Shuttle program managers are now aiming for a planning window of May 2006 for the launch of the next space shuttle mission, STS-121.
Image above: External Tank 120 leaves Kennedy Space Center for work at the Michoud Assembly Facility in New Orleans
NASA is making progress addressing the problem that caused foam to come off the External Tank during Discovery's Return to Flight mission in July.
Meanwhile, the powering of the shuttle Endeavour earlier this month signaled the end of the orbiter's major modification period at NASA's Kennedy Space Center, Fla.
"Having three operational vehicles in the fleet affords the shuttle program great schedule flexibility, as we move toward flying safely and completing the international space station," said Space Shuttle Program Manager Wayne Hale.
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