Inspectors found a 5-inch-long crack in the foam insulation covering the 
shuttle Discovery's external fuel tank, and NASA managers were deciding Monday 
whether to call off the scheduled Fourth of July launch. 
 
 
   The Space Shuttle Discovery is pictured on Pad 
 39B at the Kennedy Space Center in Cape Canaveral, Fla., on Sunday, July 
 2, 2006. NASA officials scrubbed the planned launch of mission STS-121 
 Sunday because of weather. The mission, which was also scrubbed on 
 Saturday, is now scheduled for Tuesday, July 4, 
 2006. [AP] | 
The crack was spotted during an overnight inspection. NASA had scrubbed 
launch plans Saturday and Sunday because of poor weather and had removed fuel 
from the tank.
The inspectors found the crack, which was an eighth of an inch deep, in the 
foam on a bracket near the top of the external fuel tank. 
"We don't know if it's a problem or not," NASA spokesman George Diller said 
Monday. 
Officials were meeting to determine whether it could be fixed for a Tuesday 
liftoff. 
If NASA decides to go ahead with the launch Tuesday, it would be the first 
manned launch by the United States on the nation's birthday, and only the second 
liftoff of a space shuttle since the 2003 Columbia disaster. 
Concerns about cracks in the fuel tank's foam insulation have dogged the 
program since Columbia exploded over Texas on Feb. 1, 2003. A chunk of flyaway 
foam had damaged Columbia's wing during liftoff, allowing superheated gas to 
penetrate the shuttle when it re-entered the atmosphere. 
NASA tried to fix the problem before trying another launch, but more foam 
broke off Discovery's redesigned tank last July, barely missing the shuttle. 
NASA Administrator Michael Griffin decided the shuttle should go into orbit 
despite the concerns of two top agency managers who wanted additional repairs to 
the foam insulation. 
The mission for Discovery's crew this time is to test shuttle-inspection 
techniques, deliver supplies to the international space station and drop off 
German astronaut Thomas Reiter for a six-month stay. 
The weather forecast for a Tuesday liftoff was better than it was on Sunday 
or Monday, with a 40 percent chance that storms at launch time would prevent 
liftoff, said U.S. Air Force 1st Lt. Kaleb Nordgren, a shuttle weather 
forecaster. NASA planned to make launch attempts on Tuesday and on Wednesday if 
necessary.