Erratic Pressure Tank Reading Could Bring Shuttle Down Early

CAPE CANAVERAL, Fla. — A puzzling pressure reading on a hydrogen tank forced Discovery’s astronauts to dim lights and turn off computers to conserve power today and raised the possibility of an early return to Earth.

Mission Control emphasized the trouble posed no threat to the five-member crew or its mission.

Flight Director Ron Dittmore said the hydrogen tank exhibited erratic readings.

The tank is one of three that feeds liquid hydrogen to Discovery’s fuel cells. Without it, the shuttle might not have electrical energy to support a five-day flight.

Flight Director Al Pennington said he was optimistic the problem would be solved. “Right now we plan to land on Saturday, unless we get some engineering data that says we can’t use that tank,” he said.

Pennington said a decision would have to be made by early Thursday.