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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 127 records · Page 7

Atmospheric environment for Space Shuttle (STS-51A) launch

Selected atmospheric conditions observed near Space Shuttle STS-51A launch time on November 8, 1984, are summarized. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere measured vertical wind profiles is reported. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-51A vehicle ascent was constructed. The STS-51A ascent atmospheric data tape is constructed to provide an internally consistent data set for use in postflight performance assessments.

Johnson, D. L.↗

Atmospheric environment for space shuttle (STS-51C) launch

Selected atmospheric conditions observed near space shuttle STS-51C launch time on January 24, 1985, at Kennedy Space Center, Florida are summarized. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere measured vertical wind profiles are presented. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-51C vehicle ascent was constructed. The STS-51C ascent atmospheric data tape was constructed to provide an internally consistent data set for use in postflight performance assessments.

Jasper, G.↗

Imaging X-ray spectrophotometric observation of SN 1006

An imaging gas scintillation proportional counter (IGSPC) at the focal plane of a grazing incidence telescope was carried aloft by a sounding rocket and used to observe soft X-ray emission from the supernova remnant SN 1006. The instrument obtained the first unambiguous detection of strong (8 + or 0.0-2 photons/sq cm s) oxygen He-alpha and Ly-alpha emission at 0.59 + or - 0.02 keV from SN 1006. This line emission is consistent with emission from a 1.8 x 10 to the 6th K plasma, although hard X-ray emission from an additional power law or a higher temperature component was also observed. The X-ray emission may be interpreted as due to either (1) a combination of blast-wave and reverse shock assuming equilibrium ionization in the plasma or (2) blast-wave emission alone with a significant degree of ionization disequilibrium.

Vartanian, M. H.↗

The Hopkins ultraviolet telescope

The Shuttle is scheduled to carry the Hopkins UV Telescope (HUT) aloft in 1986. HUT will be one of three telescopes on the mission and will be sensitive to the 450-1800 A interval. Its primary goals will be observations of Halley's Comet, the planets, distant galaxies and quasars. It will be controlled by Spacelab personnel and features a 0.9 m primary mirror, a spectrograph on the focal plane, and an Si intensified image television camera for on-line image monitoring. The main component of the spectrograph will be a 1024 channel self-scanning Reticon photodiode array coupled by optic fibers to the microchannel detector plates. HUT is presently undergoing qualification testing.

Davidsen, A. F.↗

Propelling AMPTE into orbit

Three types of propulsion - liquid, solid and cold gas - were used to get the three AMPTE (Active Magnetospheric Particle Tracer Explorers) spacecraft into their operational orbits. The booster, a thrust-augmented DELTA, placed the 1028 kg (2267 lb) international payload into a 555 km x 8.78 Re x 28.7 deg transfer orbit. Solids carried aloft by two of the spacecraft were then fired to tilt one orbit and elevate the other. Cold gas provided two of the spacecraft with torquing capabilities for attitude maneuvering. All told, it took 12 solid, 2 liquid and 2 cold gas propulsion units to get the three AMPTE spacecraft off the ground and into their operational orbits. The relationships between all of them and the manner in which they were utilized on August 16, 1984 the day of the launch - are discussed here.

Smola, J. F.↗

Atmospheric environment for space shuttle (STS-51B) launch

A summary of selected atmospheric conditions observed near space shuttle STS-51B launch time on April 29, 1985, at Kennedy Space Center Florida is presented. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere measured vertical wind profiles is given. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-51B vehicle ascent was constructed. The STS-51B ascent atmospheric data tape was constructed by Marshall Space Flight Center's Atmospheric Sciences Division to provide an internally consistent data set for use in post flight performance assessments.

Jasper, G. L.↗

Atmospheric environment for Space Shuttle (STS-51D)

A summary of selected atmospheric conditions observed near the space shuttle STS-51D launch time on April 12, 1985, at Kennedy Space Center Florida is presented. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere measured vertical wind profiles is given in this report. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-51D vehicle ascent is constructed. The STS-51D ascent atmospheric data tape is compiled by Marshall Space Flight Center's Atmospheric Sciences Division to provide an internally consistent data set for use in post-flight performance assessments.

