Columbia Accident Investigation and Return-to-Flight Effort.

The article reports on the findings of the Columbia Accident Investigation Board (CAIB) regarding the Space Shuttle Columbia accident in the U.S. The CAIB announced that the cause of the loss of Columbia and its crew was a breach in the left wing leading edge reinforced carbon-carbon thermal protection system. The breach was initiated by the impact of thermal insulating foam that had separated from the orbiter's external fuel tank. Also, this breach allowed superheated air to penetrate behind the leading edge and erode the aluminum structure of the left wing, which led to the breakup of the orbiter.