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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 181 records · Page 10
All sourcesNASA NTRSDOE OSTI
NASA NTRS1976

Modular thrust subsystem approaches to solar electric propulsion module design

Three approaches are presented for packaging the elements of a 30 cm ion thrustor subsystem into a modular thrust subsystem. The individual modules, when integrated into a conceptual solar electric propulsion module are applicable to a multimission set of interplanetary flights with the Space Shuttle/Interim Upper Stage as the launch vehicle. The emphasis is on the structural and thermal integration of the components into the modular thrust subsystems. Thermal control for the power processing units is either by direct radiation through louvers in combination with heat pipes of an all heat pipe system. The propellant storage and feed system and thrustor gimbal system concepts are presented. The three approaches are compared on the basis of mass, cost, testing, interfaces, simplicity, reliability, and maintainability.

Cake, J. E.↗
NASA NTRS1977

Radiative metallic thermal protection systems - A status report

During the early stages of the space shuttle program there were a number of technological uncertainties concerning the applicability of metallic thermal protection systems (TPS) to the multimission environment of the shuttle. To resolve the uncertainties and to advance the state-of-the-art, the NASA-Langley Research Center initiated a broad-based technology program to develop metallic TPS over the temperature range from 810 K to 1590 K. Wind tunnel tests conducted to assess the influence of surface/stream interaction of wavy surfaces on the design of metallic TPS indicate small increases in heat flux and surface drag for flow angles less than 20 deg. Analytical and experimental investigations, recently completed, have significantly improved prediction methods for cyclic creep behavior of TPS components repeatedly exposed to complex mission cycles. Thermal/structural concept optimization studies to minimize mass while maintaining structural integrity have led to advanced designs with unit masses which are competitive with those for shuttle RSI. In addition, the durability and reusability of metallic TPS have been repeatedly demonstrated in tests of full-scale systems. The current state-of-the-art strongly suggests that radiative metallic TPS have come of age.

Bohon, H. L.↗
NASA NTRS1977

NASA's standard spacecraft for free flying shuttle payloads

The paper gives a detailed description of the Multimission Modular Spacecraft. Attention is given to the structural system, the electrical system, the thermal control system, the power system, attitude control, the propulsion module, and mission considerations.

Bartlett, R. O.↗
NASA NTRS1977

Ion engine auxiliary propulsion applications and integration study

The benefits derived from application of the 8-cm mercury electron bombardment ion thruster were assessed. Two specific spacecraft missions were studied. A thruster was tested to provide additional needed information on its efflux characteristics and interactive effects. A Users Manual was then prepared describing how to integrate the thruster for auxiliary propulsion on geosynchronous satellites. By incorporating ion engines on an advanced communications mission, the weight available for added payload increases by about 82 kg (181 lb) for a 100 kg (2200 lb) satellite which otherwise uses electrothermal hydrazine. Ion engines can be integrated into a high performance propulsion module that is compatible with the multimission modular spacecraft and can be used for both geosynchronous and low earth orbit applications. The low disturbance torques introduced by the ion engines permit accurate spacecraft pointing with the payload in operation during thrusting periods. The feasibility of using the thruster's neutralizer assembly for neutralization of differentially charged spacecraft surfaces at geosynchronous altitude was demonstrated during the testing program.

S. Zafran↗
NASA NTRS1976

Severe storms observing satellite (STORMSAT)

The primary payload for this satellite is the Advanced Atmospheric Sounding and Imaging Radiometer which will perform precise infrared temperature sounding and visible/infrared imaging from geostationary orbit. A secondary payload instrument which may be utilized on STORMSAT is the Microwave Atmospheric Sounding Radiometer which provides an independent set of temperature and humidity sounding in cloudy, meteorologically active regions. The study provides satellite designs and identifies mission-unique subsystems using the Multimission Modular Spacecraft using a Shuttle/Interim Upper Stage launch vehicle.

