Discovery Launch Delayed Indefinitely

Space shuttle managers feel that more analysis is needed before they can clear space shuttle Discovery for its final launch. The launch was scrubbed twice in November and slipped to no earlier than December 3. Shuttle program manager John Shannon said at a press conference today that it will not be ready for the December 3-7 window at all. The next window, December 17-20, is an option, but he is not sure they will be ready by then either. If not, the launch will have to wait untl February.

Two cracks were found in “stringers” on Discovery’s external tank after the tank was filled and emptied several times during the previous launch attempts. NASA needs time to do additional analysis to ensure that cracks do not develop during ascent and cause foam to be shed. Damage to the space shuttle Columbia orbiter from external tank foam shedding caused Columbia to disintegrate during reentry in 2003, killing all seven aboard.

Shannon said repeatedly today that NASA needs to understand its risk exposure better before commiting to launch. The shuttle is still on the launch pad and engineers have access to only one side of the tank. Rolling it back to the Vehicle Assembly Building so they can study the opposite side is one option they are considering, but no decisions have been finalized.