Few Air Force pilots would dare fly into combat without an ejection seat. Could ejection seats or escape pods have saved the Columbiaastronauts?
Probably not. The Columbia disaster occurred within a matter of seconds, even milliseconds, which is hardly enough time for a seven-person crew to load into escape capsules. As for ejection seats, few pilots have ever survived popping out of a plane traveling in excess of 630 mph. When it broke apart, Columbia was hurtling along at Mach 18—18 times the speed of sound—so ejection would have brought certain death. In addition, the Columbia disintegrated at an altitude of 200,000 feet; 100,000 feet is generally considered to be the ceiling for a midair ejection to be survivable.
NASA has, from time to time, added escape devices to its shuttle fleet. For its first four flights, in 1981 and 1982, the Columbia featured ejection seats for the two-man crew. But these were removed as the shuttle crews expanded to five to seven members, and NASA deemed the shuttle safe enough to do without.
That aura of safety evaporated in the wake of the Challenger disaster in 1986, and NASA did add escape systems to the remaining shuttles. In the event of a disastrous takeoff, a side hatch can be jettisoned. A telescoping pole is then supposed to be extended beyond the wing, allowing the crew to attach their parachute rings and slide out into the clear. This escape plan can work only under limited circumstances, however. The shuttle cannot be much higher than 20,000 feet for the apparatus to work, and it must be in a controlled glide, not a steep ascent. Even then, the evacuation procedure could take upward of two minutes.
NASA revisited the prospect of adding escape pods or revamped ejection seats to the shuttle in 2001, when the agency's Safety Advisory Panel put together a report on the options. It concluded that "none of the options for crew escape can be funded within the current constraints on the space shuttle budget." The panel estimated that retrofitting the fleet with escape pods, which could survive drops of less than 200,000 feet, may have required 18 months and nearly $1 billion. And there's a design problem: Escape pods require life-support mechanisms, and engineers would have to design a pod light enough to fit in the cargo bay.
NASA has considered adding escape systems to its Orbital Space Plane, a next-generation vehicle slated to begin ferrying astronauts to and from the International Space Station around 2010. Last November, NASA awarded Lockheed Martin a $53 million contract to research escape options that might enable crews to abandon ship after a bungled takeoff—say, one in which critical heat-resistant tiles are damaged.
(Did witnesses really hear the Columbia split apart? Click here to find out.)