Space shuttle Atlantis "could have been used to rescue the crew"
Had the damage to the Columbia space shuttle been spotted before re-entry into the Earth's atmosphere, a rescue attempt to save the crew could have been made, according to the final report on the orbiter's fatal break-up.
As part of its inquiry into the disaster, the Columbia Accident Investigation Board (CAIB) asked the Nasa space agency to explore what could have been done to repair or evacuate the ship.
Given the nature of the damage to the vehicle, with the heat shield compromised, Nasa deemed that a repair would have been too high risk.
However, experts from the space agency told the board that if the mission controllers had known by at least the seventh day of the mission that a rescue was possible, the space shuttle Atlantis could have been scrambled to carry out an evacuation.
Columbia, which broke up on 1 February, 2003, killing all seven astronauts on board, could have remained in orbit until 15 February, according Nasa.
Atlantis, which was due to be launched in March, could have been ready for a lift-off between 10-15 February, the report states, and weather records for that period show that the conditions for the attempt were satisfactory.
"Accelerated processing of Atlantis might have provided a window in which Atlantis could rendezvous with Columbia before Columbia's limited consumables ran out," the report said.
Spacewalk to safety
Under the proposed plan, Atlantis would have been sent up with a crew of just four astronauts - a commander, a pilot and two people trained in carrying out space walks.
On Atlantis' first day in orbit, it would have been able to rendezvous with the stricken Columbia - with the two shuttles positioned facing each other, each with their payload doors open.
The Columbia crew would then have transferred to the other shuttle in a series of spacewalks.
Once securely on board, the two crews could have returned to Earth in Atlantis, with four astronauts positioned on the shuttle's flight deck and seven in the mid-deck.
As for Columbia itself, it could have either been brought down out of orbit, to land somewhere in the Pacific Ocean, or placed in a higher orbit and left until a repair mission could be sent up at a later date.
"The rescue was considered challenging, but feasible," the CAIB report said.
However, as the highly critical report says, Nasa staff failed to notice of the damage to Columbia's left wing, which was caused by falling foam debris during its 16 January lift-off.