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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 721 records · Page 40
All sourcesNASA NTRSDOE OSTI
NASA NTRS1992

STS-46 Space Shuttle mission report

The STS-46 Space Shuttle Program Mission Report contains a summary of the Orbiter, External Tank (ET), Solid Rocket Booster/Redesigned Solid Rocket Motor (SRB/RSRM), and the Space Shuttle main engine (SSME) subsystem performance during the forty-ninth flight of the Space Shuttle Program, and the twelfth flight of the Orbiter vehicle Atlantis (OV-104). In addition to the Atlantis vehicle, the flight vehicle consisted of the following: an ET, designated ET-48 (LWT-41); three SSME's, which were serial numbers 2032, 2033, and 2027 in positions 1, 2, and 3, respectively; and two SRB's which were designated BI-052. The lightweight/redesigned SRM's that were installed in each SRB were designated 360W025A for the left RSRM and 360L025B for the right RSRM. The primary objective of this flight was to successfully deploy the European Retrievable Carrier (EURECA) payload and perform the operations of the Tethered Satellite System-1 (TSS-1) and the Evaluation of Oxygen Interaction with Material 3/Thermal Energy Management Processes 2A-3 (EOIM-3/TEMP 2A-3). The secondary objectives of this flight were to perform the operations of the IMAX Cargo Bay Camera (ICBC), Consortium for Material Development in Space Complex Autonomous Payload-2 and 3 (CONCAP-2 and CONCAP-3), Limited Duration Space Environment Candidate Materials Exposure (LDCE), Pituitary Growth Hormone Cell Function (PHCF), and Ultraviolet Plume Instrumentation (UVPI). In addition to summarizing subsystem performance, this report also discusses each Orbiter, ET, SSME, SRB, and RSRM in-flight anomaly in the applicable section of the report. Also included in the discussion is a reference to the assigned tracking number as published on the Problem Tracking List. All times are given in Greenwich mean time (G.m.t.) as well as mission elapsed time (MET).

Fricke, Robert W.↗
NASA NTRS1992

STS-50 Space Shuttle mission report

The STS-50 Space Shuttle Program Mission Report contains a summary of the Orbiter, External Tank (ET), Solid Rocket Booster/Redesigned Solid Rocket Motor (SRB/RSRM), and the Space Shuttle main engine (SSME) subsystem performance during the forty-eighth flight of the Space Shuttle Program, and the twelfth flight of the Orbiter vehicle Columbia (OV-102). In addition to the Columbia vehicle, the flight vehicle consisted of the following: an ET which was designated ET-50 (LUT-43); three SSME's which were serial numbers 2019, 2031, and 2011 in positions 1, 2, and 3, respectively; and two SRB's which were designated BI-051. The lightweight/redesigned RSRM's installed in each SRB were designated 360L024A for the left RSRM and 360M024B for the right RSRM. The primary objective of the STS-50 flight was to successfully perform the planned operations of the United States Microgravity Laboratory (USML-1) payload. The secondary objectives of this flight were to perform the operations required by the Investigations into Polymer Membrane Processing (IPMP), and the Shuttle Amateur Radio Experiment 2 (SAREX-2) payloads. An additional secondary objective was to meet the requirements of the Ultraviolet Plume Instrument (UVPI), which was flown as a payload of opportunity.

