarizes the development of an optical system to deliver rear face temperatures thermal maps of an EXPERT vehicle flap using near infrared thermography. The optical system consists of a wide angle lens assembly placed behind the flap, a fiber optic cable and a high rate near infrared camera. The camera transfers images to an autonomous data handling unit located on a colder area of the vehicle. After flight the temperature on the flap windward face is computed using the stored thermal maps as input to a coupled fluid dynamics-heat transfer calculation. The system has been successfully qualified for the EXPERT mission and the inverse temperature reconstruction will be tested in the Scirocco Plasma Wind tunnel. A further evolution of this system allowing simultaneous measurement of temperature and emissivity is planned for the IXV vehicle

  2. CARINA - A space vehicle with re-entry capabilities for microgravity experiments

    NASA Astrophysics Data System (ADS)

    Borriello, G.; Sansone, A.; Ricciardi, A.

    1992-08-01

    An Italian autonomous space vehicle with recovery capabilities, named CARINA (Capsula di Rientro Non Abitata), is described with special attention given to the technological developments in areas pertaining to the reentry system, including reentry aerothermodynamics and the design of the thermal protection system. Consideration is also given to the configuration of the CARINA vehicle (comprised of the expendable Service Module and the Apollo-like Reentry Module), the subsystems and their performances, the mission life cycle, the microgravity utilization aspects, and the programmatic aspects.

  3. High-temperature properties of ceramic fibers and insulations for thermal protection of atmospheric entry and hypersonic cruise vehicles

    NASA Technical Reports Server (NTRS)

    Kourtides, Demetrius A.; Pitts, William C.; Araujo, Myrian; Zimmerman, R. S.

    1988-01-01

    Multilayer insulations (MIs) which will operate in the 500 to 1000 C temperature range are being considered for possible applications on aerospace vehicles subject to convective and radiative heating during atmospheric entry. The insulations described consist of ceramic fibers, insulations, and metal foils quilted together with ceramic thread. As these types of insulations have highly anisotropic properties, the total heat transfer characteristics must be determined. Data are presented on the thermal diffusivity and thermal conductivity of four types of MIs and are compared to the baseline Advanced Flexible Reusable Surface Insulation currently used on the Space Shuttle Orbiter. In addition, the high temperature properties of the fibers used in these MIs are discussed. The fibers investigated included silica and three types of aluminoborosilicate (ABS). Static tension tests were performed at temperatures up to 1200 C and the ultimate strain, tensile strength, and tensile modulus of single fibers were determined.

  4. High temperature properties of ceramic fibers and insulations for thermal protection of atmospheric entry and hypersonic cruise vehicles

    NASA Technical Reports Server (NTRS)

    Kourtides, Demetrius A.; Pitts, William C.; Araujo, Myrian; Zimmerman, R. S.

    1988-01-01

    Multilayer insulations (MIs) which will operate in the 500 to 1000 C temperature range are being considered for possible applications on aerospace vehicles subject to convective and radiative heating during atmospheric entry. The insulations described consist of ceramic fibers, insulations, and metal foils quilted together with ceramic thread. As these types of insulations have highly anisotropic properties, the total heat transfer characteristics must be determined. Data are presented on the thermal diffusivity and thermal conductivity of four types of MIs and are compared to the baseline Advanced Flexible Reusable Surface Insulation currently used on the Space Shuttle Orbiter. In addition, the high temperature properties of the fibers used in these MIs are discussed. The fibers investigated included silica and three types of aluminoborosilicate (ABS). Static tension tests were performed at temperatures up to 1200 C and the ultimate strain, tensile strength, and tensile modulus of single fibers were determined.

  5. High-temperature properties of ceramic fibers and insulations for thermal protection of atmospheric entry and hypersonic cruise vehicles

    SciTech Connect

    Kourtides, D.A.; Pitts, W.C.; Araujo, M.; Zimmerman, R.S.

    1988-02-01

    Multilayer insulations (MIs) which will operate in the 500 to 1000 C temperature range are being considered for possible applications on aerospace vehicles subject to convective and radiative heating during atmospheric entry. The insulations described consist of ceramic fibers, insulations, and metal foils quilted together with ceramic thread. As these types of insulations have highly anisotropic properties, the total heat transfer characteristics must be determined. Data are presented on the thermal diffusivity and thermal conductivity of four types of MIs and are compared to the baseline Advanced Flexible Reusable Surface Insulation currently used on the Space Shuttle Orbiter. In addition, the high temperature properties of the fibers used in these MIs are discussed. The fibers investigated included silica and three types of aluminoborosilicate (ABS). Static tension tests were performed at temperatures up to 1200 C and the ultimate strain, tensile strength, and tensile modulus of single fibers were determined.

  6. Heat transfer and pressure distributions at M equals 8 on 0.029 scale models of the Viking entry vehicle

    NASA Technical Reports Server (NTRS)

    Faye-Petersen, R.; Sarver, D.; Carroll, H.

    1972-01-01

    An investigation in the Langley Research Center Mach-8 Variable Density Hypersonic Tunnel was made of the pressure distributions and heat transfer rate distributions on two 0.029 scale Viking Entry Vehicle models. Comparable ranges of test Reynolds number were exercised for the two tests between run conditions around 4 million and conditions of about 1.6 million. At angles of attack less than 20 degrees the pressure ratio distribution referenced to stagnation pressure appeared invariant with Reynolds number. Increasing angle of attack results in a flatter distribution of both the windward and leeward pressure distributions; in addition, the stagnation point shifted into the windward plane. A subsequent rise in the heating rate profile on the leeward side with further increase in angle of attack is attributed to boundary layer natural transition to turbulent flow. Schlieren photographs were taken for flow field visualization and to correct model angle of attack.

  7. Simulation study of communication link for Pioneer Saturn/Uranus atmospheric entry probe. [signal acquisition by candidate modem for radio link

    NASA Technical Reports Server (NTRS)

    Hinrichs, C. A.

    1974-01-01

    A digital simulation is presented for a candidate modem in a modeled atmospheric scintillation environment with Doppler, Doppler rate, and signal attenuation typical of the radio link conditions for an outer planets atmospheric entry probe. The results indicate that the signal acquisition characteristics and the channel error rate are acceptable for the system requirements of the radio link. The simulation also outputs data for calculating other error statistics and a quantized symbol stream from which error correction decoding can be analyzed.

  8. Guidance and control analysis of the entry of a lifting body personnel launch vehicle

    NASA Technical Reports Server (NTRS)

    Powell, Richard W.; Cruz, Christopher I.

    1991-01-01

    NASA is currently involved in definition studies of a Personnel Launch System (PLS) that could be used to transport people to and from low-earth orbit. This vehicle would serve both to complement the Space Shuttle and to provide alternative access to space in the event the Space Shuttle fleet were unavailable for a prolonged period. The PLS would consist of a manned spacecraft launched by an expendable vehicle, e.g., Titan 4. One promising candidate for the manned component of the PLS is the NASA Langley Research Center HL-20 lifting body. Many studies are currently underway to assess this vehicle, and one of the main areas of study is the development of the capability to successfully enter, glide to the landing site, and land. To provide this capability, guidance and control algorithms have been developed, incorporated into a six-degree-of-freedom simulation, and evaluation in the presence of off-nominal atmospheric conditions, consisting of both density variations and steady-state winds. In addition, the impact of atmospheric turbulence was examined for the portion of flight from Mach 3.5 to touchdown. This analysis showed that the vehicle remained controllable and could successfully land even in the presence of off-nominal atmospheric conditions.

  9. Influence of Coupled Radiation and Ablation on the Aerothermodynamic Environment of Planetary Entry Vehicles

    NASA Technical Reports Server (NTRS)

    Johnston, Christopher O.; Gnoffo, Peter A.; Mazaheri, Alireza

    2013-01-01

    A review of recently published coupled radiation and ablation capabilities involving the simulation of hypersonic flowfields relevant to Earth, Mars, or Venus entry is presented. The three fundamental mechanisms of radiation coupling are identified as radiative cooling, precursor photochemistry, and ablation-radiation interaction. The impact of these mechanisms are shown to be significant for a 3 m radius sphere entering Earth at hypothetical Mars return conditions (approximately 15 km/s). To estimate the influence precursor absorption on the radiative flux for a wide range of conditions, a simplified approach is developed that requires only the non-precursor solution. Details of a developed coupled ablation approach, which is capable of treating both massively ablating flowfields in the sublimation regime and weakly ablating diffusion Climited oxidation cases, are presented. A review of the two primary uncoupled ablation approximations, identified as the blowing correction and film coefficient approximations, is made and their impact for Earth and Mars entries is shown to be significant for recession and convective heating predictions. Fully coupled ablation and radiation simulations are presented for the Mars return sphere throughout its entire trajectory. Applying to the Mars return sphere the Pioneer- Venus heritage carbon phenolic heatshield, which has properties available in the open literature, the differences between steady state ablation and coupling to a material response code are shown to be significant.

  10. Entry vehicle performance analysis and atmospheric guidance algorithm for precision landing on Mars. M.S. Thesis - Massachusetts Inst. of Technology

    NASA Technical Reports Server (NTRS)

    Dieriam, Todd A.

    1990-01-01

    Future missions to Mars may require pin-point landing precision, possibly on the order of tens of meters. The ability to reach a target while meeting a dynamic pressure constraint to ensure safe parachute deployment is complicated at Mars by low atmospheric density, high atmospheric uncertainty, and the desire to employ only bank angle control. The vehicle aerodynamic performance requirements and guidance necessary for 0.5 to 1.5 lift drag ratio vehicle to maximize the achievable footprint while meeting the constraints are examined. A parametric study of the various factors related to entry vehicle performance in the Mars environment is undertaken to develop general vehicle aerodynamic design requirements. The combination of low lift drag ratio and low atmospheric density at Mars result in a large phugoid motion involving the dynamic pressure which complicates trajectory control. Vehicle ballistic coefficient is demonstrated to be the predominant characteristic affecting final dynamic pressure. Additionally, a speed brake is shown to be ineffective at reducing the final dynamic pressure. An adaptive precision entry atmospheric guidance scheme is presented. The guidance uses a numeric predictor-corrector algorithm to control downrange, an azimuth controller to govern crossrange, and analytic control law to reduce the final dynamic pressure. Guidance performance is tested against a variety of dispersions, and the results from selected tests are presented. Precision entry using bank angle control only is demonstrated to be feasible at Mars.

  11. Rudder/Fin Seal Investigations for the X-38 Re-Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Dunlap, Patrick H., Jr.; Steinetz, Bruce M.; Curry, Donald M.

    2000-01-01

    NASA is currently developing the X-38 vehicle that will be used to demonstrate the technologies required for a crew return vehicle (CRV) for the International Space Station. The X-38 control surfaces require high temperature seals to limit hot gas ingestion and transfer of heat to underlying low-temperature structures to prevent over-temperature of these structures and possible loss of the vehicle. This paper presents results for thermal analyses and flow and compression tests conducted on as-received and thermally exposed seals for the rudder/fin location of the X-38. A thermal analysis of the rudder/fin dual seal assembly based on representative heating rates on the windward surface of the rudder/fin area predicted a peak seal temperature of 1900 F. The temperature-exposed seals were heated in a compressed state at 1900 F corresponding to the predicted peak temperature. Room temperature compression tests were performed to determine load versus linear compression, preload, contact area, stiffness, and resiliency characteristics for the as-received and temperature-exposed seals. Temperature exposure resulted in permanent set and loss of resiliency in these seals. Unit loads and contact pressures for the seals were below the five pounds/inch and ten psi limits set to limit the loads on the Shuttle thermal tiles that the seals seal against in the rudder/fin location. Measured seal flow rates for a double seal were about 4.5 times higher than the preliminary seal flow goal. The seal designs examined in this study are expected to be able to endure the high temperatures that they will be exposed to for a single-use life. Tests performed herein combined with future analyses, arc jet tests, and scrubbing tests will be used to select the final seal design for this application.

  12. Rudder/Fin Seal Investigations for the X-38 Re-Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Dunlap, Patrick H., Jr.; Steinetz, Bruce M.; Curry, Donald M.

    2000-01-01

    NASA is currently developing the X-38 vehicle that will be used to demonstrate the technologies required for a crew return vehicle (CRV) for the International Space Station. The X-38 control surfaces require high temperature seals to limit hot gas ingestion and transfer of heat to underlying low-temperature structures to prevent over-temperature of these structures and possible loss of the vehicle. This paper presents results for thermal analyses and flow and compression tests conducted on as-received and thermally exposed seals for the rudder/fin location of the X-38. A thermal analysis of the rudder/fin dual seal assembly based on representative heating rates on the windward surface of the rudder/fin area predicted a peak seal temperature of 1900 F. The temperature-exposed seals were heated in a compressed state at 1900 F corresponding to the predicted peak temperature. Room temperature compression tests were performed to determine load versus linear compression, preload, contact area, stiffness, and resiliency characteristics for the as-received and temperature-exposed seals. Temperature exposure resulted in permanent set and loss of resiliency in these seals. Unit loads and contact pressures for the seals were below the 5 lb/in. and 10 psi limits set to limit the loads on the Shuttle thermal tiles that the seals seal against in the rudder/fin location. Measured seal flow rates for a double seal were about 4.5 times higher than the preliminary seal flow goal. The seal designs examined in this study are expected to be able to endure the high temperatures that they will be exposed to for a single-use life. Tests performed herein combined with future analyses, arc jet tests, and scrubbing tests will be used to select the final seal design for this application.

  13. Landing Characteristics of a Re-entry Vehicle with a Passive Landing System for Impact Alleviation

    NASA Technical Reports Server (NTRS)

    Stubbs, Sandy M.

    1963-01-01

    An experimental investigation was made to determine the landing characteristics of a 1/8-scale dynamic model of a reentry vehicle using a passive landing system to alleviate the landing-impact loads. The passive landing system consisted of a flexible heat shield with a small section of aluminum honeycomb placed between the heat shield and the crew compartment at the point that would be the first to contact the landing surface. The model was landed on concrete and sand landing surfaces at parachute letdown velocities. The investigations simulated a vertical velocity of 30 ft/sec (full scale), horizontal velocities of 0, 15, 30, 40, and 50 ft/sec (full scale), and landing attitudes ranging from -30 degrees to 20 degrees. The model investigation indicated that stable landings could be made on a concrete surface at horizontal velocities up to about 30 ft/sec, but the stable landing-attitude range at these speeds was small. The aluminum honeycomb bottomed occasionally during landings on concrete. When bottoming did not occur, maximum normal and longitudinal accelerations at the center of gravity of the vehicle were approximately 50g and 30g, respectively.

  14. Aerothermodynamic environment and thermal protection for a Titan aerocapture vehicle. [Saturn satellite atmospheric entry

    NASA Technical Reports Server (NTRS)

    Green, M. J.; Moss, J. N.; Wilson, J. F.

    1984-01-01

    This paper presents thermal protection system (TPS) requirements for a potential Titan aerocapture vehicle. Shock-layer solutions are obtained for a nominal trajectory through the current Titan model atmosphere. Fully laminar and fully turbulent solutions are presented along the blunted fore-cone in the windward symmetry plane of a bent-biconic vehicle. Using these solutions to define the aerothermodynamic environment, transient material-response solutions are obtained for a Galileo-type TPS with a carbon-phenolic ablator heat shield. Shock-layer results indicate that turbulent flow is the more realistic flow condition. They also show that the lengthy aerocapture heating pulse is dominated by convective heating. The TPS results show that the required insulation thickness is uniformly about 4 cm along the fore-cone because of the long heat-soak period. The total heat-shield thickness is 6.4 cm at the stagnation point, and 4.7 cm near the end of the fore-cone. These TPS requirements are greater than those presented in a previous Titan aerocapture study.

  15. Phobetor: Princeton University's entry in the 2010 Intelligent Ground Vehicle Competition

    NASA Astrophysics Data System (ADS)

    Newman, Joshua; Zhu, Han; Partridge, Brenton A.; Szocs, Laszlo J.; Abiola, Solomon O.; Corey, Ryan M.; Suresh, Srinivasan A.; Yu, Derrick D.

    2011-01-01

    In this paper we present Phobetor, an autonomous outdoor vehicle originally designed for the 2010 Intelligent Ground Vehicle Competition (IGVC). We describe new vision and navigation systems that have yielded 3x increase in obstacle detection speed using parallel processing and robust lane detection results. Phobetor also uses probabilistic local mapping to learn about its environment and Anytime Dynamic A* (AD*) to plan paths to reach its goals. Our vision software is based on color stereo images and uses robust, RANSAC-based algorithms while running fast enough to support real-time autonomous navigation on uneven terrain. AD* allows Phobetor to respond quickly in all situations even when optimal planning takes more time, and uses incremental replanning to increase search efficiency. We augment the cost map of the environment with a potential field which addresses the problem of "wall-hugging" and smoothes generated paths to allow safe and reliable path-following. In summary, we present innovations on Phobetor that are relevant to real-world robotics platforms in uncertain environments.

  16. Using Navier-Stokes to Characterize Re-Entry of Microscale Vehicles

    NASA Astrophysics Data System (ADS)

    Thiruvenkadam, Sudharsan; Ben, Harris

    2013-11-01

    Atmospheric reentry vehicles experience different flow regimes during flight due to the change in atmospheric density. This change in density creates non-equilibrium regions on the order of one mean free path, called as Knudsen layer. In the design of atmospheric reentry vehicles, the flux variations near solid surface are of critical importance. The traditional CFD simulations which use Navier Stokes equations fail to predict the flow in Knudsen layer. These areas where the rarefaction effects begin to dominate can be quantified by the Knudsen breakdown parameter. The Direct Simulation Monte Carlo (DSMC) method, although accurate for all flow regimes, it is computationally expensive as the number of simulating molecules increases. We developed a method that models the Knudsen Layer by using Navier Stokes equations with Maxwell-Smoluchowski slip boundary conditions and DSMC for low (Kn < 0.1) and high (Kn > 0.1) Knudsen numbers respectively. This study investigates the surface properties of a flat plate with Nitrogen gas flow from continuum to rarefied regimes. Computational fluid dynamics and DSMC results are obtained for different test conditions. The results demonstrate that the Knudsen layer can be predicted with DSMC and continuum approach for all flow regimes.

  17. 41 CFR 102-34.70 - What do we do with completed calculations of our fleet vehicle acquisitions?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false What do we do with completed calculations of our fleet vehicle acquisitions? 102-34.70 Section 102-34.70 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 34-MOTOR...

  18. Emergency Scenarios of a Re-Entry Vehicle due to Control Degradation

    NASA Astrophysics Data System (ADS)

    da Costa, O.; Sachs, G.

    A controls degradation scenario is investigated for a reentry vehicle. It is assumed that one of two body flaps is blocked. The reaction control system is used to generate control moments in combination with the aerodynamic surfaces still operative. Particular emphasis is placed on implementing a control allocation method which yields an optimum utilization of the aerodynamic control surfaces in terms of minimizing the propellant mass required for the reaction control system. Minimum-propellant trajectories for the blocked body flap scenarios are determined using an efficient optimization technique. Results are presented which address blocked body flap scenarios caused by off-normal situations already in the orbital phase. The results show that no additional landing sites are required if an adequate amount of propellant mass is available.

  19. Argos: Princeton University's entry in the 2009 Intelligent Ground Vehicle Competition

    NASA Astrophysics Data System (ADS)

    Abiola, Solomon O.; Baldassano, Christopher A.; Franken, Gordon H.; Harris, Richard J.; Hendrick, Barbara A.; Mayer, Jonathan R.; Partridge, Brenton A.; Starr, Eric W.; Tait, Alexander N.; Yu, Derrick D.; Zhu, Tony H.

    2010-01-01

    In this paper, we present Argos, an autonomous ground robot built for the 2009 Intelligent Ground Vehicle Competition (IGVC). Discussed are the significant improvements over its predecessor from the 2008 IGVC, Kratos. We continue to use stereo vision techniques to generate a cost map of the environment around the robot. Lane detection is improved through the use of color filters that are robust to changing lighting conditions. The addition of a single-axis gyroscope to the sensor suite allows accurate measurement of the robot's yaw rate and compensates for wheel slip, vastly improving state estimation. The combination of the D* Lite algorithm, which avoids unnecessary re-planning, and the Field D* algorithm, which allows us to plan much smoother paths, results in an algorithm that produces higher quality paths in the same amount of time as methods utilizing A*. The successful implementation of a crosstrack error navigation law allows the robot to follow planned paths without cutting corners, reducing the chance of collision with obstacles. A redesigned chassis with a smaller footprint and a bi-level design, combined with a more powerful drivetrain, makes Argos much more agile and maneuverable compared to its predecessor. At the 2009 IGVC, Argos placed first in the Navigation Challenge.

  20. Digital data acquisition and preliminary instrumentation study for the F-16 laminar flow control vehicle

    NASA Technical Reports Server (NTRS)

    Ostowari, Cyrus

    1992-01-01

    Preliminary studies have shown that maintenance of laminar flow through active boundary-layer control is viable. Current research activity at NASA Langley and NASA Dryden is utilizing the F-16XL-1 research vehicle fitted with a laminar-flow suction glove that is connected to a vacuum manifold in order to create and control laminar flow at supersonic flight speeds. This experimental program has been designed to establish the feasibility of obtaining laminar flow at supersonic speeds with highly swept wing and to provide data for computational fluid dynamics (CFD) code calibration. Flight experiments conducted as supersonic speeds have indicated that it is possible to achieve laminar flow under controlled suction at flight Mach numbers greater than 1. Currently this glove is fitted with a series of pressure belts and flush mounted hot film sensors for the purpose of determining the pressure distributions and the extent of laminar flow region past the stagnation point. The present mode of data acquisition relies on out-dated on board multi-channel FM analogue tape recorder system. At the end of each flight, the analogue data is digitized through a long laborious process and then analyzed. It is proposed to replace this outdated system with an on board state-of-the-art digital data acquisition system capable of a through put rate of up to 1 MegaHertz. The purpose of this study was three-fold: (1) to develop a simple algorithm for acquiring data via 2 analogue-to-digital convertor boards simultaneously (total of 32 channels); (2) to interface hot-film/wire anemometry instrumentation with a PCAT type computer; and (3) to characterize the frequency response of a flush mounted film sensor. A brief description of each of the above tasks along with recommendations are given.

  1. The application of quaternions and other spatial representations to the reconstruction of re-entry vehicle motion.

    SciTech Connect

    De Sapio, Vincent

    2010-09-01

    The analysis of spacecraft kinematics and dynamics requires an efficient scheme for spatial representation. While the representation of displacement in three dimensional Euclidean space is straightforward, orientation in three dimensions poses particular challenges. The unit quaternion provides an approach that mitigates many of the problems intrinsic in other representation approaches, including the ill-conditioning that arises from computing many successive rotations. This report focuses on the computational utility of unit quaternions and their application to the reconstruction of re-entry vehicle (RV) motion history from sensor data. To this end they will be used in conjunction with other kinematic and data processing techniques. We will present a numerical implementation for the reconstruction of RV motion solely from gyroscope and accelerometer data. This will make use of unit quaternions due to their numerical efficacy in dealing with the composition of many incremental rotations over a time series. In addition to signal processing and data conditioning procedures, algorithms for numerical quaternion-based integration of gyroscope data will be addressed, as well as accelerometer triangulation and integration to yield RV trajectory. Actual processed flight data will be presented to demonstrate the implementation of these methods.

  2. Specific Plasma Ionospheric Excitations Modes in the Ionosphere Produced by Space Vehicle Launch and RE Entry and Natural Phenomena

    NASA Astrophysics Data System (ADS)

    Rauscher, E. A.; van Bise, W. L.

    2001-10-01

    SPECIFIC PLASMA IONOSPHERIC EXCITATIONS MODES IN THE IONOSPHERE PRODUCED BY SPACE VEHICLE LAUNCH AND RE ENTRY AND NATURAL PHENOMENA We have examined both experimentally and theoretically the formation and excitation of highly well defined specific wave forms of plasma excitation in the D, E, F(1) and F(2) and sometimes G layers of the earth?s ionosphere. In our formal study period from October 1989 until December 1996, we measured 41 distinct events out of a possible 73 events utilizing ground based sensitive T1050 magnetometers. In five cases more than two to three stations were displayed and detected the same ionospheric excitations. Sometimes background noise was high and dominated the signals, but under good measurement conditions signals appeared to be 50 to 70 dbm over the background noise floor. Specific frequencies of the D-layer appeared around 5.2 to 6.52 Hz and E layer excitations were from 10.48 to 12.8 Hz. Sometimes an F double peak appeared around 15 to 17 Hz as excited by space shuttle activity and delta rockets and in several cases, large scale volcanism. A theoretical model has been developed which describes sustained long duration and long range coherent plasma excitation modes which occur when the ionospheric layers are shock excited. Alfven-like velocities of propogation are calculated in these ionospheric layer. Some Schumann resonates were observed from 7 to 8 Hz.

  3. Angular and Linear Velocity Estimation for a Re-Entry Vehicle Using Six Distributed Accelerometers: Theory, Simulation and Feasibility

    SciTech Connect

    Clark, G

    2003-04-28

    This report describes a feasibility study. We are interested in calculating the angular and linear velocities of a re-entry vehicle using six acceleration signals from a distributed accelerometer inertial measurement unit (DAIMU). Earlier work showed that angular and linear velocity calculation using classic nonlinear ordinary differential equation (ODE) solvers is not practically feasible, due to mathematical and numerical difficulties. This report demonstrates the theoretical feasibility of using model-based nonlinear state estimation techniques to obtain the angular and linear velocities in this problem. Practical numerical and calibration issues require additional work to resolve. We show that the six accelerometers in the DAIMU are not sufficient to provide observability, so additional measurements of the system states are required (e.g. from a Global Positioning System (GPS) unit). Given the constraint that our system cannot use GPS, we propose using the existing on-board 3-axis magnetometer to measure angular velocity. We further show that the six nonlinear ODE's for the vehicle kinematics can be decoupled into three ODE's in the angular velocity and three ODE's in the linear velocity. This allows us to formulate a three-state Gauss-Markov system model for the angular velocities, using the magnetometer signals in the measurement model. This re-formulated model is observable, allowing us to build an Extended Kalman Filter (EKF) for estimating the angular velocities. Given the angular velocity estimates from the EKF, the three ODE's for the linear velocity become algebraic, and the linear velocity can be calculated by numerical integration. Thus, we do not need direct measurements of the linear velocity to provide observability, and the technique is mathematically feasible. Using a simulation example, we show that the estimator adds value over the numerical ODE solver in the presence of measurement noise. Calculating the velocities in the presence of

  4. Experimental Aeroheating Study of Mid-L/D Entry Vehicle Geometries: NASA LaRC 20-Inch Mach 6 Air Tunnel Test 6966

    NASA Technical Reports Server (NTRS)

    Hollis, Brian R.; Hollingsworth, Kevin E.

    2014-01-01

    Aeroheating data on mid lift-to-drag ratio entry vehicle configurations has been obtained through hypersonic wind tunnel testing. Vehicles of this class have been proposed for high-mass Mars missions, such as sample return and crewed exploration, for which the conventional sphere-cone entry vehicle geometries of previous Mars missions are insufficient. Several configurations were investigated, including elliptically-blunted cylinders with both circular and elliptical cross sections, biconic geometries based on launch vehicle dual-use shrouds, and parametrically-optimized analytic geometries. Testing was conducted at Mach 6 over a range of Reynolds numbers sufficient to generate laminar, transitional, and turbulent flow. Global aeroheating data were obtained using phosphor thermography. Both stream-wise and cross-flow transition occured on different configurations. Comparisons were made with laminar and turbulent computational predictions generated with an algebraic turbulence model. Predictions were generally in good agreement in regions of laminar or fully-turbulent flow; however for transitional cases, the lack of a transition onset prediction capability produced less accurate comparisons. The data obtained in this study are intended to be used for prelimary mission design studies and the development and validation of computational methods.

  5. Atmospheric Entry Studies for Uranus

    NASA Astrophysics Data System (ADS)

    Agrawal, P.; Allen, G. A.; Hwang, H. H.; Marley, M. S.; McGuire, M. K.; Garcia, J. A.; Sklyanskiy, E.; Huynh, L. C.; Moses, R. W.

    2014-07-01

    To better understand the technology requirements for Uranus atmospheric entry probe, Entry Vehicle Technology project funded an internal study with a multidisciplinary team from NASA Ames, Langley and JPL. The results of this study are communicated.

  6. 48 CFR 908.7101-2 - Consolidated acquisition of new vehicles by General Services Administration.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Management Regulations (DOE-PMR) 41 CFR 109-26.501. Orders for all motor vehicles must be placed utilizing... submitted utilizing GSA's on-line system (Auto Choice), in accordance with FPMR 41 CFR 101-26.501... Services Administration. (a) New vehicles shall be procured in accordance with Federal Property...

  7. 48 CFR 908.7101-2 - Consolidated acquisition of new vehicles by General Services Administration.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Management Regulations (DOE-PMR) 41 CFR 109-26.501. Orders for all motor vehicles must be placed utilizing... submitted utilizing GSA's on-line system (Auto Choice), in accordance with FPMR 41 CFR 101-26.501... Services Administration. (a) New vehicles shall be procured in accordance with Federal Property...

  8. Acquisition, orthorectification, and object-based classification of unmanned aerial vehicle (UAV) imagery for rangeland monitoring

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this paper, we examine the potential of using a small unmanned aerial vehicle (UAV) for rangeland inventory, assessment and monitoring. Imagery with 8-cm resolution was acquired over 290 ha in southwestern Idaho. We developed a semi-automated orthorectification procedure suitable for handling lar...

  9. Multi-modal assessment of on-road demand of voice and manual phone calling and voice navigation entry across two embedded vehicle systems

    PubMed Central

    Mehler, Bruce; Kidd, David; Reimer, Bryan; Reagan, Ian; Dobres, Jonathan; McCartt, Anne

    2016-01-01

    Abstract One purpose of integrating voice interfaces into embedded vehicle systems is to reduce drivers’ visual and manual distractions with ‘infotainment’ technologies. However, there is scant research on actual benefits in production vehicles or how different interface designs affect attentional demands. Driving performance, visual engagement, and indices of workload (heart rate, skin conductance, subjective ratings) were assessed in 80 drivers randomly assigned to drive a 2013 Chevrolet Equinox or Volvo XC60. The Chevrolet MyLink system allowed completing tasks with one voice command, while the Volvo Sensus required multiple commands to navigate the menu structure. When calling a phone contact, both voice systems reduced visual demand relative to the visual–manual interfaces, with reductions for drivers in the Equinox being greater. The Equinox ‘one-shot’ voice command showed advantages during contact calling but had significantly higher error rates than Sensus during destination address entry. For both secondary tasks, neither voice interface entirely eliminated visual demand. Practitioner Summary: The findings reinforce the observation that most, if not all, automotive auditory–vocal interfaces are multi-modal interfaces in which the full range of potential demands (auditory, vocal, visual, manipulative, cognitive, tactile, etc.) need to be considered in developing optimal implementations and evaluating drivers’ interaction with the systems. Social Media: In-vehicle voice-interfaces can reduce visual demand but do not eliminate it and all types of demand need to be taken into account in a comprehensive evaluation. PMID:26269281

  10. Multi-modal assessment of on-road demand of voice and manual phone calling and voice navigation entry across two embedded vehicle systems.

