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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 163 records · Page 9

NASA Aircraft Safety and Operating Problems, Volume 1

The proceedings of the Conference on NASA Aircraft Safety and Operating Problems held at Langley Research Center, Hampton, Virginia, on May 4-6, 1971, are reported in this NASA Special Publication. The purpose of this conference was to discuss the results of research of the National Aeronautics and Space Administration in the field of aircraft safety and operating problems. The unclassified program components include the following: Flight Safety Airway and Runway Environment Operational Experience With Subsonic Cruise Aircraft Cockpit Environment Terminal Area Operations Flight Environment Induced Environmental Effects Contributions to this compilation were made by representatives from Ames, Flight, Langley, and Lewis Research Centers, Manned Spacecraft Center, George C. Marshall Space Flight Center, the University of Virginia, the Research Triangle Institute, and the Federal Aviation Administration .

Aircraft Safety Office↗

Modular space station phase B extension: Shuttle interface requirements

The interface requirements cover both the ground and orbital phases of operation from the launch of the first MSS module until the initial modular station has been manned and in routine operation. As a point of reference, the two-stage, fully reusable space shuttle was selected. The space shuttle is briefly described from the standpoint of its features most important to the interface requirements with the MSS. The environment induced upon the MSS elements when transported to and from orbit by the shuttle orbiter also is included. The mission operation includes the space shuttle launch facilities, the ground flow of the MSS modules, and the orbital operations of rendezvous, MSS buildup, resupply of the manned station, and orbiter descent and landing. The shuttle's once-around abort case is described as it affects the MSS interface requirements. The interfaces between the orbiter and the MSS resulting from the ground and orbital operations, are also described.

Source record↗

Apollo experience report: Lunar module landing gear subsystem

The development of the lunar module landing gear subsystem through the Apollo 11 lunar landing mission is presented. The landing gear design evolved from the design requirement, which had to satisfy the structural, mechanical, and landing performance constraints of the vehicle. Extensive analyses and tests were undertaken to verify the design adequacy. Techniques of the landing performance analysis served as a primary tool in developing the subsystem hardware and in determining the adequacy of the landing gear for toppling stability and energy absorption. The successful Apollo 11 lunar landing mission provided the first opportunity for a complete flight test of the landing gear under both natural and induced environments.

Rogers, W. F.↗

Low-temperature oxygen-plasma effects on surveyor plasmo-clay coating

The objective was to determine whether the reflectance of the degraded plasmo-clay thermal control coating could be restored by exposing it to an oxygen plasma. An experiment was conducted to determine whether bulk radiation damage would be removed by a reabsorption of oxygen ions into the pigment crystal lattice. Results show that the oxygen plasma treatment can eliminate some of the lunar environment-induced degradation on the plasmo-clay coating. Visual observations of the lunar soil on the surface after plasma treatment indicated that it was still highly absorbent to light. Therefore, part of the residual discoloration could be due to lunar soil.

Gillette, R. B.↗

Space Shuttle External Tank.

During the quarter hour of its operational life, the External Tank must provide the propellants and propellant conditioning for the Orbiter Main Engines, provide the structural support for the two Solid Rocket Boosters, withstand the natural and induced environments, and effect a safe disposal. The External Tank is twice the size of the S-II Stage used in the Saturn V Booster for the Apollo and Skylab Spacecrafts. The External Tank is 182 feet long, 27 feet in diameter, and carries 1,700,000 pounds of liquid oxygen and liquid hydrogen propellants. The Shuttle System configuration and the interaction of the system elements pose an intricate system sensitivity which must be analyzed to establish the performance and sizing requirements for the External Tank.

Zoller, L. K.↗

Skylab experiments. Volume 5: Astronomy and space physics

The astronomy and space physics investigations conducted in the Skylab program include over 20 experiments in four categories to explore space phenomena that cannot be observed from earth. The categories of space research are as follows: (1) phenomena within the solar system, such as the effect of solar energy on Earth's atmosphere, the composition of interplanetary space, the possibility of an inner planet, and the X-ray radiation from Jupiter, (2) analysis of energetic particles such as cosmic rays and neutrons in the near-earth space, (3) stellar and galactic astronomy, and (4) self-induced environment surrounding the Skylab spacecraft.

