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Hill, C. K.

Publications and source records attributed to Hill, C. K..

At least 19 records

Natural environment application for NASP-X-30 design and mission planning

The NASA/MSFC Mission Analysis Program has recently been utilized in various National Aero-Space Plane (NASP) mission and operational planning scenarios. This paper focuses on presenting various atmospheric constraint statistics based on assumed NASP mission phases using established natural environment design, parametric, threshold values. Probabilities of no-go are calculated using atmospheric parameters such as temperature, humidity, density altitude, peak/steady-state winds, cloud cover/ceiling, thunderstorms, and precipitation. The program although developed to evaluate test or operational missions after flight constraints have been established, can provide valuable information in the design phase of the NASP X-30 program. Inputting the design values as flight constraints the Mission Analysis Program returns the probability of no-go, or launch delay, by hour by month. This output tells the X-30 program manager whether the design values are stringent enough to meet his required test flight schedules.

Johnson, D. L.

Wind models for the NSTS ascent trajectory biasing for wind load alleviation

New concepts are presented for aerospace vehicle ascent wind profile biasing. The purpose for wind biasing the ascent trajectory is to provide ascent wind loads relief and thus decrease the probability for launch delays due to wind loads exceeding critical limits. Wind biasing trajectories to the profile of monthly mean winds have been widely used for this purpose. The wind profile models presented give additional alternatives for wind biased trajectories. They are derived from the properties of the bivariate normal probability function using the available wind statistical parameters for the launch site. The analytical expressions are presented to permit generalizations. Specific examples are given to illustrate the procedures. The wind profile models can be used to establish the ascent trajectory steering commands to guide the vehicle through the first stage. For the National Space Transportation System (NSTS) program these steering commands are called I-loads.

Smith, O. E.

Winds aloft statistical analysis in support of day of launch Shuttle systems evaluation

In connection with the development of the Meteorological Interactive Data Display System (MIDDS) for utilization by the Launch Systems Evaluation Advisory Team (LSEAT), requirements have been established to expand the pre-launch analysis of winds aloft for the Space Shuttle. Statistical analyses developed for the system include: comparison of pre-launch wind component profiles to wind component extremes at each altitude calculated from launch site historical data; conditional probability ellipses for wind vectors at a future time given the wind vector at an initial time; comparison of observed extreme wind shear and associated wind speed with launch site historical data utilizing the bivariate extreme value (Gumbel) distribution; estimation of extremes of wind speed or wind shear at a future time given the extremes of either variable at an initial time, utilizing the conditional extreme value distribution; power spectrum analysis for tracking wind perturbation energy in sequential pre-launch Jimsphere wind profiles.

Adelfang, S. I.

Spacelab 3: Research in microgravity

The Spacelab 3 mission, which focused on research in microgravity, took place during the period April 29 through May 6, 1985. Spacelab 3 was the second flight of the National Aeronautics and Space Administration's modular Shuttle-borne research facility. An overview of the mission is presented. Preliminary scientific results from the mission were presented by investigators at a symposium held at Marshall Space Flight Center on December 4, 1985. This special issue is based on reports presented at that symposium.

Fichtl, G. H.

Analysis of Jimsphere pairs for use in assessing Space Vehicle ascent capability

A data base of paired detailed wind profiles was developed for use in evaluating Shuttle Transportation System (STS) ascent capability. Since launch decision is based on a wind measured about 3.5 hr before launch, a data base of paired detailed profiles is needed. Method and technique on the reduction process and analysis is also presented. Guidelines used in selecting the pairs of profiles were established to insure a valid and representative data base. Sigma-U values for 3.5 hr at 12 km altitude show 8 percent increase from the transition case to the winter case and 18 percent decrease from the transition case to the summer case. Sigma-Values for 3.5 hr at 12 km altitude shows 12 percent increase from the transition case to the winter case and 17 percent decrease from the transition case to the summer case. A special feature of the 7- and 10.5-hr cases is that sigma-V increases by as much as 30 percent from the transition to the winter profiles. This large increase does not appear in the sigma-U data. Comparisons of the calculated values of 3.5 hr standard deviations of U and V with actual component deviations measured during space shuttle launch conditions confirm that the statistical values are representative.

Hill, C. K.

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.

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.

Spacelab 3 mission - Broadening horizons in space research

The Spacelab 3 mission involves research in materials sciences, fluid mechanics, atmospheric science, astrophysics, and life sciences with emphasis on materials sciences. In this regard the mission will provide the best low-gravity environment possible within the hardware and operational constraints of the Shuttle/Spacelab system. This is truly a major milestone in space research. The paper describes the scientific goals of this important Spacelab mission and discusses how the mission was planned relative to the low-gravity aspects of the mission.

