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THE RELIABILITY OF THE SOLAR GENERATOR OF ESRO 1 IS STUDIED BY INVESTIGATING THE RELIABILITY OF ITS COMPONENTS. THE RELIABILITY IS DETERMINED FOR THE FOLLOWING COMPONENTS: DIODES, SOLAR CELLS, WIRING, AND PANELS. IT IS DEDUCED THAT THE RELIABILITY OF THE SOLAR GENERATOR DEPENDS PRINCIPALLY ON THE RELIABILITY OF THE DIODES NEAR THE HOTTEST WALLS.
Topics: CONFERENCES, PROPULSION, NUCLEAR PROPULSION, SPACECRAFT PROPULSION
337
337
Jun 19, 2010
06/10
by
Oglebay, J. C.; Turner, D. A.; Valentine, H. H
texts
eye 337
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Performance and space storage characteristics of small propane-flox upper stages
Topics: FLOX, PROPANE, SPACE STORAGE, SPACECRAFT PROPULSION, FLUORINE-LIQUID OXYGEN /FLOX/, PROPANE, SPACE...
372
372
May 6, 2010
05/10
by
Kelley, G.; Ryan, D. L
texts
eye 372
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Positive displacement injector for attitude control of spacecraft propulsion
Topics: ATTITUDE CONTROL, ATTITUDE CONTROL, DISPLACEMENT, FUEL INJECTION, SPACECRAFT PROPULSION, BELLOWS,...
172
172
Jun 1, 2011
06/11
by
Olten, Nesrin; Kraigsley, Alison; Ronney, Paul D
texts
eye 172
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Advances in polymer chemistry have led to the development of monomers and initiation agents that enable propagating free-radical polymerization fronts to exist. These fronts are driven by the exothermicity of the polymerization reaction and the transport of heat from the polymerized product to the reactant monomer/solvent/initiator solution. The thermal energy transported to the reactant solution causes the initiator to decompose, yielding free radicals, which start the free radical...
Topics: SPACECRAFT PROPULSION, MANAGEMENT PLANNING, RESEARCH MANAGEMENT, RESEARCH, GOALS, MANAGEMENT, SPACE...
548
548
Jun 21, 2010
06/10
by
Heer, E.; Yang, J.-N
texts
eye 548
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Optimization design methods for spacecraft structural systems and subsystems
Topics: MARS 71 PROJECT, SPACECRAFT INSTRUMENTS, SYSTEMS ANALYSIS, ENVIRONMENTAL TESTS, SPACECRAFT...
214
214
Jun 15, 2011
06/11
by
NON
texts
eye 214
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No Abstract Available
Topics: ELECTRIC PROPULSION, SNAP 8, SPACECRAFT PROPULSION, MAGNETOHYDRODYNAMICS, MISSION PLANNING,...
The continuing emphasis on reducing costs and downsizing spacecraft is forcing increased emphasis on reducing the subsystem mass and integration costs. For many commercial, scientific, and Department of Defense space missions, onboard propulsion is either the predominant spacecraft mass or it limits the spacecraft lifetime. Electromagnetic-pulsed-plasma thrusters (PPT's) offer the combined benefits of extremely low average electric power requirements (1 to 150 W), high specific impulse (approx....
Topics: NASA Technical Reports Server (NTRS), PULSED PLASMA THRUSTERS, WEIGHT REDUCTION, SPACECRAFT...
281
281
Jul 11, 2010
07/10
by
Diehl, J. J
texts
eye 281
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The fundamentals of the cost/performance management system used in the procurement of two tilt rotor aircraft for a joint NASA/Army research project are discussed. The contractor's reporting system and the GPO's analyses are examined. The use of this type of reporting system is assessed. Recommendations concerning the use of like systems on future projects are included.
Topics: BALLOON-BORNE INSTRUMENTS, SOLAR CELLS, QUALITY CONTROL, SPACECRAFT POWER SUPPLIES, SPACECRAFT...
