KENNEDY SPACE CENTER, Fla. — NASA officials Friday scheduled
space shuttle Endeavour to lift off Thursday morning after
deciding that repairs conducted on the launch pad fixed
potential O-ring problems. Over the past week, technicians,
wearing special suits to prevent static electricity that could
ignite the rockets, were placed in the bell-shaped nozzles of
Endeavour's two solid rocket boosters. The workers replaced
putty that insulates nozzle joints, using a small pump as a
vacuum to prevent air pockets. During the past two shuttle
launches, NASA has discovered, air pockets allowed hot rocket
gas to penetrate the putty and singe the O-rings in a particular
nozzle joint. The problem caused almost a month's delay in
Endeavour's science mission originally scheduled for early
August. Shuttle manager Tommy Holloway said he is satisfied with
the repairs though there are no tests to verify the launch-pad
work. Identical repairs were performed successfully on spare
nozzles by booster manufacturer Thiokol Corp. in U