Source record↗
NASA NTRS1977

Toward a new V/STOL generation

While many V/STOL problems are now better understood and technology has progressed to the point where higher thrust/weight ratios and greater stability augmentation are achievable, a number of still existing insufficiencies provide a sobering reminder that learning in ground testing and simulation, and careful methodical planning, are a prerequisite for any research and development program. The present paper is centered on the major technical problems for the Navy Type multimission V/STOL aircraft. The aircraft's configurations with and without forward lift fan are discussed, along with the propulsion systems, testing techniques, controls, displays, flight dynamics, and ground/flow field interactions.

Roberts, L.↗
NASA NTRS1978

Overview of the large space systems technology program

A multicenter management approach which provides the opportunity to work across many disciplines and match the roles and expertise of various NASA facilities is described for the large space system technology (LSST) program which was established to define, develop, and verify structural concepts, analyses, and design procedures for a range of sizes and configurations to be deployed, erected, or fabricated in orbit during projected space missions utilizing shuttle in the 1985 to 2000 time period. Benefits from the program include reduced costs for transporting structures having low mass, high packageability, and multimission capabilities. Technologies identified by the LSST program will contribute to the solutions of problems in other sectors of the economy.

Guastaferro, A.↗
NASA NTRS1978

Ion propulsion cost effectivity

Ion propulsion modules employing 8-cm thrusters and 30-cm thrusters were studied for Multimission Modular Spacecraft (MMS) applications. Recurring and nonrecurring cost elements were generated for these modules. As a result, ion propulsion cost drivers were identified to be Shuttle charges, solar array, power processing, and thruster costs. Cost effective design approaches included short length module configurations, array power sharing, operation at reduced thruster input power, simplified power processing units, and power processor output switching. The MMS mission model employed indicated that nonrecurring costs have to be shared with other programs unless the mission model grows. Extended performance missions exhibited the greatest benefits when compared with monopropellant hydrazine propulsion.

Zafran, S.↗
NASA NTRS1978

Reflections on the NASA standardization effort

The NASA standardization effort which has been in existence for four years is described. A significant number of equipments have been declared standard in order to achieve multimission utilization with the consequent avoidance of high nonrecurring development costs. The small numbers of equipments and significant gaps in time before the next user requires the item raise questions of the value of maintaining a standard, how to assure its producibility economically in the future, and how to prevent its technical obsolescence. Increasing pressures to broaden the participation of industry in the space program have also contributed to a reexamination of the philosophy of standardization.

Sonnemann, H.↗
NASA NTRS1978

Efficient payload processing - The opposite side of frequent Space Shuttle launches

An overview is presented of the processing cycles of horizontally integrated and vertically integrated Shuttle payloads at the Kennedy Space Center. Attention is given to the integration of these payloads into Shuttle-ready cargos and the installation of the cargo into the Orbiter. Diagrams are presented of: (1) Shuttle processing flow at KSC, (2) payload processing flow, (3) typical items of multimission support equipment, (4) primary items of checkout equipment, (5) payload ready for transfer into the canister for vertical processing, and (6) the rotating service structure retracted to receive the payload canister.

Scherer, L. R.↗
NASA NTRS1978

Cryogenic cooling for spacecraft sensors, instruments, and experiments

Several disciplines requiring in-space cryogenic cooling are identified including high-energy, gamma-ray, and IR astronomy, relativity missions, and superconducting devices. Radiant coolers are limited in terms of temperature ranges and cooling loads. Other spacecraft cryogenic systems include stored solid cryogenic coolers using materials such as hydrogen, neon, argon, and methane. Two such cooler designs are described including one for the Nimbus F limb radiance inversion radiometer and one for the Nimbus G limb infrared monitoring of the atmosphere. Suggestions for increasing the performance of solid cryogenic coolers are made, such as a multimission cooler, a mechanical refrigerator, Stirling-cycle refrigerators, and Vuilleumier mechanized coolers. Techniques for obtaining cryogenic cooling in the milli-K range are identified as dilution refrigeration and adiabatic demagnetization.