    PubMed

    Mehler, Bruce; Kidd, David; Reimer, Bryan; Reagan, Ian; Dobres, Jonathan; McCartt, Anne

    2016-03-01

    One purpose of integrating voice interfaces into embedded vehicle systems is to reduce drivers' visual and manual distractions with 'infotainment' technologies. However, there is scant research on actual benefits in production vehicles or how different interface designs affect attentional demands. Driving performance, visual engagement, and indices of workload (heart rate, skin conductance, subjective ratings) were assessed in 80 drivers randomly assigned to drive a 2013 Chevrolet Equinox or Volvo XC60. The Chevrolet MyLink system allowed completing tasks with one voice command, while the Volvo Sensus required multiple commands to navigate the menu structure. When calling a phone contact, both voice systems reduced visual demand relative to the visual-manual interfaces, with reductions for drivers in the Equinox being greater. The Equinox 'one-shot' voice command showed advantages during contact calling but had significantly higher error rates than Sensus during destination address entry. For both secondary tasks, neither voice interface entirely eliminated visual demand. Practitioner Summary: The findings reinforce the observation that most, if not all, automotive auditory-vocal interfaces are multi-modal interfaces in which the full range of potential demands (auditory, vocal, visual, manipulative, cognitive, tactile, etc.) need to be considered in developing optimal implementations and evaluating drivers' interaction with the systems. Social Media: In-vehicle voice-interfaces can reduce visual demand but do not eliminate it and all types of demand need to be taken into account in a comprehensive evaluation. PMID:26269281

  11. Supersonic Testing of 0.8 m Disk Gap Band Parachutes in the Wake of a 70 Deg Sphere Cone Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Sengupta, Anita; Wernet, Mark; Roeder, James; Kelsch, Richard; Witkowski, Al; Jones, Thomas

    2009-01-01

    Supersonic wind tunnel testing of Viking-type 0.8 m Disk-Gap-Band (DGB) parachutes was conducted in the NASA Glenn Research Center 10'x10' wind-tunnel. The tests were conducted in support of the Mars Science Laboratory Parachute Decelerator System development and qualification program. The aerodynamic coupling of the entry-vehicle wake to parachute flow-field is under investigation to determine the cause and functional dependence of a supersonic canopy breathing phenomenon referred to as area oscillations, characteristic of DGB's above Mach 1.5 operation. Four percent of full-scale parachutes (0.8 m) were constructed similar to the flight-article in material and construction techniques. The parachutes were attached to a 70-deg sphere-cone entry-vehicle to simulate the Mars flight configuration. The parachutes were tested in the wind-tunnel from Mach 2 to 2.5 in a Reynolds number range of 2x105 to 1x106, representative of a Mars deployment. Three different test configurations were investigated. In the first two configurations, the parachutes were constrained horizontally through the vent region to measure canopy breathing and wake interaction for fixed trim angles of 0 and 10 degrees from the free-stream. In the third configuration the parachute was unconstrained, permitted to trim and cone, similar to free-flight (but capsule motion is constrained), varying its alignment relative to the entry-vehicle wake. Non-intrusive test diagnostics were chosen to quantify parachute performance and provide insight into the flow field structure. An in-line loadcell provided measurement of unsteady and mean drag. Shadowgraph of the upstream parachute flow field was used to capture bow-shock motion and wake coupling. Particle image velocimetry provided first and second order flow field statistics over a planar region of the flow field, just upstream of the parachute. A photogrammetric technique was used to quantify fabric motion using multiple high speed video cameras to record

  12. 48 CFR 908.7101-2 - Consolidated acquisition of new vehicles by General Services Administration.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Services Administration. (a) New vehicles shall be procured in accordance with FPMR 41 CFR 101-25.304, 101-26.501, and 101-38.13, and DOE-PMR 41 CFR 109-25.304, 109-38.13, and 109-38.51. (b) Orders for all... accordance with FPMR 41 CFR 101-26.501. Requisitions for sedans, station wagons, and certain light trucks...

  13. Multimodal Perception and Multicriterion Control of Nested Systems. 2; Constraints on Crew Members During Space Vehicle Abort, Entry, and Landing

    NASA Technical Reports Server (NTRS)

    Riccio, Gary E.; McDonald, P. Vernon; Irvin, Gregg E.; Bloomberg, Jacob J.

    1998-01-01

    This report reviews the operational demands made of a Shuttle pilot or commander within the context of a proven empirical methodology for describing human sensorimotor performance and whole-body coordination in mechanically and perceptually complex environments. The conclusions of this review pertain to a) methods for improving our understanding of the psychophysics and biomechanics of visual/manual control and whole-body coordination in space vehicle cockpits; b) the application of scientific knowledge about human perception and performance in dynamic inertial conditions to the development of technology, procedures, and training for personnel in space vehicle cockpits; c) recommendations for mitigation of safety and reliability concerns about human performance in space vehicle cockpits; and d) in-flight evaluation of flight crew performance during nominal and off-nominal launch and reentry scenarios.

  14. The Acquisition Process as a Vehicle for Enabling Knowledge Management in the Lifecycle of Complex Federal Systems

    NASA Technical Reports Server (NTRS)

    Stewart, Helen; Spence, Matt Chew; Holm, Jeanne; Koga, Dennis (Technical Monitor)

    2001-01-01

    This white paper explores how to increase the success and operation of critical, complex, national systems by effectively capturing knowledge management requirements within the federal acquisition process. Although we focus on aerospace flight systems, the principles outlined within may have a general applicability to other critical federal systems as well. Fundamental design deficiencies in federal, mission-critical systems have contributed to recent, highly visible system failures, such as the V-22 Osprey and the Delta rocket family. These failures indicate that the current mechanisms for knowledge management and risk management are inadequate to meet the challenges imposed by the rising complexity of critical systems. Failures of aerospace system operations and vehicles may have been prevented or lessened through utilization of better knowledge management and information management techniques.

  15. 49 CFR Appendix A to Part 591 - Section 591.5(f) Bond for the Entry of a Single Vehicle

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., pursuant to 49 CFR part 591, a regulation promulgated under the provisions of 49 U.S.C. Chapter 301, the... bumper standards; and WHEREAS, pursuant to 49 CFR part 592, a regulation promulgated under the provisions... the vehicle described above); and WHEREAS, pursuant to 49 CFR part 593, a regulation promulgated...

  16. Atmospheric Entry Studies for Uranus

    NASA Technical Reports Server (NTRS)

    Agrawal, Parul; Allen, Gary A.; Hwang, Helen; Prabhu, Dinesh; Aliaga, Jose; Marley, Mark; McGuire, Kathy; Huynh, Loc; Garcia, Joseph; Moses, Robert; Winski, Rick; Skylanskiy, Evgeniy

    2013-01-01

    The Objectives of this work are: 1) Establish a range of probe atmospheric entry environments based on the Uranus Flagship mission outlined in the Planetary Science Decadal Survey for two launch windows: Year 2021 and 2034. 2) Define Uranus entry trade space by performing parametric studies, by varying vehicle mass and size and entry Flight Path Angle (FPA). 3) Investigate various trajectory options, including direct ballistic entry and aero-capture entry. 4) Identify entry technologies that could be leveraged to enable a viable mission to Uranus that meets science objectives.

  17. Finite-rate chemistry effects upon convective and radiative heating of an atmospheric entry vehicle. [reentry aerothermochemistry

    NASA Technical Reports Server (NTRS)

    Guillermo, P.

    1975-01-01

    A mathematical model of the aerothermochemical environment along the stagnation line of a planetary return spacecraft using an ablative thermal protection system was developed and solved for conditions typical of atmospheric entry from planetary missions. The model, implemented as a FORTRAN 4 computer program, was designed to predict viscous, reactive and radiative coupled shock layer structure and the resulting body heating rates. The analysis includes flow field coupling with the ablator surface, binary diffusion, coupled line and continuum radiative and equilibrium or finite rate chemistry effects. The gas model used includes thermodynamic, transport, kinetic and radiative properties of air and ablation product species, including 19 chemical species and 16 chemical reactions. Specifically, the impact of nonequilibrium chemistry effects upon stagnation line shock layer structure and body heating rates was investigated.

  18. Roughness Estimation from Point Clouds - A Comparison of Terrestrial Laser Scanning and Image Matching by Unmanned Aerial Vehicle Acquisitions

    NASA Astrophysics Data System (ADS)

    Rutzinger, Martin; Bremer, Magnus; Ragg, Hansjörg

    2013-04-01

    Recently, terrestrial laser scanning (TLS) and matching of images acquired by unmanned arial vehicles (UAV) are operationally used for 3D geodata acquisition in Geoscience applications. However, the two systems cover different application domains in terms of acquisition conditions and data properties i.e. accuracy and line of sight. In this study we investigate the major differences between the two platforms for terrain roughness estimation. Terrain roughness is an important input for various applications such as morphometry studies, geomorphologic mapping, and natural process modeling (e.g. rockfall, avalanche, and hydraulic modeling). Data has been collected simultaneously by TLS using an Optech ILRIS3D and a rotary UAV using an octocopter from twins.nrn for a 900 m² test site located in a riverbed in Tyrol, Austria (Judenbach, Mieming). The TLS point cloud has been acquired from three scan positions. These have been registered using iterative closest point algorithm and a target-based referencing approach. For registration geometric targets (spheres) with a diameter of 20 cm were used. These targets were measured with dGPS for absolute georeferencing. The TLS point cloud has an average point density of 19,000 pts/m², which represents a point spacing of about 5 mm. 15 images where acquired by UAV in a height of 20 m using a calibrated camera with focal length of 18.3 mm. A 3D point cloud containing RGB attributes was derived using APERO/MICMAC software, by a direct georeferencing approach based on the aircraft IMU data. The point cloud is finally co-registered with the TLS data to guarantee an optimal preparation in order to perform the analysis. The UAV point cloud has an average point density of 17,500 pts/m², which represents a point spacing of 7.5 mm. After registration and georeferencing the level of detail of roughness representation in both point clouds have been compared considering elevation differences, roughness and representation of different grain

  19. Effect of configuration modification on the hypersonic aerodynamic characteristics of a blended delta wing-body entry vehicle

    NASA Technical Reports Server (NTRS)

    Arrington, J. P.; Ashby, G. C., Jr.

    1972-01-01

    The longitudinal, lateral, and directional aerodynamic characteristics of a delta-wing configuration were obtained experimentally at Mach 20 in helium with Reynolds numbers, based on model length, of 1.5 million and 2.9 million and at a Mach number of 6 in air with a Reynolds number, based on model length, of 4.8 million. The angles of attack varied from 0 deg to 55 deg for two sideslip angles. The effects of the addition of dorsal fins, the removal of wing tip fins, an increase in elevon span, and changes in elevon hinge-line sweep angle are discussed. The unmodified vehicle had a maximum lift-drag ratio of 2.1 at Mach 19 and of 2.4 at Mach 6 with about the same lateral and directional stability level at both Mach numbers. As the Mach number increased from 6 to 20, the longitudinal center of pressure moved forward and more positive elevon deflection was therefore required to maintain a given trim angle. The removal of wing tip fins increased the maximum lift-drag ratio and had a negligible effect on longitudinal stability, but caused directional instability that was not corrected by the dorsal fins examined. The shape of the wing and elevon hinge-line sweep had a large influence on the induced yawing moment due to roll control.

  20. Heat transfer and oil flow studies on a single-stage-to-orbit control-configured winged entry vehicle

    NASA Technical Reports Server (NTRS)

    Helms, V. T., III; Bradley, P. F.

    1984-01-01

    Results are presented for oil flow and phase change paint heat transfer tests conducted on a 0.006 scale model of a proposed single stage to orbit control configured vehicle. The data were taken at angles of attack up to 40 deg at a free stream Mach number of 10 for Reynolds numbers based on model length of 0.5 x 10 to the 6th power, 1.0 x 10 to the 6th power and 2.0 x 10 to the 6th power. The magnitude and distribution of heating are characterized in terms of angle of attack and Reynolds number aided by an analysis of the flow data which are used to suggest the presence of various three dimensional flow structures that produce the observed heating patterns. Of particular interest are streak heating patterns that result in high localized heat transfer rates on the wing windward surface at low to moderate angles of attack. These streaks are caused by the bow-shock/wing-shock interaction and formation of the wing-shock. Embedded vorticity was found to be associated with these interactions.

  1. Effect of wing sweep, angle of attack, Reynolds number, and wing root fillet on the interference heating to the wing windward surface of an entry vehicle configuration

    NASA Technical Reports Server (NTRS)

    Clark, L. E.

    1972-01-01

    The phase-change-coating technique was used to study the interference heating to the windward surface of 14 deg, 25 deg, and 50 deg swept wings of an entry vehicle configuration. One wing root of each model was faired to the fuselage with a fillet. Tests were made at Mach 8 at angles of attack of 0 deg, 20 deg, 40 deg, and 60 deg and at free-stream Reynolds numbers based on model length of 0.47 and 1.7 million. Bow shock impingement heating was found to increase in magnitude and affected area with increasing angle of attack until at a higher angle of attack it decreases; this angle of attack is lower for a 50 deg swept wing. Wing root interference heating was found to increase with angle of attack up to 40 deg and then to remain approximately constant. Consequently, wing root interference heating becomes the major type of interference heating at large angles of attack, and this occurs at a lower angle of attack for the highest sweep angle. A wing leading-edge root fillet reduces the peak in wing root interference heating near the leading edge, and increasing Reynolds number increases the level of interference heating.

  2. Re-entry Experiment Launch

    NASA Video Gallery

    On August 10, 2009, NASA successfully launched the Inflatable Re-entry Vehicle Experiment (IRVE) and proved that spacecraft can use inflatable heat shields to reduce speed and provide protection du...

  3. Space assembled entry systems certification

    NASA Technical Reports Server (NTRS)

    Curry, Donald M.

    1993-01-01

    The approach taken to the issue, that 'How do you say you're 'good for go' if you space assemble an entry vehicle?', are: (1) shuttle orbiter thermal protection certification; (2) shuttle thermal protection system flight experience; and (3) space assembled entry system certification.

  4. 48 CFR 5.003 - Governmentwide point of entry.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Governmentwide point of entry. 5.003 Section 5.003 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION ACQUISITION PLANNING PUBLICIZING CONTRACT ACTIONS 5.003 Governmentwide point of entry. For any requirement...

  5. 48 CFR 5.003 - Governmentwide point of entry.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Governmentwide point of entry. 5.003 Section 5.003 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION ACQUISITION PLANNING PUBLICIZING CONTRACT ACTIONS 5.003 Governmentwide point of entry. For any requirement...

  6. Traffic-related air pollution in the community of San Ysidro, CA, in relation to northbound vehicle wait times at the US-Mexico border Port of Entry

    NASA Astrophysics Data System (ADS)

    Quintana, Penelope J. E.; Dumbauld, Jill J.; Garnica, Lynelle; Chowdhury, M. Zohir; Velascosoltero, José; Mota-Raigoza, Arturo; Flores, David; Rodríguez, Edgar; Panagon, Nicolas; Gamble, Jamison; Irby, Travis; Tran, Cuong; Elder, John; Galaviz, Vanessa E.; Hoffman, Lisa; Zavala, Miguel; Molina, Luisa T.

    2014-05-01

    The San Diego/Tijuana US-Mexico border crossing at the San Ysidro Port of Entry (POE) is the world's busiest international land border crossing (GSA, 2013). San Ysidro, California, is the US community immediately adjacent to the border crossing. More than 90% of San Ysidro residents are Hispanic, and the average household income is less than 60% of the San Diego regional average. This study investigated the San Ysidro POE as a source of traffic-related air pollutants in San Ysidro, especially in relation to wind direction and northbound vehicle wait times. The pollutants ultrafine particulate matter (UFP), black carbon (BC), and particulate matter <2.5 μm in diameter (PM2.5) were periodically sampled through the course of 2010 at four rooftop locations: one commercial establishment near the POE, two elementary schools in San Ysidro, and a coastal estuary reference site. Weather data from two nearby sites and northbound border wait times were also collected. Results indicate consistently higher daytime BC and UFP concentrations at the measurement sites near the POE. Pollution concentrations were higher during low wind speeds or when wind was blowing from the POE towards San Ysidro. In February, March and November measurements, black carbon pollution appeared to be significantly positively associated with the POE northbound wait times when the wind direction was blowing from the POE towards San Ysidro or during low wind speeds, but not when the wind direction was from the west/northwest towards the POE. This pilot study is the first to investigate the potential effect of the POE, especially the long northbound traffic delays, on the nearby community of San Ysidro. Disparities in traffic exposures are an environmental justice issue and this should be taken into account during planning and operation of POEs.

  7. Planetary/DOD entry technology flight experiments. Volume 2: Planetary entry flight experiments

    NASA Technical Reports Server (NTRS)

    Christensen, H. E.; Krieger, R. J.; Mcneilly, W. R.; Vetter, H. C.

    1976-01-01

    The technical feasibility of launching a high speed, earth entry vehicle from the space shuttle to advance technology for the exploration of the outer planets' atmospheres was established. Disciplines of thermodynamics, orbital mechanics, aerodynamics propulsion, structures, design, electronics and system integration focused on the goal of producing outer planet environments on a probe shaped vehicle during an earth entry. Major aspects of analysis and vehicle design studied include: planetary environments, earth entry environment capability, mission maneuvers, capabilities of shuttle upper stages, a comparison of earth entry planetary environments, experiment design and vehicle design.

  8. Flowfield computation of entry vehicles

    NASA Technical Reports Server (NTRS)

    Prabhu, Dinesh K.

    1990-01-01

    The equations governing the multidimensional flow of a reacting mixture of thermally perfect gasses were derived. The modeling procedures for the various terms of the conservation laws are discussed. A numerical algorithm, based on the finite-volume approach, to solve these conservation equations was developed. The advantages and disadvantages of the present numerical scheme are discussed from the point of view of accuracy, computer time, and memory requirements. A simple one-dimensional model problem was solved to prove the feasibility and accuracy of the algorithm. A computer code implementing the above algorithm was developed and is presently being applied to simple geometries and conditions. Once the code is completely debugged and validated, it will be used to compute the complete unsteady flow field around the Aeroassist Flight Experiment (AFE) body.

  9. 41 CFR 102-34.70 - What do we do with completed calculations of our fleet vehicle acquisitions?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 34-MOTOR VEHICLE MANAGEMENT Obtaining Fuel Efficient Motor Vehicles § 102-34.70... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false What do we do...

  10. 41 CFR 102-34.70 - What do we do with completed calculations of our fleet vehicle acquisitions?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 34-MOTOR VEHICLE MANAGEMENT Obtaining Fuel Efficient Motor Vehicles § 102-34.70... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false What do we do...

  11. 41 CFR 102-34.80 - Where may we obtain help with our motor vehicle acquisition plans?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 34-MOTOR VEHICLE MANAGEMENT Obtaining Fuel Efficient Motor Vehicles § 102-34.80 Where may we... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Where may we obtain...

  12. 41 CFR 102-34.70 - What do we do with completed calculations of our fleet vehicle acquisitions?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 34-MOTOR VEHICLE MANAGEMENT Obtaining Fuel Efficient Motor Vehicles § 102-34.70... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false What do we do...

  13. 41 CFR 102-34.80 - Where may we obtain help with our motor vehicle acquisition plans?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 34-MOTOR VEHICLE MANAGEMENT Obtaining Fuel Efficient Motor Vehicles § 102-34.80 Where may we... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Where may we obtain...

  14. 41 CFR 102-34.80 - Where may we obtain help with our motor vehicle acquisition plans?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 34-MOTOR VEHICLE MANAGEMENT Obtaining Fuel Efficient Motor Vehicles § 102-34.80 Where may we... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Where may we obtain...

  15. Design and demonstrate the performance of cryogenic components representative of space vehicles: Start basket liquid acquisition device performance analysis

    NASA Technical Reports Server (NTRS)

    1987-01-01

    The objective was to design, fabricate and test an integrated cryogenic test article incorporating both fluid and thermal propellant management subsystems. A 2.2 m (87 in) diameter aluminum test tank was outfitted with multilayer insulation, helium purge system, low-conductive tank supports, thermodynamic vent system, liquid acquisition device and immersed outflow pump. Tests and analysis performed on the start basket liquid acquisition device and studies of the liquid retention characteristics of fine mesh screens are discussed.

  16. Aerodynamic damping and oscillatory stability in pitch of a model of a proposed manned lifting entry vehicle at Mach Numbers of 1.80, 2.16, and 2.86

    NASA Technical Reports Server (NTRS)

    Kilgore, R. A.; Davenport, E. E.

    1975-01-01

    Wind tunnel tests were conducted using a model of a proposed manned lifting entry vehicle to determine the aerodynamic damping and oscillatory stability in pitch. The model was tested at Mach numbers of 1.80, 2.16, and 2.86. Angles of attack varied from minus 2 degrees to plus 30 degrees at zero angle of sideslip using a small-amplitude, forced-oscillation technique. It was determined that, in general, all the configurations have near zero or slightly positive damping in pitch throughout the angle of attack range. The effects of the deflection of flaps on aerodynamic damping are discussed.

  17. Viking entry aerodynamics and heating

    NASA Technical Reports Server (NTRS)

    Polutchko, R. J.

    1974-01-01

    The characteristics of the Mars entry including the mission sequence of events and associated spacecraft weights are described along with the Viking spacecraft. Test data are presented for the aerodynamic characteristics of the entry vehicle showing trimmed alpha, drag coefficient, and trimmed lift to drag ratio versus Mach number; the damping characteristics of the entry configuration; the angle of attack time history of Viking entries; stagnation heating and pressure time histories; and the aeroshell heating distribution as obtained in tests run in a shock tunnel for various gases. Flight tests which demonstrate the aerodynamic separation of the full-scale aeroshell and the flying qualities of the entry configuration in an uncontrolled mode are documented. Design values selected for the heat protection system based on the test data and analysis performed are presented.

  18. Capillary acquisition devices for high-performance vehicles: Executive summary. [evaluation of cryogenic propellant management techniques using the centaur launch vehicle

    NASA Technical Reports Server (NTRS)

    Blatt, M. H.; Bradshaw, R. D.; Risberg, J. A.

    1980-01-01

    Technology areas critical to the development of cryogenic capillary devices were studied. Passive cooling of capillary devices was investigated with an analytical and experimental study of wicking flow. Capillary device refilling with settled fluid was studied using an analytical and experimental program that resulted in successful correlation of a versatile computer program with test data. The program was used to predict Centaur D-1S LO2 and LH2 start basket refilling. Comparisons were made between the baseline Centaur D-1S propellant feed system and feed system alternatives including systems using capillary devices. The preferred concepts from the Centaur D-1S study were examined for APOTV and POTV vehicles for delivery and round trip transfer of payloads between LEO and GEO. Mission profiles were determined to provide propellant usage timelines and the payload partials were defined.

  19. Acquisition of Long-Duration, Low-Gravity Slosh Data Utilizing Existing ISS Equipment (SPHERES) for Calibration of CFD Models of Coupled Fluid-Vehicle Behavior

    NASA Technical Reports Server (NTRS)

    Schallhorn, Paul; Roth, Jacob; Marsell, Brandon; Kirk, Daniel; Gutierrez, Hector; Saenz-Otero, Alvar; Dorney, Daniel; Moder, Jeffrey

    2013-01-01

    simulates a launch vehicle upper stage propellant tank and the maneuvers replicate those of real vehicles. The design includes inertial sensors, data acquisition, image capture and data storage interfaces to the SPHERES VERTIGO computer system on board the flight article assembly. The design also includes mechanical and electronic interfaces to the existing SPHERES hardware, which include self-contained packages that can operate in conjunction with the existing SPHERES electronics

  20. Acquisition of Long-Duration, Low-Gravity Slosh Data Utilizing Existing ISS Equipment (SPHERES) for Calibration of CFD Models of Coupled Fluid-Vehicle Behavior

    NASA Technical Reports Server (NTRS)

    Schallhorn, Paul; Roth, Jacob; Marsell, Brandon; Kirk, Daniel; Gutierrez, Hector; Saenz-Otero, Alvar; Dorney, Daniel; Moder, Jeffrey

    2012-01-01

    a launch vehicle upper stage propellant tank and the maneuvers replicate those of real vehicles. The design includes inertial sensors, data acquisition, image capture and data storage interfaces to the SPHERES VERTIGO computer system on board the flight article assembly. The design also includes mechanical and electronic interfaces to the existing SPHERES hardware, which include self-contained packages that can operate in conjunction with the existing SPHERES electronics.

  1. Evaluation of Mars Entry Reconstructured Trajectories Based on Hypothetical 'Quick-Look' Entry Navigation Data

    NASA Technical Reports Server (NTRS)

    Pastor, P. Rick; Bishop, Robert H.; Striepe, Scott A.

    2000-01-01

    A first order simulation analysis of the navigation accuracy expected from various Navigation Quick-Look data sets is performed. Here quick-look navigation data are observations obtained by hypothetical telemetried data transmitted on the fly during a Mars probe's atmospheric entry. In this simulation study, navigation data consists of 3-axis accelerometer sensor and attitude information data. Three entry vehicle guidance types are studied: I. a Maneuvering entry vehicle (as with Mars 01 guidance where angle of attack and bank angle are controlled); II. Zero angle-of-attack controlled entry vehicle (as with Mars 98); and III. Ballistic, or spin stabilized entry vehicle (as with Mars Pathfinder);. For each type, sensitivity to progressively under sampled navigation data and inclusion of sensor errors are characterized. Attempts to mitigate the reconstructed trajectory errors, including smoothing, interpolation and changing integrator characteristics are also studied.

  2. Numerical Skip-Entry Guidance

    NASA Technical Reports Server (NTRS)

    Tigges, Michael; Crull, Timothy; Rea, Jeremy; Johnson, Wyatt

    2006-01-01

    This paper assesses a preliminary guidance and targeting strategy for accomplishing Skip-Entry (SE) flight during a lunar return-capsule entry flight. One of the primary benefits of flying a SE trajectory is to provide the crew with continuous Continental United States (CONUS) landing site access throughout the lunar month. Without a SE capability, the capsule must land either in water or at one of several distributed land sites in the Southern Hemisphere for a significant portion of a lunar month using a landing and recovery scenario similar to that employed during the Apollo program. With a SE trajectory, the capsule can land either in water at a site in proximity to CONUS or at one of several distributed landing sites within CONUS, thereby simplifying the operational requirements for crew retrieval and vehicle recovery, and possibly enabling a high degree of vehicle reusability. Note that a SE capability does not require that the vehicle land on land. A SE capability enables a longer-range flight than a direct-entry flight, which permits the vehicle to land at a much greater distance from the Entry Interface (EI) point. This does not exclude using this approach to push the landing point to a water location in proximity of CONUS and utilizing water or airborne recovery forces.

  3. 40 CFR 86.606-84 - Entry and access.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Auditing of New Light-Duty Vehicles, Light-Duty Trucks, and Heavy-Duty Vehicles § 86.606-84 Entry and... concerned, operating hours means all times during which personnel other than custodial personnel are at...

  4. 40 CFR 86.606-84 - Entry and access.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Auditing of New Light-Duty Vehicles, Light-Duty Trucks, and Heavy-Duty Vehicles § 86.606-84 Entry and... concerned, operating hours means all times during which personnel other than custodial personnel are at...

  5. Planetary entry vehicle design for planned and potential ESA missions to Titan, Mars, and Earth return (FGE TN 51/92)

    NASA Astrophysics Data System (ADS)

    Smith, Arthur

    1993-04-01

    Design of ballistic planetary entry probes for planned ESA/NASA Titan, Mars, and Earth-Return missions is discussed with emphasis on the common design constraints. The choice of aeroshell configuration and some of the simple design rules are outlined which are used initially at pre-feasibility stages. These include the influence of body dynamics, conventional aerodynamics, and aerothermodynamics. Prediction of the aerothermodynamic environment and influence of uncertainties in the basic physics and chemistry are seen to dominate. Analysis methodology and some of the ESA sponsored experimental program which was initiated to tackle the lack of basic chemistry data is discussed.

  6. 49 CFR Appendix B to Part 591 - Section 591.5(f) Bond for the Entry of More Than a Single Vehicle

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Form HS-7 “Declaration,” WHEREAS, pursuant to 49 CFR part 591, a regulation promulgated under the... Federal motor vehicle safety, or bumper, or theft prevention standards; and WHEREAS, pursuant to 49 CFR..., pursuant to 49 CFR part 593, a regulation promulgated under 49 U.S.C. Chapter 301, the Administrator of...

  7. Planetary entry experiments

    NASA Technical Reports Server (NTRS)

    Craig, Roger A.

    1994-01-01

    The final report summarizes the results from three research areas: (1) window design for the radiometric measurement of the forebody radiative heating experienced by atmospheric entry spaceraft; (2) survey of the current understanding of chemical species on selected solar system bodies and assess the importance of measurements with regard to vehicle environment and with regard to understanding of planetary atmospheres with emphasis on Venus, Mars, and Titan; and (3) measure and analyze the radiation (VUV to near-IR) from the shock heated gas cap of a blunt body in an Ames arc Jet wind-tunnel facility.

  8. Entry Systems Panel

    NASA Technical Reports Server (NTRS)

    Rasky, Daniel J.; Rummler, Donald R.; Bersch, Charlie; Dixon, Sidney C.

    1993-01-01

    As general findings, lessons learned from shuttle are: (1) bridge established between development center (JSC) Research Centers (ARC, LARC), and industry (RI, LMSC, Corning, Mansville, 3M LTV, Union Carbide, Hexcel) for shuttle TPS; (2) not all test results adequately analyzed or in hindsight, completely encompassing all failure modes; (3) gap heating effects from ground facilities not totally indicative of flight experience; (4) need to design with operations in mind (not just to cost) example: moisture intrusion of GR/EP, many other examples; (5) RSI- developed as point design for maneuvering entry vehicle of high L/D; and (6) RSI - 15 years from invention to use on flight hardware.

  9. Preliminary evaluation of the University of South Florida Mobile Data Acquisition System, the Idaho National Engineering Laboratory Versatile Data Acquisition System, and the Autologger Vehicle User Survey System produced by Instrumental Solutions of Ottawa, Canada for the Site Operator Program Field Data Collection

    SciTech Connect

    Kiser, D.M.; Richardson, R.A.

    1993-09-01

    The Electric Vehicle (EV) Site Operator Program, is currently composed of thirteen Site Operators. In addition to operating electric vehicles for demonstration of the technology, the Site Operators also perform operational field testing. Data collected by the programs are input to the Site Operator Database at each site and transmitted, periodically, to the database at the INEL. As the program has expanded, some Site Operators have begun operating vehicles at sites remote from their offices. With the advent of these expanded test programs, it is necessary to consider in-vehicle, automated data acquisition systems. Three of these in-vehicle, data acquisition systems have been designed and constructed: The Mobile Data Acquisition System (MDAS) was designed and constructed by Sigma TecSystems, Inc. located in Tampa, Florida. The Versatile Data Acquisition System (VDAS) was designed and constructed at the INEL under the guidance of the Electric and Hybrid Vehicle (EHV) Program. The AUTOLOGGER Vehicle User Survey System produced by Instrumental Solutions of Ottawa, ON. Because the USF MDAS is a new system proposed for use by the Site Operator Program, the purpose of this report is to provide a preliminary evaluation of the MDAS by comparing the system to the proven VDAS. Data used to perform the comparison was acquired by a review of the MDAS literature provided by the USF, and by a demonstration of the MDAS and its performance, provided by the USF to INEL personnel. A brief discussion of the AUTOLOGGER is also included, for comparison, because it is being used by Southern California Edison (SCE), one of the Site Operator Program participants who recommends the unit as a good system.

  10. Orion Entry Display Feeder and Interactions with the Entry Monitor System

    NASA Technical Reports Server (NTRS)

    Baird, Darren; Bernatovich, Mike; Gillespie, Ellen; Kadwa, Binaifer; Matthews, Dave; Penny, Wes; Zak, Tim; Grant, Mike; Bihari, Brian

    2010-01-01

    The Orion spacecraft is designed to return astronauts to a landing within 10 km of the intended landing target from low Earth orbit, lunar direct-entry, and lunar skip-entry trajectories. Al pile the landing is nominally controlled autonomously, the crew can fly precision entries manually in the event of an anomaly. The onboard entry displays will be used by the crew to monitor and manually fly the entry, descent, and landing, while the Entry Monitor System (EMS) will be used to monitor the health and status of the onboard guidance and the trajectory. The entry displays are driven by the entry display feeder, part of the Entry Monitor System (EMS). The entry re-targeting module, also part of the EMS, provides all the data required to generate the capability footprint of the vehicle at any point in the trajectory, which is shown on the Primary Flight Display (PFD). It also provides caution and warning data and recommends the safest possible re-designated landing site when the nominal landing site is no longer within the capability of the vehicle. The PFD and the EMS allow the crew to manually fly an entry trajectory profile from entry interface until parachute deploy having the flexibility to manually steer the vehicle to a selected landing site that best satisfies the priorities of the crew. The entry display feeder provides data from the ENIS and other components of the GNC flight software to the displays at the proper rate and in the proper units. It also performs calculations that are specific to the entry displays and which are not made in any other component of the flight software. In some instances, it performs calculations identical to those performed by the onboard primary guidance algorithm to protect against a guidance system failure. These functions and the interactions between the entry display feeder and the other components of the EMS are described.

  11. 48 CFR 52.225-8 - Duty-Free Entry.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Director of Customs, please release shipment under 19 CFR part 142 and notify for execution of Customs... 48 Federal Acquisition Regulations System 2 2011-10-01 2011-10-01 false Duty-Free Entry. 52.225-8...-Free Entry. As prescribed in 25.1101(e), insert the following clause: Duty-Free Entry (OCT 2010)...

  12. 48 CFR 52.225-8 - Duty-Free Entry.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Director of Customs, please release shipment under 19 CFR part 142 and notify for execution of Customs... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Duty-Free Entry. 52.225-8...-Free Entry. As prescribed in 25.1101(e), insert the following clause: Duty-Free Entry (OCT 2010)...

  13. 48 CFR 52.225-8 - Duty-Free Entry.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Director of Customs, please release shipment under 19 CFR part 142 and notify for execution of Customs... 48 Federal Acquisition Regulations System 2 2012-10-01 2012-10-01 false Duty-Free Entry. 52.225-8...-Free Entry. As prescribed in 25.1101(e), insert the following clause: Duty-Free Entry (OCT 2010)...

  14. 48 CFR 52.225-8 - Duty-Free Entry.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Director of Customs, please release shipment under 19 CFR part 142 and notify for execution of Customs... 48 Federal Acquisition Regulations System 2 2013-10-01 2013-10-01 false Duty-Free Entry. 52.225-8...-Free Entry. As prescribed in 25.1101(e), insert the following clause: Duty-Free Entry (OCT 2010)...