Fricke, Robert W.↗
NASA NTRS1992

STS-52 Space Shuttle mission report

The STS-52 Space Shuttle Program Mission Report provides a summary of the Orbiter, External Tank (ET), Solid Rocket Booster/Redesigned Solid Rocket Motor (SRB/RSRM), and the Space Shuttle main engine (SSME) subsystem performance during the fifty-first flight of the Space Shuttle Program, and the thirteenth flight of the Orbiter vehicle Columbia (OV-102). In addition to the Orbiter, the flight vehicle consisted of the following: an ET (designated as ET-55/LWT-48); three SSME's, which were serial numbers 2030, 2015, and 2034 in positions 1, 2, and 3, respectively; and two SRB's, which were designated BI-054. The lightweight RSRM's that were installed in each SRB were designated 360L027A for the left SRB and 360Q027B for the right SRB. The primary objectives of this flight were to successfully deploy the Laser Geodynamic Satellite (LAGEOS-2) and to perform operations of the United States Microgravity Payload-1 (USMP-1). The secondary objectives of this flight were to perform the operations of the Attitude Sensor Package (ASP), the Canadian Experiments-2 (CANEX-2), the Crystals by Vapor Transport Experiment (CVTE), the Heat Pipe Performance Experiment (HPP), the Commercial Materials Dispersion Apparatus Instrumentation Technology Associates Experiments (CMIX), the Physiological System Experiment (PSE), the Commercial Protein Crystal Growth (CPCG-Block 2), the Shuttle Plume Impingement Experiment (SPIE), and the Tank Pressure Control Experiment (TPCE) payloads.

Fricke, Robert W., Jr.↗
NASA NTRS1993

DC-DC power converter research for Orbiter/Station power exchange

This project was to produce innovative DC-DC power converter concepts which are appropriate for the power exchange between the Orbiter and the Space Station Freedom (SSF). The new converters must interface three regulated power buses on SSF, which are at different voltages, with three fuel cell power buses on the Orbiter which can be at different voltages and should be tracked independently. Power exchange is to be bi-directional between the SSF and the Orbiter. The new converters must satisfy the above operational requirements with better weight, volume, efficiency, and reliability than is available from the present conventional technology. Two families of zero current DC-DC converters were developed and successfully adapted to this application. Most of the converters developed are new and are presented.

Ehsani, M.↗
NASA NTRS1992

Influence of atmospheric aerosols and desert reflectance properties on satellite radiance measurements

The influence of surface bidirectional reflectance factors, including shadowing, and of atmospheric aerosol variability are modeled for their effects on the remote sensing of desert targets from space in the 0.7-micron region at high spatial resolution. The white sand reflectance data of Salomonson (1968) are used as the basis for the simulation. The effects of the surface bi-directional reflectance and atmospheric aerosol on the nadir-normalized reflectance measured at the satellite are discussed individually and jointly. The net influence of these two factors is shown to depend on the magnitude of other parameters, such as the surface reflectance and solar zenith angle.

Bowker, D. E.↗
NASA NTRS1991

An optical approach to proximity-operations communications for Space Station Freedom

An optical communications system is described that supports bi-directional interconnections between Space Station Freedom (SSF) and a host of attached and co-orbiting platforms. These proximity-operations (Prox-Ops) platforms are categorized by their maximum distance from SSF, with several remaining inside 1-km range and several extending out to 37-km and 2000-km ranges in the initial and growth phases, respectively. Two distinct Prox-Ops optical terminals are described. A 1-cm-aperture system is used on the short-range platforms to reduce payload mass, and a 10-cm-aperture system is used on the long-range platforms and on SSF to support the optical link budgets. The system supports up to four simultaneous user links, by assigning wavelengths to the various platforms and by using separate SSF terminals for each link.

Marshalek, Robert G.↗
NASA NTRS1991

GaAs monolithic R.F. modules for SARSAT distress beacons

Monolithic GaAs UHF components for use in SARSAT Emergency Distress beacons are under development by Microwave Monolithics, Inc., Simi Valley, CA. The components include a bi-phase modulator, driver amplifier, and a 5 watt power amplifier.

Cauley, Michael A.↗
NASA NTRS1992

Giant suppression of flux-flow resistivity in heavy-ion irradiated Tl2Ba2Ca2Cu3O10 films - Influence of linear defects on vortex transport

A large shift of the onset of flux-flow resistivity and the irreversibility line H(irr)(T) to higher temperatures is observed in Tl2Ba2Ca2Cu3O10 films containing linear defects created by Ag(+21) ion irradiation. The H(irr)(T), which has a characteristic L shape in highly anisotropic Tl and Bi based cuprates, becomes more like that of YBa2Cu3O7 in the presence of these defects. The Jc at 77 K also shows a large increase as a result of flux localization at the defects. The transport data indicate that in the H-T plane above H(irr)(T) of the unirradiated material, an ensemble of unoccupied defects is required for effective pinning of each flux line in the system.

