One major change is an escape system designed for use if the shuttle has to ditch in the ocean.

A video simulation of this escape system's operation was released in January 2011.

If 1NT is doubled, some sort of escape system may be used.

The accident happened when she tried to demonstrate the use of the escape system designed to lower an occupant to the ground from a window.

I hear they'll have the new escape system in place for the first flight.

Mr. Scoppetta said the escape system was a more critical need.

Engineers said the new escape system could not be used while the shuttle was connnected to the rockets.

A rudimentary escape system, not present on the Challenger, is being installed.

"A final decision to implement a space shuttle crew escape system has not been made," the report said.

The escape system successfully pulled the spacecraft to safety.