Space: Those Last Few Seconds

Death comes quickly in space, unless it comes very slowly. The crew of the shuttle Challenger is thought--or hoped--to have suffered little. Crew members of Apollo 13, had they not made it home, would have needed days to breathe up all their air and suffocate. Ever since the crack-up of the shuttle Columbia last month, NASA has wanted to know how the astronauts on that doomed ship met their end--believing that the precise sequence of events on the crew decks would reveal a lot about the precise sequence of breakdowns throughout the ship.

Slowly, investigators are piecing together the answers. Space-agency technicians have been scrutinizing the final, fragmentary transmissions that came from the disintegrating Columbia, particularly a telltale, 2-sec. scrap of data deciphered for the first time only last week. Analysts are also paying closer attention to the 13-min. videotape, recovered partly intact from the wreckage, that the crew made during re-entry. Perhaps most important, some former astronauts have been willing to speculate--cautiously--on what might have been taking place inside Columbia in the critical minutes after the video went black and before the ship was destroyed. The sketchy picture that all this paints is of a professional team of astronauts doing everything they could to fly their vehicle, even as events overtook them.

The videotape, which runs from 8:35 to 8:48 a.m. E.T.--ending about 11 min. before the ship was destroyed--shows the astronauts just where they ought to have been that late in the mission, with commander Rick Husband, pilot William McCool and crew members Laurel Clark and Kalpana Chawla strapped into their seats on the main flight deck. Crewmates Ilan Ramon, David Brown and Michael Anderson were out of view, similarly belted into place on the middeck below. When the tape begins, Chawla and Clark are finishing their suiting up, while Husband and McCool are busy flying the ship.

"Oh, shoot!" Husband says, as he accidentally hits a control that briefly switches the spacecraft from autopilot to manual. "We bumped the stick earlier."

"Not a problem, Rick," Mission Control answers. "Yeah, but ..." Husband grumbles, sounding displeased that the harmless mistake happened at all.

Outside the windows, glowing plasma is flickering like lightning. "Is that [maneuvering] jets firing in the back?" Chawla asks. McCool replies, "That might be some plasma. The jets are not firing now."

The crew members spend the next few minutes enjoying the light show while tending to their suits and instruments and feeling for the return of the first ghost of gravity. When the ship is pulling only one-hundredth of a G, McCool is heard commenting that when he drops a card, it falls, a sure sign that Columbia is crossing the line from extraterrestrial to terrestrial.

Shortly afterward, the video record ends, but things probably remained routine until 3 min. later--8 min. before the accident--when NASA got its first indication of what it dryly calls off-nominal aero increments. Translation: the shuttle was growing unstable because of the loss of insulating tiles, and the computer-controlled flaps were attempting to compensate. Inside the ship this would not have caused concern.