211
211
Jun 2, 2011
06/11
by
Lorch, Marcus; Proctor, Seth; Lepro, Rebekah; Kafura, Dennis; Shah, Sumi
texts
eye 211
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Authorization systems today are increasingly complex. They span domains of administration, rely on many different authentication sources, and manage permissions that can be as complex as the system itself. Worse still, while there are many standards that define authentication mechanisms, the standards that address authorization are less well defined and tend to work only within homogeneous systems. This paper presents XACML, a standard access control language, as one component of a distributed...
Topics: SPACECRAFT PROPULSION, PLASMA BUBBLES, MAGNETIC DIPOLES, SOLAR WIND, MAGNETIC FIELDS, ELECTRON...
235
235
May 31, 2011
05/11
by
Bar-Itzhack, Itzhack Y.; Harman, Richard R
texts
eye 235
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This work describes two algorithms for computing the angular rate and attitude in case of a gyro and a Star Tracker failure in the Microwave Anisotropy Probe (MAP) satellite, which was placed in the L2 parking point from where it collects data to determine the origin of the universe. The nature of the problem is described, two algorithms are suggested, an observability study is carried out and real MAP data are used to determine the merit of the algorithms. It is shown that one of the...
Topics: SPACE FLIGHT, CABLES (ROPES), ROTATION, CENTRIFUGAL FORCE, PAYLOADS, LAUNCHING, SPACE STATIONS,...
417
417
May 31, 2011
05/11
by
Zwally, H. J.; Harding, D., et al; Schutz, B.; Abdalati, W.; Abshire, J.; Bentley, C.; Brenner, A.; Bufton, J.; Dezio, J.; Hancock, D.
texts
eye 417
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The Ice, Cloud and Land Elevation Satellite (ICESat) mission will measure changes in elevation of the Greenland and Antarctic ice sheets as part of NASA's Earth Observing System (EOS) of satellites. Time-series of elevation changes will enable determination of the present-day mass balance of the ice sheets, study of associations between observed ice changes and polar climate, and estimation of the present and future contributions of the ice sheets to global sea level rise. Other scientific...
Topics: FLIGHT CHARACTERISTICS, PROPULSION SYSTEM CONFIGURATIONS, SPACECRAFT PROPULSION, MARS ATMOSPHERE,...
2,177
2.2K
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eye 2,177
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Proceedings of symposium on cryogenic oxygen storage and supply systems with application to Apollo 14 spacecraft systems
Topics: INTERPLANETARY FLIGHT, JET PROPULSION, ROCKET ENGINES, ROCKET VEHICLES, PROPULSION SYSTEM...
2,389
2.4K
Jun 21, 2010
06/10
by
SISAKYAN, N. M
texts
eye 2,389
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GRAVITATIONAL AND ACCELERATION EFFECTS ON MAN AND ORGANISMS, AND BIOLOGICAL EFFECTS OF RADIATION
Topics: COMBUSTION CONTROL, PROPELLANT TANKS, SPACECRAFT PROPULSION, APOLLO SPACECRAFT, CAPILLARY TUBES,...
The goal of in-space transportation technology is to achieve within 15 years a factor of ten reduction in the cost of Earth orbital transportation and a factor of two to three reduction in propulsion system mass and travel time required for planetary missions and within 25 years to enable bold new missions to the edge of the solar system and beyond by reducing travel times by one to two orders of magnitude.
Topics: NASA Technical Reports Server (NTRS), SPACE MISSIONS, SPACE TRANSPORTATION, SPACECRAFT PROPULSION,...
517
517
Jun 13, 2011
06/11
by
Cockrell, Charles E., Jr.; Barnes, Robert S.; Belvin, Harry L.; Allmen, John; Otero, Ange
texts
eye 517
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Contributions provided by the NASA Research Centers to key Space Shuttle return-to-flight milestones, with an emphasis on debris and Thermal Protection System (TPS) damage characterization, are described herein. Several CAIB recommendations and Space Shuttle Program directives deal with the mitigation of external tank foam insulation as a debris source, including material characterization as well as potential design changes, and an understanding of Orbiter TPS material characteristics, damage...
Topics: INTERSTELLAR TRAVEL, TETHERING, ELECTRODYNAMICS, TOROIDAL PLASMAS, INTERSTELLAR MATTER,...