Source record↗

Payload/orbiter contamination control requirement study

The results of a contamination impact analysis upon the spacelab carrier and the spacelab carrier upon some of its potential payloads are presented. These results are based upon contamination computer modeling techniques developed to predict the induced environment for spacelab and to provide the basis for evaluation of the predicted environment against the current on orbit contamination control criteria as specified for payloads. Those spacelab carrier contamination sources evaluated against the stated contamination control criteria were outgassing/offgassing of the major nonmetallic thermal control coating of the spacelab carriers, spacelab core and experiment module and tunnel cabin atmosphere leakage, avionics bay vent, spacelab condensate vent, random particulate sloughing, and the return flux of the molecular content of these sources from the gas-gas interactions with the ambient orbital environment. It is indicated that the spacelab carrier can meet the intent of the contamination control criteria through incorporating known contamination control practices.

Bareiss, L. E.↗

The Identification of Scientific Programs to Utilize the Space Environment

A program to identify and develop ideas for scientific experimentation on the long duration exposure facility (LDEF) was completed. Four research proposals were developed: (1) Ultra pure germanium gamma ray radiation detectors in the space environment, intended to develop and demonstrate an X-ray and gamma-ray spectroscopy system incorporating a temperature cyclable high-purity germanium detector and diode heat pipe cryogenic system for cooling, (2) growth, morphogenesis and metabolism of plant embryos in the zero-gravity environment, to investigate if the space environment induces mutations in the embryogenic cells so that mutants of commercial significance with desirable attributes may be obtained, (3) effect of zero gravity on the growth and pathogenicity of selected zoopathic fungi. It is possible that new kinds of treatment for candidiasis, and tichophytosis could eventuate from the results of the proposed studies, and (4) importance of gravity to survival strategies of small animals. Gravitational effects may be direct or mediate the selection of genetic variants that are preadapted to weightlessness.

Kulacki, F. A.↗

Preliminary Shuttle payload contamination assessment

The paper discusses the molecular induced atmosphere of the Shuttle Orbiter and a payload carrier (Spacelab) configuration - long module and a 3-m pallet) in the Shuttle Orbiter payload bay and compares it to the ambient atmosphere at various orbital altitudes. The density and flux of the contaminants are expressed as a function of distance out of the payload bay for a line-of-sight perpendicular to the payload bay and payload carrier. Isodensity plots about the Shuttle Orbiter for a side and end view for each major source are presented. The major sources considered are the external surface materials mass loss, pressurized habitation area leakage, attitude control engines, and supplemental flash evaporator venting. The resulting plots provide an insight into the extent and spatial variation of the on-orbit contaminant-induced environment.

Ress, E. B.↗

Evaluation philosophy for shuttle launched payloads

Some approaches to space-shuttle payload evaluation are examined. Issues considered include subsystem replacement in low-cost modular spacecraft (LCMS), validation of spacelab payloads, the use of standard components in shuttle-era spacecraft, effects of shuttle-induced environments on payloads, and crew safety. The LCMS is described, and goals are discussed for its evaluation program. Concepts regarding how the evaluation should proceed are considered.

Heuser, R. E.↗

Silver-Teflon contamination UV radiation study

Silver-Teflon (Ag/FEP) is planned to be used as the thermal control material covering the radiator surfaces on the shuttle orbiter payload bay doors. These radiators require the use of materials that have a very low solar absorptance and a high emittance for heat rejection. However, operationally, materials used on these critical radiator surfaces, such as silver-Teflon, will be exposed to a variety of conditions which include both the natural as well as the induced environments from the Shuttle Orbiter. A complete test facility was assembled, and detailed test procedures and a test matrix were developed. Measurements of low solar absorptance were taken before and after contamination, at intervals during irradiation, and after sample cleaning to fulfill all the requirements.

