Spy Satellite Glitch Delays Space Shuttle Liftoff

NASA delayed Tuesday’s scheduled blastoff of the space shuttle Atlantis for at least five days because of last-minute trouble with a rocket needed to lift a military spy satellite thousands of miles above Earth.

The countdown was halted just before workers were to begin fueling the spaceship for a night liftoff. The shuttle’s six astronauts were asleep when the flight was called off, officials said.

The problem was traced to a navigation unit in the rocket attached to the $300-million missile-warning satellite. Workers will enter the cargo bay of Atlantis and replace the unit.

“There was no way we could tell that this was coming,” said William Lenoir, head of the National Aeronautics and Space Administration’s space flight program.

The second countdown could begin early Friday, leading to a Sunday night liftoff, if the replacement and retesting of the unit goes as planned, officials said.

Lt. Col. Ernie Jaskolski, an engineer for the Air Force Space Systems Division, said that two of 10 instruments, a gyroscope and accelerometer, in the guidance unit malfunctioned during testing Tuesday.

Although just three of five pairs of instruments are needed for flight, managers wanted all of them to be working, he said.

The two bad instruments recorded 24 errors within three hours, and “it was getting worse,” said Hal DiRamio, a system manager for Boeing Space Transportation. The $50-million satellite booster is made by the Boeing Defense and Space Group near Seattle.

Officials said they want to understand why the unit failed before launching the satellite with a repaired booster. The satellite itself appeared to be fine, they said.

The crew’s main job during the 10-day flight is release of the Defense Support Program satellite, designed to warn of enemy missile launches and nuclear explosions. After being hoisted aloft 224 miles above Earth, the satellite is to be propelled into a 22,300-mile-high orbit by the booster.