  15. 48 CFR 52.225-8 - Duty-Free Entry.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Director of Customs, please release shipment under 19 CFR part 142 and notify for execution of Customs... 48 Federal Acquisition Regulations System 2 2014-10-01 2014-10-01 false Duty-Free Entry. 52.225-8...-Free Entry. As prescribed in 25.1101(e), insert the following clause: Duty-Free Entry (OCT 2010)...

  16. 32 CFR 809a.1 - Random installation entry point checks.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Random installation entry point checks. 809a.1... Entry Policy § 809a.1 Random installation entry point checks. The installation commander determines when, where, and how to implement random checks of vehicles or pedestrians. The commander conducts...

  17. Mars Science Laboratory Entry Guidance

    NASA Technical Reports Server (NTRS)

    Mendeck, Gavin F.

    2011-01-01

    The Mars Science Laboratory will be the first Mars mission to attempt a guided entry with the objective of safely delivering the entry vehicle to a survivable parachute deploy state within 12.5 km of the pre-designated parachute deploy coordinates. The Entry Terminal Point Controller guidance algorithm is derived from the final phase Apollo Command Module guidance and, like Apollo, modulates the bank angle to control range based on deviations in range, altitude rate, and drag acceleration from a reference trajectory. For application to Mars landers which must make use of the tenuous Martian atmosphere, it is critical to balance the lift of the vehicle to minimize the range while still ensuring a safe deploy altitude. An overview of the process to generate optimized guidance settings is presented, discussing improvements made over the last nine years. Performance tradeoffs between ellipse size and deploy altitude will be presented, along with imposed constraints of entry acceleration and heating. Performance sensitivities to the bank reversal deadbands, heading alignment, attitude initialization error, and entry delivery errors are presented.

  18. Advances in spacecraft atmospheric entry guidance

    NASA Astrophysics Data System (ADS)

    Benito Manrique, Joel

    In order to advance entry guidance technology two different research areas have been explored with the objective of increasing the reachable landing area and the landing accuracy for future Mars missions. Currently only the northern hemisphere of Mars is available for landing due to its low elevation. Only low elevation landing sites have the necessary atmospheric density to allow landing using current Entry, Descent and Landing (EDL) technology. In order to reach most of the Ancient Highlands, the majority of the southern hemisphere, advanced EDL technology is needed in multiple fields, including entry guidance. The first research area is the definition and applications of reachable and controllable sets for entry. The definition of the reachable and controllable sets provides a framework for the study of the capabilities of an entry vehicle in a given planet. Reachable and controllable sets can be used to comprehensively characterize the envelope of trajectories that a vehicle can fly, the sites it can reach and the entry states that can be accommodated. The sets can also be used for the evaluation of trajectory planning algorithms and to assist in the selection of the entry or landing sites. In essence, the reachable and controllable sets offer a powerful vehicle and trajectory analysis and design framework that allows for better mission design choices. In order to illustrate the use of the sets, they are computed for a representative Mars mission using two different vehicle configurations. The sets characterize the impact of the vehicle configuration on the entry capability. Furthermore, the sets are used to find the best skip-entry trajectory for a return from the Moon mission, highlighting the utility of the sets in atmospheric maneuvers other than entry. The second research area is the development of the components of an entry guidance algorithm that allow high elevation landing and provide as well high landing accuracy. The approach taken follows the

  19. Radar cross section measurements of a scale model of the space shuttle orbiter vehicle

    NASA Technical Reports Server (NTRS)

    Yates, W. T.

    1978-01-01

    A series of microwave measurements was conducted to determine the radar cross section of the Space Shuttle Orbiter vehicle at a frequency and at aspect angles applicable to re-entry radar acquisition and tracking. The measurements were performed in a microwave anechoic chamber using a 1/15th scale model and a frequency applicable to C-band tracking radars. The data were digitally recorded and processed to yield statistical descriptions useful for prediction of orbiter re-entry detection and tracking ranges.

  20. Application of the FADS system on the Re-entry Module

    NASA Astrophysics Data System (ADS)

    Zhen, Huang

    2016-07-01

    The aerodynamic model for Flush Air Data Sensing System (FADS) is built based on the surface pressure distribution obtained through the pressure orifices laid on specific positions of the surface,and the flight parameters,such as angle of attack,angle of side-slip,Mach number,free-stream static pressure and dynamic pressure are inferred from the aerodynamic model.The flush air data sensing system (FADS) has been used on several flight tests of aircraft and re-entry vehicle,such as,X-15,space shuttle,F-14,X-33,X-43A and so on. This paper discusses the application of the FADS on the re-entry module with blunt body to obtain high-precision aerodynamic parameters.First of all,a basic theory and operating principle of the FADS is shown.Then,the applications of the FADS on typical aircrafts and re-entry vehicles are described.Thirdly,the application mode on the re-entry module with blunt body is discussed in detail,including aerodynamic simulation,pressure distribution,trajectory reconstruction and the hardware shoule be used,such as flush air data sensing system(FADS),inertial navigation system (INS),data acquisition system,data storage system.Finally,ablunt module re-entry flight test from low earth orbit (LEO) is planned to obtain aerodynamic parameters and amend the aerodynamic model with this FADS system data.The results show that FADS system can be applied widely in re-entry module with blunt bodies.

  1. Atlas F entry aerothermic study

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The feasibility of obtaining heat transfer data on an expended Atlas F booster launch vehicle was investigated in the altitude range of 300,000 to 200,000 feet during entry conditions, with a velocity in the range of 20,000 to 25,000 feet per second, and through a range of vehicle attitudes of plus or minus 90 degrees. These data are desired for correlation with turbulent heat transfer and boundary layer transition data obtained from wind tunnel test facilities. The data would also be valuable in assessing rarified gas and surface catalicity effects in a real gas environment.

  2. Orion Entry Handling Qualities Assessments

    NASA Technical Reports Server (NTRS)

    Bihari, B.; Tiggers, M.; Strahan, A.; Gonzalez, R.; Sullivan, K.; Stephens, J. P.; Hart, J.; Law, H., III; Bilimoria, K.; Bailey, R.

    2011-01-01

    The Orion Command Module (CM) is a capsule designed to bring crew back from the International Space Station (ISS), the moon and beyond. The atmospheric entry portion of the flight is deigned to be flown in autopilot mode for nominal situations. However, there exists the possibility for the crew to take over manual control in off-nominal situations. In these instances, the spacecraft must meet specific handling qualities criteria. To address these criteria two separate assessments of the Orion CM s entry Handling Qualities (HQ) were conducted at NASA s Johnson Space Center (JSC) using the Cooper-Harper scale (Cooper & Harper, 1969). These assessments were conducted in the summers of 2008 and 2010 using the Advanced NASA Technology Architecture for Exploration Studies (ANTARES) six degree of freedom, high fidelity Guidance, Navigation, and Control (GN&C) simulation. This paper will address the specifics of the handling qualities criteria, the vehicle configuration, the scenarios flown, the simulation background and setup, crew interfaces and displays, piloting techniques, ratings and crew comments, pre- and post-fight briefings, lessons learned and changes made to improve the overall system performance. The data collection tools, methods, data reduction and output reports will also be discussed. The objective of the 2008 entry HQ assessment was to evaluate the handling qualities of the CM during a lunar skip return. A lunar skip entry case was selected because it was considered the most demanding of all bank control scenarios. Even though skip entry is not planned to be flown manually, it was hypothesized that if a pilot could fly the harder skip entry case, then they could also fly a simpler loads managed or ballistic (constant bank rate command) entry scenario. In addition, with the evaluation set-up of multiple tasks within the entry case, handling qualities ratings collected in the evaluation could be used to assess other scenarios such as the constant bank angle

  3. Small multipurpose stored data acquisition system

    SciTech Connect

    Hauser, G.C.; Ryerson, D.E.

    1990-01-01

    Sandia National Laboratories Telemetry Department has designed and is fielding a small, inexpensive multipurpose stored data acquisition system in tests ranging from 6000 meters below the ocean surface in seafloor penetrators to 40,000 meters above sea level in gamma ray telescope balloons. The systems consists of a simple microprocessor-controlled unit which digitizes analog data stores the data in memory for readout after the test by a portable personal compute. The system has been used in over ninety tests consisting of parachute drops, water entry test, vehicle environmental monitoring, and seafloor penetration tests. Data typically recorded with the system are acceleration, strain, temperature, pressure, and angular velocity. The system is also capable of generating control functions such as parachute release. 5 refs., 6 figs.

  4. 48 CFR 908.7101 - Motor vehicles.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Motor vehicles. 908.7101 Section 908.7101 Federal Acquisition Regulations System DEPARTMENT OF ENERGY COMPETITION ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Acquisition of Special Items 908.7101 Motor vehicles....

  5. 48 CFR 908.7101 - Motor vehicles.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Motor vehicles. 908.7101 Section 908.7101 Federal Acquisition Regulations System DEPARTMENT OF ENERGY COMPETITION ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Acquisition of Special Items 908.7101 Motor vehicles....

  6. 48 CFR 908.7101 - Motor vehicles.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Motor vehicles. 908.7101 Section 908.7101 Federal Acquisition Regulations System DEPARTMENT OF ENERGY COMPETITION ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Acquisition of Special Items 908.7101 Motor vehicles....

  7. 48 CFR 908.7101 - Motor vehicles.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Motor vehicles. 908.7101 Section 908.7101 Federal Acquisition Regulations System DEPARTMENT OF ENERGY COMPETITION ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Acquisition of Special Items 908.7101 Motor vehicles....

  8. 48 CFR 908.7101 - Motor vehicles.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Motor vehicles. 908.7101 Section 908.7101 Federal Acquisition Regulations System DEPARTMENT OF ENERGY COMPETITION ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Acquisition of Special Items 908.7101 Motor vehicles....

  9. 10 CFR 490.305 - Acquisitions satisfying the mandate.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ....305 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Fuel Provider Vehicle Acquisition Mandate § 490.305 Acquisitions satisfying the mandate. The... light duty vehicle (regardless of the model year of manufacture), capable of operating on...

  10. 10 CFR 490.305 - Acquisitions satisfying the mandate.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ....305 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Fuel Provider Vehicle Acquisition Mandate § 490.305 Acquisitions satisfying the mandate. The... light duty vehicle (regardless of the model year of manufacture), capable of operating on...

  11. 10 CFR 490.305 - Acquisitions satisfying the mandate.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ....305 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Fuel Provider Vehicle Acquisition Mandate § 490.305 Acquisitions satisfying the mandate. The... light duty vehicle (regardless of the model year of manufacture), capable of operating on...

  12. 10 CFR 490.305 - Acquisitions satisfying the mandate.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ....305 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Fuel Provider Vehicle Acquisition Mandate § 490.305 Acquisitions satisfying the mandate. The... light duty vehicle (regardless of the model year of manufacture), capable of operating on...

  13. 10 CFR 490.305 - Acquisitions satisfying the mandate.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ....305 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Fuel Provider Vehicle Acquisition Mandate § 490.305 Acquisitions satisfying the mandate. The... light duty vehicle (regardless of the model year of manufacture), capable of operating on...

  14. 48 CFR 908.7101-3 - Direct acquisition.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Direct acquisition. 908.7101-3 Section 908.7101-3 Federal Acquisition Regulations System DEPARTMENT OF ENERGY COMPETITION ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Acquisition of Special Items 908.7101-3 Direct acquisition. Vehicles may be acquired by...

  15. A new Green's function Monte Carlo algorithm for the solution of the two-dimensional nonlinear Poisson-Boltzmann equation: Application to the modeling of the communication breakdown problem in space vehicles during re-entry

    NASA Astrophysics Data System (ADS)

    Chatterjee, Kausik; Roadcap, John R.; Singh, Surendra

    2014-11-01

    The objective of this paper is the exposition of a recently-developed, novel Green's function Monte Carlo (GFMC) algorithm for the solution of nonlinear partial differential equations and its application to the modeling of the plasma sheath region around a cylindrical conducting object, carrying a potential and moving at low speeds through an otherwise neutral medium. The plasma sheath is modeled in equilibrium through the GFMC solution of the nonlinear Poisson-Boltzmann (NPB) equation. The traditional Monte Carlo based approaches for the solution of nonlinear equations are iterative in nature, involving branching stochastic processes which are used to calculate linear functionals of the solution of nonlinear integral equations. Over the last several years, one of the authors of this paper, K. Chatterjee has been developing a philosophically-different approach, where the linearization of the equation of interest is not required and hence there is no need for iteration and the simulation of branching processes. Instead, an approximate expression for the Green's function is obtained using perturbation theory, which is used to formulate the random walk equations within the problem sub-domains where the random walker makes its walks. However, as a trade-off, the dimensions of these sub-domains have to be restricted by the limitations imposed by perturbation theory. The greatest advantage of this approach is the ease and simplicity of parallelization stemming from the lack of the need for iteration, as a result of which the parallelization procedure is identical to the parallelization procedure for the GFMC solution of a linear problem. The application area of interest is in the modeling of the communication breakdown problem during a space vehicle's re-entry into the atmosphere. However, additional application areas are being explored in the modeling of electromagnetic propagation through the atmosphere/ionosphere in UHF/GPS applications.

  16. A new Green's function Monte Carlo algorithm for the solution of the two-dimensional nonlinear Poisson–Boltzmann equation: Application to the modeling of the communication breakdown problem in space vehicles during re-entry

    SciTech Connect

    Chatterjee, Kausik; Roadcap, John R.; Singh, Surendra

    2014-11-01

    The objective of this paper is the exposition of a recently-developed, novel Green's function Monte Carlo (GFMC) algorithm for the solution of nonlinear partial differential equations and its application to the modeling of the plasma sheath region around a cylindrical conducting object, carrying a potential and moving at low speeds through an otherwise neutral medium. The plasma sheath is modeled in equilibrium through the GFMC solution of the nonlinear Poisson–Boltzmann (NPB) equation. The traditional Monte Carlo based approaches for the solution of nonlinear equations are iterative in nature, involving branching stochastic processes which are used to calculate linear functionals of the solution of nonlinear integral equations. Over the last several years, one of the authors of this paper, K. Chatterjee has been developing a philosophically-different approach, where the linearization of the equation of interest is not required and hence there is no need for iteration and the simulation of branching processes. Instead, an approximate expression for the Green's function is obtained using perturbation theory, which is used to formulate the random walk equations within the problem sub-domains where the random walker makes its walks. However, as a trade-off, the dimensions of these sub-domains have to be restricted by the limitations imposed by perturbation theory. The greatest advantage of this approach is the ease and simplicity of parallelization stemming from the lack of the need for iteration, as a result of which the parallelization procedure is identical to the parallelization procedure for the GFMC solution of a linear problem. The application area of interest is in the modeling of the communication breakdown problem during a space vehicle's re-entry into the atmosphere. However, additional application areas are being explored in the modeling of electromagnetic propagation through the atmosphere/ionosphere in UHF/GPS applications.

  17. Texting while driving: is speech-based text entry less risky than handheld text entry?

    PubMed

    He, J; Chaparro, A; Nguyen, B; Burge, R J; Crandall, J; Chaparro, B; Ni, R; Cao, S

    2014-11-01

    Research indicates that using a cell phone to talk or text while maneuvering a vehicle impairs driving performance. However, few published studies directly compare the distracting effects of texting using a hands-free (i.e., speech-based interface) versus handheld cell phone, which is an important issue for legislation, automotive interface design and driving safety training. This study compared the effect of speech-based versus handheld text entries on simulated driving performance by asking participants to perform a car following task while controlling the duration of a secondary text-entry task. Results showed that both speech-based and handheld text entries impaired driving performance relative to the drive-only condition by causing more variation in speed and lane position. Handheld text entry also increased the brake response time and increased variation in headway distance. Text entry using a speech-based cell phone was less detrimental to driving performance than handheld text entry. Nevertheless, the speech-based text entry task still significantly impaired driving compared to the drive-only condition. These results suggest that speech-based text entry disrupts driving, but reduces the level of performance interference compared to text entry with a handheld device. In addition, the difference in the distraction effect caused by speech-based and handheld text entry is not simply due to the difference in task duration. PMID:25089769

  18. 48 CFR 252.225-7013 - Duty-free entry.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... CFR part 142 and notify Commander, Defense Contract Management Agency (DCMA) New York, ATTN: Customs... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false Duty-free entry. 252.225... Clauses 252.225-7013 Duty-free entry. As prescribed in 225.1101(4), use the following clause:...

  19. 48 CFR 252.225-7013 - Duty-free entry.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... shipment under 19 CFR part 142 and notify Commander, Defense Contract Management Agency (DCMA) New York... 48 Federal Acquisition Regulations System 3 2011-10-01 2011-10-01 false Duty-free entry. 252.225... Clauses 252.225-7013 Duty-free entry. As prescribed in 225.1101(4), use the following clause:...

  20. 48 CFR 252.225-7013 - Duty-free entry.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... shipment under 19 CFR part 142 and notify Commander, Defense Contract Management Agency (DCMA) New York... 48 Federal Acquisition Regulations System 3 2012-10-01 2012-10-01 false Duty-free entry. 252.225... Clauses 252.225-7013 Duty-free entry. As prescribed in 225.1101(4), use the following clause:...

  1. 48 CFR 252.225-7013 - Duty-free entry.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... shipment under 19 CFR part 142 and notify Commander, Defense Contract Management Agency (DCMA) New York... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Duty-free entry. 252.225... Clauses 252.225-7013 Duty-free entry. As prescribed in 225.1101(4), use the following clause:...

  2. 48 CFR 252.225-7013 - Duty-free entry.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... shipment under 19 CFR part 142 and notify Commander, Defense Contract Management Agency (DCMA) New York... 48 Federal Acquisition Regulations System 3 2013-10-01 2013-10-01 false Duty-free entry. 252.225... Clauses 252.225-7013 Duty-free entry. As prescribed in 225.1101(4), use the following clause:...

  3. Aerodynamics of the Mars Microprobe Entry Vehicles

    NASA Technical Reports Server (NTRS)

    Mitcheltree, R. A.; Moss, J. N.; Cheatwood, F. M.; Greene, F. A.; Braun, R. D.

    1997-01-01

    The selection of the unique aeroshell shape for the Mars Microprobes is discussed. A description of its aerodynamics in hypersonic rarefied, hypersonic continuum, supersonic and transonic flow regimes is then presented. This description is based on Direct Simulation Monte Carlo analyses in the rarefied-flow regime, thermochemical nonequilibrium Computational Fluid Dynamics in the hypersonic regime, existing wind tunnel data in the supersonic and transonic regime, additional computational work in the transonic regime, and finally, ballistic range data. The aeroshell is shown to possess the correct combination of aerodynamic stability and drag to convert the probe's initial tumbling attitude and high velocity at atmospheric-interface into the desired surface-impact orientation and velocity.

  4. Passive Earth Entry Vehicle Energy Absorbing Systems

    NASA Astrophysics Data System (ADS)

    Kellas, S.; Maddock, R. W.

    2014-06-01

    A critical element of a passive EEV performance is the energy absorbing system required to attenuate the dynamic landing loads. Two design approaches are described and the pros and cons based on particular mission requirements are discussed.

  5. Human target acquisition performance

    NASA Astrophysics Data System (ADS)

    Teaney, Brian P.; Du Bosq, Todd W.; Reynolds, Joseph P.; Thompson, Roger; Aghera, Sameer; Moyer, Steven K.; Flug, Eric; Espinola, Richard; Hixson, Jonathan

    2012-06-01

    The battlefield has shifted from armored vehicles to armed insurgents. Target acquisition (identification, recognition, and detection) range performance involving humans as targets is vital for modern warfare. The acquisition and neutralization of armed insurgents while at the same time minimizing fratricide and civilian casualties is a mounting concern. U.S. Army RDECOM CERDEC NVESD has conducted many experiments involving human targets for infrared and reflective band sensors. The target sets include human activities, hand-held objects, uniforms & armament, and other tactically relevant targets. This paper will define a set of standard task difficulty values for identification and recognition associated with human target acquisition performance.

  6. Radiative Heat Transfer During Atmosphere Entry at Parabolic Velocity

    NASA Technical Reports Server (NTRS)

    Yoshikawa, Kenneth K.; Wick, Bradford H.

    1961-01-01

    Stagnation point radiative heating rates for manned vehicles entering the earth's atmosphere at parabolic velocity are presented and compared with corresponding laminar convective heating rates. The calculations were made for both nonlifting and lifting entry trajectories for vehicles of varying nose radius, weight-to-area ratio, and drag. It is concluded from the results presented that radiative heating will be important for the entry conditions considered.

  7. Shuttle entry technology payloads. [for aerothermodynamic research

    NASA Technical Reports Server (NTRS)

    Siemers, P. M., III

    1975-01-01

    The flight frequency of the Space Transportation System (STS) coupled with its large payload-carrying capability will provide an unprecedented opportunity for conducting aerothermodynamic/entry technology research. This STS research opportunity can be characterized into two distinct categories: (1) that research which will utilize the STS orbiter as the test vehicle, and (2) that research which will utilize a vehicle launched from the orbiter for entry. To date, on-going studies have defined experiments as well as the support systems required for the shuttle launched research program. The proposed Entry Technology Program will provide a flight data base from which accurate correlations can be performed relative to ground test and analysis data. These correlations will result in optimized designs for future flight systems.

  8. Atmospheric Entry Experiments at IRS

    NASA Astrophysics Data System (ADS)

    Auweter-Kurtz, M.; Endlich, P.; Herdrich, G.; Kurtz, H.; Laux, T.; Löhle, S.; Nazina, N.; Pidan, S.

    2002-01-01

    Entering the atmosphere of celestial bodies, spacecrafts encounter gases at velocities of several km/s, thereby being subjected to great heat loads. The thermal protection systems and the environment (plasma) have to be investigated by means of computational and ground facility based simulations. For more than a decade, plasma wind tunnels at IRS have been used for the investigation of TPS materials. Nevertheless, ground tests and computer simulations cannot re- place space flights completely. Particularly, entry mission phases encounter challenging problems, such as hypersonic aerothermodynamics. Concerning the TPS, radiation-cooled materials used for reuseable spacecrafts and ablator tech- nologies are of importance. Besides the mentioned technologies, there is the goal to manage guidance navigation, con- trol, landing technology and inflatable technologies such as ballutes that aim to keep vehicles in the atmosphere without landing. The requirement to save mass and energy for planned interplanetary missions such as Mars Society Balloon Mission, Mars Sample Return Mission, Mars Express or Venus Sample Return mission led to the need for manoeuvres like aerocapture, aero-breaking and hyperbolic entries. All three are characterized by very high kinetic vehicle energies to be dissipated by the manoeuvre. In this field flight data are rare. The importance of these manoeuvres and the need to increase the knowledge of required TPS designs and behavior during such mission phases point out the need of flight experiments. As result of the experience within the plasma diagnostic tool development and the plasma wind tunnel data base, flight experiments like the PYrometric RE-entry EXperiment PYREX were developed, fully qualified and successfully flown. Flight experiments such as the entry spectrometer RESPECT and PYREX on HOPE-X are in the conceptual phase. To increase knowledge in the scope of atmospheric manoeuvres and entries, data bases have to be created combining both

  9. Evolved Acceleration Guidance for Planetary Entry

    NASA Astrophysics Data System (ADS)

    Mease, K. D.; Leavitt, J. A.; Ferch, M.

    The U.S. Apollo and Shuttle programs have proven the viability and effectiveness of acceleration guidance. New capabilities have been developed to augment this basic concept. Algorithms have been designed for low lift to drag ratio vehicles and for mid to high lift to drag ratio vehicles. These algorithms have been tested for Mars landing and for earth entry of reusable launch vehicles and have performed well in both cases. Also the trajectory planner has been incorporated into a landing footprint generator that is designed for on-board use.

  10. Generic aerocapture atmospheric entry study, volume 1

    NASA Technical Reports Server (NTRS)

    1980-01-01

    An atmospheric entry study to fine a generic aerocapture vehicle capable of missions to Mars, Saturn, and Uranus is reported. A single external geometry was developed through atmospheric entry simulations. Aerocapture is a system design concept which uses an aerodynamically controlled atmospheric entry to provide the necessary velocity depletion to capture payloads into planetary orbit. Design concepts are presented which provide the control accuracy required while giving thermal protection for the mission payload. The system design concepts consist of the following elements: (1) an extendable biconic aerodynamic configuration with lift to drag ratio between 1.0 and 2.0; (2) roll control system concepts to control aerodynamic lift and disturbance torques; (3) aeroshell design concepts capable of meeting dynamic pressure loads during aerocapture; and (4) entry thermal protection system design concepts to meet thermodynamic loads during aerocapture.

  11. Technology for Entry Probes

    NASA Technical Reports Server (NTRS)

    Cutts, James A.; Arnold, James; Venkatapathy, Ethiraj; Kolawa, Elizabeth; Munk, Michelle; Wercinski, Paul; Laub, Bernard

    2005-01-01

    A viewgraph describing technologies for entry probes is presented. The topics include: 1) Entry Phase; 2) Descent Phase; 3) Long duration atmospheric observations; 4) Survivability at high temperatures; and 5) Summary.

  12. A Comparison of Two Skip Entry Guidance Algorithms

    NASA Technical Reports Server (NTRS)

    Rea, Jeremy R.; Putnam, Zachary R.

    2007-01-01

    The Orion capsule vehicle will have a Lift-to-Drag ratio (L/D) of 0.3-0.35. For an Apollo-like direct entry into the Earth's atmosphere from a lunar return trajectory, this L/D will give the vehicle a maximum range of about 2500 nm and a maximum crossrange of 216 nm. In order to y longer ranges, the vehicle lift must be used to loft the trajectory such that the aerodynamic forces are decreased. A Skip-Trajectory results if the vehicle leaves the sensible atmosphere and a second entry occurs downrange of the atmospheric exit point. The Orion capsule is required to have landing site access (either on land or in water) inside the Continental United States (CONUS) for lunar returns anytime during the lunar month. This requirement means the vehicle must be capable of flying ranges of at least 5500 nm. For the L/D of the vehicle, this is only possible with the use of a guided Skip-Trajectory. A skip entry guidance algorithm is necessary to achieve this requirement. Two skip entry guidance algorithms have been developed: the Numerical Skip Entry Guidance (NSEG) algorithm was developed at NASA/JSC and PredGuid was developed at Draper Laboratory. A comparison of these two algorithms will be presented in this paper. Each algorithm has been implemented in a high-fidelity, 6 degree-of-freedom simulation called the Advanced NASA Technology Architecture for Exploration Studies (ANTARES). NASA and Draper engineers have completed several monte carlo analyses in order to compare the performance of each algorithm in various stress states. Each algorithm has been tested for entry-to-target ranges to include direct entries and skip entries of varying length. Dispersions have been included on the initial entry interface state, vehicle mass properties, vehicle aerodynamics, atmosphere, and Reaction Control System (RCS). Performance criteria include miss distance to the target, RCS fuel usage, maximum g-loads and heat rates for the first and second entry, total heat load, and control

  13. Space shuttle GN and C equation document: Entry and transition guidance

    NASA Technical Reports Server (NTRS)

    Marcus, F. J.

    1973-01-01

    The entry-guidance routine presented is designed to take the orbiter vehicle from entry interface through the critical heating phase of entry down to the start of the approach phase. The material includes: (1) a functional flow diagram, (2) input and output variables, (3) a description of equations, and (4) detailed flow diagrams.

  14. Acquisition signal transmitter

    NASA Technical Reports Server (NTRS)

    Friedman, Morton L. (Inventor)

    1989-01-01

    An encoded information transmitter which transmits a radio frequency carrier that is amplitude modulated by a constant frequency waveform and thereafter amplitude modulated by a predetermined encoded waveform, the constant frequency waveform modulated carrier constituting an acquisition signal and the encoded waveform modulated carrier constituting an information bearing signal, the acquisition signal providing enhanced signal acquisition and interference rejection favoring the information bearing signal. One specific application for this transmitter is as a distress transmitter where a conventional, legislated audio tone modulated signal is transmitted followed first by the acquisition signal and then the information bearing signal, the information bearing signal being encoded with, among other things, vehicle identification data. The acquistion signal enables a receiver to acquire the information bearing signal where the received signal is low and/or where the received signal has a low signal-to-noise ratio in an environment where there are multiple signals in the same frequency band as the information bearing signal.

  15. Orion Capsule Handling Qualities for Atmospheric Entry

    NASA Technical Reports Server (NTRS)

    Tigges, Michael A.; Bihari, Brian D.; Stephens, John-Paul; Vos, Gordon A.; Bilimoria, Karl D.; Mueller, Eric R.; Law, Howard G.; Johnson, Wyatt; Bailey, Randall E.; Jackson, Bruce

    2011-01-01

    Two piloted simulations were conducted at NASA's Johnson Space Center using the Cooper-Harper scale to study the handling qualities of the Orion Command Module capsule during atmospheric entry flight. The simulations were conducted using high fidelity 6-DOF simulators for Lunar Return Skip Entry and International Space Station Return Direct Entry flight using bank angle steering commands generated by either the Primary (PredGuid) or Backup (PLM) guidance algorithms. For both evaluations, manual control of bank angle began after descending through Entry Interface into the atmosphere until drogue chutes deployment. Pilots were able to use defined bank management and reversal criteria to accurately track the bank angle commands, and stay within flight performance metrics of landing accuracy, g-loads, and propellant consumption, suggesting that the pilotability of Orion under manual control is both achievable and provides adequate trajectory performance with acceptable levels of pilot effort. Another significant result of these analyses is the applicability of flying a complex entry task under high speed entry flight conditions relevant to the next generation Multi Purpose Crew Vehicle return from Mars and Near Earth Objects.

  16. Space vehicle gyroscope sensor applications

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Considerations which form the basis for the specification, design and evaluation of gyroscopes for spaceborne sensor applications are presented. The applications are distinguished by basic vehicle category: launch vehicles, spacecraft, entry vehicles and sounding rockets. Specifically excluded from discussion are gyroscope effector applications. Exotic or unconventional gyroscopes for which operational experience is nonexistent are mentioned only briefly to alert the reader of future trends. General requirements for testing and evaluation are discussed.

  17. 48 CFR 908.7101-5 - Used vehicles.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Used vehicles. 908.7101-5 Section 908.7101-5 Federal Acquisition Regulations System DEPARTMENT OF ENERGY COMPETITION ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Acquisition of Special Items 908.7101-5 Used vehicles. Normally, DOE does not purchase...

  18. 48 CFR 945.570-8 - Reporting motor vehicle data.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Reporting motor vehicle... Reporting motor vehicle data. (a) Contractors conducting motor vehicle operations shall forward annually (on or before December 1) to the contracting officer their plan for acquisition of motor vehicles for...

  19. 48 CFR 908.1102-70 - Vehicle leasing.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Vehicle leasing. 908.1102... ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Leasing of Motor Vehicles 908.1102-70 Vehicle leasing. (a)(4) Commercial vehicle lease sources may be used only when the General Services...

  20. Stardust Entry Reconstruction

    NASA Technical Reports Server (NTRS)

    Desai, Prasun N.; Qualls, Garry D.

    2008-01-01

    An overview of the reconstruction analyses performed for the Stardust capsule entry is described. The results indicate that the actual entry was very close to the pre-entry predictions. The capsule landed 8.1 km north-northwest of the desired target at Utah Test and Training Range. Analyses of infrared video footage and radar range data (obtained from tracking stations) during the descent show that drogue parachute deployment was 4.8 s later than the pre-entry prediction, while main parachute deployment was 19.3 s earlier than the pre-set timer indicating that main deployment was actually triggered by the backup baroswitch. Reconstruction of a best estimated trajectory revealed that the aerodynamic drag experienced by the capsule during hypersonic flight was within 1% of pre-entry predications. Observations of the heatshield support the pre-entry estimates of small hypersonic angles of attack, since there was very little, if any, charring of the shoulder region or the aftbody. Through this investigation, an overall assertion can be made that all the data gathered from the Stardust capsule entry were consistent with flight performance close to nominal pre-entry predictions. Consequently, the design principles and methodologies utilized for the flight dynamics, aerodynamics, and aerothermodynamics analyses have been corroborated.

  1. Entry Skills for BSNs.

    ERIC Educational Resources Information Center

    Stull, Mary K.

    1986-01-01

    Describes the Continuing Education for Consensus on Entry Skills project, designed to bring the expectations of nursing service and nursing education closer on entry-level competencies of new baccalaureate graduates. Discusses teaching and collaboration skills, planning and evaluation of patient care skills, interpersonal relations/communication…

  2. Co-Optimization of Blunt Body Shapes for Moving Vehicles

    NASA Technical Reports Server (NTRS)

    Brown, James L. (Inventor); Garcia, Joseph A (Inventor); Kinney, David J. (Inventor); Bowles, Jeffrey V (Inventor); Mansour, Nagi N (Inventor)

    2014-01-01

    A method and associated system for multi-disciplinary optimization of various parameters associated with a space vehicle that experiences aerocapture and atmospheric entry in a specified atmosphere. In one embodiment, simultaneous maximization of a ratio of landed payload to vehicle atmospheric entry mass, maximization of fluid flow distance before flow separation from vehicle, and minimization of heat transfer to the vehicle are performed with respect to vehicle surface geometric parameters, and aerostructure and aerothermal vehicle response for the vehicle moving along a specified trajectory. A Pareto Optimal set of superior performance parameters is identified.