107
107
Jul 12, 2010
07/10
by
Chambers, A. N
texts
eye 107
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comment 0
No Abstract Available
Topics: RADIOACTIVE WASTES, SOLAR ORBITS, SPACE STORAGE, WASTE DISPOSAL, RADIATION SHIELDING, SPACE...
224
224
May 27, 2011
05/11
by
Amtmann, E.; Kimura, T.; Oyama, J.; Doden, E.; Potulski, M
texts
eye 224
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At the age of 30 days female Sprague-Dawley rats were placed on a 3.66 m radius centrifuge and subsequently exposed almost continuously for 810 days to either 2.76 or 4.15 G. An age-matched control group of rats was raised near the centrifuge facility at earth gravity. Three further control groups of rats were obtained from the animal colony and sacrificed at the age of 34, 72 and 102 days. A total of 16 variables were simultaneously factor analyzed by maximum-likelihood extraction routine and...
Topics: CONFERENCES, SPACECRAFT PROPULSION, RELATIVITY, PHYSICS, SPACE TRANSPORTATION, QUANTUM THEORY,...
229
229
May 30, 2011
05/11
by
Vickers, John H
texts
eye 229
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This paper presents a general overview of the National Center for Advanced Manufacturing, with an emphasis on Aerospace Materials, Processes and Environmental Technology. The topics include: 1) Background; 2) Mission; 3) Technology Development Approach; 4) Space Transportation Significance; 5) Partnering; 6) NCAM MAF Project; 7) NASA & Calhoun Community College; 8) Educational Development; and 9) Intelligent Synthesis Environment. This paper is presented in viewgraph form.
Topics: SPACE TRANSPORTATION, SINGLE STAGE ROCKET VEHICLES, SPACECRAFT PROPULSION, REUSABLE ROCKET ENGINES,...
447
447
Jun 2, 2011
06/11
by
Handschuh, Robert F.; Kilmain, Charles J
texts
eye 447
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An experimental and analytical comparison of the efficiency of high-speed helical gear trains is presented. Analyses of the gearing losses were conducted. Test data from a helical gear train at varying speeds and loads (to 3730 kW (5,000 hp) and 15,000 rpm) was collected. A comparison of the results indicated that the operational conditions of the gearing system affects the loss contributions of the various mechanisms and therefore the overall efficiency of the gear system.
Topics: ELECTRON RADIATION, RADIATION EFFECTS, SOLAR SAILS, SPACECRAFT CONSTRUCTION MATERIALS, SPACECRAFT...
712
712
Jul 12, 2010
07/10
by
NON
texts
eye 712
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comment 0
No Abstract Available
Topics: GEMINI SPACECRAFT, PROPULSION SYSTEM CONFIGURATIONS, SPACECRAFT PROPULSION, EQUIPMENT...
185
185
Jul 12, 2010
07/10
by
Bosch, H. B
texts
eye 185
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comment 0
No Abstract Available
Topics: LUNAR MODULE, REACTION CONTROL, SPACECRAFT PROPULSION, THERMODYNAMIC PROPERTIES, CONTROL VALVES,...
346
346
Jul 11, 2010
07/10
by
Fiduccia, C. M
texts
eye 346
favorite 0
comment 0
No Abstract Available
Topics: CHEMICAL PROPULSION, LUNAR ORBITER, SPACECRAFT PROPULSION, LIQUEFIED GASES, PAYLOADS, SATURN LAUNCH...
306
306
Jun 12, 2011
06/11
by
Sarmadi, Hengamet
texts
eye 306
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This work aims to introduce a new concept for incorporating fuzzy sets in hybrid deliberative/reactive paradigm. After a brief review on basic issues of hybrid paradigm the definition of agent-based fuzzy hybrid paradigm, which enables the agents to proceed and extract their behavior through quantitative numerical and qualitative knowledge and to impose their decision making procedure via fuzzy rule bank, is discussed. Next an example performs a more applied platform for the developed approach...
Topics: TECHNOLOGY ASSESSMENT, SPACECRAFT PROPULSION, SPACE MAINTENANCE, INTERSTELLAR TRAVEL, INTERSTELLAR...
