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Susko, Michael

Publications and source records attributed to Susko, Michael.

Comparison of Satellite-Derived Wind Measurements with Other Wind Measurement Sensors

The purpose of this paper is to compare the good data from the Jimsphere launches with the data from the satellite system. By comparing the wind speeds from the Fixed Pedestal System 16 (FPS-16) Radar/Jimsphere Wind System and NASA's 50-MHz Radar Wind Profiler, the validation of winds from Geostationary Operational Environmental Satellite 7 (GOES-7) is performed. This study provides an in situ data quality check for the GOES-7 satellite winds. Comparison was made of the flowfields in the troposphere and the lower stratosphere of case studies of pairs of Jimsphere balloon releases and Radar Wind Profiler winds during Space Shuttle launches. The mean and standard deviation of the zonal component statistics, the meridional component statistics, and the power spectral density curves show good agreement between the two wind sensors. The standard deviation of the u and v components for the STS-37 launch (consisting of five Jimsphere/Radar Wind Profiler data sets) was 1.92 and 1.67 m/s, respectively; for the STS-43 launch (there were six Jimsphere/Wind Profiler data sets) it was 1.39 and 1.44 m/s, respectively. The overall standard deviation was 1.66 m/s for the u component and 1.55 m/s tor the v component, and a standard deviation of 2.27 m/s tor the vector wind difference. The global comparison of satellite with Jimsphere balloon vector winds shows a standard deviation of 3.15 m/s for STS-43 and 4.37 m/s for STS-37. The overall standard deviation of the vector wind was 3.76 m/s, with a root-mean-square vector difference of 4.43 m/s. These data have demonstrated that this unique comparison of the Jimsphere and satellite winds provides excellent ground truth and a frame of reference during testing and validation of satellite data

Susko, Michael↗

Comparison of FPS-16 radar/jimsphere and NASA's 50-MHz radar wind profiler turbulence indicators

Measurements of the wind and turbulent regions from the surface to 16 km by the FPS-11 radar/jimsphere system are reported with particular attention given to the use of these turbulence and wind assessments to validate the NASA 50-MHz radar wind profiler. Wind profile statistics were compared at 150-m wavelengths, a wavelength validated from 20 jimspheres, simultaneously tracked by FPS-16 and FPQ-14 radar, and the resulting analysis of auto spectra, cross-spectra, and coherence squared spectra of the wind profiles. Results demonstrate that the NASA prototype wind profiler is an excellent monitoring device illustrating the measurements of the winds within 1/2 hour of launch zero.

Susko, Michael↗

Turbulence indicators for Space Shuttle launches

A report on the research and analysis for identifying turbulent regions from the surface to 16 km for Space Shuttle launches is presented. The research demonstrates that the results from the FPS-16 radar/jimsphere balloon system in measuring winds can indicate the presence of or conditions ripe for turbulence in the troposphere and lower stratosphere. It is shown that atmospheric data obtained during the Shuttle launches by the rawinsonde in conjunction with the jimsphere provide the necessary meteorological data to compute aerodynamic parameters to identify turbulence.

Susko, Michael↗

Atmospheric turbulence review of space shuttle launches

Research and analysis on the identification of turbulent regions from the surface to 16 km during Space Shuttle launches are discussed. It was demonstrated that the results from the FPS-16 radar/jimsphere balloon system in measuring winds can indeed indicate the presence or conditions ripe for turbulence in the troposphere and lower stratosphere. It was further demonstrated that atmospheric data obtained during the shuttle launches by the rawinsonde in conjunction with the jimsphere provides the necessary meteorological data to compute aerodynamic parameters to identify turbulence, such as Reynolds number drag coefficient, turbulent stresses, total energy, stability parameter, vertical gradient of kinetic energy, Richardson number, and the turbulence probability index. Enhanced temperature lapse rates and inversion rates, strong vector wind shears, and large changes in wind direction identify the occurrence of turbulence at the troposphere. When any two of the above conditions occur simultaneously, a significant probability of turbulence can occur.

Susko, Michael↗

Space Shuttle externally induced environment compared with Skylab's natural environment

Electret measurements obtained of the particulate contamination environment within the Space Shuttle Orbiter's cargo bay are presently compared with ground measurements of the particulates emitted by the Shuttle's SRBs, as well as with the expected natural particulate environment as measured by Skylab. Chemical analysis is shown to reveal the difference between natural and anthropogenic space debris; the most probable primary source of the Space Shuttle's particulate environment is the SRB exhaust.

Susko, Michael↗

Wind measurements by electromagnetic probes

The operation and performance characteristics of the Marshall Space Flight Center's Radar Wind Profiler, designed to provide measurement of the wind in the troposphere, are discussed. The Radar Wind Profiler uses a technology similar to that used in conventional Doppler radar systems, except the frequency is generally lower, antenna is larger, and dwell time is much longer. Its primary function is to monitor the vertical wind profile prior to launch of the Space Shuttle at more frequency intervals and nearer to launch time than is presently possible with the conventional balloon systems. A new wind profile will be obtained on the order of every 15 min based on an average of five wind profiles measured every 3 min at a height interval of 150 m to 20 km. The most significant features of the Radar Wind Profiler are the continuity in time and reliability.

Susko, Michael↗

Wind measurements by electromagnetic probes

The emerging technology of electromagnetic probing of the atmosphere to measure winds used in a space vehicle ascent winds load calculations is presented. The frequency range, altitude, and resolution for the following probes are presented: lidars, microwave radars, and clear-air Doppler radars (popularly known as wind profilers). The electromagnetic probing of the atmosphere by clear-air radars and lasers is the new technology to supplement balloon-borne wind sensors used to determine ascent wind loads of space vehicles. The electromagnetic probes measure the wind velocity using the Doppler effect. This is the radar technology used in MSFC's Radar Wind Profiler, and is similar to the technology used in conventional Doppler systems except that the frequency is generally lower, antenna is bigger, and dwell time much longer. Designed for unattended and automated instrumentation in providing measurements of the wind in the troposphere, the profiler employs Doppler radar technology and is currently being put in operation at NASA Kennedy Space Center, Florida.

Susko, Michael↗

Analysis of the Bivariate Parameter Wind Differences Between Jimsphere and Windsonde

An analysis is presented for the bivariate parameter differences between the FPS-16 Radar/Jimsphere and the Meteorological Sounding System (MSS) Windsonde. The Jimsphere is used as the standard to measure the ascent wind during the Space Shuttle launches at Kennedy Space Center, Florida, and the Windsonde is the backup system. In addition, a discussion of the terrestrial environment (below 20 km) and a description of the Jimsphere and Windsonde wind sensors are given. Computation of the wind statistics from 64 paired Jimsphere and Windsonde balloon releases in support of 14 Space Shuttle launches shows a good agreement between the two wind sensors. From the analysis of buildup and back-off data for various scales of distance and the comparison of the cumulative percent frequency (CPF) versus wind speed change, it is shown that the wind speed change for various scales of distances for the Jimsphere and Windsonde compare favorably.

Susko, Michael↗