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STS-133 Rollback to VAB 22nd Dec 2010
Earlier this week, the Shuttle Discovery was returned to the VAB to enable technicians to resume their X-Ray examination of the -Z, or back side of the tank that was not able to be examined while the Orbiter was on the launch pad. The trip back to the VAB was interrupted several times by over heating bearings. By 6:20 AM the crawler had entered the VAB, and by 7:02 AM the launch platform was lowered onto it’s pedestals in the VAB and the rollback was complete after a travel time of 8 hours and 13 minutes. This was the 18th time that an Orbiter had completed a return trip to the VAB in the history of the Shuttle program.
Early analysis of the huge amount of data generated by a tanking test performed on December 17th showed no strains or temperatures outside of expected parameters. The tanking test was performed in an attempt to gather more data on which to base decisions after earlier computer analysis and metallurgical tests showed no root cause for the cracking that halted the November 3rd launch attempt to the ISS. For the tanking test, technicians had instrumented the foam covered tank placing 39 strain gauges and 50 thermal sensors in two areas, one where the damaged stringers were repaired and another location part way around the tank at an undamaged section.
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