Spaceflight Meteorology Group Provides Vital Weather
Support For Shuttle Program
Launch of Space Shuttle Atlantis from Kennedy Space Center in Cape Canaveral, Fla. (Photo: Courtesy NASA)
(Sept. 9, 2006) - With a picture-perfect launch into mostly sunny skies over Cape Canaveral, Fla., the flight of Space Shuttle Atlantis proved to be another exception to an old rule. In this case, the fourth time was a charm. Concerns over a malfunctioning engine cutoff sensor prompted NASA officials to scrub three successive launch attempts. With all of the technological issues resolved by Saturday morning, the only thing left to stand in their way - would be the weather.
The task of determining if the weather will cooperate (or not) falls to the National Weather Service's Spaceflight Meteorology Group (SMG). Working in cooperation with the U.S. Air Force's 45th Weather Squadron, SMG's mission is to provides unique world-class weather support to the U.S. Human Spaceflight effort by providing weather forecasts and briefings to NASA personnel; pre and post spaceflight weather analyses and documentation; advising the Johnson Space Center (JSC) community of adverse weather impacting the JSC complex; serving as meteorological consultants for current and future spaceflight endeavors; and, developing tools and techniques to enhance weather support and to improve the science of meteorology.
Today, one of the group's primary roles is to examine weather and climatology for launches and landings. That was not always the case. During the 1980s and much of the 1990s, when most missions weren't docking with a space station, climatology was a "prime factor" in selecting a launch window. Experts were free to set a launch window during a summer morning if the mission's science objectives allowed, knowing that thunderstorms are less likely in Florida at that time of day.
But with the restriction imposed as a result of "in-plane" time, launch windows were reduced to five or 10 minutes per day. In-plane time refers to the point when the plane of the International Space Station's orbit is over the Kennedy Space Center (KSC) launch site. Once rendezvous missions became the norm, weather -- the actual, real-time conditions at launch and landing sites -- became vitally important.
When it comes to evaluating launch day weather, SMG Director Frank Brody says there are two sets of rules involved. One set is called the Launch Commit Criteria, monitored by weather experts, Air Force officials and launch controllers at KSC. The other set, the flight rules for an abort landing, are watched by SMG and JSC flight controllers.
Their job is to make sure conditions would be safe -- if the Shuttle had to make an emergency landing. This involves watching weather conditions not only at KSC, but also at possible landing sites in New Mexico, California, Spain and France. "Basically, you can't launch unless you can land," Brody said.
While the astronauts are busy installing a second set of solar arrays designed to double the International Space Station's power generating capacity, Brody's team will be helping to plan for their safe return to earth - on September 20. SMG meteorologists will be monitoring cloud ceiling heights, visibility, cross-wind speed and location of thunderstorms near all the potential landing sites.
(Standing: L to R) -- Lead Forecaster Dan Bellue, MIC Frank Brody, Lead Forecaster Karl Silverman, ASA Tammi Barreras, Lead Forecaster Tim Oram, Techniques Development Meteorologist Doris Hood and Lead Forecaster Richard Lafosse.
(Sitting: L to R) -- Lead Forecaster Wayne Baggett, Techniques Development Meteorologist Brian Hoeth and Lead Forecasters Steve Sokol and Tim Garner (Photo: Courtesy Johnson Space Center)