Despite hopes for a launch before the end of the year, NASA has decided to hold the STS121 mission, originally scheduled to launch in September, until March of next year. This gives NASA engineers a full seven months to redesign the PAL ramp foam to eliminate a repeat of the foam shedding incident that marred the STS114 “Return To Flight” launch last month.
Plans are also being formulated for a May 2006 launch for STS-115 using Atlantis. Planning for missions STS-116, STS-117, and STS-118 is more or less on hold with staff told to “do no negative work.”
In a news conference today, NASA administrators laid out the details of the work to be done between now and March, with “minimizing” foam shedding now the admitted goal. Engineers have come to grips with the fact that is impossible to eliminate the tank foam problem that has plagued the Space Shuttle from its very first launch. NASA officials have admitted that they were “very lucky” that other shuttles did not experience the level of damage that caused Shuttle Columbia to break up during reentry, killing all aboard.
NASA Administrator Michael Griffin and Associate Administrator for Space Operations Bill Gerstenmaier made the announcement today at a news conference at the agency’s headquarters in Washington.
“We are giving ourselves what we hope is plenty of time to evaluate where we are,” said Administrator Griffin. “We don’t see the tasks remaining before us being as difficult as the path behind us.”
Based on NASA’s self-imposed optimum lighting requirements, the earliest possible launch opportunity for the STS-121 mission is March 4, 2006. The Space Shuttle Discovery will be used for the mission, instead of Space Shuttle Atlantis.
Moving toward a no earlier than March launch for STS-121 will allow engineering teams more time to properly evaluate the issue of large pieces of insulating foam that came off Discovery’s external fuel tank during launch last month. Targeting March also allows the Space Shuttle Program to put itself into a better posture for future Shuttle missions to the Space Station. Changing Orbiters for the STS-121 mission enables use of Atlantis for the following mission, STS-115, which will resume assembly of the Station.
The switch frees Atlantis to fly the remaining Space Station truss segments, which are too heavy for Discovery, in 2006. By changing the Orbiter line up, the Shuttle program will not have to do two back-to-back missions with Atlantis, as previously scheduled.
“It really makes sense to move to the March timeframe,” Gerstenmaier said. “We’re looking at the Shuttle missions to support the most robust flight sequence for the Space Station and to make the whole sequence flow better. This extra time helps us make sure that all the work we need to do fits and that there are no other issues.”
Discovery’s recent mission, STS-114, and the STS-121 mission are test flights. They will enable NASA to evaluate new safety procedures and equipment, giving the agency greater confidence that the Shuttle can be flown safely through its planned retirement date of 2010.
The external fuel tanks at NASA’s Kennedy Space Center in Florida will be shipped back to the Michoud Assembly Facility in Louisiana for tests and potential modifications.
NASA has a lot of work to do between now and March, when its next launch is likely to have a repeat of the media focus that followed the STS-114 launch and mission.
(Ho hum… 7 more months…)