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The effect of the device upon spacecraft thermal balance, mechanical integrity and configuration, mission interference, and electrical compatibility are explored.

The new manned space exploration initiative announced by the United States in 1989 will involve the design and development of advanced manned spacecraft to transport crews from Earth orbit to the orbits of the Moon and Mars and back on a regular basis. ...Though the Moon is only a few days distant, a typical round trip to Mars will take about 500 days during which time crews will be confined to a spacecraft environment for two periods of about 235 days each. Under these exceptional circumstances, the crews must be provided with spacecraft habitability standards and accommodation facilities which are as comfortable, efficient and spacious as possible. ...Under these exceptional circumstances, the crews must be provided with spacecraft habitability standards and accommodation facilities which are as comfortable, efficient and spacious as possible.

The application of air breathing turbofan engines to a variable geometry, lifting, entry spacecraft provides a Cruise-spacecraft having increased operational flexibility. This spacecraft can accomplish a high performance, 3000 nautical mile lateral range mission, by combining the glide available from its medium hypersonic L/D (1. 7 to 2. 3) with subsonic cruise in the atmosphere. ...In this application, it excels low L/D spacecraft requiring orbit maneuvers to enhance lateral range. It is competitive with high L/D spacecraft while avoiding some of their advanced aerodynamic and thermal protection system technologies. ...It is competitive with high L/D spacecraft while avoiding some of their advanced aerodynamic and thermal protection system technologies.

The Ranger Telerobotic Flight Experiment is a highly complex teleoperated spacecraft, requiring direct human control of 36 major degrees of freedom. The University of Maryland Space Systems Laboratory and the NASA Ames Research Center are cooperating on the development of a virtual reality control station to streamline human interfaces with the Ranger spacecraft. ...The University of Maryland Space Systems Laboratory and the NASA Ames Research Center are cooperating on the development of a virtual reality control station to streamline human interfaces with the Ranger spacecraft. This describes the design and integration of the Ranger Command Chair, a system incorporating fully immersive helmet-mounted stereo displays with head tracking, hand tracking for direct positional control, and supplemental controls and displays to allow a single operator to functionally control the entire vehicle.

For the analysis of outgassing effects of spacecraft surfaces in vacuum conditions, an analyzer program package was developed as extension of the existing plume impingement model analyzer ERIMA (1)*. ...In the geometry section based on the LOHARP-VUFACT routine, the complex spacecraft surfaces are discretized. The view factors from all surface elements to pre-selected surfaces are determined considering special shading techniques In the outgassing analysis section, all surfaces are considered as sources of particle fluxes of a given outgassing rate. ...The spatial mass flow density distribution of various outgassing species is determined at numerous check points in some distance from the spacecraft.

(ADA) is developing a handheld fine water mist fire extinguisher for use on manned spacecraft and in future planetary habitats. This design employs only water and nitrogen as suppression agents to allow local refill and reuse. ...Continued development will result in prototype hardware suitable for use on future manned spacecraft.

Experience with free-flying space payloads in the current era of reduced budgets has led to a continuing need for an easier-to-use and more cost-effective capability for spacecraft thermal analyses. Preliminary thermal design of the MSX spacecraft has been developed using an 80386-based MS-DOS microcomputer. ...These programs provide both an interactive geometry editor and a graphical representation of the current spacecraft geometry. The output of VIEWI is converted to a SSPTA2 geometry input file. SSPTA, a software package that simplifies the procedures for conducting sophisticated thermal analyses of orbiting payloads, consists of CONSHAD, a view factor calculation program, SCRIPTF, a radiation conductance calculation program, ORBITAL, a satellite orbital heat flux program, and ABSORB, a program to calculate absorbed power.

The transient pressure history experienced by spacecraft during launch and ascent creates pressure differences that have to be accounted for in the mechanical design of different spacecraft components. ...The transient pressure history experienced by spacecraft during launch and ascent creates pressure differences that have to be accounted for in the mechanical design of different spacecraft components. In addition, for high power applications, the venting times must be estimated to ensure that the pressure has dropped below the critical value for corona for both ground testing and in orbit power up. ...Therefore, an accurate design tool for simulating the venting of multiple enclosures was developed. The Spacecraft Venting Simulation Software (SVSS) calculates the mass flow rates, pressures and pressure differentials for multiple interconnected compartments.

Seven hundred and sixty-three spacecraft rocket engines were flown in the program. Over 6 h of manned rocket flights were logged by the spacecraft propulsion systems and approximately one million rocket engine firings were made. ...Over 6 h of manned rocket flights were logged by the spacecraft propulsion systems and approximately one million rocket engine firings were made. One engine failure was encountered on an early unmanned flight as a result of a failure in the guidance programmer which caused the engine to operate in a manner known to cause failures.

There are not only large amounts of energy, but also many different kinds of energy in manned spacecraft, which provide chance to optimize a thermal management system in the spacecraft. When water in atmosphere in pressured cabins was removed, waste heat in atmosphere was removed synchronously.

Current studies suggest that Airborne Endospore Bioburden (AEB) may be used as an indicator of spacecraft cleanliness. AEB, as measured in closed environment air sampling under laboratory conditions and in the Environmental Control and Life Support System at Marshall Space Flight Center, has indicated that increased total counts of airborne endospores can be correlated to surface microbial contamination. ...AEB measurements have the potential to be used in monitoring surface bioburden to anticipate buildup on critical spacecraft hardware and expedite remediation.

To provide spacecraft thermal design engineers with the data needed to define the earth albedo and emission, we have analyzed data from the Earth Radiation Balance Experiment (ERBE) over a period of 36 months, covering orbital inclinations of 57 and 99 degrees.

Because MMO is spin-stabilized spacecraft, MMO requires the sun-shield and the radiator-shield in the cruise phase (Earth to Mercury) in which MMO is 3-axis stabilized, to avoid the exposure to the direct solar flux.

Cost effective design does not allow for rejection of spacecraft hardware because it cannot be inspected adequately. An actual example of an uninspectable part is presented together with its impact.

Thermal conductances are computed for relatively simple node geometries that are typical of analytical models of spacecraft. Heat-transfer rates computed with these conductances are compared to heat-transfer rates computed from exact, closed-form mathematical formulas.

A reverberant acoustic field is frequently used in ground testing when it is desired to generate a spacecraft vibration environment similar to that encountered in flight. The sound-pressure level specified to accomplish this is usually the same as the maximum expected flight fluctuating pressure level.

The software package for computerized modeling of thermal regimes of a spacecraft (S/C) provided with passive and active means of temperature control, under conditions of orbital flight mission and at thermo-vacuum testing conditions, is represented.

A novel photocatalytic oxidation technology is described for destruction of trace contaminants such as ethylene encountered in spacecraft. Results are presented of both laboratory and prototype ethylene scrubbers capable of treating 2 to 6 SCFM of contaminated humid air.

Newer concepts of thermal control coatings involving tailored optical properties are compared with the paints and coatings presently used on spacecraft. Emphasis is also given to evaluation and measurement techniques specifically dealing with the combined spatial environmental effects facility.

Water is a critical commodity for spacecraft crews, requiring extreme conservation and reclamation strategies. In addition to suppression of the immune system in spaceflight, enhancement of bacterial growth and antimicrobial resistance in weightlessness raise serious concerns regarding microbial contamination of water systems. ...We report on the combination of methods into highly sensitive, rapid technologies for detecting specific target bacteria and assessing their viability in spacecraft water.