295
295
May 31, 2011
05/11
by
Fox, David A.; Poljak, Mark D
texts
eye 295
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Unique power control technology has been incorporated into an electrical power control unit (EPCU) for the Fluids and Combustion Facility (FCF). The objective is to maximize science throughput by providing a flexible power system that is easily reconfigured by the science payload. Electrical power is at a premium on the International Space Station (ISS). The EPCU utilizes advanced power management techniques to maximize the power available to the FCF experiments. The EPCU architecture enables...
Topics: SPACECRAFT LAUNCHING, SPACECRAFT PROPULSION, SPACE FLIGHT, NASA SPACE PROGRAMS, COST REDUCTION,...
Detailed system safety guidelines/requirements were developed. Each one describes a safety measure which is suggested as a means of eliminating or reducing a particular hazard, or group of hazards, to an acceptable level, and which, if followed would tend to increase the level of safety in supplying propellants to a user in orbit. The first goal was to identify those actions that should be taken to make propellant logistics operations as safe as possible. The second was to serve as a checklist...
Topics: NASA Technical Reports Server (NTRS), CRYOGENIC ROCKET PROPELLANTS, LOGISTICS, SAFETY, SPACECRAFT...
The primary objective was to examine from a system safety viewpoint in-space propellant logistic elements and operations to define the potential hazards and to recommend means to reduce, eliminate or control them. A secondary objective was to conduct trade studies of specific systems or operations to determine the safest of alternate approaches.
Topics: NASA Technical Reports Server (NTRS), CRYOGENIC ROCKET PROPELLANTS, LOGISTICS, SAFETY,...
The objective is to develop in cooperation with other NASA centers a distributed computational environment capable of executing full 3-D aerospace propulsion applications.
Topics: NASA Technical Reports Server (NTRS), SPACECRAFT PROPULSION, COST EFFECTIVENESS, COMPUTATIONAL...
This auxiliary propulsion engine digital unit controls both the valving of the fuel and oxidizer to the engine combustion chamber and the ignition spark required for timely and efficient engine burns. In addition to this basic function, the unit is designed to manage it's own redundancy such that it is still operational after two hard circuit failures. It communicates to the data bus system several selected information points relating to the operational status of the electronics as well as the...
Topics: NASA Technical Reports Server (NTRS), AUXILIARY POWER SOURCES, BREADBOARD MODELS, SPACE SHUTTLES,...
Two thruster sizes are studied. One, a small 5-cm or 8-cm size is for spacecraft station keeping. The other, 30-cm (130 mN thrust), is for a thruster array to do primary solar electric propulsion. A 5-cm thruster (1.8 mN) has recently completed 9715 hr of life testing. Use of dished grids in the 30-cm thruster has increased beam current from 2 to 5 A. The total thrust system mass is compared for present small thrusters at different operating conditions for station keeping of synchronous...
Topics: NASA Technical Reports Server (NTRS), SPACECRAFT PROPULSION, THRUST CHAMBERS, STATIONKEEPING,...
341
341
Jul 26, 2010
07/10
by
Monge, Peter R.; Schriner, James D.; Farace, Bettie F.; Farace, Richard V
texts
eye 341
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No Abstract Available
Topics: GEOSYNCHRONOUS ORBITS, REQUIREMENTS, SPACE SHUTTLE ORBITERS, SPACE TRANSPORTATION SYSTEM,...
395
395
Jun 1, 2011
06/11
by
Kyte, Frank T
texts
eye 395
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The study of extraterrestrial matter in sediments began with the discovery of cosmic spherules during the HMS Challenger Expedition (1873-1876), but has evolved into a multidisciplinary study of the chemical, physical, and isotopic study of sediments. Extraterrestrial matter in sediments comes mainly from dust and large impactors from the asteroid belt and comets. What we know of the nature of these source materials comes from the study of stratospheric dust particles, cosmic spherules,...
Topics: SPACECRAFT PROPULSION, PHOTONIC PROPULSION, SOLAR SAILS, SPACECRAFT CONSTRUCTION MATERIALS,...
