Three Terrifying Minutes?

By MICHAEL D. LEMONICK

Just three seconds after Commander Francis Scobee radioed "Roger, go at throttle up" last Jan. 28, the Challenger was smashed to pieces, instantly killing the shuttle astronauts. That, at least, is what most Americans have believed for the past six months. Last week NASA revealed the chilling truth: at best, the crew of the doomed shuttle knew, if only for a few seconds, that something was terribly wrong. At worst, they remained conscious for two minutes and 45 seconds, until the crew compartment, still largely intact, smashed into the Atlantic.

As recently as mid-July, a NASA spokesman had announced that examination of a tape recovered from the wreckage (and restored by IBM engineers after its long immersion in seawater) indicated that the crew members were "unaware of the events associated with the tragedy." But the agency admitted last week that a more detailed analysis had uncovered a voice recorded three seconds after Scobee's final words, just before all data were cut off. The voice was that of Pilot Michael Smith. His exclamation: "Uh-oh!"

The NASA announcement indicates that at least some of the crew were functioning for several seconds after the explosion and possibly longer. Evidence that they had survived the blast came from four emergency air packs, connected to the astronauts' helmets during launch, that were pulled months ago from the ocean. Three of the packs, designed to supply air if the astronauts had to exit the shuttle on the launch pad through noxious fumes, had been manually activated. One was identified as Smith's. Since the Challenger pilot, locked into his safety harness, could not have reached the control, it must have been turned on by either Ellison Onizuka or Judith Resnik, who sat behind him on the spacecraft's top deck.

Dr. Joseph Kerwin, director of Space and Life Sciences at the Johnson Space Center, wrote in last week's report, "The forces on the orbiter at breakup were probably too low to cause death or serious injury . . . the crew possibly, but not certainly, lost consciousness in the seconds following orbiter breakup." The maximum acceleration forces felt by the astronauts as their cabin was blown away from the explosion--estimated at 12 to 20 Gs, or 12 to 20 times the force of gravity--were "quite brief," Kerwin added, and "survivable." Even if the sealed crew compartment had ruptured and depressurized, he said at a news conference last week, the crew could have remained conscious for six to 15 seconds. If the cabin remained intact, though, they may have been conscious for nearly three terrifying minutes--as upward momentum carried the cabin from 48,000 ft. at the moment of the fireball to 65,000 ft. 25 seconds later, before it fell, tumbling and spinning, and crashed into the waves at 207 m.p.h. with a force of about 200 Gs. Said a National Transportation Safety Board expert: "Water is like concrete when you hit it at 200 m.p.h."

One member of the Rogers commission has expressed anger at the belated revelations about the Challenger crew. "NASA is finally in the process of coming clean," he commented. "They even tried to stonewall us (the commission) on the tapes, telling us that they never release tapes. You are going to learn eventually that some of the crew lived longer than others, and that's how it was."

With reporting by Jerry Hannifin/Washington