Budhani, R. C.↗
NASA NTRS1993

Self-consistent electrostatic potential due to trapped plasma in the magnetosphere

A steady state solution for the self-consistent electrostatic potential due to a plasma confined in a magnetic flux tube is considered. A steady state distribution function is constructed for the trapped particles from the constants of the motion, in the absence of waves and collisions. Using Liouville's theorem, the particle density along the geomagnetic field is determined and found to depend on the local magnetic field, self-consistent electric potential, and the equatorial plasma distribution function. A hot anisotropic magnetospheric plasma in steady state is modeled by a bi-Maxwellian at the equator. The self-consistent electric potential along the magnetic field is calculated assuming quasineutrality, and the potential drop is found to be approximately equal to the average kinetic energy of the equatorially trapped plasma. The potential is compared with that obtained by Alfven and Faelthammar (1963).

Miller, Ronald H.↗
NASA NTRS1983

Improved fabrication techniques for infrared bolometers

Techniques are described for producing improved infrared bolometers from doped germanium. Ion implantation and sputter metalization have been used to make ohmic electrical contacts to Ge:Ga chips. This method results in a high yield of small monolithic bolometers with very little low-frequency noise. When one of these chips is used as the thermometric element of a composite bolometer, it must be bonded to a dielectric substrate. The thermal resistance of the conventional epoxy bond has been measured and found to be undesirably large. A procedure for soldering the chip to a metalized portion of the substrate is described which reduced this resistance. The contribution of the metal film absorber to the heat capacity of a composite bolometer has been measured. The heat capacity of a NiCr absorber at 1.3 K can dominate the bolometer performance. A Bi absorber has significantly lower heat capacity. A low temperature blackbody calibrator has been built to measure the optical responsivity of bolometers. A composite bolometer system with a throughput of approx. 0.1 sr sq cm was constructed using the new techniques. In negligible background it has an optical NEP of 3.6 10((exp -15) W/sq root of Hz at 1.0 K with a time constant of 20 ms. The noise in this bolometer is white above 2.5 Hz and is somewhat below the value predicted by thermodynamic equilibrium theory. It is in agreement with calculations based on a recent nonequilibrium theory.

Lange, A. E.↗
NASA NTRS1990

NOVA: A new multi-level logic simulator

A new logic simulator that was developed at the NASA Space Engineering Research Center for VLSI Design was described. The simulator is multi-level, being able to simulate from the switch level through the functional model level. NOVA is currently in the Beta test phase and was used to simulate chips designed for the NASA Space Station and the Explorer missions. A new algorithm was devised to simulate bi-directional pass transistors and a preliminary version of the algorithm is presented. The usage of functional models in NOVA is also described and performance figures are presented.

Miles, L.↗
NASA NTRS1993

Specification and testing for power by wire aircraft

A power by wire aircraft is one in which all active functions other than propulsion are implemented electrically. Other nomenclature are 'all electric airplane,' or 'more electric airplane.' What is involved is the task of developing and certifying electrical equipment to replace existing hydraulics and pneumatics. When such functions, however, are primary flight controls which are implemented electrically, new requirements are imposed that were not anticipated by existing power system designs. Standards of particular impact are the requirements of ultra-high reliability, high peak transient bi-directional power flow, and immunity to electromagnetic interference and lightning. Not only must the electromagnetic immunity of the total system be verifiable, but box level tests and meaningful system models must be established to allow system evaluation. This paper discusses some of the problems, the system modifications involved, and early results in establishing wiring harness and interface susceptibility requirements.

