NASA scraps planned space shuttle launch

Associated Press

CAPE CANAVERAL, Fla. – NASA called off tonight’s launch of space shuttle Discovery because of last-minute concerns over bolts on the external fuel tank.

The launch – the 100th of the space shuttle program – was bumped to Friday night at the earliest.

While analyzing film of Atlantis’ Sept. 8 launch on Wednesday, engineers noticed that one of the three bolts between Atlantis and the external fuel tank did not retract properly eight minutes into the flight. Photographs showed about 2 inches of the 14-inch bolt sticking out on the tank.

Engineers reviewed the film again today but could not determine what happened. As a result, the countdown was halted, just as fueling was to begin. The astronauts had not yet boarded the shuttle.

NASA wants to make sure the problem does not occur on Discovery. Engineers also are scrambling to determine the impact of such a problem. At worst, a protruding bolt could cause the separated fuel tank to tumble and possibly cause the tank to slam into the shuttle.

Space shuttles are launched with two solid-fuel boosters, which are jettisoned two minutes after takeoff, plus the larger, rust-colored fuel tank, which is discarded into the ocean after the shuttle reaches orbit.

The film depicting the problem with the tank’s bolt did not become available until Atlantis returned to Earth on Sept. 20. The troublesome bolt can’t be studied directly; it’s at the bottom of the ocean.

“We think it’s prudent to stand down for a day to give our engineers time to review the data, to review the rationale for flight and to move slowly and with all due concern for this issue,” said shuttle manager James Halsell. “In other words, we do not want to get ‘go fever.’ “

Discovery is loaded with two new pieces for the international space station, a girderlike truss and a docking port for future shuttle visits.

The 18,000-pound truss contains antennas and motion-control gyroscopes. The seven-member shuttle crew will use the shuttle robot arm to attach the truss and docking port to the space station. The astronauts will go out on four back-to-back spacewalks to wire up the pieces.

Astronauts have not hooked up major pieces to the space station since the initial components were launched in 1998. The last three shuttle visits were essentially supply runs.

Once Discovery’s 11-day mission is completed, the space station’s first permanent crew will be able to move in.

NASA astronaut Bill Shepherd and two Russian cosmonauts are scheduled to lift off from Kazakstan on Oct. 30. They will spend four months aboard the space station before returning to Earth via the space shuttle. A new three-person crew will take their place.

Shepherd and his crewmates are in Russia preparing for their flight.