The Spaceflight Meteorology Group

Postflight Mission Summary for STS-83

April 21, 1997

Columbia Flight Launches Late and Lands Early at KSC...

After a one day delay due to the requirement to insulate water coolant lines, Space Shuttle Columbia lifted off on April 4, 1997 at 1920 UTC. The afternoon launch was free of any weather concerns as high pressure centered over the Atlantic just off the Florida coast afforded fair weather and light surface winds at the Kennedy Space Center (KSC).

Columbia, however, was forced to cut short its mission and return early. One of Columbia’s three fuel cells which furnish electricity to the orbitor was not working properly. It was decided on April 6 to declare a minimum duration flight (MDF) and bring Columbia back early on April 8, 1997.

Surface winds were the main forecast problem on landing day. Northeast surface winds very near the 15kt crosswind limit were forecast to develop at the KSC Shuttle Landing Facility (SLF) for the afternoon landing. At Edwards AFB (EDW), the other possible landing site, surface winds were forecast to increase during the afternoon as an upper low deepened over the southern rockies. Forecast winds peaking to 30kts would violate a number of weather flight rules at EDW. In the morning, KSC winds at times exceeded the crosswind limit. However, about 2 1/2 hours before landing time, winds backed to a more northerly direction, yielding a smaller crosswind on the NW-SE oriented runway. After noting this trend, SMG predicted the SLF winds would stay just below the crosswind exceedance limits and a “GO” forecast for KSC was issued two hours before touchdown. Columbia landed at KSC April 8, 1997 at 1834Z. SLF crosswinds were below limits at landing time.

NASA is currently discussing plans to relaunch the STS-83 mission in early July of 1997. This would allow completion of many of the STS-83 Microgravity Science Laboratory experiments.

The lead forecaster for STS-83 was Richard Lafosse. Assistant lead/TAL site forecaster was Wayne Baggett. The lead Techniques Development Unit meteorologist was Tim Oram.

Submitted by:

Richard Lafosse STS-83 Lead Forecaster