Jasper, G. L.↗

Optical technology for flight control systems

Optical applications to the flight control system including optical data bus, sensors, and transducers are analyzed. Examples of optical data bus include airborne light optical fiber technology (ALOFT), F-5E, YA-7D, MIL-STD-1553 fiber optic data bus and NAL-optic data bus. This NAL-optic data bus is applied to STOL, and its characteristics are stressed. Principles and advantages of optical pulse-digital transducers are discussed.

Mayanagi, M.↗

Defining reclaimed water potability requirements

Water used during previous space missions has been either carried or made aloft. Future human space endeavors will probably have to utilize some form of water reclamation and recycling. There is little applied experience in either the US or foreign space programs with this technology. Water reclamation and recycling constitutes an engineering challenge of the broadest nature and will require an intensive research and development effort if this technology is to mature in time for practical use on the proposed US spacestation. In order for this to happen, reclaimed/recycled water specification will need to be devised to guide engineering development. Perhaps the most strigent specifications will involve water to be consumed. NASA's present Potable Water Specifications are not applicable to reclaimed or recycled potable water. No specifications for reclaimed or recycled potable water presently exist either inside or outside NASA. NASA's past experience with potable water systems is reviewed, limitations of the present Potable Water Specifications are examined, present world expertise with potable water reclamation/recycling systems and system analogs is reviewed, and an approach to developing pertinent Reclaimed/Recycled Potable Water Specifications for spacecraft is presented.

Janik, D. S.↗

Precipitation and kinematic structure of microburst producing storms

Single Doppler radar techniques are used to study the precipitation and kinematic structure of microburst-producing storms. Radar data collected by NCAR radars during the Joint Airport Weather Studies (JAWS) experiment are presented along with rawinsonde data taken at Denver, Colorado near the times of microburst occurrence. The radar reflectivity and velocity structure of the storms exhibited great variability, with no unique signature indicating a microburst was imminent. Detection of descending divergent flow is probably not a microburst forecasting tool, nor can the presence of rotation be used as a precursor at present. Convergent flow aloft was a prominent feature in all events. Its occurrence with a descending precipitation shaft and/or at high altitudes is a good indicator of a downdraft. It is concluded that convergent flow is a very important microburst forecasting clue, particularly when coupled with the entrainment of Theta(e) air and a dry-adiabatic lapse rate below cloud base.

Roberts, R. D.↗

Measuring Shapes of Acoustically Levitated Drops

Instrument records shadows of drops in acoustic field. Shapes of acoustically levitated liquid drops and gas bubbles examined by shadow projector. Although acoustic radiation pressure counterbalances gravitational force acting on levitated drops and bubbles, pressure usually not uniform over surfaces and causes them to assume nonspherical shapes. Shape of drop or bubble gives useful information about acoustic field and levitated material. Held aloft in laser beam by acoustic field, liquid drop casts shadow on photographic film. Changing shape of drop recorded in sequence of exposures.

Trinh, E. H.↗

Effects of Monatomic Oxygen on Coatings

Report describes tests in which paints, metals, and optical materials carried in orbit around Earth determined how monatomic oxygen in rare orbital atmosphere affects them. Specimen disks carried aloft on Space Shuttle and exposed for 41.17 h at altitude of 120 nmi (222 km).

Whitaker, Ann↗

Continuous wind measurement in the tropical Pacific using VHF radars

Very High Frequency (VHF) Radar Wind Profilers are being installed on Ponape, East Caroline Islands and Christmas Island, Republic of Kiribati to continuously monitor winds aloft. The purpose of this experiment is to study wind fluctuations on time scales between minutes and days, to determine the longitudinal character of these fluctuations, and to examine their relationship to climate variability. Six-hourly wind profiles will be provided via satellite to the scientific community for Project TOGA (Tropical Ocean Global Atmosphere).