  3. Launch, Entry and Abort, Intravehicular Spacesuits

    NASA Technical Reports Server (NTRS)

    Thomas, Kenneth S.

    2010-01-01

    Senior spacesuit expert, will present information about Launch, Entry and Abort (LEA) spacesuits - part of an overall vehicle crew escape and survival system. These LEA spacesuits are worn during the launch and reentry to enhance crew survival. The U.S. has traditionally called these spacesuits Intravehicular Activity (IVA) spacesuits. The Russians refer to this type of spacesuit as "Rescue Suits." Thomas will discuss the success of the LEA suits and the consequences of eliminating their use or providing inadequate systems.

  4. Entry, Descent, and Landing Communications for the 2011 Mars Science Laboratory

    NASA Technical Reports Server (NTRS)

    Abilleira, Fernando; Shidner, Jeremy D.

    2012-01-01

    The Mars Science Laboratory (MSL), established as the most advanced rover to land on the surface of Mars to date, launched on November 26th, 2011 and arrived to the Martian Gale Crater during the night of August 5th, 2012 (PDT). MSL will investigate whether the landing region was ever suitable to support carbon-based life, and examine rocks, soil, and the atmosphere with a sophisticated suite of tools. This paper addresses the flight system requirement by which the vehicle transmitted indications of the following events using both X-band tones and UHF telemetry to allow identification of probable root causes should a mission anomaly have occurred: Heat-Rejection System (HRS) venting, completion of the cruise stage separation, turn to entry attitude, atmospheric deceleration, bank angle reversal commanded, parachute deployment, heatshield separation, radar ground acquisition, powered descent initiation, rover separation from the descent stage, and rover release. During Entry, Descent, and Landing (EDL), the flight system transmitted a UHF telemetry stream adequate to determine the state of the spacecraft (including the presence of faults) at 8 kbps initiating from cruise stage separation through at least one minute after positive indication of rover release on the surface of Mars. The flight system also transmitted X-band semaphore tones from Entry to Landing plus one minute although since MSL was occulted, as predicted, by Mars as seen from the Earth, Direct-To-Earth (DTE) communications were interrupted at approximately is approx. 5 min after Entry ( approximately 130 prior to Landing). The primary data return paths were through the Deep Space Network (DSN) for DTE and the existing Mars network of orbiting assets for UHF, which included the Mars Reconnaissance Orbiter (MRO), Mars Odyssey (ODY), and Mars Express (MEX) elements. These orbiters recorded the telemetry data stream and returned it back to Earth via the DSN. The paper also discusses the total power

  5. 40 CFR 600.005-81 - Maintenance of records and rights of entry.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... and rights of entry. The provisions of this section are applicable to all fuel economy data vehicles. Certification vehicles are required to meet the provisions of 40 CFR 86.000-7 or 40 CFR 86.1844-01, as... (CONTINUED) ENERGY POLICY FUEL ECONOMY AND CARBON-RELATED EXHAUST EMISSIONS OF MOTOR VEHICLES Fuel...

  6. The Mars Phoenix Communications Brownout during Entry into the Martian Atmosphere

    NASA Astrophysics Data System (ADS)

    Morabito, D.; Kornfeld, R.; Bruvold, K.; Craig, L.; Edquist, K.

    2009-11-01

    Propagation of radio signals through sufficiently dense plasma will become disrupted during a space vehicle's hypersonic entry phase into a planetary atmosphere. The Mars Phoenix communication links were found to experience varying levels of reduced received signal strength (brownout) during the spacecraft's entry into the Martian atmosphere on May 25, 2008. These fades were attributed to charged particles generated inside the entry vehicle's high-temperature shock layer during the hypersonic entry. This article presents the results of the analysis of the UHF carrier signal power emitted by Phoenix as received by three orbiting relay satellites during the period around peak heating: Mars Reconnaissance Orbiter, Mars Odyssey, and Mars Express.

  7. Entry Attitude Controller for the Mars Science Laboratory

    NASA Technical Reports Server (NTRS)

    Brugarolas, Paul B.; SanMartin, A. Miguel; Wong, Edward C.

    2007-01-01

    This paper describes the preliminary concept for the RCS 3-axis attitude controller for the exo-atmospheric and guided entry phases of the Mars Science Laboratory Entry, Descend and Landing. The entry controller is formulated as three independent channels in the control frame, which is nominally aligned with the stability frame. Each channel has a feedfoward and a feedback. The feedforward path enables fast response to large bank commands. The feedback path stabilizes the vehicle angle of attack and sideslip around its trim position, and tracks bank commands. The feedback path has a PD/D structure with deadbands that minimizes fuel usage. The performance of this design is demonstrated via simulation.

  8. 5. PORTICO AND ENTRY DETAIL, SOUTH (FRONT) ELEVATION. This entry ...

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

    5. PORTICO AND ENTRY DETAIL, SOUTH (FRONT) ELEVATION. This entry replaces original twin entries to southeast and southwest rooms from portico, and was installed when south entry hall was built. - Oak Island (House), County Road 768 vicinity, Edisto Island, Charleston County, SC

  9. Angle of Attack Modulation for Mars Entry Terminal State Optimization

    NASA Technical Reports Server (NTRS)

    Lafleur, Jarret M.; Cerimele, Christopher J.

    2009-01-01

    From the perspective of atmospheric entry, descent, and landing (EDL), one of the most foreboding destinations in the solar system is Mars due in part to its exceedingly thin atmosphere. To benchmark best possible scenarios for evaluation of potential Mars EDL system designs, a study is conducted to optimize the entry-to-terminal-state portion of EDL for a variety of entry velocities and vehicle masses, focusing on the identification of potential benefits of enabling angle of attack modulation. The terminal state is envisioned as one appropriate for the initiation of terminal descent via parachute or other means. A particle swarm optimizer varies entry flight path angle, ten bank profile points, and ten angle of attack profile points to find maximum-final-altitude trajectories for a 10 30 m ellipsled at 180 different combinations of values for entry mass, entry velocity, terminal Mach number, and minimum allowable altitude. Parametric plots of maximum achievable altitude are shown, as are examples of optimized trajectories. It is shown that appreciable terminal state altitude gains (2.5-4.0 km) over pure bank angle control may be possible if angle of attack modulation is enabled for Mars entry vehicles. Gains of this magnitude could prove to be enabling for missions requiring high-altitude landing sites. Conclusions are also drawn regarding trends in the bank and angle of attack profiles that produce the optimal trajectories in this study, and directions for future work are identified.

  10. A hypersonic vehicle approach to planetary exploration

    NASA Technical Reports Server (NTRS)

    Murbach, Marcus S.

    1993-01-01

    An enhanced Mars network class mission using a lifting hypersonic entry vehicle is proposed. The basic vehicle, derived from a mature hypersonic flight system called SWERVE, offers several advantages over more conventional low L/D or ballistic entry systems. The proposed vehicle has greatly improved lateral and cross range capability (e.g., it is capable of reaching the polar regions during less than optimal mission opportunities), is not limited to surface target areas of low elevation, and is less susceptible to problems caused by Martian dust storms. Further, the integrated vehicle has attractive deployment features and allows for a much improved evolutionary path to larger vehicles with greater science capability. Analysis of the vehicle is aided by the development of a Mars Hypersonic Flight Simulator from which flight trajectories are obtained. Atmospheric entry performance of the baseline vehicle is improved by a deceleration skirt and transpiration cooling system which significantly reduce TPS (Thermal Protection System) and flight battery mass. The use of the vehicle is also attractive in that the maturity of the flight systems make it cost-competitive with the development of a conventional low L/D entry system. Finally, the potential application of similar vehicles to other planetary missions is discussed.

  11. Orion Entry, Descent, and Landing Simulation

    NASA Technical Reports Server (NTRS)

    Hoelscher, Brian R.

    2007-01-01

    The Orion Entry, Descent, and Landing simulation was created over the past two years to serve as the primary Crew Exploration Vehicle guidance, navigation, and control (GN&C) design and analysis tool at the National Aeronautics and Space Administration (NASA). The Advanced NASA Technology Architecture for Exploration Studies (ANTARES) simulation is a six degree-of-freedom tool with a unique design architecture which has a high level of flexibility. This paper describes the decision history and motivations that guided the creation of this simulation tool. The capabilities of the models within ANTARES are presented in detail. Special attention is given to features of the highly flexible GN&C architecture and the details of the implemented GN&C algorithms. ANTARES provides a foundation simulation for the Orion Project that has already been successfully used for requirements analysis, system definition analysis, and preliminary GN&C design analysis. ANTARES will find useful application in engineering analysis, mission operations, crew training, avionics-in-the-loop testing, etc. This paper focuses on the entry simulation aspect of ANTARES, which is part of a bigger simulation package supporting the entire mission profile of the Orion vehicle. The unique aspects of entry GN&C design are covered, including how the simulation is being used for Monte Carlo dispersion analysis and for support of linear stability analysis. Sample simulation output from ANTARES is presented in an appendix.

  12. Shuttle entry aerothermodynamic flight research - The Orbiter Experiments (OEX) Program

    NASA Technical Reports Server (NTRS)

    Throckmorton, David A.

    1992-01-01

    Results of the OEX program are summarized with emphasis on the information on entry aerothermodynamic phenomena derived from Space Shuttle operations. The discussion focuses on OEX experiment complement and operational history, freestream environment and vehicle attitude data, aerodynamic force and moment data, aerodynamic surface data, and vehicle configuration data. Attention is also given to orbiter aerodynamic performance, stability and control, high-altitude atmospheric density variability, direct simulation Monte Carlo validation, orbital drag variation, and computational fluid dynamic technique validation.

  13. 48 CFR 52.208-5 - Condition of Leased Vehicles.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Standards (49 CFR 571) and State safety regulations applicable to the vehicle. The Government shall accept... Vehicles. 52.208-5 Section 52.208-5 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION....208-5 Condition of Leased Vehicles. As prescribed in 8.1104(b), insert the following clause...

  14. Time card entry system

    SciTech Connect

    Montierth, B.S.

    1996-05-01

    The Time Card Entry System was developed to interface with the DOE Headquarters Electronic Time and Attendance (ETA) system. It features pop-up window pick lists for Work Breakdown Structure Numbers and Hour Codes and has extensive processing that ensures that time and attendance reported by the employee fulfills US Government/OMB requirements before Timekeepers process the data at the end of the two week payroll cycle using ETA. Tours of Duty (e.g. ten hour day, four day week with Friday through Sunday off), established in the ETA system, are imported into the Time Card Entry System by the Timekeepers. An individual`s Tour of Duty establishes the basis for validation of time of day and number of hours worked per day. At the end of the two week cycle, data is exported by the Timekeepers from the Time Card Entry System into ETA data files.

  15. Shuttle entry guidance

    NASA Technical Reports Server (NTRS)

    Harpold, J. C.; Graves, C. A., Jr.

    1978-01-01

    This paper describes the design of the entry guidance for the Space Shuttle Orbiter. This guidance provides the steering commands for trajectory control from initial penetration of the earth's atmosphere until the terminal area guidance is activated at an earth-relative speed of 2500 fps. At this point, the Orbiter is at a distance of about 50 nmi from the runway threshold, and at an altitude of about 80,000 ft. The entry guidance design is based on an analytic solution of the equations of motion defining the drag acceleration profile that meets the terminal criteria of the entry flight while maintaining the flight within systems and operational constraints. Guidance commands, which are based on a control law that ensures damping of oscillatory type trajectory motion, are computed to steer the Orbiter to this drag acceleration profile.

  16. Communications Blackout Predictions for Atmospheric Entry of Mars Science Laboratory

    NASA Technical Reports Server (NTRS)

    Morabito, David D.; Edquist, Karl T.

    2005-01-01

    The Mars Science Laboratory (MSL) is expected to be a long-range, long-duration science laboratory rover on the Martian surface. MSL will provide a significant milestone that paves the way for future landed missions to Mars. NASA is studying options to launch MSL as early as 2009. There are three elements to the spacecraft; carrier (cruise stage), entry vehicle, and rover. The rover will have a UHF proximity link as the primary path for EDL communications and may have an X-band direct-to-Earth link as a back-up. Given the importance of collecting critical event telemetry data during atmospheric entry, it is important to understand the ability of a signal link to be maintained, especially during the period near peak convective heating. The received telemetry during entry (or played back later) will allow for the performance of the Entry-Descent-Landing technologies to be assessed. These technologies include guided entry for precision landing, a new sky-crane landing system and powered descent. MSL will undergo an entry profile that may result in a potential communications blackout caused by ionized particles for short periods near peak heating. The vehicle will use UHF and possibly X-band during the entry phase. The purpose of this rep0rt is to quantify or bound the likelihood of any such blackout at UHF frequencies (401 MHz) and X-band frequencies (8.4 GHz). Two entry trajectory scenarios were evaluated: a stressful entry trajectory to quantify an upper-bound for any possible blackout period, and a nominal trajectory to quantify likelihood of blackout for such cases.

  17. Communications Blackout Predictions for Atmospheric Entry of Mars Science Laboratory

    NASA Technical Reports Server (NTRS)

    Morabito, David D.; Edquist, Karl

    2005-01-01

    The Mars Science Laboratory (MSL) is expected to be a long-range, long-duration science laboratory rover on the Martian surface. MSL will provide a significant milestone that paves the way for future landed missions to Mars. NASA is studying options to launch MSL as early as 2009. MSL will be the first mission to demonstrate the new technology of 'smart landers', which include precision landing and hazard avoidance in order to -land at scientifically interesting sites that would otherwise be unreachable. There are three elements to the spacecraft; carrier (cruise stage), entry vehicle, and rover. The rover will have an X-band direct-to-Earth (DTE) link as well as a UHF proximity link. There is also a possibility of an X-band proximity link. Given the importance of collecting critical event telemetry data during atmospheric entry, it is important to understand the ability of a signal link to be maintained, especially during the period near peak convective heating. The received telemetry during entry (or played back later) will allow for the performance of the Entry-Descent-Landing technologies to be assessed. These technologies include guided entry for precision landing, hazard avoidance, a new sky-crane landing system and powered descent. MSL will undergo an entry profile that may result in a potential communications blackout caused by ionized plasma for short periods near peak heating. The vehicle will use UHF and possibly X-band during the entry phase. The purpose of this report is to quantify or bound the likelihood of any such blackout at UHF frequencies (401 MHz) and X-band frequencies (8.4 GHz). Two entry trajectory scenarios were evaluated: a stressful entry trajectory to quantify an upper-bound for any possible blackout period, and a nominal likely trajectory to quantify likelihood of blackout for such cases.

  18. Entry Systems Panel deliberations

    NASA Technical Reports Server (NTRS)

    Rasky, Daniel J.; Rummler, Donald R.; Bersch, Charlie; Dixon, Sidney C.

    1993-01-01

    The Entry Systems Panel was chaired by Don Rummler, LaRC and Dan Rasky, ARC. As requested, each panel participant prior to the workshop prepared and delivered presentations to: (1) identify technology needs; (2) assess current programs; (3) identify technology gaps; and (4) identify highest payoff areas R&D. Participants presented background on the entry systems R&D efforts and operations experiences for the Space Shuttle Orbiter. These participants represented NASA Centers involved in research (Ames Research Center), development (Johnson Space Center) and operations (Kennedy Space Center) and the Shuttle Orbiter prime contractor. The presentations lead to the discovery of several lessons learned.

  19. 32 CFR 552.36 - Rights-of-entry for construction.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 3 2010-07-01 2010-07-01 true Rights-of-entry for construction. 552.36 Section 552.36 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY MILITARY RESERVATIONS AND NATIONAL CEMETERIES REGULATIONS AFFECTING MILITARY RESERVATIONS Acquisition of Real Estate and Interest Therein § 552.36 Rights-of-entry...

  20. Summary analysis of the Gemini entry aerodynamics

    NASA Technical Reports Server (NTRS)

    Whitnah, A. M.; Howes, D. B.

    1972-01-01

    The aerodynamic data that were derived in 1967 from the analysis of flight-generated data for the Gemini entry module are presented. These data represent the aerodynamic characteristics exhibited by the vehicle during the entry portion of Gemini 2, 3, 5, 8, 10, 11, and 12 missions. For the Gemini, 5, 8, 10, 11, and 12 missions, the flight-generated lift-to-drag ratios and corresponding angles of attack are compared with the wind tunnel data. These comparisons show that the flight generated lift-to-drag ratios are consistently lower than were anticipated from the tunnel data. Numerous data uncertainties are cited that provide an insight into the problems that are related to an analysis of flight data developed from instrumentation systems, the primary functions of which are other than the evaluation of flight aerodynamic performance.

  1. Orion Exploration Mission Entry Interface Target Line

    NASA Technical Reports Server (NTRS)

    Rea, Jeremy R.

    2016-01-01

    The Orion Multi-Purpose Crew Vehicle is required to return to the continental United States at any time during the month. In addition, it is required to provide a survivable entry from a wide range of trans-lunar abort trajectories. The Entry Interface (EI) state must be targeted to ensure that all requirements are met for all possible return scenarios, even in the event of no communication with the Mission Control Center to provide an updated EI target. The challenge then is to functionalize an EI state constraint manifold that can be used in the on-board targeting algorithm, as well as the ground-based trajectory optimization programs. This paper presents the techniques used to define the EI constraint manifold and to functionalize it as a set of polynomials in several dimensions.

  2. Combined Structural and Trajectory Control of Variable-Geometry Planetary Entry Systems

    NASA Technical Reports Server (NTRS)

    Quadrelli, Marco B.; Pellegrino, Sergio; Kwok, Kawai

    2011-01-01

    Some of the key challenges of planetary entry are to dissipate the large kinetic energy of the entry vehicle and to land with precision. Past missions to Mars were based on unguided entry, where entry vehicles carried payloads of less than 0.6 T and landed within 100 km of the designated target. The Mars Science Laboratory (MSL) is expected to carry a mass of almost 1 T to within 20 km of the target site. Guided lifting entry is needed to meet these higher deceleration and targeting demands. If the aerodynamic characteristics of the decelerator are variable during flight, more trajectory options are possible, and can be tailored to specific mission requirements. In addition to the entry trajectory modulation, having variable aerodynamic properties will also favor maneuvering of the vehicle prior to descent. For proper supersonic parachute deployment, the vehicle needs to turn to a lower angle of attack. One approach to entry trajectory improvement and angle of attack control is to embed a variable geometry decelerator in the design of the vehicle. Variation in geometry enables the vehicle to adjust its aerodynamic performance continuously without additional fuel cost because only electric power is needed for actuating the mechanisms that control the shape change. Novel structural and control concepts have been developed that enable the decelerator to undergo variation in geometry. Changing the aerodynamic characteristics of a flight vehicle by active means can potentially provide a mechanically simple, affordable, and enabling solution for entry, descent, and landing across a wide range of mission types, sample capture and return, and reentry to Earth, Titan, Venus, or Mars. Unguided ballistic entry is not sufficient to meet this more stringent deceleration, heating, and targeting demands. Two structural concepts for implementing the cone angle variation, a segmented shell, and a corrugated shell, have been presented.

  3. 40 CFR 86.1849-01 - Right of entry.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 20 2013-07-01 2013-07-01 false Right of entry. 86.1849-01 Section 86.1849-01 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution...

  4. 40 CFR 86.441-78 - Right of entry.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 19 2013-07-01 2013-07-01 false Right of entry. 86.441-78 Section 86.441-78 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission Regulations for 1978 and Later New Motorcycles, General Provisions...

  5. Orion Entry Performance-Based Center-of-Gravity Box

    NASA Technical Reports Server (NTRS)

    Rea, Jeremy R.

    2010-01-01

    The Orion capsule is designed both for Low Earth Orbit missions to the ISS and for missions to the moon. For ISS class missions, the capsule will use an Apollo-style direct entry. For lunar return missions, depending on the timing of the mission, the capsule could perform a direct entry or a skip entry of up to 4800 n.mi. in order to land in the coastal waters of California. The physics of atmospheric re-entry determine the capability of the Orion vehicle. For a given vehicle mass and shape, physics tells us that the driving parameters for an entry vehicle are the hypersonic lift-to-drag ratio (L/D) and the flight path angle at entry interface (gamma(sub EI)). The design of the Orion atmospheric re-entry must meet constraints during both nominal and dispersed flight conditions on landing accuracy, heating rate, total heat load, sensed acceleration, and proper disposal of the Service Module. These constraints define an entry corridor in the space of L/D-gamma(sub EI); if the vehicle falls within this corridor, then all constraints are met. The gamma(sub EI) dimension of the corridor can be further constrained by the gloads experienced during emergency entries. Thus, the entry performance for the Orion vehicle can be described completely by the L/D. Bounds on the hypersonic L/D necessary to achieve all the mission requirements can be defined for the given entry corridor. Landing accuracy performance drives the lower limit on L/D. In order to achieve the desired landing accuracy, a minimum L/D must be ensured. The design of the Thermal Protection System (TPS) drives the upper limit on L/D. A higher L/D can drive mass into the design of the TPS. Conversely, once the TPS is designed, the L/D must be ensured to stay below a certain limit in order for the TPS to stay within its design envelop. The L/D must stay within its upper and lower bounds during dispersed flight conditions. L/D is a function of both the aerodynamics and the center-of-gravity (CG) of the vehicle. The

  6. Flavivirus Entry Inhibitors.

    PubMed

    Wang, Qing-Yin; Shi, Pei-Yong

    2015-09-11

    Many flaviviruses are significant human pathogens that are transmitted by mosquitoes and ticks. Although effective vaccines are available for yellow fever virus, Japanese encephalitic virus, and tick-borne encephalitis virus, these and other flaviviruses still cause thousands of human deaths and millions of illnesses each year. No clinically approved antiviral therapy is available for flavivirus treatment. To meet this unmet medical need, industry and academia have taken multiple approaches to develop antiflavivirus therapy, among which targeting viral entry has been actively pursued in the past decade. Here we review the current knowledge of flavivirus entry and its use for small molecule drug discovery. Inhibitors of two major steps of flaviviral entry have been reported: (i) molecules that block virus-receptor interaction; (ii) compounds that prevent conformational change of viral envelope protein during virus-host membrane fusion. We also discuss the advantages and disadvantages of targeting viral entry for treatment of flavivirus infection as compared to targeting viral replication proteins. PMID:27617926

  7. Think Exit at Entry

    ERIC Educational Resources Information Center

    O'Rourke, Tom; Satterfield, Coy E.

    2005-01-01

    This paper describes the "Think Exit at Entry" program that has become the guiding principle for the Georgia Department of Juvenile Justice (DJJ). The Georgia DJJ believes that the transition process begins the day the youth enters the system and continues well after release from the institution. Literature points the need for transition planning…

  8. Double-Entry Bookkeeping.

    ERIC Educational Resources Information Center

    Snyder, Herbert

    1999-01-01

    Explains the principles and mechanics of double-entry bookkeeping as a part of the accounting cycle to produce a functioning set of accounting records. Suggests that libraries need to have accurate and timely information about their spending to gain financial control and protect against fraud and abuse. (LRW)

  9. 9. FIRST FLOOR, ENTRY HALL, LOOKING SOUTHWEST TOWARDS FRONT ENTRY ...

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

    9. FIRST FLOOR, ENTRY HALL, LOOKING SOUTHWEST TOWARDS FRONT ENTRY WITH OPEN DOORWAY TO WINDER STAIRWAY ON RIGHT - Open Gate Farm, House, Ridge Road, 1 mile East of Elephant Road, Perkasie, Bucks County, PA

  10. INTERIOR OF ENTRY HALLWAY AND STEEL ENTRY DOOR ON SOUTH ...

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

    INTERIOR OF ENTRY HALLWAY AND STEEL ENTRY DOOR ON SOUTH SIDE, VIEW FACING NORTHEAST. - Naval Air Station Barbers Point, Telephone Exchange, Coral Sea Road north of Bismarck Sea Road, Ewa, Honolulu County, HI

  11. Pioneer Venus multiprobe entry telemetry recovery

    NASA Technical Reports Server (NTRS)

    Miller, R. B.; Ramos, R.

    1980-01-01

    The entry phase of the Pioneer Venus Multiprobe Mission involved data transmission over a two hour span. The criticality of recovering those two hours of data, coupled with the fact that there were no radio signals from the probes until their arrival at Venus, dictated unique telemetry recovery approaches on the ground. The result was double redundancy, use of spectrum analyzers to aid in rapid acquisition of the signals, and development of a technique for recovery of telemetry data without the use of real time coherent detection, which is normally employed for all other planetary missions.

  12. Space Shuttle Orbiter entry through landing navigation

    NASA Technical Reports Server (NTRS)

    Ewell, J. J., Jr.

    1982-01-01

    The Space Shuttle Orbiter navigation system must be capable of determining its position and velocity throughout a variety of operational regimes. The design and operation of the entry through landing navigation system is described as it operates during a nominal end of mission from the orbital coasting phase throughout atmospheric flight and landing. Design and operation of the Kalman filter is described. Stabilization of the altitude channel prior to acquisition of external measurement data is described. Utilization of the Tactical Air Navigation (TACAN), barometric altimeter, and Microwave Scan Beam Landing System external measurement data is described. A comparison is made between predicted performance and the navigation accuracy observed during flight.

  13. 48 CFR 908.1170 - Leasing of fuel-efficient vehicles.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Leasing of fuel-efficient vehicles. 908.1170 Section 908.1170 Federal Acquisition Regulations System DEPARTMENT OF ENERGY COMPETITION ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Leasing of Motor Vehicles 908.1170 Leasing of fuel-efficient vehicles. (a)...

  14. Entry flight control system downmoding evaluation

    NASA Technical Reports Server (NTRS)

    Barnes, H. A.

    1978-01-01

    A method to desensitize the entry flight control system to structural vibration feedback which might induce an oscillatory instability is described. Trends in vehicle response and handling characteristics as a function of gain combinations in the FCS forward and rate feedback loops were described as observed in a man-in-the-loop simulation. Among the flight conditions considered are the effects of downmoding with APU failures, off-nominal trajectory conditions, sensed angle of attack errors, the impact on RCS fuel consumption, performance in the presence of aero variations, recovery from large FCS upsets, and default gains.

  15. The Effects of the Diurnal Atmospheric Variability on Entry, Descent and Landing on Mars

    NASA Astrophysics Data System (ADS)

    Marceta, D.

    2014-12-01

    Landing on Mars is extremely challenging task due to the fact that the Martian atmosphere is the most hostile environment in the Solar system to perform the entry, descent and landing (EDL) process, because it is thick enough to create substantial heating of the entry vehicle but not thick enough to reduce its velocity to the one necessary for safe landing. Beside this, the atmosphere is very dynamic mainly due to high eccentricity of the Martian orbit, obliquity of the orbital to the equatorial plane and close alignment of the winter solstice and the orbital perihelion. Although seasonal variations of atmospheric parameters are significantly larger than the diurnal, it is very important to analyze diurnal cycles as they can significantly change vertical and horizontal atmospheric profiles in very short time intervals. This can present a serious threat to missions which have very precise timings and specific requirements such as the requirement for the daytime landing to enable ground images acquisition during the descent and landing phase. A 3-degrees-of-freedom trajectory integration routine was combined with the Mars Global Reference Atmospheric Model (Mars-GRAM) to identify the dependence of the EDL profiles on the diurnal cycles of atmospheric parameters throughout the Martian year. The obtained results show that the influence of the diurnal cycles is the largest at the equator and decreases relatively symmetrically towards the poles with a slightly stronger influence in the northern hemisphere. Also, there is a significant influence of the orbital position of Mars on the effect of diurnal atmospheric variations which causes that, around the orbital perihelion and winter solstice, there is some kind of inversion of the dependance of optimal entry timing on latitude of the landing site comparing to the rest of the Martian year.

  16. Adapting Mars Entry, Descent and Landing System for Earth

    NASA Astrophysics Data System (ADS)

    Heilimo, J.; Harri, A.-M.; Aleksashkin, S.; Koryanov, V.; Guerrero, H.; Schmidt, W.; Haukka, H.; Finchenko, V.; Martynov, M.; Ostresko, B.; Ponomarenko, A.; Kazakovtsev, V.; Arruego, I.; Martin, S.; Siili, T.

    2013-09-01

    In 2001 - 2011 an inflatable Entry, Descent and Landing System (EDLS) for Martian atmosphere was developed by FMI and the MetNet team. This MetNet Mars Lander EDLS is used in both the initial deceleration during atmospheric entry and in the final deceleration before the semi-hard impact of the penetrator to Martian surface. The EDLS design is ingenious and its applicability to Earth's atmosphere is studied in the on-going project. In particular, the behavior of the system in the critical transonic aerodynamic (from hypersonic to subsonic) regime will be investigated. This project targets to analyze and test the transonic behavior of this compact and light weight payload entry system to Earth's atmosphere [1]. Scaling and adaptation for terrestrial atmospheric conditions, instead of a completely new design, is a favorable approach for providing a new re-entry vehicle for terrestrial space applications.

  17. Atmospheric Entry Studies for Uranus

    NASA Astrophysics Data System (ADS)

    Agrawal, P.; Allen, G. A.; Hwang, H. H.; Marley, M. S.; McGuire, M. K.; Garcia, J. A.; Sklyanskiy, E.; Huynh, L. C.; Moses, R. W.

    2014-06-01

    To better understand the technology requirements for a Uranus atmospheric entry probe, an internal NASA study funded by ISPT program was conducted. The talk describes two different approaches to the planet: 1) direct ballistic entry and 2) Aerocapture.

  18. Entry systems technology assessment

    NASA Technical Reports Server (NTRS)

    Gay, Archie

    1993-01-01

    The objectives are: (1) to establish aerothermal environments for hypersonic aerospace vehicles; (2) to develop thermostructural design concepts; (3) to obtain optimum thermostructural designs by performing trade studies; and (4) to identify areas for further development.

  19. Three-dimensional acceleration planning for atmospheric entry

    NASA Astrophysics Data System (ADS)

    Chen, David Teh-Han

    The next generation of reusable launch vehicles will benefit from an improved entry guidance algorithm. Improvements have been made to the current Space Shuttle entry guidance algorithm that will provide an ability to handle aborts, reach large crossranges, and provide complete onboard planning capability. Building on the entry guidance algorithm for the Space Shuttle, three versions of a three-dimensional acceleration based entry guidance algorithm have been created and tested. The Space Shuttle entry guidance algorithm is extended to three dimensions by planning the drag profile and the occurrence of bank reversals. The three versions of the planning algorithm that have been developed are a single bank reversal planner, a two bank reversal planner, and a single bank reversal update planner. Tests of the single and two bank reversal versions show that the planning algorithms are capable of producing feasible trajectories for a wide range of various entry conditions. Integration and testing of the update planning algorithm with a feedback linearizing control law in a high fidelity simulation developed by NASA Marshall has demonstrated the algorithm's ability to handle a variety of entry conditions in an onboard environment.