Sherman, A.↗
NASA NTRS1977

NASA standard communications and data handling subsystem

The paper gives a functional description and discusses hardware implementation for the Communication and Data Handling (C&DH) subsystem of the Multimission Modular Spacecraft. The C&DH subsystem: (1) provides the command and telemetry link between the spacecraft and the terrestrial system, (2) distributes commands to and collects telemetry from all spacecraft systems via a duplex serial multiplex data bus and remote interface units, and (3) contains onboard computation capability. The C&DH is a single 4 x 4 x 1-1/2 foot module; the stuffed module weighs 270 lbs including 60 lbs of mission unique weight. The hardware is versatile and cost effective, and its modular structure permits repair, refurbishment, and even modification/updating in space

Robinson, D. L.↗
NASA NTRS1978

Landsat-D - A systems overview

Landsat D, scheduled for launch in 1981, is designed to be a complete end-to-end highly automated data gathering and processing system providing a major step forward in global remote sensing for earth resources applications. This paper discusses the major components of the flight segment (the Multimission Modular Spacecraft, the Thematic Mapper and the Multispectral Scanner Subsystem) and of the ground segment (the Data Management System and the Landsat-D Assessment System). Descriptions and diagrams illustrating various aspects of flight and ground segments are provided.

Salomonson, V. V.↗
NASA NTRS1979

Space transportation, satellite services, and space platforms

The paper takes a preview of the progressive development of vehicles for space transportation, satellite services, and orbital platforms. A low-thrust upper stage of either the ion engine or chemical type will be developed to transport large spacecraft and space platforms to and from GEO. The multimission spacecraft, space telescope, and other scientific platforms will require orbital serves going beyond that provided by the Shuttle's remote manipulator system, and plans call for extravehicular activity tools, improved remote manipulators, and a remote manned work station (the cherry picker).

Disher, J. H.↗
NASA NTRS1979

Synchronous orbit power technology needs

An attempt is made to define the needs for future geosynchronous spacecraft power subsystem components, including power generation, energy storage, and power processing. Three projected models (a mission model, an orbit transfer vehicle model, and a mass model) for power subsystem components are used to define power requirements and mass limitations for future spacecraft. Based upon these models, the power subsystems for a 10-kW, 10-year-life, dedicated spacecraft and for a 20-kW, 20-year-life multimission platform are analyzed to establish power density requirements for orbit transfer vehicles. Comparison of these requirements to state-of-the-art (Intelsat 5) design values shows that major improvements, by a factor of 2 or more, are needed to accomplish the near term missions.

Slifer, L. W., Jr.↗
NASA NTRS1978

The NASA Standard Telemetry and Command Components /STACC/

The Standard Telemetry and Command Components (STACC) were conceived by NASA for use on the Multimission Modular Spacecraft. The components have wider application, however, and already are being considered for many other spacecraft. A programmable Central Unit controls Remote Interface Units via a full duplex data bus, providing data acquisition and command distribution capability throughout the spacecraft. The Central Unit can meet any uplink, time code, and format requirements without hardware changes. Each remote unit can acquire any type of data (serial digital, bi-level, analog, or passive analog) on any channel. A third type of unit is an optional interface providing I/O capability to an on-board computer. The protocols used on the 1Mbps data bus are compatible with MSFC's 'Standard Interfaces for Digital Data, Multiplex Serial Data Acquisition and Distribution Systems (SIDD/MSDADS Standard)'. The bus design saves significant harness weight and simplifies the single point ground and isolation approaches.

Elliott, N. P.↗
NASA NTRS1978

Packet telemetry - A possible standard protocol for spacecraft data handling

Packetized telemetry-handling offers an opportunity to standardize major portions of the spacecraft-to-ground interface for future NASA missions. An end-to-end packet transport protocol is proposed which enables delivery of telemetry data from a remote space sensor to a ground-based user with virtually no project-unique intermediate processing. This paper reviews the possibility of creating a single telemetry format standard for both deep-space and near-earth missions. The proposed standard addresses the greatest NASA problem of the coming decade - cost - by allowing telemetry streams from many inflight spacecraft to be handled on the ground by common, simple, multimission processing elements.

Greenberg, E.↗