Balsley, B. B.↗

Ground-based time-guidance algorithm for control of airplanes in a time-metered air traffic control environment: A piloted simulation study

The rapidly increasing costs of flight operations and the requirement for increased fuel conservation have made it necessary to develop more efficient ways to operate airplanes and to control air traffic for arrivals and departures to the terminal area. One concept of controlling arrival traffic through time metering has been jointly studied and evaluated by NASA and ONERA/CERT in piloted simulation tests. From time errors attained at checkpoints, airspeed and heading commands issued by air traffic control were computed by a time-guidance algorithm for the pilot to follow that would cause the airplane to cross a metering fix at a preassigned time. These tests resulted in the simulated airplane crossing a metering fix with a mean time error of 1.0 sec and a standard deviation of 16.7 sec when the time-metering algorithm was used. With mismodeled winds representing the unknown in wind-aloft forecasts and modeling form, the mean time error attained when crossing the metering fix was increased and the standard deviation remained approximately the same. The subject pilots reported that the airspeed and heading commands computed in the guidance concept were easy to follow and did not increase their work load above normal levels.

Knox, C. E.↗

Atmospheric environment for space shuttle (STS-51L) launch

A summary is given of selected atmospheric conditions observed near Space Shuttle STS-51L launch time on January 28, 1986, at Kennedy Space Center, Florida. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of pre-launch Jimsphere measured vertical wind profiles is given. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-51L vehicle ascent has been constructed. The STS-51L ascent atmospheric data tape has been constructed by Marshall Space Flight Center's Atmospheric Sciences Division to provide an internally consistent data set for use in post flight performance assessments.

Jasper, G. L.↗

Quality requirements for reclaimed/recycled water

Water used during current and previous space missions has been either carried or made aloft. Future human space endeavors will require some form of water reclamation and recycling. There is little experience in the U.S. space program with this technology. Water reclamation and recycling constitute engineering challenges of the broadest nature that will require an intensive research and development effort if this technology is to mature in time for practical use on the proposed U.S. Space Station. In order for this to happen, reclaimed/recycled water specifications will need to be devised to guide engineering development. Present NASA Potable Water Specifications are not applicable to reclaimed or recycled water. Adequate specifications for ensuring the quality of the reclaimed or recycled potable water system is reviewed, limitations of present water specifications are examined, world experience with potable water reclamation/recycling systems and systems analogs is reviewed, and an approach to developing pertinent biomedical water specifications for spacecraft is presented. Space Station water specifications should be designed to ensure the health of all likely spacecraft inhabitants including man, animals, and plants.

Janik, Daniel S.↗

Space research - At a crossroads

Efforts which must be expended if U.S. space research is to regain vitality in the next few years are discussed. Small-scale programs are the cornerstone for big science projects, giving both researchers and students a chance to practice the development of space missions and hardware and identify promising goals for larger projects. Small projects can be carried aloft by balloons, sounding rockets, the Shuttle and ELVs. It is recommended that NASA continue the development of remote sensing systems, and join with other government agencies to fund space-based materials science, space biology and medical research. Increased international cooperation in space projects is necessary for affording moderate to large scale missions, for political reasons, and to maximize available space resources. Finally, the establishment and funding of long-range goals in space, particularly the development of the infrastructure and technologies for the exploration and colonization of the planets, must be viewed as the normal outgrowth of the capabilities being developed for LEO operations.

Mcdonald, Frank B.↗

General-aviation's view of progress in the aviation weather system

For all its activity statistics, general-aviation is the most vulnerable to hazardous weather. Of concern to the general aviation industry are: (1) the slow pace of getting units of the Automated Weather Observation System (AWOS) to the field; (2) the efforts of the National Weather Service to withdraw from both the observation and dissemination roles of the aviation weather system; (3) the need for more observation points to improve the accuracy of terminal and area forecasts; (4) the need for improvements in all area forecasts, terminal forecasts, and winds aloft forecasts; (5) slow progress in cockpit weather displays; (6) the erosion of transcribed weather broadcasts (TWEB) and other deficiencies in weather information dissemination; (7) the need to push to make the Direct User Access Terminal (DUAT) a reality; and (7) the need to improve severe weather (thunderstorm) warning systems.

Lundgren, Douglas J.↗