  20. Shuttle Entry Imaging Using Infrared Thermography

    NASA Technical Reports Server (NTRS)

    Horvath, Thomas; Berry, Scott; Alter, Stephen; Blanchard, Robert; Schwartz, Richard; Ross, Martin; Tack, Steve

    2007-01-01

    During the Columbia Accident Investigation, imaging teams supporting debris shedding analysis were hampered by poor entry image quality and the general lack of information on optical signatures associated with a nominal Shuttle entry. After the accident, recommendations were made to NASA management to develop and maintain a state-of-the-art imagery database for Shuttle engineering performance assessments and to improve entry imaging capability to support anomaly and contingency analysis during a mission. As a result, the Space Shuttle Program sponsored an observation campaign to qualitatively characterize a nominal Shuttle entry over the widest possible Mach number range. The initial objectives focused on an assessment of capability to identify/resolve debris liberated from the Shuttle during entry, characterization of potential anomalous events associated with RCS jet firings and unusual phenomenon associated with the plasma trail. The aeroheating technical community viewed the Space Shuttle Program sponsored activity as an opportunity to influence the observation objectives and incrementally demonstrate key elements of a quantitative spatially resolved temperature measurement capability over a series of flights. One long-term desire of the Shuttle engineering community is to calibrate boundary layer transition prediction methodologies that are presently part of the Shuttle damage assessment process using flight data provided by a controlled Shuttle flight experiment. Quantitative global imaging may offer a complementary method of data collection to more traditional methods such as surface thermocouples. This paper reviews the process used by the engineering community to influence data collection methods and analysis of global infrared images of the Shuttle obtained during hypersonic entry. Emphasis is placed upon airborne imaging assets sponsored by the Shuttle program during Return to Flight. Visual and IR entry imagery were obtained with available airborne

  1. RITD - Adapting Mars Entry, Descent and Landing System for Earth

    NASA Astrophysics Data System (ADS)

    Heilimo, Jyri; Aleksashkin, Sergey; Martynov, Maxim; Schmidt, Walter; Harri, Ari-Matti; Vsevolod Koryanov, D.; Kazakovtcev, Victor; Haukka, Harri; Arruego, Ignacio; Finchenko, Valery; Ostresko, Boris; Ponomarenko, Andrei; Martin, Susanna; Siili, Tero

    Abstract A new generation of inflatable Entry, Descent and Landing System (EDLS) or Mars has been developed. It is used in both the initial atmospheric entry and atmospheric descent before the semi-hard impact of the penetrator into Martian surface. The EDLS applicability to Earth’s atmosphere is studied by the EU/RITD [1] project. Project focuses to the analysis and tests of the transonic behaviour of this compact and light weight payload entry system at the Earth re-entry 1. EDLS for Earth The dynamical stability of the craft is analysed, concentrating on the most critical part of the atmospheric re-entry, the transonic phase. In Martian atmosphere the MetNet vehicle stability during the transonic phase is understood. However, in the more dense Earth’s atmosphere, the transonic phase is shorter and turbulence more violent. Therefore, the EDLS has to be sufficiently dynamically stable to overcome the forces tending to deflect the craft from its nominal trajectory and attitude. The preliminary design of the inflatable EDLS for Earth will be commenced once the scaling of the re-entry system and the dynamical stability analysis have been performed. The RITD-project concentrates on mission and applications achievable with the current MetNet-type (i.e. “Mini-1” category) of lander, and on requirements posed by other type Earth re-entry concepts. 2. Entry Angle Determination for Mini-1 - lander For successful Earth landing, the suitable re-entry angle and velocity with specific descent vehicle (DV) mass and heat flux parameters need to be determined. These key parameters in determining the Earth re-entry for DV are: - qmax (kW/m2): maximal specific heat flux, - Q (MJ/m2): specific integral heat flux to DV front shield, - m (kg): descent vehicle (DV) mass, - V (m/s): re-entry velocity and - theta(deg.): flight-path angle at Earth re-entry For Earth re-entry, the calculation results in the optimal value of entry velocity for MetNet (“Mini-1” category) -type

  2. RITD - Adapting Mars Entry, Descent and Landing System for Earth

    NASA Astrophysics Data System (ADS)

    Heilimo, Jyri; Harri, Ari-Matti; Aleksashkin, Sergey; Koryanov, Vsevolod; Arruego, Ignacio; Schmidt, Walter; Haukka, Harri; Finchenko, Valery; Martynov, Maxim; Ostresko, Boris; Ponomarenko, Andrey; Kazakovtsev, Viktor; Martin, Susanna; Siili, Tero

    2014-05-01

    A new generation of inflatable Entry, Descent and Landing System (EDLS) for Mars has been developed. It is used in both the initial atmospheric entry and atmospheric descent before the semi-hard impact of the penetrator into Martian surface. The EDLS applicability to Earth's atmosphere is studied by the EU/RITD [1] project. Project focuses to the analysis and tests of the transonic behaviour of this compact and light weight payload entry system at the Earth re-entry. 1. EDLS for Earth The dynamical stability of the craft is analysed, concentrating on the most critical part of the atmospheric re-entry, the transonic phase. In Martian atmosphere the MetNet vehicle stability during the transonic phase is understood. However, in the more dense Earth's atmosphere, the transonic phase is shorter and turbulence more violent. Therefore, the EDLS has to be sufficiently dynamically stable to overcome the forces tending to deflect the craft from its nominal trajectory and attitude. The preliminary design of the inflatable EDLS for Earth will be commenced once the scaling of the re-entry system and the dynamical stability analysis have been performed. The RITD-project concentrates on mission and applications achievable with the current MetNet-type (i.e. 'Mini-1' category) of lander, and on requirements posed by other type Earth re-entry concepts. 2. Entry Angle Determination for Mini-1 - lander For successful Earth landing, the suitable re-entry angle and velocity with specific descent vehicle (DV) mass and heat flux parameters need to be determined. These key parameters in determining the Earth re-entry for DV are: qmax (kW/m2): maximal specific heat flux, Q (MJ/m2): specific integral heat flux to DV front shield, m (kg): descent vehicle (DV) mass, V (m/s): re-entry velocity and Θ (deg.): flight-path angle at Earth re-entry For Earth re-entry, the calculation results in the optimal value of entry velocity for MetNet ('Mini-1' category) -type lander, with mass of 22kg, being

  3. Advanced entry guidance algorithm with landing footprint computation

    NASA Astrophysics Data System (ADS)

    Leavitt, James Aaron

    The design and performance evaluation of an entry guidance algorithm for future space transportation vehicles is presented. The algorithm performs two functions: on-board trajectory planning and trajectory tracking. The planned longitudinal path is followed by tracking drag acceleration, as is done by the Space Shuttle entry guidance. Unlike the Shuttle entry guidance, lateral path curvature is also planned and followed. A new trajectory planning function for the guidance algorithm is developed that is suitable for suborbital entry and that significantly enhances the overall performance of the algorithm for both orbital and suborbital entry. In comparison with the previous trajectory planner, the new planner produces trajectories that are easier to track, especially near the upper and lower drag boundaries and for suborbital entry. The new planner accomplishes this by matching the vehicle's initial flight path angle and bank angle, and by enforcing the full three-degree-of-freedom equations of motion with control derivative limits. Insights gained from trajectory optimization results contribute to the design of the new planner, giving it near-optimal downrange and crossrange capabilities. Planned trajectories and guidance simulation results are presented that demonstrate the improved performance. Based on the new planner, a method is developed for approximating the landing footprint for entry vehicles in near real-time, as would be needed for an on-board flight management system. The boundary of the footprint is constructed from the endpoints of extreme downrange and crossrange trajectories generated by the new trajectory planner. The footprint algorithm inherently possesses many of the qualities of the new planner, including quick execution, the ability to accurately approximate the vehicle's glide capabilities, and applicability to a wide range of entry conditions. Footprints can be generated for orbital and suborbital entry conditions using a pre

  4. Time Card Entry System

    1996-05-07

    The Time Card Entry System was developed for the Department of Enegy, Idaho Operations Office (DOE-ID) to interface with the DOE headquarters (DOE-HQ) Electronic Time and Attendance (ETA) system for payroll. It features pop-up window pick lists for Work Breakdown Structure numbers and Hour Codes and has extensive processing that ensures that time and attendance reported by the employee fulfills U.S. Government/OMB requirements before Timekeepers process the data at the end of the two weekmore » payroll cycle using ETA. A tour of duty profile (e.g., ten hour day, four day week with Sunday, friday and Saturday off), previously established in the ETA system, is imported into the Time Card Entry System by the timekeepers. An individual''s profile establishes the basis for validation of time of day and number of hours worked per day. At the end of the two cycle, data is exported by the timekeepers from the Time Card Entry System into ETA files.« less

  5. Time Card Entry System

    SciTech Connect

    Montierth, B. S.

    1996-05-07

    The Time Card Entry System was developed for the Department of Enegy, Idaho Operations Office (DOE-ID) to interface with the DOE headquarters (DOE-HQ) Electronic Time and Attendance (ETA) system for payroll. It features pop-up window pick lists for Work Breakdown Structure numbers and Hour Codes and has extensive processing that ensures that time and attendance reported by the employee fulfills U.S. Government/OMB requirements before Timekeepers process the data at the end of the two week payroll cycle using ETA. A tour of duty profile (e.g., ten hour day, four day week with Sunday, friday and Saturday off), previously established in the ETA system, is imported into the Time Card Entry System by the timekeepers. An individual''s profile establishes the basis for validation of time of day and number of hours worked per day. At the end of the two cycle, data is exported by the timekeepers from the Time Card Entry System into ETA files.

  6. Acquisition strategies

    SciTech Connect

    Zimmer, M.J.; Lynch, P.W. )

    1993-11-01

    Acquiring projects takes careful planning, research and consideration. Picking the right opportunities and avoiding the pitfalls will lead to a more valuable portfolio. This article describes the steps to take in evaluating an acquisition and what items need to be considered in an evaluation.

  7. 48 CFR 52.208-4 - Vehicle Lease Payments.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 2 2013-10-01 2013-10-01 false Vehicle Lease Payments. 52....208-4 Vehicle Lease Payments. As prescribed in 8.1104(a), insert the following clause in solicitations and contracts for leasing motor vehicles, unless the motor vehicles are leased in foreign...

  8. 48 CFR 52.208-6 - Marking of Leased Vehicles.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 2 2013-10-01 2013-10-01 false Marking of Leased Vehicles....208-6 Marking of Leased Vehicles. As prescribed in 8.1104(c), insert the following clause in solicitations and contracts for leasing motor vehicles, unless the motor vehicles are leased in...

  9. 48 CFR 52.208-7 - Tagging of Leased Vehicles.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 2 2013-10-01 2013-10-01 false Tagging of Leased Vehicles....208-7 Tagging of Leased Vehicles. As prescribed in 8.1104(d), insert a clause substantially as follows: Tagging of Leased Vehicles (MAY 1986) While it is the intent that vehicles leased under this contract...

  10. 48 CFR 952.208-7 - Tagging of leased vehicles.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Tagging of leased vehicles... leased vehicles. As prescribed in 908.1104, insert the following clause when leasing commercial vehicles for periods in excess of 60 days: Tagging of Leased Vehicles (APR 1984) (a) DOE intends to use...

  11. 48 CFR 552.211-88 - Vehicle export preparation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 4 2013-10-01 2013-10-01 false Vehicle export preparation... Vehicle export preparation. As prescribed in 511.204(b)(8), insert the following clause: Vehicle Export Preparation (JAN 2010) Vehicles shall be prepared for export on wheels, unboxed, unless otherwise specified...

  12. 48 CFR 952.208-7 - Tagging of leased vehicles.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Tagging of leased vehicles... leased vehicles. As prescribed in 908.1104, insert the following clause when leasing commercial vehicles for periods in excess of 60 days: Tagging of Leased Vehicles (APR 1984) (a) DOE intends to use...

  13. Orion Entry Flight Control Stability and Performance

    NASA Technical Reports Server (NTRS)

    Strahan, Alan L.; Loe, Greg R.; Seiler, Pete

    2007-01-01

    The Orion Spacecraft will be required to perform entry and landing functions for both Low Earth Orbit (LEO) and Lunar return missions, utilizing only the Command Module (CM) with its unique systems and GN&C design. This paper presents the current CM Flight Control System (FCS) design to support entry and landing, with a focus on analyses that have supported its development to date. The CM FCS will have to provide for spacecraft stability and control while following guidance or manual commands during exo-atmospheric flight, after Service Module separation, translational powered flight required of the CM, atmospheric flight supporting both direct entry and skip trajectories down to drogue chute deploy, and during roll attitude reorientation just prior to touchdown. Various studies and analyses have been performed or are on-going supporting an overall FCS design with reasonably sized Reaction Control System (RCS) jets, that minimizes fuel usage, that provides appropriate command following but with reasonable stability and control margin. Results from these efforts to date are included, with particular attention on design issues that have emerged, such as the struggle to accommodate sub-sonic pitch and yaw control without using excessively large jets that could have a detrimental impact on vehicle weight. Apollo, with a similar shape, struggled with this issue as well. Outstanding CM FCS related design and analysis issues, planned for future effort, are also briefly be discussed.

  14. Influence of interplanetary trajectory selection on Mars atmospheric entry velocity

    NASA Technical Reports Server (NTRS)

    Striepe, Scott A.; Braun, Robert D.; Powell, Richard W.; Fowler, Wallace T.

    1993-01-01

    Many current manned Mars mission studies are using low lift-to-drag ratio (L/D) vehicles to aerobrake at both Mars and Earth. The use of these low L/D vehicles could limit the allowable velocity at the atmospheric interface. This paper will demonstrate that if entry velocity constraints are incorporated into the interplanetary analysis of aerobraking Mars missions, many opportunities can be achieved for a small increase in initial mass in low-Earth orbit (IMLEO). These opportunities result from varying the initial launch date and the encounter dates and possibly using a powered Venus swingby on either the inbound or outbound transfer. This paper demonstrates this technique by using three atmospheric entry velocity ranges at Mars arrival (6.0-8.5, 6.4-8.1, and 7.2-7.3 km/s), unconstrained Mars entry velocities, and an Earth return entry velocity below 14 km/s. The results indicate that, by carefully selecting the interplanetary trajectory, an optimum IMLEO mission can be found for even highly restrictive entry velocity missions in practically all of the 15 yr studied.

  15. Mars Science Laboratory (MSL) Entry, Descent, and Landing Instrumentation (MEDLI): Complete Flight Data Set

    NASA Technical Reports Server (NTRS)

    Cheatwood, F. McNeil; Bose, Deepak; Karlgaard, Christopher D.; Kuhl, Christopher A.; Santos, Jose A.; Wright, Michael J.

    2014-01-01

    The Mars Science Laboratory (MSL) entry vehicle (EV) successfully entered the Mars atmosphere and landed the Curiosity rover safely on the surface of the planet in Gale crater on August 6, 2012. MSL carried the MSL Entry, Descent, and Landing (EDL) Instrumentation (MEDLI). MEDLI delivered the first in-depth understanding of the Mars entry environments and the response of the entry vehicle to those environments. MEDLI was comprised of three major subsystems: the Mars Entry Atmospheric Data System (MEADS), the MEDLI Integrated Sensor Plugs (MISP), and the Sensor Support Electronics (SSE). Ultimately, the entire MEDLI sensor suite consisting of both MEADS and MISP provided measurements that were used for trajectory reconstruction and engineering validation of aerodynamic, atmospheric, and thermal protection system (TPS) models in addition to Earth-based systems testing procedures. This report contains in-depth hardware descriptions, performance evaluation, and data information of the three MEDLI subsystems.

  16. Strypi VII R launch vehicle

    SciTech Connect

    Wente, H.A.

    1982-01-01

    The Strypi VII R is a three-stage solid propellant launch vehicle designed to boost payloads ranging from 50 to 300 pounds to re-entry environment conditions. The first stage, a fin-stabilized ballistic rocket boosts the final two stages into an exoatmospheric trajectory where an attitude control system (ACS) precesses the spinning stages into the re-entry attitude. The ACS section is then jettisoned, and ignition of the spin-stabilized upper stages is initiated at a time determined to provide a zero angle-of-attack at beginning of re-entry. Four vehicles have been flown carrying three different re-entry test vehicles. Originally designed for use with a Castor II motor, the highly aluminized propellant in the first stage spinning environment contributed to a case rupture resulting in failure of the second flight. The last two flights were flown successfully using Castor I motors. Typically, the Strypi VII R can boost a 100 lbm RV to a speed of 19,500 fps on a flight path of -30 degrees at 300,000 feet altitude.

  17. Entry guidance and entry autopilot (STS-1 baseline)

    NASA Technical Reports Server (NTRS)

    Harpold, J. C.; Hill, O.

    1980-01-01

    Preliminary entry guidance and autopilot software formulations, for use in the Mission Control Center (MCC) entry processor, are presented. The MCC requirements are met by a definition of coordinate systems, a list of parameter definitions for the software formulations, a description of the entry guidance detailed formulation requirements, a description of the detailed autopilot formualtion requirements, a description of the targeting routine, and a set of formulation flow charts.

  18. The ESA/NASA Multi-Aircraft ATV-1 Re-Entry Campaign: Analysis of Airborne Intensified Video Observations from the NASA/JSC Experiment

    NASA Technical Reports Server (NTRS)

    Barker, Ed; Maley, Paul; Mulrooney, Mark; Beaulieu, Kevin

    2009-01-01

    In September 2008, a joint ESA/NASA multi-instrument airborne observing campaign was conducted over the Southern Pacific ocean. The objective was the acquisition of data to support detailed atmospheric re-entry analysis for the first flight of the European Automated Transfer Vehicle (ATV)-1. Skilled observers were deployed aboard two aircraft which were flown at 12.8 km altitude within visible range of the ATV-1 re-entry zone. The observers operated a suite of instruments with low-light-level detection sensitivity including still cameras, high speed and 30 fps video cameras, and spectrographs. The collected data has provided valuable information regarding the dynamic time evolution of the ATV-1 re-entry fragmentation. Specifically, the data has satisfied the primary mission objective of recording the explosion of ATV-1's primary fuel tank and thereby validating predictions regarding the tanks demise and the altitude of its occurrence. Furthermore, the data contains the brightness and trajectories of several hundred ATV-1 fragments. It is the analysis of these properties, as recorded by the particular instrument set sponsored by NASA/Johnson Space Center, which we present here.

  19. Aerial robotic data acquisition system

    SciTech Connect

    Hofstetter, K.J.; Hayes, D.W.; Pendergast, M.M.; Corban, J.E.

    1993-12-31

    A small, unmanned aerial vehicle (UAV), equipped with sensors for physical and chemical measurements of remote environments, is described. A miniature helicopter airframe is used as a platform for sensor testing and development. The sensor output is integrated with the flight control system for real-time, interactive, data acquisition and analysis. Pre-programmed flight missions will be flown with several sensors to demonstrate the cost-effective surveillance capabilities of this new technology.

  20. 19 CFR 142.17 - One entry summary for multiple entries.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false One entry summary for multiple entries. 142.17...; DEPARTMENT OF THE TREASURY (CONTINUED) ENTRY PROCESS Entry Summary Documentation § 142.17 One entry summary... director may permit the filing of one entry summary for merchandise the subject of separate entries if:...

  1. NASA CEV Reference Entry GN&C System and Analysis

    NASA Technical Reports Server (NTRS)

    Munday, S.; Madsen, C.; Broome, J.; Gay, R.; Tigges, M.; Strahan, A.

    2007-01-01

    As part of its overall objectives, the Orion spacecraft will be required to perform entry and Earth landing functions for Low Earth Orbit (LEO) and Lunar missions. Both of these entry scenarios will begin with separation of the Service Module (SM), making them unique from other Orion mission phases in that only the Command Module (CM) portion of the Crew Exploration Vehicle (CEV) will be involved, requiring a CM specific Guidance, Navigation and Control (GN&C) system. Also common to these mission scenarios will be the need for GN&C to safely return crew (or cargo) to earth within the dynamic thermal and structural constraints of entry and within acceptable accelerations on the crew, utilizing the limited aerodynamic performance of the CM capsule. The lunar return mission could additionally require an initial atmospheric entry designed to support a precision skip and second entry, all to maximize downrange performance and ensure landing in the United States. This paper describes the Entry GN&C reference design, developed by the NASA-led team, that supports these entry scenarios and that was used to validate the Orion System requirements. Description of the reference design will include an overview of the GN&C functions, avionics, and effectors and will relate these to the specific design drivers of the entry scenarios, as well as the desire for commonality in vehicle systems to support the different missions. The discussion will also include the requirement for an Emergency Entry capability beyond that of the nominal performance of the multi-string GNC system, intended to return the crew to the earth in a survivable but unguided manner. Finally, various analyses will be discussed, including those completed to support validation efforts of the current CEV requirements, along with those on-going and planned with the intention to further refine the requirements and to support design development work in conjunction with the prime contractor. Some of these ongoing

  2. Mission Sizing and Trade Studies for Low Ballistic Coefficient Entry Systems to Venus

    NASA Technical Reports Server (NTRS)

    Dutta, Soumyo; Smith, Brandon; Prabhu, Dinesh; Venkatapathy, Ethiraj

    2012-01-01

    The U.S and the U.S.S.R. have sent seventeen successful atmospheric entry missions to Venus. Past missions to Venus have utilized rigid aeroshell systems for entry. This rigid aeroshell paradigm sets performance limitations since the size of the entry vehicle is constrained by the fairing diameter of the launch vehicle. This has limited ballistic coefficients (beta) to well above 100 kg/m2 for the entry vehicles. In order to maximize the science payload and minimize the Thermal Protection System (TPS) mass, these missions have entered at very steep entry flight path angles (gamma). Due to Venus thick atmosphere and the steep-gamma, high- conditions, these entry vehicles have been exposed to very high heat flux, very high pressures and extreme decelerations (upwards of 100 g's). Deployable aeroshells avoid the launch vehicle fairing diameter constraint by expanding to a larger diameter after the launch. Due to the potentially larger wetted area, deployable aeroshells achieve lower ballistic coefficients (well below 100 kg/m2), and if they are flown at shallower flight path angles, the entry vehicle can access trajectories with far lower decelerations (50-60 g's), peak heat fluxes (400 W/cm2) and peak pressures. The structural and TPS mass of the shallow-gamma, low-beta deployables are lower than their steep-gamma, high-beta rigid aeroshell counterparts at larger diameters, contributing to lower areal densities and potentially higher payload mass fractions. For example, at large diameters, deployables may attain aeroshell areal densities of 10 kg/m2 as opposed to 50 kg/m2 for rigid aeroshells. However, the low-beta, shallow-gamma paradigm also raises issues, such as the possibility of skip-out during entry. The shallow-gamma could also increase the landing footprint of the vehicle. Furthermore, the deployable entry systems may be flexible, so there could be fluid-structure interaction, especially in the high altitude, low-density regimes. The need for precision in

  3. 75 FR 41161 - Information Collection Requirement; Defense Federal Acquisition Regulation Supplement; Part 251...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-15

    ... Defense Acquisition Regulations System Information Collection Requirement; Defense Federal Acquisition... vehicles under the Interagency Fleet Management System (IFMS) and obtain related services. The information... Regulations System, Department of Defense (DoD). ACTION: Notice and request for comments regarding a...

  4. Development of FIAT-Based Parametric Thermal Protection System Mass Estimating Relationships for NASA's Multi-Mission Earth Entry Concept

    NASA Astrophysics Data System (ADS)

    Sepka, S. A.; Samareh, J. A.

    2014-06-01

    Mass estimating relationships have been formulated to determine a vehicle's Thermal Protection System material and required thickness for safe Earth entry. We focus on developing MERs, the resulting equations, model limitations, and model accuracy.

  5. Re-entry simulation chamber for thermo-mechanical characterisation of space materials

    NASA Astrophysics Data System (ADS)

    Liedtke, Volker

    2003-09-01

    During re-entry, materials and components are subject to very high thermal and mechanical loads. Any failure may cause loss of mission. Therefore, materials and components have to be tested under most rigid conditions to verify the suitability of the material and to verify the design of the components. The Re-Entry Simulation Chamber (RESiC) at ARC Seibersdorf research (ARCS) allows simulating the high thermal loads as well as complex mechanical load profiles that may occur during a re-entry; additionally, the influence of chemical reactions of materials with gaseous components of the atmosphere can be studied. The high vacuum chamber (better than 1×10-6 mbar) has a diameter of 650 mm and allows a sample height of 500 mm, or 1000 mm with extension flange. The gas dosing system is designed to emulate the increasing atmospheric pressure during the re-entry trajectory of a vehicle. Heating is performed by a 30 kW induction generator that allows a sufficiently rapid heating of larger components; electrically conductive materials such as metals or carbon fibre reinforced ceramics are directly heated, while for electrical insulators, susceptor plates or tubes will be employed. The uniaxial servo-hydraulic testing machine has a maximum load of 70 kN, either static or with a frequency of up to 70 Hz, with any given load profile (sinus, rectangular, triangular, ...). Strain measurements will be done by non-contacting laser speckle system for maximum flexibility and minimum instrumentation time effort (currently under application testing), or by strain gauges. All relevant process parameters are controlled and recorded by microcomputer. The highly sophisticated control software allows a convenient and reliable multi-channel data acquisition, e.g. temperatures at various positions of the test piece, pressure, loads, strains, and any other test data according to customer specifications; the data format is suitable for any further data processing. During the set-up and

  6. Computerized Physician Order Entry

    PubMed Central

    Khanna, Raman; Yen, Tony

    2014-01-01

    Computerized physician order entry (CPOE) has been promoted as an important component of patient safety, quality improvement, and modernization of medical practice. In practice, however, CPOE affects health care delivery in complex ways, with benefits as well as risks. Every implementation of CPOE is associated with both generally recognized and unique local factors that can facilitate or confound its rollout, and neurohospitalists will often be at the forefront of such rollouts. In this article, we review the literature on CPOE, beginning with definitions and proceeding to comparisons to the standard of care. We then proceed to discuss clinical decision support systems, negative aspects of CPOE, and cultural context of CPOE implementation. Before concluding, we follow the experiences of a Chief Medical Information Officer and neurohospitalist who rolled out a CPOE system at his own health care organization and managed the resulting workflow changes and setbacks. PMID:24381708

  7. Shuttle entry guidance revisited

    NASA Technical Reports Server (NTRS)

    Mease, Kenneth D.; Kremer, Jean-Paul

    1992-01-01

    The Shuttle entry guidance concept is reviewed which is aimed at tracking a reference drag trajectory that leads to the specified range and velocity for the initiation of the terminal energy management phase. An approximate method of constructing the domain of attraction is proposed, and its validity is ascertained by simulation. An alternative guidance law yielding global exponential tracking in the absence of control saturation is derived using a feedback linearization method. It is noted that the alternative guidance law does not improve on the stability and performance of the current guidance law, for the operating domain and control capability of the Shuttle. It is suggested that the new guidance law with a larger operating domain and increased lift-to-drag capability would be superior.

  8. 48 CFR 908.7101-5 - Used vehicles.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... purposes, or the vehicles are acquired from exchange sale. In accordance with 41 CFR 109-26.501-50 and 109... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Used vehicles. 908.7101-5... PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Acquisition of Special Items 908.7101-5 Used...

  9. 48 CFR 908.7101-5 - Used vehicles.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... purposes, or the vehicles are acquired from exchange sale. In accordance with DOE-PMR 41 CFR 109-38.5102... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Used vehicles. 908.7101-5... PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Acquisition of Special Items 908.7101-5 Used...

  10. Vehicle barrier with access delay

    DOEpatents

    Swahlan, David J; Wilke, Jason

    2013-09-03

    An access delay vehicle barrier for stopping unauthorized entry into secure areas by a vehicle ramming attack includes access delay features for preventing and/or delaying an adversary from defeating or compromising the barrier. A horizontally deployed barrier member can include an exterior steel casing, an interior steel reinforcing member and access delay members disposed within the casing and between the casing and the interior reinforcing member. Access delay members can include wooden structural lumber, concrete and/or polymeric members that in combination with the exterior casing and interior reinforcing member act cooperatively to impair an adversarial attach by thermal, mechanical and/or explosive tools.

  11. The Context of Superintendent Entry

    ERIC Educational Resources Information Center

    Lytle, James H.

    2009-01-01

    The current rhetoric about accountability, making adequate yearly progress, and focusing on quality classroom instruction obfuscates the core challenge in becoming a superintendent: How does one use the entry and transition process to learn what the real challenges and issues are in a school district? Can entry be used as a time for personal and…

  12. Aileron roll hysteresis effects on entry of space shuttle orbiter

    NASA Technical Reports Server (NTRS)

    Powell, R. W.

    1977-01-01

    Six-degree-of-freedom simulations of the space shuttle orbiter entry with control hysteresis were conducted on the NASA Langley Research Center interactive simulator known as the automatic reentry flight dynamics simulator. These simulations revealed that the vehicle can tolerate control hysteresis producing a + or - 50 percent change in the nominal aileron roll characteristics and an offset in the nominal characteristics equivalent to a + or - 5 deg aileron deflection with little increase in the reaction control system's fuel consumption.

  13. EXPERT: An atmospheric re-entry test-bed

    NASA Astrophysics Data System (ADS)

    Massobrio, F.; Viotto, R.; Serpico, M.; Sansone, A.; Caporicci, M.; Muylaert, J.-M.

    2007-06-01

    In recognition of the importance of an independent European access to the International Space Station (ISS) and in preparation for the future needs of exploration missions, ESA is conducting parallel activities to generate flight data using atmospheric re-entry test-beds and to identify vehicle design solutions for human and cargo transportation vehicles serving the ISS and beyond. The EXPERT (European eXPErimental Re-entry Test-bed) vehicle represents the major on-going development in the first class of activities. Its results may also benefit in due time scientific missions to planets with an atmosphere and future reusable launcher programmes. The objective of EXPERT is to provide a test-bed for the validation of aerothermodynamics models, codes and ground test facilities in a representative flight environment, to improve the understanding of issues related to analysis, testing and extrapolation to flight. The vehicle will be launched on a sub-orbital trajectory using a Volna missile. The EXPERT concept is based on a symmetrical re-entry capsule whose shape is composed of simple geometrical elements. The suborbital trajectory will reach 120 km altitude and a re-entry velocity of 5 6km/s. The dimensions of the capsule are 1.6 m high and 1.3 m diameter; the overall mass is in the range of 250 350kg, depending upon the mission parameters and the payload/instrumentation complement. A consistent number of scientific experiments are foreseen on-board, from innovative air data system to shock wave/boundary layer interaction, from sharp hot structures characterisation to natural and induced regime transition. Currently the project is approaching completion of the phase B, with Alenia Spazio leading the industrial team and CIRA coordinating the scientific payload development under ESA contract.

  14. PredGuid+A: Orion Entry Guidance Modified for Aerocapture

    NASA Technical Reports Server (NTRS)

    Lafleur, Jarret

    2013-01-01

    PredGuid+A software was developed to enable a unique numerical predictor-corrector aerocapture guidance capability that builds on heritage Orion entry guidance algorithms. The software can be used for both planetary entry and aerocapture applications. Furthermore, PredGuid+A implements a new Delta-V minimization guidance option that can take the place of traditional targeting guidance and can result in substantial propellant savings. PredGuid+A allows the user to set a mode flag and input a target orbit's apoapsis and periapsis. Using bank angle control, the guidance will then guide the vehicle to the appropriate post-aerocapture orbit using one of two algorithms: Apoapsis Targeting or Delta-V Minimization (as chosen by the user). Recently, the PredGuid guidance algorithm was adapted for use in skip-entry scenarios for NASA's Orion multi-purpose crew vehicle (MPCV). To leverage flight heritage, most of Orion's entry guidance routines are adapted from the Apollo program.

  15. Reconstruction of the Genesis Entry

    NASA Technical Reports Server (NTRS)

    Desai, Prasun N.; Qualls, Garry D.; Schoenenberger, Mark

    2005-01-01

    This paper provides an overview of the findings from a reconstruction analysis of the Genesis capsule entry. First, a comparison of the atmospheric properties (density and winds) encountered during the entry to the pre-entry profile is presented. The analysis that was performed on the video footage (obtained from the tracking stations at UTTR) during the descent is then described from which the Mach number at the onset of the capsule tumble was estimated following the failure of the drogue parachute deployment. Next, an assessment of the Genesis capsule aerodynamics that was extracted from the video footage is discussed, followed by a description of the capsule hypersonic attitude that must have occurred during the entry based on examination of the recovered capsule heatshield. Lastly, the entry trajectory reconstruction that was performed is presented.

  16. 10 CFR 490.3 - Excluded vehicles.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Excluded vehicles. 490.3 Section 490.3 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM General Provisions § 490.3... has a fleet or to calculate alternative fueled vehicle acquisition requirements, the...

  17. 10 CFR 490.3 - Excluded vehicles.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Excluded vehicles. 490.3 Section 490.3 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM General Provisions § 490.3... has a fleet or to calculate alternative fueled vehicle acquisition requirements, the...

  18. 10 CFR 490.3 - Excluded vehicles.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Excluded vehicles. 490.3 Section 490.3 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM General Provisions § 490.3... has a fleet or to calculate alternative fueled vehicle acquisition requirements, the...

  19. 10 CFR 490.3 - Excluded vehicles.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Excluded vehicles. 490.3 Section 490.3 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM General Provisions § 490.3... has a fleet or to calculate alternative fueled vehicle acquisition requirements, the...

  20. 10 CFR 490.3 - Excluded vehicles.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Excluded vehicles. 490.3 Section 490.3 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM General Provisions § 490.3... has a fleet or to calculate alternative fueled vehicle acquisition requirements, the...

  1. 19 CFR 141.61 - Completion of entry and entry summary documentation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Completion of entry and entry summary documentation. (a) Preparation—(1) Paper entry and entry summary... 15422(a) of the Food, Conservation, and Energy Act of 2008 (Pub. L. 110-234), for all goods entered...

  2. 19 CFR 142.13 - When entry summary must be filed at time of entry.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... duties attached, if the entry/entry summary information and a valid scheduled statement date have been... estimated duties attached if the entry/entry summary information and a valid scheduled statement date...

  3. Magnetohydrodynamic Power Generation in the Laboratory Simulated Martian Entry Plasma

    NASA Technical Reports Server (NTRS)

    Vuskovic, L.; Popovic, S.; Drake, J.; Moses, R. W.

    2005-01-01

    This paper addresses the magnetohydrodynamic (MHD) conversion of the energy released during the planetary entry phase of an interplanetary vehicle trajectory. The effect of MHD conversion is multi-fold. It reduces and redirects heat transferred to the vehicle, and regenerates the dissipated energy in reusable and transportable form. A vehicle on an interplanetary mission carries about 10,000 kWh of kinetic energy per ton of its mass. This energy is dissipated into heat during the planetary atmospheric entry phase. For instance, the kinetic energy of Mars Pathfinder was about 4220 kWh. Based on the loss in velocity, Mars Pathfinder lost about 92.5% of that energy during the plasma-sustaining entry phase that is approximately 3900 kWh. An ideal MHD generator, distributed over the probe surface of Mars Pathfinder could convert more than 2000 kWh of this energy loss into electrical energy, which correspond to more than 50% of the kinetic energy loss. That means that the heat transferred to the probe surface can be reduced by at least 50% if the converted energy is adequately stored, or re-radiated, or directly used. Therefore, MHD conversion could act not only as the power generating, but also as the cooling process. In this paper we describe results of preliminary experiments with light and microwave emitters powered by model magnetohydrodynamic generators and discuss method for direct use of converted energy.