Fichtl, G. H.

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-41G) launch

Selected atmospheric conditions that were observed near Space Shuttle STS-41G launch time on October 5, 1984 at Kennedy Space Center in Florida are summarized. Values of ambient pressure, temperature, moisture, ground winds, visual obsrvations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere-measured vertical wind profiles is given. The final atmospheric tape consisting of wind and thermodynamic parameters versus altitude for STS-41G vehicle ascent was constructed. The STS-41G ascent atmospheric data tape was constructed. The STS-41G 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.

Johnson, D. L.

Atmospheric environment for Space Shuttle (STS-41D) launch

Selected atmospheric conditions observed near Space Shuttle STS-41D launch time on August 30, 1984, 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 is given as well as wind and thermodynamic parameters representative of surface and aloft conditions in the SRB descent/impact ocean area. Final atmospheric tapes, which consist of wind and thermodynamic parameters versus altitude, for STS-41D vehicle ascent and SRB descent/impact were constructed. The STS-41D ascent meteorological data tape was constructed by Marshall Space Flight Center's Atmospheric Science Division to provide an internally consistent data set for use in post flight performance assessments.

Johnson, D. L.

Atmospheric environment for Space Shuttle (STS-11) launch

Atmospheric conditions observed near Space Shuttle STS-11 launch time on February 3, 1984, 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 reported. Wind and thermodynamic parameters representative of surface and aloft conditions in the SRB descent/impact ocean area are presented. Meteorological tapes, which consist of wind and thermodynamic parameters vesus altitude, for STS-11 vehicle ascent and SRB descent/impact were constructed.

Johnson, D. L.

Atmospheric environment for space shuttle (STS-13) launch

Selected atmospheric conditions observed near Space Shuttle STS-13 launch time on April 6, 1984, 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 is given. The final meteorological tape, which consists of wind and thermodynamic parameters versus altitude, for STS-13 vehicle ascent was constructed by Marshall Space Flight Center in response to shuttle task agreement No. 561-81-22-368 with Johnson Space Center.

Johnson, D. L.

Atmospheric environment for Space Shuttle (STS-9) launch

This report presents a summary of selected atmospheric conditions observed near Space Shuttle STS-9 launch time on November 28, 1983, at Kennedy Space Center, Florida. 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 meteorological tape, which consists of wind and thermodynamic parameters versus altitude, for STS-9 vehicle ascent has been constructed. The STS-9 ascent meteorological data tape has been constructed by Marshall Space Flight Center in response to Shuttle task agreement No. 561-81-22-368 with Johnson Space Center.

Johnson, D. L.

Atmospheric environment for space shuttle (STS-8) launch

Selected atmospheric conditions observed near Space Shuttle STS-8 launch time on August 30, 1983, 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 is given. Also presented are wind and thermodynamic parameters representative of surface and aloft conditions in the SRB descent/impact ocean area. Final meteorological tapes, which consist of wind and thermodynamic parameters versus altitude, for STS-8 vehicle ascent and SRB descent/impact were constructed. The STS-8 ascent meteorological data tape was constructed.

Johnson, D. L.

Atmospheric environment for Space Shuttle (STS-7) launch

Selected atmospheric conditions observed near Space Shuttle STS-7 launch time on June 18, 1983, 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 is given in this report. Also presented are wind and thermodynamic parameters representative of surface and aloft conditions in the SRB descent/impact ocean area. Final meteorological tapes, which consist of wind and thermodynamic parameters versus altitude, for STS-7 vehicle ascent and Acoustic/SRB descent have been constructed. The STS-7 ascent meteorological data tape has been constructed by Marshall Space Flight Center in response to Shuttle task agreement No. 936-53-22-368 with Johnson Space Center.

Johnson, D. L.

NASA's AVE/VAS program

A discussion is presented concerning the Atmospheric Variability Experiment (AVE) which was conducted during the spring of 1982 as part of NASA's Visible and Infrared Spin-Scan Radiometer (VISSR) Atmospheric Sounder (VAS) demonstration. The AVE/VAS Ground Truth Field Experiment is examined in detail, which comprised the obtaining of rawinsonde observations during various meteorological conditions on four different days when VAS data were obtained. These experiments were performed over 24 hr periods in a mesoscale network of 24 National Weather Service rawinsonde sites and 13 NASA and NOAA special sites. The VAS, operating as a part of the GOES satellite system, was employed to provide two-dimensional cloud mapping capability during each of the AVE/VAS experiment periods. Among the goals of this AVE/VAS program, in addition to management of the acquisition and processing of the data, were to perform the research and development needed to produce data products from VAS radiances, to validate the data, and to assess the impact of the data on mesoscale meteorological forecasting and research requirements.

Hill, C. K.