Hansen, Irving G.↗
NASA NTRS1991

Low cost high efficiency GaAs monolithic RF module for SARSAT distress beacons

Low cost high performance (5 Watts output) 406 MHz beacons are urgently needed to realize the maximum utilization of the Search and Rescue Satellite-Aided Tracking (SARSAT) system spearheaded in the U.S. by NASA. Although current technology can produce beacons meeting the output power requirement, power consumption is high due to the low efficiency of available transmitters. Field performance is currently unsatisfactory due to the lack of safe and reliable high density batteries capable of operation at -40 C. Low cost production is also a crucial but elusive requirement for the ultimate wide scale utilization of this system. Microwave Monolithics Incorporated (MMInc.) has proposed to make both the technical and cost goals for the SARSAT beacon attainable by developing a monolithic GaAs chip set for the RF module. This chip set consists of a high efficiency power amplifier and a bi-phase modulator. In addition to implementing the RF module in Monolithic Microwave Integrated Circuit (MMIC) form to minimize ultimate production costs, the power amplifier has a power-added efficiency nearly twice that attained with current commercial technology. A distress beacon built using this RF module chip set will be significantly smaller in size and lighter in weight due to a smaller battery requirement, since the 406 MHz signal source and the digital controller have far lower power consumption compared to the 5 watt power amplifier. All the program tasks have been successfully completed. The GaAs MMIC RF module chip set has been designed to be compatible with the present 406 MHz signal source and digital controller. A complete high performance low cost SARSAT beacon can be realized with only additional minor iteration and systems integration.

Petersen, W. C.↗
NASA NTRS1993

Dynamics of adaptive structures: Design through simulations

The use of a helical bi-morph actuator/sensor concept by mimicking the change of helical waveform in bacterial flagella is perhaps the first application of bacterial motions (living species) to longitudinal deployment of space structures. However, no dynamical considerations were analyzed to explain the waveform change mechanisms. The objective is to review various deployment concepts from the dynamics point of view and introduce the dynamical considerations from the outset as part of design considerations. Specifically, the impact of the incorporation of the combined static mechanisms and dynamic design considerations on the deployment performance during the reconfiguration stage is studied in terms of improved controllability, maneuvering duration, and joint singularity index. It is shown that intermediate configurations during articulations play an important role for improved joint mechanisms design and overall structural deployability.

Park, K. C.↗
NASA NTRS1993

STS-53 Space Shuttle mission report

The STS-53 Space Shuttle Program Mission Report provides a summary of the Orbiter, External Tank (ET), Solid Rocket Booster/Redesigned Solid Rocket Motor (SRB/RSRM), and the Space Shuttle Main Engine (SSME) subsystems performance during the fifty-second flight of the Space Shuttle Program, and the fifteenth flight of the Orbiter vehicle Discovery (OV-103). In addition to the Orbiter, the flight vehicle consisted of an ET, which was designated as ET-49/LWT-42; three SSME's, which were serial numbers 2024, 2012, and 2017 in positions 1, 2, and 3, respectively; and two SRB's, which were designated BI-055. The lightweight RSRM's that were installed in each SRB were designated 360L028A for the left SRB, and 360L028B for the right SRB. The primary objective of this flight was to successfully deploy the Department of Defense 1 (DOD-1) payload. The secondary objectives of this flight were to perform the operations required by the Glow Experiment/Cryogenic Heat Pipe Experiment Payload (GCP); the Hand-Held, Earth-Oriented, Real-Time, Cooperative, User-Friendly, Location-Targeting and Environmental System (HERCULES); the Space Tissue Loss (STL); the Battlefield Laser Acquisition Sensor Test (BLAST); the Radiation Monitoring Equipment-III (RME-III); the Microcapsules in Space-1 (MIS-1); the Visual Function Tester-2 (VFT-2); the Cosmic Radiation Effects and Activation Monitor (CREAM); the Clouds Logic to Optimize Use of Defense Systems-1A (CLOUDS-1A); the Fluids Acquisition and Resupply Experiment (FARE); and the Orbital Debris Radar Calibration Spheres (ODERACS). In addition to presenting a summary of subsystem performance, this report also discusses each Orbiter, ET, SSME, SRB, and RSRM in-flight anomaly in the applicable section of the report. Listed in the discussion of each anomaly is the officially assigned tracking number as published by each Project Office in their respective Problem Tracking List. All times given in this report are in Greenwich mean time (G.m.t.) as well as mission elapsed time (MET).