Muscari, J. A.↗

Monitoring of particulate contamination and background brightness from IECM based instrumentation

Of particular concern to the astronomical community is the effect of Shuttle Transportation System induced contamination in the form of individual particles and general background on astronomical experiments. In an effort to investigate this problem, two camera/photometers in the Induced Environment Contamination Monitor (IECM) will be used to determine the size and velocity distribution of contaminant particles, their origin, and the extent of sunlit background brightness resulting from spacecraft contamination. The cameras will operate synchronously as a stereo pair to make continuous photographic measurements throughout the missions.

Clifton, K. S.↗

Space Shuttle - Now and later

The Space Shuttle System consisting of four major elements, the orbiter, three main engines, an expendable external tank, and solid rocket boosters is examined. Dimensions, thrust and payload capacity are observed, noting cost reduction through recovery and subsequent reuse of some components. Return of the solid rocket boosters (SRB's) via parachute and recovery from the ocean for refurbishment is covered. Objectives for the first mission scheduled for November 1979 include achieving a 150 nautical mile orbit and carrying a payload consisting of development flight instrumentation (DFI), the induced environment contamination monitor (IECM), and the aerodynamic coefficients identification package (ACIP). A section devoted to performance enhancement, discusses weight reduction on the orbiter, external tanks and thrust augmentation through the use of strap on solid motors (SOSM).

Malkin, M. S.↗

Collimation of high-speed flow with thermal spread losses

The operation of the neutral beam collimator designed for the mass spectrometer inlet system of the Space Shuttle Induced Environment Contamination Monitor system is discussed. The collimator will allow selective views of a 10 deg half-angle conical volume of space so that backscattered molecules from within this volume can be measured and related to the column densities of outgassing species. Gas molecules which enter the collimator but do not have a view from the entrance orifice to the exit are directed to a gas getter and eliminated. The loss of properly directed molecules in the collimator due to their thermal distribution is calculated for the case of a directed flow, which would occur when the collimator is pointed in the direction of motion of the spacecraft. Inlet to outlet flux ratios are also computed as a function of angle of attack.

Taeusch, D. R.↗

Infrared telescope on Spacelab 2

The infrared telescope (IRT) on Spacelab 2 which will be the first cryogenically cooled telescope operated from the Orbiter is discussed. Its objectives are to measure the induced environment about the Orbiter and to demonstrate the ability to manage a large volume of superfluid helium in space. The prime astrophysical objectives are to map extended sources of low surface brightness infrared emission, including the zodiacal light, the galactic plane, and extragalactic regions. The IRT design is described, including the f/4 15.2 cm highly baffled Herschelian telescope cooled to 8 K which may scan to within 35 deg of the sun. The focal plane cooled to 3 K consists of nine discrete photoconductors covering the wavelength of 4.5-120 microns in five bands, with a single stellar detector used for aspect determination. Overlapping scans, contiguous orbits, and a six degree per second scan rate permit rapid redundant coverage of 60 % of the sky.

Koch, D.↗

Interactions of surfaces with the solar plasma

The induced environment is the main source of contamination on a spacecraft. The contamination of surfaces by volatile condensable material (VCM) present on spacecraft is being studied by many investigators both in the laboratory and space. In addition to VCM, the space environment is also a contributing factor in the contamination of surfaces. The effects of the interaction of the solar plasma with surfaces is examined. Plasma particles impact at energies in the multi-kilovolt range and penetrate and become trapped in surfaces. Results show that protons can penetrate up to 600 monolayers into surfaces and reach saturation concentrations of 6%.

Mckeown, D.↗

IECM calibration and data reduction requirements

The induced environment contamination monitor (IECM) tape recorder format, as it relates to the ouput of meaningful data from the IECM instrument, is explained. Eight-bit words (or bytes) generate numbers that represent voltage levels of electronic detection probes for each experiment. This information is amalgamated by the IECM Data Acquisition and Control System (DACS). In some cases bits represent certain status situations concerning an experiment, such as whether a valve is opened or closed. Voltages are transformed into meaningful physical phenomena through equations of calibration. Data formats and plots are generated as requested for each IECM experimenter.

Wills, F. D.↗