  4. 48 CFR 908.1170 - Leasing of fuel-efficient vehicles.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Leasing of fuel-efficient vehicles. 908.1170 Section 908.1170 Federal Acquisition Regulations System DEPARTMENT OF ENERGY COMPETITION ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Leasing of Motor Vehicles 908.1170 Leasing...

  5. On-Board Entry Trajectory Planning Expanded to Sub-orbital Flight

    NASA Technical Reports Server (NTRS)

    Lu, Ping; Shen, Zuojun

    2003-01-01

    A methodology for on-board planning of sub-orbital entry trajectories is developed. The algorithm is able to generate in a time frame consistent with on-board environment a three-degree-of-freedom (3DOF) feasible entry trajectory, given the boundary conditions and vehicle modeling. This trajectory is then tracked by feedback guidance laws which issue guidance commands. The current trajectory planning algorithm complements the recently developed method for on-board 3DOF entry trajectory generation for orbital missions, and provides full-envelope autonomous adaptive entry guidance capability. The algorithm is validated and verified by extensive high fidelity simulations using a sub-orbital reusable launch vehicle model and difficult mission scenarios including failures and aborts.

  6. Development of Inflatable Entry Systems Technologies

    NASA Technical Reports Server (NTRS)

    Player, Charles J.; Cheatwood, F. McNeil; Corliss, James

    2005-01-01

    Achieving the objectives of NASA s Vision for Space Exploration will require the development of new technologies, which will in turn require higher fidelity modeling and analysis techniques, and innovative testing capabilities. Development of entry systems technologies can be especially difficult due to the lack of facilities and resources available to test these new technologies in mission relevant environments. This paper discusses the technology development process to bring inflatable aeroshell technology from Technology Readiness Level 2 (TRL-2) to TRL-7. This paper focuses mainly on two projects: Inflatable Reentry Vehicle Experiment (IRVE), and Inflatable Aeroshell and Thermal Protection System Development (IATD). The objectives of IRVE are to conduct an inflatable aeroshell flight test that demonstrates exoatmospheric deployment and inflation, reentry survivability and stability, and predictable drag performance. IATD will continue the development of the technology by conducting exploration specific trade studies and feeding forward those results into three more flight tests. Through an examination of these projects, and other potential projects, this paper discusses some of the risks, issues, and unexpected benefits associated with the development of inflatable entry systems technology.

  7. DLMS voice data entry

    NASA Astrophysics Data System (ADS)

    Scott, P. B.

    1980-06-01

    This report describes the design, principles of operation, and performance characteristics of an Advanced Development Model of a voice recognition system (VRS) which can serve to input cartographic data to a computer. The completed system has been installed at the Defense Mapping Agency Aerospace Center (DMAAC) at St. Louis, MO, for evaluation and testing. The VRS is intended for use in entering by voice cartographic data to the Digital Landmass System (DLMS) Data Base. It was designed to satisfy the DMAAC product specifications. The software developed for the VRS includes two complete stand-alone programs. Performance tests conducted at TTI disclosed an average system word recognition accuracy of just under 99 percent for five talkers. The recognition tests were conducted by the use of tape recordings. These tape recordings were made during a previous contract involving cartographic data entry. Each person spoke approximately 536 words after uttering five training repetitions. The test results were virtually identical to those obtained during the previous contract.

  8. Trading Robustness Requirements in Mars Entry Trajectory Design

    NASA Technical Reports Server (NTRS)

    Lafleur, Jarret M.

    2009-01-01

    One of the most important metrics characterizing an atmospheric entry trajectory in preliminary design is the size of its predicted landing ellipse. Often, requirements for this ellipse are set early in design and significantly influence both the expected scientific return from a particular mission and the cost of development. Requirements typically specify a certain probability level (6-level) for the prescribed ellipse, and frequently this latter requirement is taken at 36. However, searches for the justification of 36 as a robustness requirement suggest it is an empirical rule of thumb borrowed from non-aerospace fields. This paper presents an investigation into the sensitivity of trajectory performance to varying robustness (6-level) requirements. The treatment of robustness as a distinct objective is discussed, and an analysis framework is presented involving the manipulation of design variables to effect trades between performance and robustness objectives. The scenario for which this method is illustrated is the ballistic entry of an MSL-class Mars entry vehicle. Here, the design variable is entry flight path angle, and objectives are parachute deploy altitude performance and error ellipse robustness. Resulting plots show the sensitivities between these objectives and trends in the entry flight path angles required to design to these objectives. Relevance to the trajectory designer is discussed, as are potential steps for further development and use of this type of analysis.

  9. Orbiter Boundary Layer Transition Stability Modeling at Flight Entry Conditions

    NASA Technical Reports Server (NTRS)

    Bartkowicz, Matt; Johnson, Heath; Candler, Graham; Campbell, Charles H.

    2009-01-01

    State of the art boundary layer stability modeling capabilities are increasingly seeing application to entry flight vehicles. With the advent of user friendly and robust implementations of two-dimensional chemical nonequilibrium stability modeling with the STABL/PSE-CHEM software, the need for flight data to calibrate such analyses capabilities becomes more critical. Recent efforts to perform entry flight testing with the Orbiter geometry related to entry aerothermodynamics and boundary layer transition is allowing for a heightened focus on the Orbiter configuration. A significant advancement in the state of the art can likely be achieved by establishing a basis of understanding for the occurrence of boundary layer transition on the Orbiter due to discrete protruding gap fillers and the nominal distributed roughness of the actual thermal protection system. Recent success in demonstrating centerline two-dimensional stability modeling on the centerline of the Orbiter at flight entry conditions provides a starting point for additional investigations. The more detailed paper will include smooth Orbiter configuration boundary layer stability results for several typical orbiter entry conditions. In addition, the numerical modeling approach for establishing the mean laminar flow will be reviewed and the method for determining boundary layer disturbance growth will be overviewed. In addition, if actual Orbiter TPS surface data obtained via digital surface scans become available, it may be possible to investigate the effects of an as-flown flight configuration on boundary layer transition compared to a smooth CAD reference.

  10. GOCE Re-Entry Campaign

    NASA Astrophysics Data System (ADS)

    Bastida, B.; Flohrer, T.; Lemmens, S.; Krag, H.

    2015-03-01

    Every year ESA, through the Space Debris Office, participates to an Inter-Agency Space Debris Coordination Committee (IADC) Re-entry Test Campaign.. For the campaign of 2013, ESA’s proposal to select GOCE's re-entry was accepted. The campaign opened on the 21st October 2013 after fuel depletion of the drag-compensating ion propulsion. GOCE was expected to enter into a phase of attitude-controlled fine-pointing mode (FPM) until the attitude controllers would be unable to cope with the atmospheric torques and then the satellite would enter in a phase of fully uncontrolled flight. In this paper, we present the evolution of ESA’s daily predictions on the re-entry epoch using different sources of orbital information. The uncertainties on the spacecraft operability (i.e. the physical limits of the attitude controller) led to a non-standard re-entry scenario were different attitudes had to be considered (instead of the commonly assumed random tumbling mode case that is used whenever no information on the physical properties of a re-entering object is available). A daily assessment of the status, in coordination with the flight control team, was required and implied a continuous update on the predicted failure point of the attitude controller. This in turn imposed the need for considering an asymmetric re-entry window. These operation-bound uncertainties were simulated to predict the attitude evolution after failure at different altitudes and their effects evaluated to be taken into account for the re-entry predictions. We present ESA’s re-entry prediction activities for GOCE, internally, and within the IADC, and address specific technical aspects and challenges for re-entry predictions, which are related to the expected and occurred attitude of GOCE during the final re-entry phase.

  11. 48 CFR 52.208-6 - Marking of Leased Vehicles.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Marking of Leased Vehicles. 52.208-6 Section 52.208-6 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION (CONTINUED) CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Text of Provisions and Clauses...

  12. Multi-Mission System Analysis for Planetary Entry (M-SAPE) Version 1

    NASA Technical Reports Server (NTRS)

    Samareh, Jamshid; Glaab, Louis; Winski, Richard G.; Maddock, Robert W.; Emmett, Anjie L.; Munk, Michelle M.; Agrawal, Parul; Sepka, Steve; Aliaga, Jose; Zarchi, Kerry; Mangini, Nancy; Perino, Scott; Bayandor, Javid; Liles, Charles

    2014-01-01

    This report describes an integrated system for Multi-mission System Analysis for Planetary Entry (M-SAPE). The system in its current form is capable of performing system analysis and design for an Earth entry vehicle suitable for sample return missions. The system includes geometry, mass sizing, impact analysis, structural analysis, flight mechanics, TPS, and a web portal for user access. The report includes details of M-SAPE modules and provides sample results. Current M-SAPE vehicle design concept is based on Mars sample return (MSR) Earth entry vehicle design, which is driven by minimizing risk associated with sample containment (no parachute and passive aerodynamic stability). By M-SAPE exploiting a common design concept, any sample return mission, particularly MSR, will benefit from significant risk and development cost reductions. The design provides a platform by which technologies and design elements can be evaluated rapidly prior to any costly investment commitment.

  13. Guidance and Control Architecture Design and Demonstration for Low Ballistic Coefficient Atmospheric Entry

    NASA Technical Reports Server (NTRS)

    Swei, Sean

    2014-01-01

    We propose to develop a robust guidance and control system for the ADEPT (Adaptable Deployable Entry and Placement Technology) entry vehicle. A control-centric model of ADEPT will be developed to quantify the performance of candidate guidance and control architectures for both aerocapture and precision landing missions. The evaluation will be based on recent breakthroughs in constrained controllability/reachability analysis of control systems and constrained-based energy-minimum trajectory optimization for guidance development operating in complex environments.

  14. Adaptable, Deployable Entry and Placement Technology (ADEPT) Overview of FY15 Accomplishments

    NASA Technical Reports Server (NTRS)

    Wercinski, P.; Brivkalns, C.; Cassell, A.; Chen, Y.-K.; Boghozian, T.; Chinnapongse, R.; Gasch, M.; Kruger, C.; Makino, A.; Milos, F.; Nishioka, O.; Smith, B.; Squire, T.; Venkatapathy, E.; Yount, B.; Zarchi, K.

    2015-01-01

    ADEPT is an atmospheric entry architecture for missions to most planetary bodies with atmospheres: Current Technology development project funded under STMD Game Changing Development Program (FY12 start); stowed inside the launch vehicle shroud and deployed in space prior to entry; low ballistic coefficient (less than 50 kilograms per square meter) provides a benign deceleration and thermal environment to the payload; High-temperature ribs support three dimensional woven carbon fabric to generate drag and withstand high heating.

  15. ESA Venus Entry Probe Study

    NASA Technical Reports Server (NTRS)

    vandenBerg, M. L.; Falkner, P.; Phipps, A.; Underwood, J. C.; Lingard, J. S.; Moorhouse, J.; Kraft, S.; Peacock, A.

    2005-01-01

    The Venus Entry Probe is one of ESA s Technology Reference Studies (TRS). The purpose of the Technology Reference Studies is to provide a focus for the development of strategically important technologies that are of likely relevance for future scientific missions. The aim of the Venus Entry Probe TRS is to study approaches for low cost in-situ exploration of Venus and other planetary bodies with a significant atmosphere. In this paper, the mission objectives and an outline of the mission concept of the Venus Entry Probe TRS are presented.

  16. Selected optimal shuttle entry computations

    NASA Technical Reports Server (NTRS)

    Sullivan, H. C.

    1974-01-01

    Parameterization and the Davidon-Fletcher-Powell method are used to study the characteristics of optimal shuttle entry trajectories. Two problems of thermal protective system weight minimization are considered: roll modulation and roll plus an angle-of-attack modulation. Both problems are targeted for the edges of the entry footprint. Results consistent with constraints on loads and control bounds are particularly well-behaved and strongly support 'energy' approximation results obtained for the case of symmetric flight by Kelley and Sullivan (1973). Furthermore, results indicate that optimal shuttle entry trajectories should be easy to duplicate and to analyze by using simple techniques.

  17. 27. View of entry door to vestibule to MWOC entry ...

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

    27. View of entry door to vestibule to MWOC entry door in transmitter building no. 102 (note coded key pad to left and intercom phone on left) and door to the central systems monitor room (CSMR) to right (out of sight). - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

  18. Adaptable Deployable Entry and Placement Technology (ADEPT)

    NASA Video Gallery

    The Adaptable, Deployable Entry Placement Technology (ADEPT) Project will test and demonstrate a deployable aeroshell concept as a viable thermal protection system for entry, descent, and landing o...

  19. Automated microbial metabolism laboratory. [Viking 75 entry vehicle and Mars

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The labeled release concept was advanced to accommodate a post- Viking mission designed to extend the search, to confirm the presence of, and to characterize any Martian life found, and to obtain preliminary information on control of the life detected. The advanced labeled release concept utilizes four test chambers, each of which contains either an active or heat sterilized sample of the Martian soil. A variety of C-14 labeled organic substrates can be added sequentially to each soil sample and the resulting evolved radioactive gas monitored. The concept can also test effects of various inhibitors and environmental parameters on the experimental response. The current Viking '75 labeled release hardware is readily adaptable to the advanced labeled release concept.

  20. Integrated Thermal Response Modeling System For Hypersonic Entry Vehicles

    NASA Technical Reports Server (NTRS)

    Chen, Y.-K.; Milos, F. S.; Partridge, Harry (Technical Monitor)

    2000-01-01

    We describe all extension of the Markov decision process model in which a continuous time dimension is included ill the state space. This allows for the representation and exact solution of a wide range of problems in which transitions or rewards vary over time. We examine problems based on route planning with public transportation and telescope observation scheduling.

  1. Approximation for maximum centerline heating on lifting entry vehicles.

    NASA Technical Reports Server (NTRS)

    Helms, V. T., III

    1973-01-01

    A centerline heating approximation is proposed in which only three basic equations need be solved. The heat rates correlate well with those obtained by more complex procedures. The approximation is readily adaptable to existing trajectory optimization programs to provide realistic surface temperature constraint capability with little increase in computer storage capacity and computer time. It is based on an analysis of heat-rate data computed for altitudes from 36,000 to 122,000 m, velocities from 600 to 7900 m/sec, and angles of attack from 0 to 60 degrees.

  2. 48 CFR 945.570-7 - Disposition of motor vehicles.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Disposition of motor... Disposition of motor vehicles. (a) The contractor shall dispose of DOE-owned motor vehicles as directed by the contracting officer. (b) DOE-owned motor vehicles may be disposed of as exchange/sale items when directed...

  3. 48 CFR 52.208-4 - Vehicle Lease Payments.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Vehicle Lease Payments. 52....208-4 Vehicle Lease Payments. As prescribed in 8.1104(a), insert the following clause in solicitations...: Vehicle Lease Payments (APR 1984) (a) Upon the submission of proper invoices or vouchers, the...

  4. 10 CFR 490.306 - Vehicle operation requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Fuel Provider Vehicle Acquisition Mandate § 490.306 Vehicle operation requirements. The alternative fueled..., except when these vehicles are operating in an area where the appropriate alternative fuel is unavailable....

  5. 10 CFR 490.306 - Vehicle operation requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Fuel Provider Vehicle Acquisition Mandate § 490.306 Vehicle operation requirements. The alternative fueled..., except when these vehicles are operating in an area where the appropriate alternative fuel is unavailable....

  6. 10 CFR 490.306 - Vehicle operation requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Fuel Provider Vehicle Acquisition Mandate § 490.306 Vehicle operation requirements. The alternative fueled..., except when these vehicles are operating in an area where the appropriate alternative fuel is unavailable....

  7. 10 CFR 490.306 - Vehicle operation requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Fuel Provider Vehicle Acquisition Mandate § 490.306 Vehicle operation requirements. The alternative fueled..., except when these vehicles are operating in an area where the appropriate alternative fuel is unavailable....

  8. 10 CFR 490.306 - Vehicle operation requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Fuel Provider Vehicle Acquisition Mandate § 490.306 Vehicle operation requirements. The alternative fueled..., except when these vehicles are operating in an area where the appropriate alternative fuel is unavailable....

  9. 48 CFR 52.208-4 - Vehicle Lease Payments.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 2 2014-10-01 2014-10-01 false Vehicle Lease Payments. 52....208-4 Vehicle Lease Payments. As prescribed in 8.1104(a), insert the following clause in solicitations...: Vehicle Lease Payments (APR 1984) (a) Upon the submission of proper invoices or vouchers, the...

  10. Electric vehicles

    SciTech Connect

    Not Available

    1990-03-01

    Quiet, clean, and efficient, electric vehicles (EVs) may someday become a practical mode of transportation for the general public. Electric vehicles can provide many advantages for the nation's environment and energy supply because they run on electricity, which can be produced from many sources of energy such as coal, natural gas, uranium, and hydropower. These vehicles offer fuel versatility to the transportation sector, which depends almost solely on oil for its energy needs. Electric vehicles are any mode of transportation operated by a motor that receives electricity from a battery or fuel cell. EVs come in all shapes and sizes and may be used for different tasks. Some EVs are small and simple, such as golf carts and electric wheel chairs. Others are larger and more complex, such as automobile and vans. Some EVs, such as fork lifts, are used in industries. In this fact sheet, we will discuss mostly automobiles and vans. There are also variations on electric vehicles, such as hybrid vehicles and solar-powered vehicles. Hybrid vehicles use electricity as their primary source of energy, however, they also use a backup source of energy, such as gasoline, methanol or ethanol. Solar-powered vehicles are electric vehicles that use photovoltaic cells (cells that convert solar energy to electricity) rather than utility-supplied electricity to recharge the batteries. This paper discusses these concepts.

  11. Cubesat Application for Planetary Entry (CAPE) Missions: Micro-Reentry Capsule (MIRCA)

    NASA Technical Reports Server (NTRS)

    Esper, Jaime

    2014-01-01

    The Cubesat Application for Planetary Entry Missions (CAPE) concept describes a high-performing Cubesat system which includes a propulsion module and miniaturized technologies capable of surviving atmospheric entry heating, while reliably transmitting scientific and engineering data. The Micro Return Capsule (MIRCA) is CAPEs first planetary entry probe flight prototype. Within this context, this paper briefly describes CAPEs configuration and typical operational scenario, and summarizes ongoing work on the design and basic aerodynamic characteristics of the prototype MIRCA vehicle. CAPE not only opens the door to new planetary mission capabilities, it also offers relatively low-cost opportunities especially suitable to university participation.

  12. 41 CFR 109-26.501-53 - Acquisitions by transfer.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false Acquisitions by transfer... Management Regulations System (Continued) DEPARTMENT OF ENERGY PROPERTY MANAGEMENT REGULATIONS SUPPLY AND... transfer. (a) The acquisition of passenger motor vehicles by transfer from another Government agency or...

  13. 41 CFR 109-26.501-53 - Acquisitions by transfer.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Acquisitions by transfer... Management Regulations System (Continued) DEPARTMENT OF ENERGY PROPERTY MANAGEMENT REGULATIONS SUPPLY AND... transfer. (a) The acquisition of passenger motor vehicles by transfer from another Government agency or...

  14. 41 CFR 109-26.501-53 - Acquisitions by transfer.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Acquisitions by transfer... Management Regulations System (Continued) DEPARTMENT OF ENERGY PROPERTY MANAGEMENT REGULATIONS SUPPLY AND... transfer. (a) The acquisition of passenger motor vehicles by transfer from another Government agency or...

  15. 41 CFR 109-26.501-53 - Acquisitions by transfer.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Acquisitions by transfer... Management Regulations System (Continued) DEPARTMENT OF ENERGY PROPERTY MANAGEMENT REGULATIONS SUPPLY AND... transfer. (a) The acquisition of passenger motor vehicles by transfer from another Government agency or...

  16. 41 CFR 109-26.501-53 - Acquisitions by transfer.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Acquisitions by transfer... Management Regulations System (Continued) DEPARTMENT OF ENERGY PROPERTY MANAGEMENT REGULATIONS SUPPLY AND... transfer. (a) The acquisition of passenger motor vehicles by transfer from another Government agency or...

  17. Drag-based composite super-twisting sliding mode control law design for Mars entry guidance

    NASA Astrophysics Data System (ADS)

    Zhao, Zhenhua; Yang, Jun; Li, Shihua; Guo, Lei

    2016-06-01

    In this paper, the drag-based trajectory tracking guidance problem is investigated for Mars entry vehicle subject to uncertainties. A composite super twisting sliding mode control method based on finite-time disturbance observer is proposed for guidance law design. The proposed controller not only eliminates the effects of matched and mismatched disturbances due to uncertainties of atmospheric models and vehicle aerodynamics but also guarantees the continuity of control action. Numerical simulations are carried out on the basis of Mars Science Laboratory mission, where the results show that the proposed methods can improve the Mars entry guidance precision as compared with some existing guidance methods including PID and ADRC.

  18. Syntax acquisition.

    PubMed

    Crain, Stephen; Thornton, Rosalind

    2012-03-01

    Every normal child acquires a language in just a few years. By 3- or 4-years-old, children have effectively become adults in their abilities to produce and understand endlessly many sentences in a variety of conversational contexts. There are two alternative accounts of the course of children's language development. These different perspectives can be traced back to the nature versus nurture debate about how knowledge is acquired in any cognitive domain. One perspective dates back to Plato's dialog 'The Meno'. In this dialog, the protagonist, Socrates, demonstrates to Meno, an aristocrat in Ancient Greece, that a young slave knows more about geometry than he could have learned from experience. By extension, Plato's Problem refers to any gap between experience and knowledge. How children fill in the gap in the case of language continues to be the subject of much controversy in cognitive science. Any model of language acquisition must address three factors, inter alia: 1. The knowledge children accrue; 2. The input children receive (often called the primary linguistic data); 3. The nonlinguistic capacities of children to form and test generalizations based on the input. According to the famous linguist Noam Chomsky, the main task of linguistics is to explain how children bridge the gap-Chomsky calls it a 'chasm'-between what they come to know about language, and what they could have learned from experience, even given optimistic assumptions about their cognitive abilities. Proponents of the alternative 'nurture' approach accuse nativists like Chomsky of overestimating the complexity of what children learn, underestimating the data children have to work with, and manifesting undue pessimism about children's abilities to extract information based on the input. The modern 'nurture' approach is often referred to as the usage-based account. We discuss the usage-based account first, and then the nativist account. After that, we report and discuss the findings of several

  19. Display integration for ground combat vehicles

    NASA Astrophysics Data System (ADS)

    Busse, David J.

    1998-09-01

    The United States Army's requirement to employ high resolution target acquisition sensors and information warfare to increase its dominance over enemy forces has led to the need to integrate advanced display devices into ground combat vehicle crew stations. The Army's force structure require the integration of advanced displays on both existing and emerging ground combat vehicle systems. The fielding of second generation target acquisition sensors, color digital terrain maps and high volume digital command and control information networks on these platforms define display performance requirements. The greatest challenge facing the system integrator is the development and integration of advanced displays that meet operational, vehicle and human computer interface performance requirements for the ground combat vehicle fleet. The subject of this paper is to address those challenges: operational and vehicle performance, non-soldier centric crew station configurations, display performance limitations related to human computer interfaces and vehicle physical environments, display technology limitations and the Department of Defense (DOD) acquisition reform initiatives. How the ground combat vehicle Program Manager and system integrator are addressing these challenges are discussed through the integration of displays on fielded, current and future close combat vehicle applications.

  20. Flowfield Analysis of a Small Entry Probe (SPRITE) Tested in an Arc Jet

    NASA Technical Reports Server (NTRS)

    Prabhu, Dinesh K.

    2012-01-01

    A novel concept of small size (diameter less than 15 inches) entry probes named SPRITE (Small Probe Re-entry Investigation for TPS Engineering) has been developed at NASA Ames Research Center (ARC). These flight probes have on-board data acquisition systems that have also been developed in parallel at NASA ARC by Greg Swanson1. Flight probes of this size facilitate testing over a wide range of conditions in arc jets available at NASA ARC, thereby fulfilling a 'test what you fly' paradigm. As indicated by the acronym, these probes, with suitably tailored trajectories, are primarily meant to be robotic flight test beds for TPS materials, although the design is flexible enough to accommodate additional objectives of flight-testing other vehicle subsystems. A first step towards establishing the feasibility of the SPRITE concept is to arc-jet test fully instrumented models at flight scale. In a follow-on to the Large-Scale Article Tests (LSAT2) performed in the 60 MW Interaction Heating Facility (IHF) in late 2008/early 2009, a full-scale model of Deep Space-2 (DS23) made of red oak was tested in the 20 MW Aerodynamic Heating Facility (AHF). There were no issues with mass capture by the diffuser for blunt bodies of roughly 15 inches diameter tested in the 18-inch nozzle of the AHF. Building on this initial success, two identical test articles - SPRITE-T1-1 and SPRITE-T1-2 (T1 indicating the choice of back shell geometry) - were fabricated, and one of them, SPRITE-T1-1, was tested in the AHF recently. Both these test articles, 14 inches in diameter, have a 45deg sphere-cone (like DS2) made of PICA bonded on to a 1/8th inch thick aluminum shell using RTV. The aft portion of the test article is a conical frustum (15deg cone angle) with LI-2200 bonded on to the aluminum shell. Each model is fully instrumented with: (a) thermocouples imbedded in plugs in the heat shield, (b) thermocouples bonded to the aluminum substructure; the thermocouples are distributed over the entire

  1. 32 CFR 763.4 - Entry restrictions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 5 2014-07-01 2014-07-01 false Entry restrictions. 763.4 Section 763.4 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY ISLANDS UNDER NAVY JURISDICTION RULES GOVERNING PUBLIC ACCESS Entry Regulations for Kaho'olawe Island, Hawaii § 763.4 Entry restrictions. (a) Entry by any person upon Kaho'olawe...

  2. 32 CFR 763.4 - Entry restrictions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 5 2012-07-01 2012-07-01 false Entry restrictions. 763.4 Section 763.4 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY ISLANDS UNDER NAVY JURISDICTION RULES GOVERNING PUBLIC ACCESS Entry Regulations for Kaho'olawe Island, Hawaii § 763.4 Entry restrictions. (a) Entry by any person upon Kaho'olawe...

  3. 32 CFR 763.4 - Entry restrictions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 5 2010-07-01 2010-07-01 false Entry restrictions. 763.4 Section 763.4 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY ISLANDS UNDER NAVY JURISDICTION RULES GOVERNING PUBLIC ACCESS Entry Regulations for Kaho'olawe Island, Hawaii § 763.4 Entry restrictions. (a) Entry by any person upon Kaho'olawe...

  4. 19 CFR 191.143 - Drawback entry.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... (CONTINUED) DRAWBACK Foreign-Built Jet Aircraft Engines Processed in the United States § 191.143 Drawback entry. (a) Filing of entry. Drawback entries covering these foreign-built jet aircraft engines shall be filed on Customs Form 7551, modified to show that the entry covers jet aircraft engines processed...

  5. 19 CFR 142.16 - Entry summary documentation.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 2 2011-04-01 2011-04-01 false Entry summary documentation. 142.16 Section 142.16... TREASURY (CONTINUED) ENTRY PROCESS Entry Summary Documentation § 142.16 Entry summary documentation. (a) Entry summary not filed at time of entry. When the entry documentation is filed before the entry...

  6. 19 CFR 142.16 - Entry summary documentation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Entry summary documentation. 142.16 Section 142.16... TREASURY (CONTINUED) ENTRY PROCESS Entry Summary Documentation § 142.16 Entry summary documentation. (a) Entry summary not filed at time of entry. When the entry documentation is filed before the entry...

  7. The Effects of the Variability of the Martian Atmosphere on Entry, Descent and Landing Scenarios

    NASA Astrophysics Data System (ADS)

    Marceta, Dusan; Segan, Stevo; Rasuo, Bosko

    Landing on Mars is extremely challenging task due to the fact that the Martian atmosphere is the most hostile environment in the Solar system to perform the entry, descent and landing (EDL) process because it is thick enough to create substantial heating of the entry vehicle but not thick enough to reduce its velocity to the values necessary for safe landing. Beside this, due to the high eccentricity of Martian orbit, which is almost six times larger than the Earth’s, there are large differences in energy received from the Sun throughout a Martian year. This difference, obliquity of the orbital to the equatorial plane and close alignment of the winter solstice and the orbital perihelion are the most important reasons of very dynamic behavior of the atmosphere of Mars. The variations of atmospheric parameters are not only extremely large but also very fast in space and time. Although seasonal variations of these parameters are for the order of magnitude larger than the diurnal, it is very important to analyze these diurnal variations because they can significantly change the vertical and horizontal atmospheric profiles in the very small time intervals. This can present serious threat to the missions which have very precise timings and specific requirement such as the requirement for the daytime landing to enable ground images acquisition. We have used Mars Global Reference Atmospheric Model (Mars-GRAM) which has been integrated into independently developed trajectory integration routine to identify the dependence of the EDL profiles on the diurnal cycles of the atmospheric parameters for different parts of the Martian year. The obtained result show that the influence of the diurnal cycle is the highest at equator and decreases relatively symmetrically toward the poles with a slightly stronger influence in the northern hemisphere. Also, there is a significant influence of the orbital position of Mars on the effect of the diurnal atmospheric variation which causes

  8. Computer assisted vehicle service featuring signature analysis and artificial intelligence

    SciTech Connect

    Boscove, J.A.; Kurtz, H.L.; Prince, J.E.; Wiegand, W.P.

    1989-01-03

    This patent describes a diagnostic method for use in diagnosing a vehicle utilizing a diagnostic system, the vehicle having an on-board computer control system for monitoring and controlling vehicle functions and the diagnostic system including a technician terminal having a diagnostic controller for processing diagnostic signals representative of vehicle conditions the controller having data entry means, data output means and storage means for storing vehicle parameters and diagnostic routines and the technician terminal having a display means for providing instructions for fault repair sequences.

  9. Descent vehicles

    NASA Technical Reports Server (NTRS)

    Popov, Y. I.

    1985-01-01

    The creation of descent vehicles marked a new stage in the development of cosmonautics, involving the beginning of manned space flight and substantial progress in space research on the distant bodies of the Solar System. This booklet describes these vehicles and their structures, systems, and purposes. It is intended for the general public interested in modern problems of space technology.

  10. Vehicle systems

    NASA Technical Reports Server (NTRS)

    Bales, Tom; Modlin, Tom; Suddreth, Jack; Wheeler, Tom; Tenney, Darrel R.; Bayless, Ernest O.; Lisagor, W. Barry; Bolstad, Donald A.; Croop, Harold; Dyer, J.

    1993-01-01

    Perspectives of the subpanel on expendable launch vehicle structures and cryotanks are: (1) new materials which provide the primary weight savings effect on vehicle mass/size; (2) today's investment; (3) typically 10-20 years to mature and fully characterize new materials.

  11. 75 FR 62482 - List of Nonconforming Vehicles Decided To Be Eligible for Importation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-12

    ... regulations published in the Federal Register on Tuesday, September 21, 2010, (75 FR 57396) that revised the... on this list for model year 1997-1998 Jeep Cherokee vehicles eligible for importation under vehicle eligibility number VSP-516 and the entry for model year 1997-2001 Jeep Cherokee vehicles eligible...

  12. Parametric entry corridors for lunar/Mars aerocapture missions

    NASA Technical Reports Server (NTRS)

    Ling, Lisa M.; Baseggio, Franco M.; Fuhry, Douglas P.

    1991-01-01

    Parametric atmospheric entry corridor data are presented for Earth and Mars aerocapture. Parameter ranges were dictated by the range of mission designs currently envisioned as possibilities for the Human Exploration Initiative (HEI). This data, while not providing a means for exhaustive evaluation of aerocapture performance, should prove to be a useful aid for preliminary mission design and evaluation. Entry corridors are expressed as ranges of allowable vacuum periapse altitude of the planetary approach hyperbolic orbit, with chart provided for conversion to an approximate flight path angle corridor at entry interface (125 km altitude). The corridor boundaries are defined by open-loop aerocapture trajectories which satisfy boundary constraints while utilizing the full aerodynamic control capability of the vehicle (i.e., full lift-up or full lift-down). Parameters examined were limited to those of greatest importance from an aerocapture performance standpoint, including the approach orbit hyperbolic excess velocity, the vehicle lift to drag ratio, maximum aerodynamic load factor limit, and the apoapse of the target orbit. The impact of the atmospheric density bias uncertainties are also included. The corridor data is presented in graphical format, and examples of the utilization of these graphs for mission design and evaluation are included.

  13. Lifting Entry & Atmospheric Flight (LEAF) Applications at Solar System Bodies.

    NASA Astrophysics Data System (ADS)

    Lee, G.; Sen, B.; Polidan, R. S.

