CAPE CANAVERAL, Fla. - Launching shuttle Atlantis on a risky mission to rescue Columbia's astronauts was theoretically feasible but unrealistic, based on assumptions and findings in a NASA study done for the Columbia Accident Investigation Board.
The study outlines a scenario that would have rushed Atlantis to the launch pad, staged a rendezvous with Columbia in orbit and spacewalked the seven astronauts to safety. A second scenario looked at having the crew make repairs to Columbia's damaged left wing in orbit without sending a rescue flight.
The rescue mission, however, depends on two assumptions. The first is that mission managers would have had definitive proof of catastrophic damage to Columbia within four days of its Jan. 16 liftoff.
The second is that managers at the National Aeronautics and Space Administration would have proceeded to launch Atlantis, ignoring crucial tests and flight rules while knowing that an unexplained failure during Columbia's launch had crippled that orbiter.
"We set a scenario here that was not the scenario of Columbia," said retired Adm. Harold W. Gehman Jr., chairman of the investigation board.
Reaction to those assumptions by several NASA managers and astronauts contacted by the Orlando Sentinel ranged from "unrealistic" to "laughable."
"It's nice to say we would have done something," former shuttle commander Rick Searfoss said, "but you get killed in this business when you wing things like that."
The board asked for the study to see if it was conceivable that anything could have been done to save Columbia's crew after a piece of foam insulation broke free from the ship's external fuel tank during launch and struck the leading edge of the left wing. The impact is suspected of piercing Columbia's thermal-protection system, causing the shuttle to break up over central Texas while returning to Earth on Feb. 1.
According to NASA sources familiar with the study, the hypothetical rescue unfolds like this:
After learning of damage from the foam strike, mission managers dispatch astronauts on a Jan. 20 spacewalk to inspect the problem, then shut down Columbia's nonessential systems to conserve power.
Doctors estimate the crew could have stayed alive up to Feb. 15, although carbon dioxide levels would have reached almost double the normal limits.
Around-the-clock processing possibly could have prepared Atlantis for a night launch Feb. 10 or Feb. 11 if all went perfectly. Atlantis could have reached Columbia on or about Feb. 12.
Once in orbit, Atlantis would have made a rendezvous with Columbia and hover above with the shuttles' open cargo bays facing each other 50 to 90 feet apart.
A spacewalker attached to a safety tether would carry over spacesuits from Atlantis and retrieve Columbia's crew in pairs. A total of 11 astronauts would ride home on Atlantis, seven strapped into seats and four sitting on the floor of the shuttle's middeck. Columbia would be abandoned and jettisoned into the Pacific Ocean by remote control.
"It isn't easy," Gehman said of the plan. "It's not even highly likely, but it is conceivable."
Another option would have had spacewalkers patch the damaged part of the leading edge, by jamming heat-resistant materials in the breach, then fashioning a covering.
Gehman said no analysis had been done on whether such a patch could have held up during re-entry.
Michael Cabbage writes for The Orlando Sentinel, a Tribune Publishing newspaper.