No amount of effort could have saved the damaged space shuttle Columbia from breaking up as it re-entered the atmosphere, according to an internal NASA report that will be presented to the board investigating the accident.
According to the new analysis, the best option for returning the shuttle safely would have been to throw every nonessential object overboard, reducing the craft's weight by more than 15 tons. The effort would have required two or more spacewalks by the seven astronauts to unload the science experiments, the SpaceHab research module, equipment, water and more.
The lighter craft would have been able to enter the atmosphere without having to dissipate so much of the heat that doomed Columbia on Feb. 1.
However, according to the NASA analysis, making the shuttle lighter would have reduced the maximum heating by only 7 percent in the area along the left wing's leading edge, where investigators now believe superheated gases entered the wing, destroying the spacecraft.
The team that performed the analysis was led by Leroy E. Cain, the NASA flight director on duty the morning Columbia broke apart. The purpose of the review was to determine what, if anything, might have been done to reduce heat and stress on the damaged craft during re-entry.
The findings of Cain's group will be presented next week to the independent board headed by retired Adm. Harold W. Gehman Jr. that is investigating the disaster.
The new analysis appears to bring NASA closer to acknowledging that damage to the shuttle's left wing, which was evaluated by NASA engineers during the flight and dismissed as not threatening to the spacecraft, was in fact the fatal blow.
Another NASA report pointed to the 2-pound piece of foam insulation that struck the shuttle's wing about 80 seconds after liftoff as a likely cause of the breach in the wing that led to the shuttle's destruction.
The question of whether measures could have been taken to repair damage to the shuttle, or find other means of protecting the crew, was discussed urgently during the mission and has become a point of controversy in the ensuing months.