CAPE CANAVERAL, Fla. - NASA mission managers gave a preliminary approval late Tuesday for the planned Dec. 7 launch of the space shuttle Discovery, even as engineers wrangle two issues that came up during routine inspections.

"We're on track and on target for Thursday," said LeRoy Cain, NASA's space shuttle program launch integration manager, in a launch readiness briefing held here at Kennedy Space Center. "All in all, we're in great shape."

Discovery is slated to lift off with seven astronauts at 9:35:47 p.m. EST (0235:47 Dec. 8 GMT) toward the International Space Station (ISS) for a 12-day construction mission. The STS-116 mission's launch window runs from Dec. 7 to 17, with the possibility that it could be extended further if NASA managers decide to allow the mission to run over the New Year.

Launch engineers are looking into a brief power surge in a main circuit used in switching power from the Discovery's Mobile Launcher Platform to the orbiter and a potentially problematic adhesive on the shuttle's reusable solid rocket motor's pressure seal.

"With respect to the solid rocket motor joint adhesive, I don't think I would even call it suspect because I don't know enough to be able to even put an adjective or a characterization of it," Cain said. "What we know is there is a test out there, or the results of a test, which potentially we need to look further at and determine whether or not we have any concerns."

It is currently unknown whether either issue could affect launch but more information is expected during a 1:00 p.m. EST (1800 GMT) shuttle manager meeting set for Wednesday.

"We don't even know if we have a concern," Cain said. "I wouldn't want to speculate, really, on either one of those problems and where they might lead, but you can be sure we'll follow the data."

Led by commander Mark Polanksy, the seven-member crew of STS-116 are tasked with delivering a new portside piece of the orbital laboratory and rewiring the station's electrical grid. Mission specialists Sunita Williams will also relieve ESA astronaut Thomas Reiter who has been aboard the station since July.

The weather outlook for Discovery's launch day also deteriorated from 80 percent favorable on Monday to 60 percent by Tuesday evening. The main concern is a cold front expected to pass through the launch area Thursday that could bring with it lingering cloud cover, explained Air Force 1st Lt. Kaleb Nordgren of the 45th Weather Squadron.

Strong winds are expected at Kennedy on Friday and Saturday, bringing a 60 percent chance launch attempts could be scrubbed on both days.

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