Fricke, Robert W., Jr.↗
NASA NTRS1993

STS-54 Space Shuttle mission report

The STS-54 Space Shuttle Program Mission Report is a summary of the Orbiter, External Tank (ET), Solid Rocket Booster/Redesigned Solid Rocket Motor (SRB/RSRM), and the Space Shuttle Main Engine (SSME) subsystems performance during this fifty-third flight of the Space Shuttle Program, and the third flight of the Orbiter vehicle Endeavour (OV-105). In addition to the Orbiter, the flight vehicle consisted of an ET, which was designated ET-51; three SSME's, which were serial numbers 2019, 2033, and 2018 in positions 1, 2, and 3, respectively; and two retrievable and reusable SRB's which were designated BI-056. The lightweight RSRM's that were installed in each SRB were designated 360L029A for the left SRB, and 360L029B for the right SRB. The primary objectives of this flight were to perform the operations to deploy the Tracking and Data Relay Satellite-F/Inertial Upper Stage payload and to fulfill the requirements of the Diffuse X-Ray Spectrometer (DXS) payload. The secondary objective was to fly the Chromosome and Plant Cell Division in Space (CHROMEX), Commercial Generic Bioprocessing Apparatus (CGBA), Physiological and Anatomical Rodent Experiment (PARE), and the Solid Surface Combustion Experiment (SSCE). In addition to presenting a summary of subsystem performance, this report also discusses each Orbiter, ET, SSME, SRB, and RSRM in-flight anomaly in the applicable section of the report. The official tracking number for each in-flight anomaly, assigned by the cognizant project, is also shown. All times are given in Greenwich mean time (G.m.t.) and mission elapsed time (MET).

Fricke, Robert W., Jr.↗
NASA NTRS1993

Efficient management of cardiovascular risk screening programs

The Environmental Health Unit, located on-site at the the Goddard Space Flight Center (GSFC), is responsible for the implementation of the Center's Employee Environmental and Occupational Health Program. The Health Unit, Health Physics (HP), and Industrial Hygiene (IH) staffs collaborate to provide quality service to the employees at GSFC. The Health Unit staff identifies, evaluates, and ensures the control of occupational hazards on the Center. In the past, components of the Industrial Hygiene Program have included the Industrial Hygiene Health Hazard Identification Program (IHHIP), the Hearing Conservation Program (HCP), the Hazard Communication Program, and the bi-annual fume hood survey. More recently, the Environmental Health Unit has expanded its services by adding the Ergonomics Program. Various aspects of the Ergonomics Program are discussed.

Roth, Carol↗
NASA NTRS1992

Flight 20 (STS-45) polysulfide gas path investigation

This report documents the results of the investigation into causes of gas paths on the 20A and 20B case-to-nozzle joints on STS-42. The investigation was conducted by the Investigation Board appointed by the senior vice president and general manager of Space Operations, Mr. R. E. Lindstrom, on 7 Feb. 1992. The probability of gas path occurrence in the nozzle-to-case-joint polysulfide had been identified during joint redesign. However, actual flight gas path incidence has been limited to RSRM-11 and the 20A and 20B segments. The blow-by condition on the 20A segment was a first time occurrence which was a special concern. The investigation covered all technical aspects associated with the gas path and blow-by conditions: materials and processing history, design requirements and as-built compliance to the design, thermal and structural analyses, computer modeling, and laboratory experimentation with the materials involved. The investigation was coordinated with Mr. Ken Jones at NASA Marshall in bi-weekly teleconferences. The Board also supported Dr. James C. Blair's independent NASA investigation team by providing copies of collected data, conducting requested analyses, and supporting several all-day teleconferences to provide understanding and resolve issues. The Dr. Blair support requirement was successfully concluded on 4 Mar. 1992.

Bjorkman, Rey C.↗