226
226
Jul 12, 2010
07/10
by
Troester, R
texts
eye 226
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comment 0
No Abstract Available
Topics: AERONAUTICAL ENGINEERING, RESEARCH AND DEVELOPMENT, COMPUTER PROGRAMS, COUNTDOWN, SPACECRAFT...
792
792
Jun 15, 2011
06/11
by
NON
texts
eye 792
favorite 0
comment 0
No Abstract Available
Topics: MARINER C SPACECRAFT, MARINER VENUS 67 SPACECRAFT, VOYAGER PROJECT, SPACECRAFT CONTROL, SPACECRAFT...
294
294
Jul 11, 2010
07/10
by
SILVERBERG, E. C
texts
eye 294
favorite 0
comment 0
No Abstract Available
Topics: PROPULSION SYSTEM CONFIGURATIONS, SPACECRAFT PROPULSION, VALVES, COMPOSITE MATERIALS, DESIGN...
435
435
Jul 12, 2010
07/10
by
Frantz, G. E
texts
eye 435
favorite 0
comment 0
No Abstract Available
Topics: APOLLO PROJECT, GROUND SUPPORT EQUIPMENT, LUNAR MODULE, SPACE VEHICLE CHECKOUT PROGRAM, SPACECRAFT...
708
708
Jul 12, 2010
07/10
by
NON
texts
eye 708
favorite 0
comment 0
No Abstract Available
Topics: APOLLO PROJECT, PROPULSION SYSTEM CONFIGURATIONS, SPACECRAFT PROPULSION, PROPULSION SYSTEM...
303
303
Jul 11, 2010
07/10
by
Hansen, L. K.; Rasor, N. S
texts
eye 303
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The thermo electronic laser energy converter (TELEC) is described and compared to the Waymouth converter and the conventional thermionic converter. The electrical output characteristics and efficiency of TELEC operation are calculated for a variety of design variables. Calculations and results are briefly outlined. It is shown that the TELEC concept can potentially convert 25 to 50 percent of incident laser radiation into electric power at high power densities and high waste heat rejection...
Topics: LASER APPLICATIONS, NASA PROGRAMS, PROJECT PLANNING, ELECTRIC POWER TRANSMISSION, ENERGY...
171
171
Jun 3, 2011
06/11
by
Gilmore, Adam; Rupp, Ti
texts
eye 171
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This paper summarizes the design process used to relieve the predicted high loads on a Space Shuttle Orbiter mechanism prior to the STS-112 flight. The overloading of the mechanism was due to a dynamic response between the orbiter and payload that was specific to this payload s mass and attachment scheme. A solution was devised by adding a component that prevented overload of the mechanism. In addition, the introduction of the new component neither interfered with the normal operation nor...
Topics: STANDARDS, TEST FACILITIES, TECHNOLOGY TRANSFER, PROPULSION SYSTEM PERFORMANCE, SPACECRAFT...
Results of a mission engineering analysis of nuclear-thermionic electric propulsion spacecraft for unmanned interplanetary and geocentric missions are summarized. Critical technologies associated with the development of nuclear electric propulsion (NEP) are assessed, along with the impact of its availability on future space programs. Outer planet and comet rendezvous mission analysis, NEP stage design for geocentric and interplanetary missions, NEP system development cost and unit costs, and...
Topics: NASA Technical Reports Server (NTRS), ELECTRIC PROPULSION, SPACECRAFT PROPULSION, THERMIONIC POWER...
The topics presented are covered in viewgraph form. The programmatic objective is to establish the feasibility of propulsion technologies for vastly expanded space activity. The technical objective is a revolutionary performance sought, such as: (1) about 1 kg/kW specific mass; (2) specific impulse tailored to mission requirements; (3) ability to use in-situ resources; (4) round-trips to Mars in months; (5) round-trips to outer planets in 1 to 2 years; and (6) the capability for robotic mission...
Topics: NASA Technical Reports Server (NTRS), ROBOTICS, SPACECRAFT PROPULSION, TECHNOLOGY ASSESSMENT,...
Current system simulations are mature, difficult to modify, and poorly documented. Probabilistic life prediction techniques for space applications are in their early application stage. Many parts of the full system, variable fidelity simulation, have been demonstrated individually or technology is available from aeronautical applications. A 20% reduction in time to design with improvements in performance and risk reduction is anticipated. GRC software development will proceed with similar...
