What happened to the space shuttle Columbia?

Answer 1

During the launch of Columbia, foam from the external fuel tank had hit the orbiter's underside. Unknown to anyone at the time, it had punctured a hole in one of the insulating tiles on the wing. Although it was known that foam had hit Colombia, it was deemed to not have been sufficient to cause serious damage.

As the orbiter with its crew of seven were re-entering the atmosphere, the heat generated by the re-entry caused warping of the orbiter's wing frame which affected the stability of the shuttle. Eventually all control was lost and forces pulled the orbiter apart above Texas. Commander Rick Husband and Pilot Willie McCool bravely fought to control the shuttle manually in the seconds before all were killed. Much of the orbiter was recovered in pieces on the ground and provided useful information in determining the cause.