NASA stands ready to pick up the countdown to launch of Discovery's final flight after successfully fixing a gas leak associated with the orbiter's right-hand rocket pod.The launch was pushed to Wednesday after leaks of gaseous nitrogen and gaseous helium were detected when engineers began to pressurize propellant tanks in the shuttle's Orbital Maneuvering System, which comprise twin engines housed in hump-like pods that straddle the shuttle's vertical stabilizer, or tail fin.
NASA Test Director Steve Payne said technicians successfully swapped out suspect seals and repressurized the system, clearing the way for countdown to begin at 2 p.m. today.
"That is behind us, fortunately," Payne said.
Call To Stations in Firing Room 4 of the Launch Control Center is set for 1:30 p.m.
Kathy Winters, shuttle weather officer with the Air Force 45th Space Wing, said there is a 70 percent chance conditions will be acceptable for launch at 3:52 p.m. Wednesday, the middle of a 10-minute window to put Discovery and six astronauts on course for a rendezvous and docking with the International Space Station.
The weather on Thursday is expected to degrade, with only a 60 percent chance of acceptable conditions. On Friday, the percentage rises to 70 percent again.
NASA must launch by next Sunday or delay until December at the earliest. The sun angle on the station between Nov. 8 and Nov. 23 will be such that the outpost could not generate enough electricity or dispel enough heat to support a docked shuttle. A three-person Soyuz crew is departing the station in late November and another three-person crew is flying up in mid-December. NASA would have a short launch opportunity between those missions.
ABOUT THE IMAGE: Click to enlarge the NASA image of Discovery's final flight crew at launch pad 39A earlier this month. From left to right are mission commander Steve Lindsey, pilot Eric Boe and mission specialists Alvin Drew, Tim Kopra, Michael Barratt and Nicole Stott. Photo credit: NASA/Kim Shiflett
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