CAPE CANAVERAL, Fla. - Hoping to finally fly Wednesday night, NASA scrambled to remove a metal pin that ended up on space shuttle Discovery and led to an embarrassing launch delay.
The 4-inch pin was spotted with binoculars during a routine inspection of the shuttle Tuesday, a few hours before liftoff. It was wedged next to the liquid-oxygen line between Discovery and its external fuel tank.
Rather than risk damage to Discovery, NASA called off the launch - the 100th flight of the space shuttle program.
''I don't want to sugarcoat anything,'' shuttle program manager Ron Dittemore said. ''It was a mistake. There's a mistake involved here.''
Engineers feared the pin could fall onto the launch pad 35 feet below and ricochet up toward the shuttle or get sucked against one of the main engines at ignition. Either way, the results could have been ''severe,'' Dittemore said.
NASA said worker error likely was to blame.
Shuttle manager Dave King said another launch attempt would be made Wednesday - provided the pin can be removed, the area can be inspected for damage and all other preparations can be completed in time.
''It's a tight schedule,'' King said. ''There's not a lot of play in there, but we think we can make it.''
It will be the fourth launch attempt in almost a week for the space station construction mission. The previous delays were caused by gusty wind and mechanical problems.
Unlike earlier attempts, Discovery's seven astronauts were on board the shuttle when the countdown was halted Tuesday. A few of them looked glum as they crawled out.
''We just can't get comfortable with the pin,'' launch director Mike Leinbach informed them.
The pin, believed to be part of a work platform or handrail, has a 3-inch T handle and is attached to a 12-inch wire cord. To NASA's dismay, inspections conducted late Monday and early Tuesday did not catch it.
As the minutes ticked away, launch managers considered sending out a team to try to remove the pin with streams of water or compressed air. But they decided it was safer and more prudent to halt the countdown and roll the launch tower back around Discovery to gain access to the area.
Dittemore promised to get to the bottom of the problem. The pin, like all other tools and equipment used at the pad, should have been listed on an inventory.
''We have some work to do to figure out what went wrong and what we're going to do about it,'' he said.
Discovery is loaded with two new segments for the international space station: a boxy framework that contains motion-control gyroscopes and antennas, and a shuttle docking port to be used for future linkups.
Until these pieces are installed on the space station, the first residents cannot be launched. The first permanent crew is scheduled to rocket away from Kazakstan on Oct. 30.
---
On the Net:
NASA: http://spaceflight.nasa.gov/index-m.html