    2015-12-01

    Introduction: Northrop Grumman and L'Garde have continued the development of a hypersonic entry, maneuverable platform capable of performing long-duration (months to a year) in situ and remote measurements at any solar system body that possesses an atmosphere. The Lifting Entry & Atmospheric Flight (LEAF) family of vehicles achieve this capability by using a semi-buoyant, ultra-low ballistic coefficient vehicle whose lifting entry allows it to enter the atmosphere without an aeroshell. In this presentation, we discuss the application of the LEAF system at various solar system bodies: Venus, Titan, Mars, and Earth. We present the key differences in platform design as well as operational differences required by the various target environments. The Venus implementation includes propulsive capability to reach higher altitudes during the day and achieves full buoyancy in the "habitable layers" of Venus' atmosphere at night. Titan also offers an attractive operating environment, allowing LEAF designs that can target low, medium, or high altitude operations, also with propulsive capabilities to roam within each altitude regime. The Mars version is a glider that descends gradually, allowing targeted delivery of payloads to the surface. Finally, an Earth version could remain in orbit in a stowed state until activated, allowing rapid response type deployments to any region of the globe.

  14. Feasibility of a driver performance data acquisition system

    SciTech Connect

    Carter, R.J.; Spelt, P.F.; Goodman, M.J.

    1994-06-01

    The National Highway Traffic Safety Administration (NHTSA) envisions many future situations in which the effectiveness and consequences of new intelligent vehicle-highway systems technologies will need to be studied in actual production vehicles. Such studies will enable evaluations in vehicles which are familiar to drivers. These studies would be future enhanced by the availability of an instrumentation package that can be easily installed in these vehicles to enable specific vehicle configurations of interest to be evaluated, thereby increasing the variety of vehicle options that are available for study. Ideally, an approach is needed that would allow data collection from a variety of vehicle models and types, and would address the issue of driver familiarity. Such an approach is embodied in the concept of a driver performance data acquisition system that could be installed in a wide range of vehicles within a relatively short period of time. As a universally adaptable system, it would provide researchers with the ability to manually input data as well as directly record information on driver, vehicle, roadway, and environmental parameters. Furthermore, it would enable the measurement of driver performance in the driver`s own vehicle, thereby ensuring vehicle familiarity. In addition, it would be possible to measure driver performance in relation to any vehicle design characteristic at relatively little expense and effort, and would make it easy to update existing models of driver/vehicle behavior to reflect performance characteristics in vehicles of current manufacture.

  15. Remote reconnaissance vehicle program. Final report

    SciTech Connect

    Giefer, D.; Hine, R.; Pavelek, M.

    1985-09-01

    This report documents the development and initial use of remote reconnaissance vehicle No. 1 (RRV-1) in the Three Mile Island Unit 2 (TMI-2) cleanup. The RRV-1 is a rugged, remotely operated, highly maneuverable six-wheeled vehicle which is tethered to transmit power and control signals. It has a system for controlled reel-in and pay-out of the tether, TV cameras with remotely controlled lighting, pan, tilt, and zoom capabilities and radiation detectors for floor, wall, and general area measurements. The design, development, and modifications of the vehicle and the operator training program are described, as are the TMI-2 reactor building modifications, the initial entries into the highly contaminated reactor building basement, the data gathered during the initial entries and recommendations for future improvements. The potential for future missions at TMI-2 and the general applicability of such remote devices to other nuclear power plants is also discussed.

  16. Draper Laboratory small autonomous aerial vehicle

    NASA Astrophysics Data System (ADS)

    DeBitetto, Paul A.; Johnson, Eric N.; Bosse, Michael C.; Trott, Christian A.

    1997-06-01

    The Charles Stark Draper Laboratory, Inc. and students from Massachusetts Institute of Technology and Boston University have cooperated to develop an autonomous aerial vehicle that won the 1996 International Aerial Robotics Competition. This paper describes the approach, system architecture and subsystem designs for the entry. This entry represents a combination of many technology areas: navigation, guidance, control, vision processing, human factors, packaging, power, real-time software, and others. The aerial vehicle, an autonomous helicopter, performs navigation and control functions using multiple sensors: differential GPS, inertial measurement unit, sonar altimeter, and a flux compass. The aerial transmits video imagery to the ground. A ground based vision processor converts the image data into target position and classification estimates. The system was designed, built, and flown in less than one year and has provided many lessons about autonomous vehicle systems, several of which are discussed. In an appendix, our current research in augmenting the navigation system with vision- based estimates is presented.

  17. Atmospheric entry heating of micrometeorites

    NASA Technical Reports Server (NTRS)

    Flynn, G. J.

    1989-01-01

    A computer simulation of the atmospheric entry deceleration and heating of cosmic dust particles has been developed and the predicted peak temperatures are compared to the earlier closed-form mathematical solutions of Whipple (195) and Fraundorf (1980). A 20-micron diameter particle of density 1 gm/cu cm having a velocity of 10 km/s at infinity and entering the atmosphere at normal incidence reaches a peak temperature of 1159 K. The duration of the heating pulse is about 8 s but the particle remains within 100 K of the peak temperature for only 1.0 s. As the angle of incidence decreases, the peak temperature reached on entry also decreases, and the duration of the temperature pulse increases. Comparison with the Whipple amd Fraundorf models indicates that they accurately assess the entry heating for cosmic dust particles of moderate or higher densities and entry angles near normal incidence. As particle density decreases or the entry angle nears grazing incidence, they overestimate the peak temperature.

  18. Mobile field data acquisition in geosciences

    NASA Astrophysics Data System (ADS)

    Golodoniuc, Pavel; Klump, Jens; Reid, Nathan; Gray, David

    2016-04-01

    module also features an interactive GIS component allowing to enter field observations as annotations to a map. The open communication protocols and file formats used by FAIMS modules allow easy integration with existing spatial data infrastructures and third-party applications, such as ArcGIS. The remoteness of the focus areas in the Capricorn region required reliable mechanisms for data replication and an added level of redundancy. This was achieved through the use of the FAIMS Server without adding a tightly coupled dependency on it - the mobile devices could continue to work independently in the case the server fails. To support collaborative fieldwork, "FAIMS on a Truck" offers networked collaboration within a field team using mobile applications as asynchronous rich clients. The framework runs on compatible Android devices (e.g., tablets, smart phones) with the network infrastructure supported by a FAIMS Server. The server component is installed in a field vehicle to provide data synchronisation between multiple mobile devices, backup and data transfer. The data entry process was streamlined and followed the workflow that field crews were accustomed to with added data validation capabilities. The use of a common platform allowed us to adopt the framework within multiple disciplines, improve data acquisition times, and reduce human-introduced errors. We continue to work with other research groups and continue to explore the possibilities to adopt the technology in other applications, e.g., agriculture.

  19. Investigating Second Language Acquisition.

    ERIC Educational Resources Information Center

    Jordens, Peter, Ed.; Lalleman, Josine, Ed.

    Essays in second language acquisition include: "The State of the Art in Second Language Acquisition Research" (Josine Lalleman); "Crosslinguistic Influence with Special Reference to the Acquisition of Grammar" (Michael Sharwood Smith); "Second Language Acquisition by Adult Immigrants: A Multiple Case Study of Turkish and Moroccan Learners of…

  20. Incidental Vocabulary Acquisition from Oral and Written Dialogue Journals.

    ERIC Educational Resources Information Center

    Brown, Cheryl; Sagers, Sherri L.; LaPorte, Carrie

    1999-01-01

    Presents a hypothesis-generating study of advanced university English-as-a-Foreign-Language learners' incidental vocabulary acquisition from oral and written dialogue journals over a semester. Teacher and student entries were analyzed and transcribed using WordCruncher (1993). Analyses compare characteristics of the input to the learners in the…

  1. Nuevas Adquisiciones [y] Resumenes (Recent Acquisitions and Abstracts).

    ERIC Educational Resources Information Center

    Informacion Bibliografica Educativa, 1971

    1971-01-01

    This bibliography lists over 130 publications, books, and articles recently acquired by the Colombian National Center for Documentation and Pedagogical Information concerning a variety of educational topics. The acquisitions are listed alphabetically under subject headings; publications from many countries are included. Several of the entries are…

  2. 76 FR 21809 - Defense Federal Acquisition Regulation Supplement; Technical Amendments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-19

    ... as follows: 202.1; 204.72. Updates references to the Defense Logistics Agency. 252.216-7004. Provides... 202.101 by revising the entry for ``Defense Logistics Agency'' in the definition of ``contracting... Regulation Supplement; Technical Amendments AGENCY: Defense Acquisition Regulations System, Department...

  3. A Multifunctional Hot Structure Heatshield Concept for Planetary Entry

    NASA Technical Reports Server (NTRS)

    Walker, Sandra P.; Daryabeigi, Kamran; Samareh, Jamshid A.; Wagner, Robert; Waters, Allen

    2015-01-01

    A multifunctional hot structure heatshield concept is being developed to provide technology enhancements with significant benefits compared to the current state-of-the-art heatshield technology. These benefits can potentially enable future planetary missions. The concept is unique in integrating the function of the thermal protection system with the primary load carrying structural component. An advanced carbon-carbon material system has been evaluated for the load carrying structure, which will be utilized on the outer surface of the heatshield, and thus will operate as a hot structure exposed to the severe aerodynamic heating associated with planetary entry. Flexible, highly efficient blanket insulation is sized for use underneath the hot structure to maintain required operational internal temperatures. The approach followed includes developing preliminary designs to demonstrate feasibility of the concept and benefits over a traditional, baseline design. Where prior work focused on a concept for an Earth entry vehicle, the current efforts presented here are focused on developing a generic heatshield model and performing a trade study for a Mars entry application. This trade study includes both structural and thermal evaluation. The results indicate that a hot structure concept is a feasible alternative to traditional heatshields and may offer advantages that can enable future entry missions.

  4. Space vehicle

    NASA Technical Reports Server (NTRS)

    Vonpragenau, G. L. (Inventor)

    1975-01-01

    A space vehicle having an improved ascent configuration for use in traveling in space is presented. Components of the vehicle are: (1) a winged orbiter having an elongater fuselage and rearwardly directed main engines fixed to the fuselage; (2) an elongated tank assembly of an improved configuration disposed forwardly of the fuselage and connected with the main engines of the vehicle for supplying liquid propellants; and (3) a booster stage comprising a pair of integrated solid rocket boosters connected with the orbiter immediately beneath the fuselage and extended in substantial parallelism.

  5. 32 CFR 552.35 - Rights-of-entry for survey and exploration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 3 2010-07-01 2010-07-01 true Rights-of-entry for survey and exploration. 552.35 Section 552.35 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY MILITARY RESERVATIONS AND NATIONAL CEMETERIES REGULATIONS AFFECTING MILITARY RESERVATIONS Acquisition of Real Estate and Interest Therein §...

  6. 48 CFR 552.270-9 - Inspection-Right of Entry.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 4 2012-10-01 2012-10-01 false Inspection-Right of Entry... substances; and (4) Inspecting for any current or past hazardous waste operations, to ensure that appropriate.... The purpose of this clause is to promote the ease with which the Government may inspect the...

  7. 48 CFR 552.270-9 - Inspection-Right of Entry.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Inspection-Right of Entry... substances; and (4) Inspecting for any current or past hazardous waste operations, to ensure that appropriate.... The purpose of this clause is to promote the ease with which the Government may inspect the...

  8. 48 CFR 552.270-9 - Inspection-Right of Entry.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 4 2011-10-01 2011-10-01 false Inspection-Right of Entry... substances; and (4) Inspecting for any current or past hazardous waste operations, to ensure that appropriate.... The purpose of this clause is to promote the ease with which the Government may inspect the...

  9. 48 CFR 552.270-9 - Inspection-Right of Entry.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 4 2013-10-01 2013-10-01 false Inspection-Right of Entry... substances; and (4) Inspecting for any current or past hazardous waste operations, to ensure that appropriate.... The purpose of this clause is to promote the ease with which the Government may inspect the...

  10. 48 CFR 552.270-9 - Inspection-Right of Entry.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 4 2014-10-01 2014-10-01 false Inspection-Right of Entry... substances; and (4) Inspecting for any current or past hazardous waste operations, to ensure that appropriate.... The purpose of this clause is to promote the ease with which the Government may inspect the...

  11. The Mars Science Laboratory (MSL) Entry, Descent And Landing Instrumentation (MEDLI): Hardware Performance and Data Reconstruction

    NASA Technical Reports Server (NTRS)

    Little, Alan; Bose, Deepak; Karlgaard, Chris; Munk, Michelle; Kuhl, Chris; Schoenenberger, Mark; Antill, Chuck; Verhappen, Ron; Kutty, Prasad; White, Todd

    2013-01-01

    The Mars Science Laboratory (MSL) Entry, Descent and Landing Instrumentation (MEDLI) hardware was a first-of-its-kind sensor system that gathered temperature and pressure readings on the MSL heatshield during Mars entry on August 6, 2012. MEDLI began as challenging instrumentation problem, and has been a model of collaboration across multiple NASA organizations. After the culmination of almost 6 years of effort, the sensors performed extremely well, collecting data from before atmospheric interface through parachute deploy. This paper will summarize the history of the MEDLI project and hardware development, including key lessons learned that can apply to future instrumentation efforts. MEDLI returned an unprecedented amount of high-quality engineering data from a Mars entry vehicle. We will present the performance of the 3 sensor types: pressure, temperature, and isotherm tracking, as well as the performance of the custom-built sensor support electronics. A key component throughout the MEDLI project has been the ground testing and analysis effort required to understand the returned flight data. Although data analysis is ongoing through 2013, this paper will reveal some of the early findings on the aerothermodynamic environment that MSL encountered at Mars, the response of the heatshield material to that heating environment, and the aerodynamic performance of the entry vehicle. The MEDLI data results promise to challenge our engineering assumptions and revolutionize the way we account for margins in entry vehicle design.

  12. Entry Guidance for the 2011 Mars Science Laboratory Mission

    NASA Technical Reports Server (NTRS)

    Mendeck, Gavin F.; Craig, Lynn E.

    2011-01-01

    The 2011 Mars Science Laboratory will be the first Mars mission to attempt a guided entry to safely deliver the rover to a touchdown ellipse of 25 km x 20 km. The Entry Terminal Point Controller guidance algorithm is derived from the final phase Apollo Command Module guidance and, like Apollo, modulates the bank angle to control the range flown. For application to Mars landers which must make use of the tenuous Martian atmosphere, it is critical to balance the lift of the vehicle to minimize the range error while still ensuring a safe deploy altitude. An overview of the process to generate optimized guidance settings is presented, discussing improvements made over the last nine years. Key dispersions driving deploy ellipse and altitude performance are identified. Performance sensitivities including attitude initialization error and the velocity of transition from range control to heading alignment are presented.

  13. Orbiter Return-To-Flight Entry Aeroheating

    NASA Technical Reports Server (NTRS)

    Campbell, Charles H.; Anderson, Brian; Bourland, Gary; Bouslog, Stan; Cassady, Amy; Horvath, Tom; Berry, Scott A.; Gnoffo, Peter; Wood, Bill; Reuther, James; Driver, Dave; Chao, Dennis

    2006-01-01

    The Columbia accident on February 1, 2003 began an unprecedented level of effort within the hypersonic aerothermodynamic community to support the Space Shuttle Program. During the approximately six month time frame of the primary Columbia Accident Investigation Board activity, many technical disciplines were involved in a concerted effort to reconstruct the last moments of the Columbia and her crew, and understand the critical events that led to that loss. Significant contributions to the CAIB activity were made by the hypersonic aerothermodynamic community(REF CAIB) in understanding the re-entry environments that led to the propagation of an ascent foam induced wing leading edge damage to a subsequent breech of the wing spar of Columbia, and the subsequent breakup of the vehicle. A core of the NASA hypersonic aerothermodynamics team that was involved in the CAIB investigation has been combined with the United Space Alliance and Boeing Orbiter engineering team in order to position the Space Shuttle Program with a process to perform in-flight Thermal Protection System damage assessments. This damage assessment process is now part of the baselined plan for Shuttle support, and is a direct out-growth of the Columbia accident and NASAs response. Multiple re-entry aeroheating tools are involved in this damage assessment process, many of which have been developed during the Return To Flight activity. In addition, because these aeroheating tools are part of an overall damage assessment process that also involves the thermal and stress analyses community, in addition to a much broader mission support team, an integrated process for performing the damage assessment activities has been developed by the Space Shuttle Program and the Orbiter engineering community. Several subsets of activity in the Orbiter aeroheating communities support to the Return To Flight effort have been described in previous publications (CFD?, Cavity Heating? Any BLT? Grid Generation?). This work will

  14. Robotic vehicle

    DOEpatents

    Box, W.D.

    1998-08-11

    A robotic vehicle is described for travel through a conduit. The robotic vehicle includes forward and rear housings each having a hub portion, and each being provided with surface engaging mechanisms for selectively engaging the walls of the conduit such that the housings can be selectively held in stationary positions within the conduit. The surface engaging mechanisms of each housing includes a plurality of extendible appendages, each of which is radially extendible relative to the operatively associated hub portion between a retracted position and a radially extended position. The robotic vehicle also includes at least three selectively extendible members extending between the forward and rear housings, for selectively changing the distance between the forward and rear housings to effect movement of the robotic vehicle. 20 figs.

  15. Robotic vehicle

    DOEpatents

    Box, W.D.

    1997-02-11

    A robotic vehicle is described for travel through a conduit. The robotic vehicle includes forward and rear housings each having a hub portion, and each being provided with surface engaging mechanisms for selectively engaging the walls of the conduit such that the housings can be selectively held in stationary positions within the conduit. The surface engaging mechanisms of each housing includes a plurality of extendable appendages, each of which is radially extendable relative to the operatively associated hub portion between a retracted position and a radially extended position. The robotic vehicle also includes at least three selectively extendable members extending between the forward and rear housings, for selectively changing the distance between the forward and rear housings to effect movement of the robotic vehicle. 20 figs.

  16. Robotic vehicle

    DOEpatents

    Box, W. Donald

    1998-01-01

    A robotic vehicle for travel through a conduit. The robotic vehicle includes forward and rear housings each having a hub portion, and each being provided with surface engaging mechanisms for selectively engaging the walls of the conduit such that the housings can be selectively held in stationary positions within the conduit. The surface engaging mechanisms of each housing includes a plurality of extendable appendages, each of which is radially extendable relative to the operatively associated hub portion between a retracted position and a radially extended position. The robotic vehicle also includes at least three selectively extendable members extending between the forward and rear housings, for selectively changing the distance between the forward and rear housings to effect movement of the robotic vehicle.

  17. Robotic vehicle

    DOEpatents

    Box, W. Donald

    1997-01-01

    A robotic vehicle for travel through a conduit. The robotic vehicle includes forward and rear housings each having a hub portion, and each being provided with surface engaging mechanisms for selectively engaging the walls of the conduit such that the housings can be selectively held in stationary positions within the conduit. The surface engaging mechanisms of each housing includes a plurality of extendable appendages, each of which is radially extendable relative to the operatively associated hub portion between a retracted position and a radially extended position. The robotic vehicle also includes at least three selectively extendable members extending between the forward and rear housings, for selectively changing the distance between the forward and rear housings to effect movement of the robotic vehicle.

  18. Stakeholder identification of advanced technology opportunities at international ports of entry

    SciTech Connect

    Parker, S.K.; Icerman, L.

    1997-01-01

    As part of the Advanced Technologies for International and Intermodal Ports of Entry (ATIPE) Project, a diverse group of stakeholders was engaged to help identify problems experienced at inland international border crossings, particularly those at the US-Mexican border. The fundamental issue at international ports of entry is reducing transit time through the required documentation and inspection processes. Examples of other issues or problems, typically manifested as time delays at border crossings, repeatedly mentioned by stakeholders include: (1) lack of document standardization; (2) failure to standardize inspection processes; (3) inadequate information and communications systems; (4) manual fee and tariff collection; (5) inconsistency of processes and procedures; and (6) suboptimal cooperation among governmental agencies. Most of these issues can be addressed to some extent by the development of advanced technologies with the objective of allowing ports of entry to become more efficient while being more effective. Three categories of technologies were unambiguously of high priority to port of entry stakeholders: (1) automated documentation; (2) systems integration; and (3) vehicle and cargo tracking. Together, these technologies represent many of the technical components necessary for pre-clearance of freight approaching international ports of entry. Integration of vehicle and cargo tracking systems with port of entry information and communications systems, as well as existing industry legacy systems, should further enable border crossings to be accomplished consistently with optimal processing times.

  19. Mars Science Laboratory Entry, Descent, and Landing Trajectory and Atmosphere Reconstruction

    NASA Technical Reports Server (NTRS)

    Karlgaard, Christopher D.; Kutty, Prasad; Schoenenberer, Mark; Shidner, Jeremy D.

    2013-01-01

    On August 5th 2012, The Mars Science Laboratory entry vehicle successfully entered Mars atmosphere and landed the Curiosity rover on its surface. A Kalman filter approach has been implemented to reconstruct the entry, descent, and landing trajectory based on all available data. The data sources considered in the Kalman filtering approach include the inertial measurement unit accelerations and angular rates, the terrain descent sensor, the measured landing site, orbit determination solutions for the initial conditions, and a new set of instrumentation for planetary entry reconstruction consisting of forebody pressure sensors, known as the Mars Entry Atmospheric Data System. These pressure measurements are unique for planetary entry, descent, and landing reconstruction as they enable a reconstruction of the freestream atmospheric conditions without any prior assumptions being made on the vehicle aerodynamics. Moreover, the processing of these pressure measurements in the Kalman filter approach enables the identification of atmospheric winds, which has not been accomplished in past planetary entry reconstructions. This separation of atmosphere and aerodynamics allows for aerodynamic model reconciliation and uncertainty quantification, which directly impacts future missions. This paper describes the mathematical formulation of the Kalman filtering approach, a summary of data sources and preprocessing activities, and results of the reconstruction.

  20. Orion Entry, Descent, and Landing Performance and Mission Design

    NASA Technical Reports Server (NTRS)

    Broome, Joel M.; Johnson, Wyatt

    2007-01-01

    The Orion Vehicle is the next spacecraft to take humans into space and will include missions to ISS as well as missions to the Moon. As part of that challenge, the vehicle will have to accommodate multiple mission design concepts, since return from Low Earth Orbit and return from the Moon can be quite different. Commonality between the different missions as it relates to vehicle systems, guidance capability, and operations concepts is the goal. Several unique mission design concepts include the specification of multiple land-based landing sites for a vehicle with closed-loop direct and skip entry guidance, followed by a parachute descent and landing attenuation system. This includes the ability of the vehicle to accurately target and land at a designated landing site, including site location aspects, landing site size, and landing opportunities assessments. Analyses associated with these mission design and flight performance challenges and constraints will be discussed as well as potential operational concepts to provide feasibility and/or mission commonality.

  1. Side Jet/Cross Flow Interaction at Hypersonic Re-entry Conditions

    NASA Astrophysics Data System (ADS)

    Adeli, R.; Seiler, F.

    Since decades control jets are commonly used for steering re-entry vehicles, e.g. the Apollo capsules, the Space Shuttles and were also used for the "SpaceShipOne" mission and recently direct to the flight path of missiles.

  2. 9 CFR 93.805 - Ports of entry, inspection, and treatment. 1

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., rhinoceroses, and tapirs, including regulations concerning ports of entry. (a) An elephant, hippopotamus... importer. (b) An elephant, hippopotamus, rhinoceros, or tapir shall be entered into the United States only... or the vehicle containing the animal shall be sealed by an inspector with an official seal of...

  3. 9 CFR 93.805 - Ports of entry, inspection, and treatment. 1

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., rhinoceroses, and tapirs, including regulations concerning ports of entry. (a) An elephant, hippopotamus... importer. (b) An elephant, hippopotamus, rhinoceros, or tapir shall be entered into the United States only... or the vehicle containing the animal shall be sealed by an inspector with an official seal of...

  4. 9 CFR 93.805 - Ports of entry, inspection, and treatment. 1

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., rhinoceroses, and tapirs, including regulations concerning ports of entry. (a) An elephant, hippopotamus... importer. (b) An elephant, hippopotamus, rhinoceros, or tapir shall be entered into the United States only... or the vehicle containing the animal shall be sealed by an inspector with an official seal of...

  5. 9 CFR 93.805 - Ports of entry, inspection, and treatment. 1

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., rhinoceroses, and tapirs, including regulations concerning ports of entry. (a) An elephant, hippopotamus... importer. (b) An elephant, hippopotamus, rhinoceros, or tapir shall be entered into the United States only... or the vehicle containing the animal shall be sealed by an inspector with an official seal of...

  6. Development of FIAT-Based Parametric Thermal Protection System Mass Estimating Relationships for NASA's Multi-Mission Earth Entry Concept

    NASA Technical Reports Server (NTRS)

    Sepka, Steven A.; Zarchi, Kerry; Maddock, Robert W.; Samareh, Jamshid A.

    2013-01-01

    Part of NASAs In-Space Propulsion Technology (ISPT) program is the development of the tradespace to support the design of a family of multi-mission Earth Entry Vehicles (MMEEV) to meet a wide range of mission requirements. An integrated tool called the Multi Mission System Analysis for Planetary Entry Descent and Landing or M-SAPE tool is being developed as part of Entry Vehicle Technology project under In-Space Technology program. The analysis and design of an Earth Entry Vehicle (EEV) is multidisciplinary in nature, requiring the application many disciplines. Part of M-SAPE's application required the development of parametric mass estimating relationships (MERs) to determine the vehicle's required Thermal Protection System (TPS) for safe Earth entry. For this analysis, the heat shield was assumed to be made of a constant thickness TPS. This resulting MERs will then e used to determine the pre-flight mass of the TPS. Two Mers have been developed for the vehicle forebaody. One MER was developed for PICA and the other consisting of Carbon Phenolic atop an Advanced Carbon-Carbon composition. For the the backshell, MERs have been developed for SIRCA, Acusil II, and LI-900. How these MERs were developed, the resulting equations, model limitations, and model accuracy are discussed in this poster.

  7. Interplanetary trajectory optimization of Mars aerobraking missions with constrained atmospheric entry velocities

    NASA Technical Reports Server (NTRS)

    Striepe, Scott A.; Braun, Robert D.; Powell, Richard W.; Fowler, Wallace T.

    1991-01-01

    Many current manned Mars mission studies are using low lift-to-drag ratio (L/D) vehicles to aerobrake at both Mars and earth. The use of these low L/D vehicles imposes constraints on the allowable velocity at the atmospheric interface. This paper will demonstrate that if these entry velocity constraints are incorporated into the interplanetary analysis, more opportunities can be achieved for a small increase in initial LEO mass. These additional opportunities result from varying the initial launch date, the encounter dates, and possibly using a powered Venus swingby on either the inbound or outbound transfer. This paper presents results for three atmospheric entry velocity ranges at Mars arrival and one velocity limitation upon Earth return. The results indicate that by carefully selecting the interplanetary trajectory, an optimum initial LEO mass mission can be found for even highly restrictive entry velocity missions in practically all of the 15 years studied.

  8. X-34 Vehicle Aerodynamic Characteristics

    NASA Technical Reports Server (NTRS)

    Brauckmann, Gregory J.

    1998-01-01

    The X-34, being designed and built by the Orbital Sciences Corporation, is an unmanned sub-orbital vehicle designed to be used as a flying test bed to demonstrate key vehicle and operational technologies applicable to future reusable launch vehicles. The X-34 will be air-launched from an L-1011 carrier aircraft at approximately Mach 0.7 and 38,000 feet altitude, where an onboard engine will accelerate the vehicle to speeds above Mach 7 and altitudes to 250,000 feet. An unpowered entry will follow, including an autonomous landing. The X-34 will demonstrate the ability to fly through inclement weather, land horizontally at a designated site, and have a rapid turn-around capability. A series of wind tunnel tests on scaled models was conducted in four facilities at the NASA Langley Research Center to determine the aerodynamic characteristics of the X-34. Analysis of these test results revealed that longitudinal trim could be achieved throughout the design trajectory. The maximum elevon deflection required to trim was only half of that available, leaving a margin for gust alleviation and aerodynamic coefficient uncertainty. Directional control can be achieved aerodynamically except at combined high Mach numbers and high angles of attack, where reaction control jets must be used. The X-34 landing speed, between 184 and 206 knots, is within the capabilities of the gear and tires, and the vehicle has sufficient rudder authority to control the required 30-knot crosswind.

  9. Delayed School Entry in Uganda

    ERIC Educational Resources Information Center

    Moyi, Peter

    2011-01-01

    Since 1997 Uganda has seen a large increase in school enrolment. Despite this increased enrolment, universal education has remained elusive. Many children enrol in school, but not at the recommended age, and they drop out before completing school. This article focuses on one of these problems--delayed school entry. What household factors are…

  10. Mars 2020 Entry, Descent and Landing Instrumentation (MEDLI2)

    NASA Technical Reports Server (NTRS)

    Bose, Deepak; Wright, Henry; White, Todd; Schoenenberger, Mark; Santos, Jose; Karlgaard, Chris; Kuhl, Chris; Oishi, TOmo; Trombetta, Dominic

    2016-01-01

    This paper will introduce Mars Entry Descent and Landing Instrumentation (MEDLI2) on NASA's Mars2020 mission. Mars2020 is a flagship NASA mission with science and technology objectives to help answer questions about possibility of life on Mars as well as to demonstrate technologies for future human expedition. Mars2020 is scheduled for launch in 2020. MEDLI2 is a suite of instruments embedded in the heatshield and backshell thermal protection systems of Mars2020 entry vehicle. The objectives of MEDLI2 are to gather critical aerodynamics, aerothermodynamics and TPS performance data during EDL phase of the mission. MEDLI2 builds up the success of MEDLI flight instrumentation on Mars Science Laboratory mission in 2012. MEDLI instrumentation suite measured surface pressure and TPS temperature on the heatshield during MSL entry into Mars. MEDLI data has since been used for unprecedented reconstruction of aerodynamic drag, vehicle attitude, in-situ atmospheric density, aerothermal heating, transition to turbulence, in-depth TPS performance and TPS ablation. [1,2] In addition to validating predictive models, MEDLI data has highlighted extra margin available in the MSL forebody TPS, which can potentially be used to reduce vehicle parasitic mass. MEDLI2 expands the scope of instrumentation by focusing on quantities of interest not addressed in MEDLI suite. The type the sensors are expanded and their layout on the TPS modified to meet these new objectives. The paper will provide key motivation and governing requirements that drive the choice and the implementation of the new sensor suite. The implementation considerations of sensor selection, qualification, and demonstration of minimal risk to the host mission will be described. The additional challenges associated with mechanical accommodation, electrical impact, data storage and retrieval for MEDLI2 system, which extends sensors to backshell will also be described.

  11. Language Acquisition without an Acquisition Device

    ERIC Educational Resources Information Center

    O'Grady, William

    2012-01-01

    Most explanatory work on first and second language learning assumes the primacy of the acquisition phenomenon itself, and a good deal of work has been devoted to the search for an "acquisition device" that is specific to humans, and perhaps even to language. I will consider the possibility that this strategy is misguided and that language…

  12. Modulated acquisition of spatial distortion maps.

    PubMed

    Volkov, Alexey; Gros, Jerneja Zganec; Zganec, Mario; Javornik, Tomaž; Svigelj, Aleš

    2013-01-01

    This work discusses a novel approach to image acquisition which improves the robustness of captured data required for 3D range measurements. By applying a pseudo-random code modulation to sequential acquisition of projected patterns the impact of environmental factors such as ambient light and mutual interference is significantly reduced. The proposed concept has been proven with an experimental range sensor based on the laser triangulation principle. The proposed design can potentially enhance the use of this principle to a variety of outdoor applications, such as autonomous vehicles, pedestrians' safety, collision avoidance, and many other tasks, where robust real-time distance detection in real world environment is crucial. PMID:23966196

  13. Modulated Acquisition of Spatial Distortion Maps

    PubMed Central

    Volkov, Alexey; Gros, Jerneja Žganec; Žganec, Mario; Javornik, Tomaž; Švigelj, Aleš

    2013-01-01

    This work discusses a novel approach to image acquisition which improves the robustness of captured data required for 3D range measurements. By applying a pseudo-random code modulation to sequential acquisition of projected patterns the impact of environmental factors such as ambient light and mutual interference is significantly reduced. The proposed concept has been proven with an experimental range sensor based on the laser triangulation principle. The proposed design can potentially enhance the use of this principle to a variety of outdoor applications, such as autonomous vehicles, pedestrians' safety, collision avoidance, and many other tasks, where robust real-time distance detection in real world environment is crucial. PMID:23966196

  14. Nonequilibrium effects on shock-layer radiometry during earth entry.

    NASA Technical Reports Server (NTRS)

    Arnold, J. O.; Whiting, E. E.

    1973-01-01

    Radiative enhancement factors for the CN violet and N2(+) first negative band systems caused by nonequilibrium thermochemistry in the shock layer of a blunt-nosed vehicle during earth entry are reported. The results are based on radiometric measurements obtained with the aid of a combustion-driven shock tube. The technique of converting the shock-tube measurements into predictions of the enhancement factors for the blunt-body case is described, showing it to be useful for similar applications of other shock-tube measurements.

  15. Planetary/DOD entry technology flight experiments. Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    Christensen, H. E.; Krieger, R. J.; Mcneilly, W. R.; Vetter, H. C.