Topics: NASA Technical Reports Server (NTRS), PREDICTION ANALYSIS TECHNIQUES, COMPUTERIZED SIMULATION,...
366
366
Jul 26, 2010
07/10
by
Chakravarthy, Sukumar R
texts
eye 366
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An essentially nonoscillatory (ENO) formulation is described for hyperbolic systems of conservation laws. ENO approaches are based on smart interpolation to avoid spurious numerical oscillations. ENO schemes are a superset of Total Variation Diminishing (TVD) schemes. In the recent past, TVD formulations were used to construct shock capturing finite difference methods. At extremum points of the solution, TVD schemes automatically reduce to being first-order accurate discretizations locally,...
Topics: LAUNCH VEHICLES, PROPULSION SYSTEM CONFIGURATIONS, PROPULSION SYSTEM PERFORMANCE, SPACECRAFT...
The contents include: 1) In-Space Transportation Goals; 2) In-Space Investment Rationale; 3) In-Space Transportation Technology Elements; 4) Space Transfer Technology Project Elements; and 5) Propellantless Propulsion Technology Project Elements.
Topics: NASA Technical Reports Server (NTRS), SPACE TRANSPORTATION, SPACECRAFT PROPULSION, ELECTRODYNAMICS,...
271
271
Jul 11, 2010
07/10
by
Fleming, W. A.; Dowman, H. W
texts
eye 271
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No Abstract Available
Topics: DEEP SPACE INSTRUMENTATION FACILITY, INTERPLANETARY FLIGHT, LUNAR EXPLORATION, RANGER PROJECT,...
921
921
Jun 15, 2011
06/11
by
NON
texts
eye 921
favorite 0
comment 0
No Abstract Available
Topics: LUNAR PROBES, SPACECRAFT CONFIGURATIONS, SURVEYOR PROJECT, SYSTEMS ANALYSIS, LAUNCH VEHICLES,...
261
261
Jul 11, 2010
07/10
by
YAKOVLEV, N. A.; ALPEROVICH, Y. A.; SKUVLOVA, N. V
texts
eye 261
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comment 0
No Abstract Available
Topics: MARS LANDING, NUCLEAR PROPULSION, NUCLEAR REACTORS, SPACECRAFT PROPULSION, NUCLEAR ELECTRIC POWER...
No abstract available
Topics: NASA Technical Reports Server (NTRS), SOLAR SAILS, SPACECRAFT PROPULSION, TECHNOLOGY ASSESSMENT,...
The objectives of the GTX (Vertical Take-off/ Horizontal Landing reusable single-stage-to-orbit system) project this viewgraph presentation summarizes include the following: (1) Determine whether or not air-breathing propulsion can enable reusable single stage to orbit vehicles; (2) Provide validated system performance data, and a baseline system design; and (3) Develop technologies applicable to high-speed airbreathing propulsion
Topics: NASA Technical Reports Server (NTRS), AIR BREATHING ENGINES, SPACECRAFT PROPULSION, SINGLE STAGE TO...
Viewgraphs on the resupply interface mechanism are presented. The major servicing activities for any major asset are normal maintenance, consumable replenishment, repair of failed components, and preplanned product improvement. Spacecraft propulsion system resupply can be divided into three major issues: design for servicing, servicing technology, and mechanization.
Topics: NASA Technical Reports Server (NTRS), REPLENISHMENT, SPACECRAFT MAINTENANCE, SPACECRAFT PROPULSION,...
An electrolysis propulsion system consumes electrical energy to decompose water into hydrogen and oxygen. These gases are stored in separate tanks and used when needed in gaseous bipropellant thrusters for spacecraft propulsion. The propellant and combustion products are clean and nontoxic. As a result, costs associated with testing, handling, and launching can be an order of magnitude lower than for conventional propulsion systems, making electrolysis a cost-effective alternative to...
Topics: NASA Technical Reports Server (NTRS), SPACECRAFT PROPULSION, ELECTROLYSIS, CLEAN FUELS, TEST...
