Optimizing the Lightning Warning Radii at Spaceport Florida

Abstract Air Force Manual 91–203 (AFMAN 91–203) directs that a lightning warning be issued when lightning is occurring within a 5 nautical mile (n mi; 1 n mi = 1.852 km) radius of a predetermined location. The 45th Weather Squadron (45 WS), located on the central eastern coast of Florida, provides weather support to Cape Canaveral Air Force Station, NASA Kennedy Space Center, and Patrick Air Force Base. The primary objective of this study is to optimize the lightning warning safety buffer; in particular, to determine if the 5 n mi safety radius can be reduced while maintaining a desired level of safety. The research uses processed Lightning Detection and Ranging II (LDAR-II) data from 2013 to 2016 to map the movement of preexisting lightning storms using ellipses. These ellipses are updated with every lightning flash. The distance from the ellipse boundary of each flash occurring outside the ellipse is recorded. Those exterior flash distances are then used to find the best-fit distribution from which the stand-off distance for the desired level of safety can be calculated. The distances from the edge of the ellipse are fit to a Weibull distribution and a reduction in the radius by 1 to 4 or 5 n mi is selected as the optimized balance between safety and operational impact. The 4 or 5 n mi radii are tested with a resulting failure rate of 3.58%, with an average savings of 130.75 false alarms and 15.7 8-h man days a year for the months of May–September.

Download Full-text

Investigation of a washer embedded in an orbiter vehicle tile

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100171006 ◽

1994 ◽

Vol 52 ◽

pp. 654-655

Author(s):

H. S. Kim ◽

V. J. Cummings

Keyword(s):

Phase Analysis ◽

Air Force ◽

Thermal Protection ◽

Space Shuttle ◽

Lower Surface ◽

Thermal Protection System ◽

Protection System ◽

Kennedy Space Center ◽

Air Force Base ◽

Kennedy Space

At NASA’s Kennedy Space Center (KSC), an engineering debris team performs a post-landing inspection of the space shuttle orbiter for debris and for anomalies in the thermal protection system. The areas of inspection and debris sampling include the orbiter windows, lower surface orbiter tiles, reinforced carbon-carbon panels of the orbiter wings, and the external tank (ET)/orbiter umbilicals.On October 18, 1989, the space shuttle Atlantis was launched from launch pad 39B at KSC. Atlantis landed on runway 23 at Edwards Air Force Base, California on October 23, 1989. During the post-landing inspection performed October 23-24, 1989, a washer, approximately 1/2 inch in diameter, was found embedded in one of the lower surface tiles forward of the LH2 ET/orbiter umbilical area. The washer was oriented perpendicular to the airflow, and approximately half of the washer protruded into the aerodynamic flow.The washer was submitted to the NASA KSC microchemistry laboratory for examination and elemental and phase analysis.

Download Full-text

Automated Lightning Flash Detection in Nighttime Visible Satellite Data

Weather and Forecasting ◽

10.1175/waf-d-10-05002.1 ◽

2011 ◽

Vol 26 (3) ◽

pp. 399-408 ◽

Cited By ~ 14

Author(s):

Richard L. Bankert ◽

Jeremy E. Solbrig ◽

Thomas F. Lee ◽

Steven D. Miller

Keyword(s):

Satellite System ◽

Lightning Strike ◽

False Alarms ◽

Lightning Flash ◽

Infrared Imager ◽

Defense Meteorological Satellite Program ◽

Lightning Detection ◽

Mapping Array ◽

Automated Technique ◽

Spectral Channels

Abstract The Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) nighttime visible channel was designed to detect earth–atmosphere features under conditions of low illumination (e.g., near the solar terminator or via moonlight reflection). However, this sensor also detects visible light emissions from various terrestrial sources (both natural and anthropogenic), including lightning-illuminated thunderstorm tops. This research presents an automated technique for objectively identifying and enhancing the bright steaks associated with lightning flashes, even in the presence of lunar illumination, derived from OLS imagery. A line-directional filter is applied to the data in order to identify lightning strike features and an associated false color imagery product enhances this information while minimizing false alarms. Comparisons of this satellite product to U.S. National Lightning Detection Network (NLDN) data in one case as well as to a lightning mapping array (LMA) in another case demonstrate general consistency to within the expected limits of detection. This algorithm is potentially useful in either finding or confirming electrically active storms anywhere on the globe, particularly those occurring in remote areas where surface-based observations are not available. Additionally, the OLS nighttime visible sensor provides heritage data for examining the potential usefulness of the Visible-Infrared Imager-Radiometer Suite (VIIRS) Day/Night Band (DNB) on future satellites including the National Polar-orbiting Operational Environmental Satellite System (NPOESS) Preparatory Project (NPP). The VIIRS DNB will offer several improvements to the legacy OLS nighttime visible channel, including full calibration and collocation with 21 narrowband spectral channels.

Download Full-text