Endeavour, the newest addition to the four-orbiter fleet, is named after the first ship commanded by James Cook, the 18th century British explorer, navigator and astronomer. For the first time, a ... national competition involving students in elementary and secondary schools produced the name of the new orbiter; it was announced by President George Bush in 1989. The Space Shuttle orbiter Endeavour was delivered to Kennedy Space Center in May 1991, and flew its first mission, highlighted by the dramatic rescue of a stranded communications satellite, a year later in May 1992.
Endeavour features new hardware designed to improve and expand orbiter capabilities. Most of this equipment was later incorporated into the other three orbiters during out-of-service major inspection and modification programs. Endeavour's upgrades include:
-A 40-foot diameter drag chute that is expected to reduce the orbiter's rollout distance by 1,000 to 2,000 feet.
-The plumbing and electrical connections needed for Extended Duration Orbiter (EDO) modifications to allow up to 28-day missions.
-Updated avionics systems that include advanced general purpose computers, improved inertial measurement units and tactical air navigation systems, enhanced master events controllers and multiplexer-demultiplexers, a solid-state star tracker and improved nose wheel steering mechanisms.
-An improved version of the Auxiliary Power Units (APU's) that provide power to operate the Shuttle's hydraulic systems.
[Summary provided by NASA]