    1976-01-01

    The feasibility of using the space shuttle to launch planetary and DoD entry flight experiments was examined. The results of the program are presented in two parts: (1) simulating outer planet environments during an earth entry test, the prediction of Jovian and earth radiative heating dominated environments, mission strategy, booster performance and entry vehicle design, and (2) the DoD entry test needs for the 1980's, the use of the space shuttle to meet these DoD test needs, modifications of test procedures as pertaining to the space shuttle, modifications to the space shuttle to accommodate DoD test missions and the unique capabilities of the space shuttle. The major findings of this program are summarized.

  16. Supersonic Retropropulsion Technology Development in NASA's Entry, Descent, and Landing Project

    NASA Technical Reports Server (NTRS)

    Edquist, Karl T.; Berry, Scott A.; Rhode, Matthew N.; Kelb, Bil; Korzun, Ashley; Dyakonov, Artem A.; Zarchi, Kerry A.; Schauerhamer, Daniel G.; Post, Ethan A.

    2012-01-01

    NASA's Entry, Descent, and Landing (EDL) space technology roadmap calls for new technologies to achieve human exploration of Mars in the coming decades [1]. One of those technologies, termed Supersonic Retropropulsion (SRP), involves initiation of propulsive deceleration at supersonic Mach numbers. The potential benefits afforded by SRP to improve payload mass and landing precision make the technology attractive for future EDL missions. NASA's EDL project spent two years advancing the technological maturity of SRP for Mars exploration [2-15]. This paper summarizes the technical accomplishments from the project and highlights challenges and recommendations for future SRP technology development programs. These challenges include: developing sufficiently large SRP engines for use on human-scale entry systems; testing and computationally modelling complex and unsteady SRP fluid dynamics; understanding the effects of SRP on entry vehicle stability and controllability; and demonstrating sub-scale SRP entry systems in Earth's atmosphere.

  17. 32 CFR 770.38 - Entry restrictions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... in Puerto Rico § 770.38 Entry restrictions. Except for duly authorized military personnel and... duties, entry upon any U.S. Navy installation or property in Puerto Rico at anytime, by any person...

  18. 32 CFR 770.39 - Entry procedures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ACCESS TO PARTICULAR INSTALLATIONS Entry Regulations for Naval Installations and Property in Puerto Rico... entry upon any U.S. Naval installation or property in Puerto Rico from the Commanding Officer of...

  19. 32 CFR 770.18 - Entry restrictions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... LIMITING PUBLIC ACCESS TO PARTICULAR INSTALLATIONS Base Entry Regulations for Naval Submarine Base, Bangor... the United States in the performance of their official duties, entry upon Naval Submarine Base,...

  20. 32 CFR 770.18 - Entry restrictions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... LIMITING PUBLIC ACCESS TO PARTICULAR INSTALLATIONS Base Entry Regulations for Naval Submarine Base, Bangor... the United States in the performance of their official duties, entry upon Naval Submarine Base,...

  1. 32 CFR 770.18 - Entry restrictions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... LIMITING PUBLIC ACCESS TO PARTICULAR INSTALLATIONS Base Entry Regulations for Naval Submarine Base, Bangor... the United States in the performance of their official duties, entry upon Naval Submarine Base,...

  2. 32 CFR 770.18 - Entry restrictions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... LIMITING PUBLIC ACCESS TO PARTICULAR INSTALLATIONS Base Entry Regulations for Naval Submarine Base, Bangor... the United States in the performance of their official duties, entry upon Naval Submarine Base,...

  3. 32 CFR 770.18 - Entry restrictions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... LIMITING PUBLIC ACCESS TO PARTICULAR INSTALLATIONS Base Entry Regulations for Naval Submarine Base, Bangor... the United States in the performance of their official duties, entry upon Naval Submarine Base,...

  4. An Integrated Tool for System Analysis of Sample Return Vehicles

    NASA Technical Reports Server (NTRS)

    Samareh, Jamshid A.; Maddock, Robert W.; Winski, Richard G.

    2012-01-01

    The next important step in space exploration is the return of sample materials from extraterrestrial locations to Earth for analysis. Most mission concepts that return sample material to Earth share one common element: an Earth entry vehicle. The analysis and design of entry vehicles is multidisciplinary in nature, requiring the application of mass sizing, flight mechanics, aerodynamics, aerothermodynamics, thermal analysis, structural analysis, and impact analysis tools. Integration of a multidisciplinary problem is a challenging task; the execution process and data transfer among disciplines should be automated and consistent. This paper describes an integrated analysis tool for the design and sizing of an Earth entry vehicle. The current tool includes the following disciplines: mass sizing, flight mechanics, aerodynamics, aerothermodynamics, and impact analysis tools. Python and Java languages are used for integration. Results are presented and compared with the results from previous studies.

  5. Autonomous vehicles

    SciTech Connect

    Meyrowitz, A.L.; Blidberg, D.R.; Michelson, R.C. |

    1996-08-01

    There are various kinds of autonomous vehicles (AV`s) which can operate with varying levels of autonomy. This paper is concerned with underwater, ground, and aerial vehicles operating in a fully autonomous (nonteleoperated) mode. Further, this paper deals with AV`s as a special kind of device, rather than full-scale manned vehicles operating unmanned. The distinction is one in which the AV is likely to be designed for autonomous operation rather than being adapted for it as would be the case for manned vehicles. The authors provide a survey of the technological progress that has been made in AV`s, the current research issues and approaches that are continuing that progress, and the applications which motivate this work. It should be noted that issues of control are pervasive regardless of the kind of AV being considered, but that there are special considerations in the design and operation of AV`s depending on whether the focus is on vehicles underwater, on the ground, or in the air. The authors have separated the discussion into sections treating each of these categories.

  6. The IXV vehicle model identification subsystem: Off-line estimation framework

    NASA Astrophysics Data System (ADS)

    Béjar-Romero, J. A.; Bidaux-Sokolowski, A.; Maina, S.; Preaud, J. P.

    2016-07-01

    The Intermediate eXperimental Vehicle (IXV) is an ESA re-entry technological platform built to verify in-flight the performance of critical re-entry technologies. The successful flight of the IXV provides the key elements to consolidate the knowledge necessary for the development of future European re-entry systems. The exploitation of in-flight data represents a cornerstone for this flying test bench. In this frame the IXV Vehicle Model Identification subsystem, VMI, represents those steps, techniques and algorithms that shall be applied to the collected data in order to improve the prediction capabilities for future design of re-entry vehicles and specifically to: Improve IXV flight dynamics model. Validate aerodynamic prediction methods based on Wind Tunnel Tests, WTT, and Computational Fluid Dynamics, CFD. Validate the vehicle model identification process and tools.

  7. Entry System Design Considerations for Mars Landers

    NASA Technical Reports Server (NTRS)

    Lockwood, Mary Kae; Powell, Richard W.; Graves, Claude A.; Carman, Gilbert L.

    2001-01-01

    The objective for the next generation or Mars landers is to enable a safe landing at specific locations of scientific interest. The 1st generation entry, descent and landing systems, ex. Viking and Pathfinder, provided successful landing on Mars but by design were limited to large scale, 100s of km, landing sites with minimal local hazards. The 2 nd generation landers, or smart landers, will provide scientists with access to previously unachievable landing sites by providing precision landing to less than 10 km of a target landing site, with the ability to perform local hazard avoidance, and provide hazard tolerance. This 2nd generation EDL system can be utilized for a range of robotic missions with vehicles sized for science payloads from the small 25-70 kg, Viking, Pathfinder, Mars Polar Lander and Mars Exploration Rover-class, to the large robotic Mars Sample Return, 300 kg plus, science payloads. The 2nd generation system can also be extended to a 3nd generation EDL system with pinpoint landing, 10's of meters of landing accuracy, for more capable robotic or human missions. This paper will describe the design considerations for 2nd generation landers. These landers are currently being developed by a consortium of NASA centers, government agencies, industry and academic institutions. The extension of this system and additional considerations required for a 3nd generation human mission to Mars will be described.

  8. Overview of entry risk predictions

    NASA Astrophysics Data System (ADS)

    Mrozinski, R.; Mendeck, G.; Cutri-Kohart, R.

    Risk to people on the ground from uncontrolled entries of spacecraft is a primary concern when analyzing end-of-life disposal options for satellites. Countries must balance this risk with the need to mitigate an exponentially growing space debris population. Currently the United States does this via guidelines that call for a satellite to be disposed of in a controlled manner if an uncontrolled entry would be too risky to people on the ground. This risk is measured by a quantity called "casualty expectation", or E , where casualty expectation is defined as the expectedc number of people suffering death or injury due to a spacecraft entry event. If Ec exceeds 1 in 10,000, U. S. guidelines state that the entry should be controlled rather than uncontrolled. Since this guideline can have serious impacts on the cost, lifetime, and even the mission and functionality of a satellite, it is critical that this quantity be estimated well, and decision makers understand all assumptions and limitations inherent in the resulting value. This paper discusses several issues regarding estimates of casualty expectation, beginning with an overview of relevant United States policies and guidelines. The equation the space industry typically uses to estimate casualty expectation is presented, along with a look at the sensitivity of the results to the typical assumptions, models, and initial condition uncertainties. Differences in these modeling issues with respect to launch failure Ec estimates are included in the discussion. An alternate quantity to assess risks due to spacecraft entries is introduced. "Probability of casualty", or Pc , is defined as the probability of one or more instances of people suffering death or injury due to a spacecraft entry event. The equation to estimate Pc is derived, where the same assumptions, modeling, and initial condition issues for Ec apply. Several examples are then given of both Ec and Pc estimate calculations. Due to the difficult issues in

  9. Re-Entry Guidance Using an Energy-State Equation

    NASA Astrophysics Data System (ADS)

    Abe, Akio; Shimada, Yuzo; Uchiyama, Kenji

    This paper presents a new guidance and control system for a re-entry vehicle. In the conventional drag acceleration control system employed for the present space shuttles, the velocity is an unobservable state variable and the associated pole tends to be unstable. Therefore, in this study, a condition which allows all the states to be observable is introduced using a state-space linearization method. It is also shown that energy and its rate are appropriate for the state variables. A guidance law is analytically derived on the basis of the obtained state equation with respect to the energy by solving a two-point boundary-value problem. Furthermore, a tracking control system is designed to make the position, velocity, and flight path angle of the vehicle track the reference states generated in the guidance system. Finally, numerical simulation is performed to verify the validity of the obtained plant expression, and the effectiveness of the proposed guidance and control system.

  10. Operational Use of GPS Navigation for Space Shuttle Entry

    NASA Technical Reports Server (NTRS)

    Goodman, John L.; Propst, Carolyn A.

    2008-01-01

    The STS-118 flight of the Space Shuttle Endeavour was the first shuttle mission flown with three Global Positioning System (GPS) receivers in place of the three legacy Tactical Air Navigation (TACAN) units. This marked the conclusion of a 15 year effort involving procurement, missionization, integration, and flight testing of a GPS receiver and a parallel effort to formulate and implement shuttle computer software changes to support GPS. The use of GPS data from a single receiver in parallel with TACAN during entry was successfully demonstrated by the orbiters Discovery and Atlantis during four shuttle missions in 2006 and 2007. This provided the confidence needed before flying the first all GPS, no TACAN flight with Endeavour. A significant number of lessons were learned concerning the integration of a software intensive navigation unit into a legacy avionics system. These lessons have been taken into consideration during vehicle design by other flight programs, including the vehicle that will replace the Space Shuttle, Orion.

  11. Spacecraft destruction during re-entry - latest results and development of the SCARAB software system

    NASA Astrophysics Data System (ADS)

    Lips, T.; Fritsche, B.; Koppenwallner, G.; Klinkrad, H.

    2004-01-01

    The calculation of destructive re-entries and the prediction of the related ground risk potential due to fragment objects reaching the ground have become of high interest in the past years. This was also evident during the re-entry of the MIR space station in 2001. In 1995, under ESA contract, HTG started an international cooperation with other companies and institutes to develop the SCARAB software system (Spacecraft Atmospheric Re-Entry and Aerothermal Break-Up). SCARAB is a quasi-deterministic tool, modeling a re-entry object down to sub-system level. The resulting aerodynamic parameters and mass distribution allow calculating a realistic 6D re-entry trajectory. Geometry and mass are continuously updated during calculation. Multi-level fragmentations due to different destruction processes are considered. The SCARAB software has been applied to several projects, namely ATV (ESA), ROSAT (Germany), Ariane-5 (ESA) and BeppoSAX (Italy). The practical application of SCARAB to project work has been demonstrated. In addition SCARAB has been compared with NASA's ORSAT code. It has also been verified with experimental data gained from re-entry vehicles, break-up observations and wind-tunnel tests. SCARAB is now on the way to become the European standard software for re-entry destruction analysis.

  12. Influence of interplanetary trajectory selection on Earth atmospheric entry velocity of Mars missions

    NASA Technical Reports Server (NTRS)

    Striepe, Scott A.; Braun, Robert D.; Powell, Richard W.; Fowler, Wallace T.

    1993-01-01

    Many current manned Mars mission studies are using low lift-to-drag ratio vehicles to aerobrake at both Mars and Earth. This paper will demonstrate that if entry velocity constraints are incorporated into the interplanetary analysis of aerobraking Mars missions, more opportunities can be achieved for only a small increase in initial mass in low-Earth orbit (IMLEO). These additional opportunities result from varying the initial launch date and the encounter dates and possibly using a powered Venus swingby on either the inbound or outbound transfer. This paper not only presents unconstrained entry velocity missions but also includes results for entry velocities below 12.5 and 14 km/s on Earth return and between 6.0-8.5 km/s at Mars arrival. The results indicate that, regardless of the Mars entry velocity range selected, an Earth entry velocity below 14 km/s is easily attainable for a minimal IMLEO increase. Although there are fewer 12.5 km/s Earth entry velocity missions possible, both Mars entry velocity constraint cases have over 50 percent of their missions requiring a negligible IMLEO increase.

  13. Mars Entry Atmospheric Data System Trajectory Reconstruction Algorithms and Flight Results

    NASA Technical Reports Server (NTRS)

    Karlgaard, Christopher D.; Kutty, Prasad; Schoenenberger, Mark; Shidner, Jeremy; Munk, Michelle

    2013-01-01

    The Mars Entry Atmospheric Data System is a part of the Mars Science Laboratory, Entry, Descent, and Landing Instrumentation project. These sensors are a system of seven pressure transducers linked to ports on the entry vehicle forebody to record the pressure distribution during atmospheric entry. These measured surface pressures are used to generate estimates of atmospheric quantities based on modeled surface pressure distributions. Specifically, angle of attack, angle of sideslip, dynamic pressure, Mach number, and freestream atmospheric properties are reconstructed from the measured pressures. Such data allows for the aerodynamics to become decoupled from the assumed atmospheric properties, allowing for enhanced trajectory reconstruction and performance analysis as well as an aerodynamic reconstruction, which has not been possible in past Mars entry reconstructions. This paper provides details of the data processing algorithms that are utilized for this purpose. The data processing algorithms include two approaches that have commonly been utilized in past planetary entry trajectory reconstruction, and a new approach for this application that makes use of the pressure measurements. The paper describes assessments of data quality and preprocessing, and results of the flight data reduction from atmospheric entry, which occurred on August 5th, 2012.

  14. EARLY SYNTACTIC ACQUISITION.

    ERIC Educational Resources Information Center

    KELLEY, K.L.

    THIS PAPER IS A STUDY OF A CHILD'S EARLIEST PRETRANSFORMATIONAL LANGUAGE ACQUISITION PROCESSES. A MODEL IS CONSTRUCTED BASED ON THE ASSUMPTIONS (1) THAT SYNTACTIC ACQUISITION OCCURS THROUGH THE TESTING OF HYPOTHESES REFLECTING THE INITIAL STRUCTURE OF THE ACQUISITION MECHANISM AND THE LANGUAGE DATA TO WHICH THE CHILD IS EXPOSED, AND (2) THAT…

  15. 19 CFR 122.42 - Aircraft entry.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 1 2014-04-01 2014-04-01 false Aircraft entry. 122.42 Section 122.42 Customs... AIR COMMERCE REGULATIONS Aircraft Entry and Entry Documents; Electronic Manifest Requirements for Passengers, Crew Members, and Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing...

  16. 19 CFR 122.42 - Aircraft entry.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 1 2012-04-01 2012-04-01 false Aircraft entry. 122.42 Section 122.42 Customs... AIR COMMERCE REGULATIONS Aircraft Entry and Entry Documents; Electronic Manifest Requirements for Passengers, Crew Members, and Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing...

  17. 19 CFR 122.42 - Aircraft entry.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 1 2013-04-01 2013-04-01 false Aircraft entry. 122.42 Section 122.42 Customs... AIR COMMERCE REGULATIONS Aircraft Entry and Entry Documents; Electronic Manifest Requirements for Passengers, Crew Members, and Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing...

  18. 19 CFR 122.42 - Aircraft entry.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... AIR COMMERCE REGULATIONS Aircraft Entry and Entry Documents; Electronic Manifest Requirements for Passengers, Crew Members, and Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing Within... 19 Customs Duties 1 2011-04-01 2011-04-01 false Aircraft entry. 122.42 Section 122.42...

  19. 32 CFR 770.29 - Entry procedures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 5 2012-07-01 2012-07-01 false Entry procedures. 770.29 Section 770.29 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY MISCELLANEOUS RULES RULES LIMITING PUBLIC ACCESS TO PARTICULAR INSTALLATIONS Base Entry Regulations for Naval Installations in the State of Hawaii § 770.29 Entry procedures....

  20. 19 CFR 191.143 - Drawback entry.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Drawback entry. 191.143 Section 191.143 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) DRAWBACK Foreign-Built Jet Aircraft Engines Processed in the United States § 191.143 Drawback entry. (a) Filing of entry....

  1. 10 CFR 1048.3 - Unauthorized entry.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Unauthorized entry. 1048.3 Section 1048.3 Energy DEPARTMENT OF ENERGY (GENERAL PROVISIONS) TRESPASSING ON STRATEGIC PETROLEUM RESERVE FACILITIES AND OTHER PROPERTY § 1048.3 Unauthorized entry. Unauthorized entry into or upon an SPR facility or real...

  2. 10 CFR 1048.3 - Unauthorized entry.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Unauthorized entry. 1048.3 Section 1048.3 Energy DEPARTMENT OF ENERGY (GENERAL PROVISIONS) TRESPASSING ON STRATEGIC PETROLEUM RESERVE FACILITIES AND OTHER PROPERTY § 1048.3 Unauthorized entry. Unauthorized entry into or upon an SPR facility or real...

  3. 10 CFR 1048.3 - Unauthorized entry.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Unauthorized entry. 1048.3 Section 1048.3 Energy DEPARTMENT OF ENERGY (GENERAL PROVISIONS) TRESPASSING ON STRATEGIC PETROLEUM RESERVE FACILITIES AND OTHER PROPERTY § 1048.3 Unauthorized entry. Unauthorized entry into or upon an SPR facility or real...

  4. 19 CFR 122.42 - Aircraft entry.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Aircraft entry. 122.42 Section 122.42 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY AIR COMMERCE REGULATIONS Aircraft Entry and Entry Documents; Electronic Manifest Requirements...

  5. 32 CFR 763.5 - Entry procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 5 2014-07-01 2014-07-01 false Entry procedures. 763.5 Section 763.5 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY ISLANDS UNDER NAVY JURISDICTION RULES GOVERNING PUBLIC ACCESS Entry Regulations for Kaho'olawe Island, Hawaii § 763.5 Entry procedures. (a) It is the policy of the Commander Naval...

  6. 32 CFR 763.5 - Entry procedures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 5 2012-07-01 2012-07-01 false Entry procedures. 763.5 Section 763.5 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY ISLANDS UNDER NAVY JURISDICTION RULES GOVERNING PUBLIC ACCESS Entry Regulations for Kaho'olawe Island, Hawaii § 763.5 Entry procedures. (a) It is the policy of the Commander Naval...

  7. 19 CFR 18.11 - Entry; classes of goods for which entry is authorized; form used.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 1 2012-04-01 2012-04-01 false Entry; classes of goods for which entry is authorized; form used. 18.11 Section 18.11 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF... Transportation Without Appraisement § 18.11 Entry; classes of goods for which entry is authorized; form used....

  8. 19 CFR 141.64 - Review and correction of entry and entry summary documentation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Review and correction of entry and entry summary documentation. 141.64 Section 141.64 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) ENTRY OF MERCHANDISE Presentation of Entry Papers §...

  9. Effects of Control Hysteresis on the Space Shuttle Orbiter's Entry. M.S. Thesis - George Washington Univ.

    NASA Technical Reports Server (NTRS)

    Powell, R. W.

    1975-01-01

    There are six degree-of-freedom simulations of the space shuttle orbiter entry with aerodynamic control hysteresis conducted on the NASA Langley Research Center interactive simulator known as the Automatic Reentry Flight Dynamics Simulator. These were performed to determine if the presence of aerodynamic control hysteresis would endanger the mission, either by making the vehicle unable to maintain proper attitude for a safe entry, or by increasing the amount of the reaction control system's fuel consumption beyond that carried.

  10. Small parachute flight data acquisition system

    SciTech Connect

    Ryerson, D.E.; Hauser, G.C.

    1989-01-01

    Sandia National Laboratories does extensive parachute design and testing. In support of that work, Sandia's Telemetry Department has designed and fielded a small, inexpensive data acquisition system. The system has been used in over fifty parachute and water entry tests. It consists of a microprocessor controlled unit which digitizes up to eight channels of signal-conditioned analog data and stores the data in memory for readout after the test. The system is also capable of doing control functions such as releasing the parachute at a predetermined time after unit release. 4 refs., 7 figs.

  11. TCES. Time Card Entry System

    SciTech Connect

    Montierth, B.

    1996-05-01

    The Time Card Entry System was developed for the Department of Enegy, Idaho Operations Office (DOE-ID) to interface with the DOE headquarters (DOE-HQ) Electronic Time and Attendance (ETA) system for payroll. It features pop-up window pick lists for Work Breakdown Structure numbers and Hour Codes and has extensive processing that ensures that time and attendance reported by the employee fulfills U.S. Government/OMB requirements before Timekeepers process the data at the end of the two week payroll cycle using ETA. A tour of duty profile (e.g., ten hour day, four day week with Sunday, friday and Saturday off), previously established in the ETA system, is imported into the Time Card Entry System by the timekeepers. An individual`s profile establishes the basis for validation of time of day and number of hours worked per day. At the end of the two cycle, data is exported by the timekeepers from the Time Card Entry System into ETA files.

  12. Fragmentation and ablation during entry

    SciTech Connect

    Canavan, G.H.

    1997-09-01

    This note discusses objects that both fragment and ablate during entry, using the results of previous reports to describe the velocity, pressure, and fragmentation of entering objects. It shows that the mechanisms used there to describe the breakup of non-ablating objects during deceleration remain valid for most ablating objects. It treats coupled fragmentation and ablation during entry, building on earlier models that separately discuss the entry of objects that are hard, whose high heat of ablation permits little erosion, and those who are strong whose strength prevents fragmentation, which are discussed in ``Radiation from Hard Objects,`` ``Deceleration and Radiation of Strong, Hard, Asteroids During Atmospheric Impact,`` and ``Meteor Signature Interpretation.`` This note provides a more detailed treatment of the further breakup and separation of fragments during descent. It replaces the constraint on mass per unit area used earlier to determine the altitude and magnitude of peak power radiation with a detailed analytic solution of deceleration. Model predictions are shown to be in agreement with the key features of numerical calculations of deceleration. The model equations are solved for the altitudes of maximum radiation, which agree with numerical integrations. The model is inverted analytically to infer object size and speed from measurements of peak power and altitude to provide a complete model for the approximate inversion of meteor data.

  13. Passive vs. Parachute System Architecture for Robotic Sample Return Vehicles

    NASA Technical Reports Server (NTRS)

    Maddock, Robert W.; Henning, Allen B.; Samareh, Jamshid A.

    2016-01-01

    The Multi-Mission Earth Entry Vehicle (MMEEV) is a flexible vehicle concept based on the Mars Sample Return (MSR) EEV design which can be used in the preliminary sample return mission study phase to parametrically investigate any trade space of interest to determine the best entry vehicle design approach for that particular mission concept. In addition to the trade space dimensions often considered (e.g. entry conditions, payload size and mass, vehicle size, etc.), the MMEEV trade space considers whether it might be more beneficial for the vehicle to utilize a parachute system during descent/landing or to be fully passive (i.e. not use a parachute). In order to evaluate this trade space dimension, a simplified parachute system model has been developed based on inputs such as vehicle size/mass, payload size/mass and landing requirements. This model works in conjunction with analytical approximations of a mission trade space dataset provided by the MMEEV System Analysis for Planetary EDL (M-SAPE) tool to help quantify the differences between an active (with parachute) and a passive (no parachute) vehicle concept.

  14. Analytical theories for spacecraft entry into planetary atmospheres and design of planetary probes

    NASA Astrophysics Data System (ADS)

    Saikia, Sarag J.

    flight path angles. The analytical theory is very accurate for moderate to large entry angles and for any entry speed. A new analytical theory is developed for ballistic entry at circular speed for zero initial flight path angle and for ballistic entry at circular speed for very small to large initial flight path angles. Two separate solutions for zero and non-zero initial flight path angles are needed to avoid a singularity. The classical Yaroshevskii's solution enters as the zero-order term in the solutions. Using the new solutions, other important expressions are developed such as time-of-flight, range, deceleration, and aerodynamic heating parameters (e.g. average heat input, stagnation-point heat rate, and total stagnation-point heat load). Large-scale human exploration of Mars and in situ exploration of Venus pose great challenges for entry, descent, and landing of spacecraft. The Adaptive Deployable Entry and Placement Technology (ADEPT), a mechanically deployable decelerator, presents an enabling alternative to the traditional rigid aeroshell technology. ADEPT helps in lowering the ballistic coefficient of an entry vehicle and also presents attractive options for lifting and guided entry. Optimal trajectory solutions which minimize peak deceleration and peak heat-flux are computed for four different control strategies. The deployable decelerator for human Mars missions (requiring a landed mass of 40 mt) presents an acceptable entry environment---peak heat-flux of < 80 W/cm2, and peak deceleration of less than 4 G (compared to 200 W/cm2 and 15 G for Mars Science Laboratory respectively). For lifting and guided entry for Venus in situ missions, ADEPT could lead to a two-order-of-magnitude decrease in peak deceleration and to a 50% decrease in peak heat-flux compared to conventional rigid aeroshell technology. There exist a number of attractive trajectory candidates for round-trip human missions to Mars and Venus. However, the speeds the spacecraft will encounter

  15. Robotic vehicle

    DOEpatents

    Box, W.D.

    1994-03-15

    A robotic vehicle is described for travel through an enclosed or partially enclosed conduit or pipe including vertical and/or horizontal conduit or pipe. The robotic vehicle comprises forward and rear housings each provided with a surface engaging mechanism for selectively engaging the walls of the conduit through which the vehicle is travelling, whereby the housings are selectively held in a stationary position within the conduit. The vehicle also includes at least three selectively extendable members, each of which defines a cavity therein. The forward end portion of each extendable member is secured to the forward housing and the rear end portion of each housing is secured to the rear housing. Each of the extendable members is independently extendable from a retracted position to an extended position upon the injection of a gas under pressure into the cavity of the extendable member such that the distance between the forward housing and the rear housing can be selectively increased. Further, each of the extendable members is independently retractable from the extended position to the retracted position upon the application of a vacuum to the cavity of the extendable member such that the distance between the forward housing and the rear housing can be selectively decreased. 11 figures.

  16. Robotic vehicle

    DOEpatents

    Box, W.D.

    1996-03-12

    A robotic vehicle is described for travel through an enclosed or partially enclosed conduit or pipe including vertical and/or horizontal conduit or pipe. The robotic vehicle comprises forward and rear housings each provided with a surface engaging mechanism for selectively engaging the walls of the conduit through which the vehicle is travelling, whereby the housings are selectively held in a stationary position within the conduit. The vehicle also includes at least three selectively extendable members, each of which defines a cavity therein. The forward end portion of each extendable member is secured to the forward housing and the rear end portion of each housing is secured to the rear housing. Each of the extendable members is independently extendable from a retracted position to an extended position upon the injection of a gas under pressure into the cavity of the extendable member such that the distance between the forward housing and the rear housing can be selectively increased. Further, each of the extendable members is independently retractable from the extended position to the retracted position upon the application of a vacuum to the cavity of the extendable member such that the distance between the forward housing and the rear housing can be selectively decreased. 14 figs.

  17. Robotic vehicle

    DOEpatents

    Box, W. Donald

    1996-01-01

    A robotic vehicle (10) for travel through an enclosed or partially enclosed conduit or pipe including vertical and/or horizontal conduit or pipe. The robotic vehicle (10) comprises forward and rear housings (32 and 12) each provided with a surface engaging mechanism for selectively engaging the walls of the conduit through which the vehicle is travelling, whereby the housings (32 and 12) are selectively held in a stationary position within the conduit. The vehicle (10) also includes at least three selectively extendable members (46), each of which defines a cavity (56) therein. The forward end portion (50) of each extendable member (46) is secured to the forward housing (32) and the rear end portion (48) of each housing is secured to the rear housing (12). Each of the extendable members (46) is independently extendable from a retracted position to an extended position upon the injection of a gas under pressure into the cavity (56) of the extendable member such that the distance between the forward housing (32 ) and the rear housing (12) can be selectively increased. Further, each of the extendable members (46) is independently retractable from the extended position to the retracted position upon the application of a vacuum to the cavity (56) of the extendable member (46) such that the distance between the forward housing (32) and the rear housing (12) can be selectively decreased.

  18. Robotic vehicle

    DOEpatents

    Box, W. Donald

    1994-01-01

    A robotic vehicle (10) for travel through an enclosed or partially enclosed conduit or pipe including vertical and/or horizontal conduit or pipe. The robotic vehicle (10) comprises forward and rear housings (32 and 12) each provided with a surface engaging mechanism for selectively engaging the walls of the conduit through which the vehicle is travelling, whereby the housings (32 and 12) are selectively held in a stationary position within the conduit. The vehicle (10) also includes at least three selectively extendable members (46), each of which defines a cavity (56) therein. The forward end portion (50) of each extendable member (46) is secured to the forward housing (32) and the rear end portion (48) of each housing is secured to the rear housing (12). Each of the extendable members (46) is independently extendable from a retracted position to an extended position upon the injection of a gas under pressure into the cavity (56) of the extendable member such that the distance between the forward housing (32 ) and the rear housing (12) can be selectively increased. Further, each of the extendable members (46) is independently retractable from the extended position to the retracted position upon the application of a vacuum to the cavity (56) of the extendable member (46) such that the distance between the forward housing (32) and the rear housing (12) can be selectively decreased.

  19. Physics-based Entry, Descent and Landing Risk Model

    NASA Technical Reports Server (NTRS)

    Gee, Ken; Huynh, Loc C.; Manning, Ted

    2014-01-01

    A physics-based risk model was developed to assess the risk associated with thermal protection system failures during the entry, descent and landing phase of a manned spacecraft mission. In the model, entry trajectories were computed using a three-degree-of-freedom trajectory tool, the aerothermodynamic heating environment was computed using an engineering-level computational tool and the thermal response of the TPS material was modeled using a one-dimensional thermal response tool. The model was capable of modeling the effect of micrometeoroid and orbital debris impact damage on the TPS thermal response. A Monte Carlo analysis was used to determine the effects of uncertainties in the vehicle state at Entry Interface, aerothermodynamic heating and material properties on the performance of the TPS design. The failure criterion was set as a temperature limit at the bondline between the TPS and the underlying structure. Both direct computation and response surface approaches were used to compute the risk. The model was applied to a generic manned space capsule design. The effect of material property uncertainty and MMOD damage on risk of failure were analyzed. A comparison of the direct computation and response surface approach was undertaken.

  20. Aerothermodynamic Environments Definition for the Mars Science Laboratory Entry Capsule

    NASA Technical Reports Server (NTRS)

    Edquist, Karl T.; Dyakonov, Artem A.; Wright, Michael J.; Tang, Chun Y.

    2007-01-01

    An overview of the aerothermodynamic environments definition status is presented for the Mars Science Laboratory entry vehicle. The environments are based on Navier-Stokes flowfield simulations on a candidate aeroshell geometry and worst-case entry heating trajectories. Uncertainties for the flowfield predictions are based primarily on available ground data since Mars flight data are scarce. The forebody aerothermodynamics analysis focuses on boundary layer transition and turbulent heating augmentation. Turbulent transition is expected prior to peak heating, a first for Mars entry, resulting in augmented heat flux and shear stress at the same heatshield location. Afterbody computations are also shown with and without interference effects of reaction control system thruster plumes. Including uncertainties, analysis predicts that the heatshield may experience peaks of 225 W/sq cm for turbulent heat flux, 0.32 atm for stagnation pressure, and 400 Pa for turbulent shear stress. The afterbody heat flux without thruster plume interference is predicted to be 7 W/sq cm on the backshell and 10 W/sq cm on the parachute cover. If the reaction control jets are fired near peak dynamic pressure, the heat flux at localized areas could reach as high as 76 W/sq cm on the backshell and 38 W/sq cm on the parachute cover, including uncertainties. The final flight environments used for hardware design will be updated for any changes in the aeroshell configuration, heating design trajectories, or uncertainties.