Glitch forces delay
in high-profile shuttle launch
Heater failure spoils Endeavour countdown; liftoff postponed at least three days
One of the highest-profile space shuttle launches in NASA history was delayed on Friday, due to a problem with the heaters in one of Endeavour's auxiliary power units.
The countdown was called off even as the shuttle's six-man crew was heading for Launch Pad 39A. Liftoff would be delayed for at least three days, and most likely longer, while launch-pad workers looked into the problem, NASA launch director Mike Leinbach said.
The shuttle's three auxiliary power units provide hydraulic pressure to operate the control system during atmospheric flight. Although the shuttle can operate with only one of the units working, NASA's launch rules state that all three have to be functional for liftoff.