Temperatures inside the shuttle's left wing shot up within 16 seconds of the ship reaching the maximum temperatures it would encounter during atmosphere re-entry, readings from Columbia's flight recorder show.
Two sensors behind panels in the leading edge of the wing relayed high-temperature readings one minute and eight seconds before the first abnormal sensor data was radioed to ground-based computers, Laura Brown, spokeswoman with the Columbia Accident Investigation Board, said Sunday.
She said that the recorder, which was found on a hill in Texas, contains "significant" data on shuttle temperatures, pressures and aerodynamic indicators during re-entry. The recorder doesn't relay data during flight.
So far, information from 420 sensors has been extracted from the tape, with more than 200 additional sensor readings awaiting analysis. The work is being done at the Johnson Space Center in Houston.
Columbia disintegrated over east Texas on Feb. 1 as it headed toward a landing strip in Florida to conclude a 16-day research mission. Investigators haven't yet determined the exact cause of the accident, but they have evidence that a breach in the left wing allowed superheated air to get inside the structure, dooming the ship and its crew.
Attention has focused on possible damage to the wing's leading edge from a piece of insulating foam that fell off the shuttle's fuel tank and struck the ship during its launch Jan. 16.
The board also is studying radar data showing an object coming off the orbiter during its second day in space.