Once back on Earth, Discovery will be decommissioned while NASA launches two final flights by the shuttles Endeavour, in April, and Atlantis, in late June. Museums are competing to display all three orbiters, but no final decisions have been made.(From the NY Times not correct info..Discovery goes to the Air and Space here in DC)
On board Discovery are five men and one woman: strapped into seats on the shuttle’s upper flight deck are the commander, Steven W. Lindsey; Col. Eric A. Boe of the Air Force, the pilot; Capt. Benjamin Alvin Drew Jr. of the Air Force; and Nicole P. Stott, the flight engineer. Traveling on the ship’s lower deck are Michael R. Barratt, a physician-astronaut, and Capt. Stephen G. Bowen of the Navy.
Captain Bowen, a former submariner who was on the most recent shuttle flight, last May, is a late addition to Discovery’s crew. A veteran of five spacewalks, he was called in to replace the mission’s original lead spacewalker, Col. Timothy L. Kopra of the Army, who was injured in a bicycle mishap last month near his home in Houston.The late crew change was a relatively minor snag compared with the testing and analysis required to resolve questions about potentially dangerous cracks that were found in Discovery’s external tank after a launching scheduled for Nov. 5 was scrubbed.
The cracks developed in vertical riblike “stringers” making up the central intertank section that separates the tank’s liquid oxygen and hydrogen sections.
After exhaustive tests and analyses, engineers determined that the fractures most likely were a result of tight tolerances, manufacturing issues and the effects of super-cooled propellants on the aluminum-lithium alloy used in most of the intertank’s 108 stringers.
As it turned out, the alloy was more brittle than usual and more susceptible to stress-relief fractures when subjected to the liquid oxygen at minus 297 degrees Fahrenheit.
Engineers repaired the cracks and installed structural stiffeners on most of the other stringers to make them less susceptible to temperature-induced damage. There were no obvious signs of trouble Thursday.
Assuming an on-time docking on Saturday, Captain Drew and Captain Bowen plan two spacewalks, Monday and Wednesday. The new storage module will be attached to the station on Tuesday. The flight plan calls for Discovery to undock from the station on March 5 at 7:44 a.m. and land back at the Kennedy Space Center on March 7 at 12:44 p.m.
But United States and Russian flight controllers are expected to approve what amounts to an out-of-this-world photo opportunity: The idea is to add a day to Discovery’s mission so that three station crew members can venture out in a Russian Soyuz spacecraft to photograph the completed station with a shuttle attached, along with European, Japanese and Russian spacecraft.
If the fly-around is approved, Discovery will undock March 6 and land in Florida around 11:35 a.m. on March 8.
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