U.S. space shuttle ready to deliver Japanese porch

By Irene Klotz

CAPE CANAVERAL, Florida (Reuters) - NASA prepared to launch space shuttle Endeavour to the International Space Station on Saturday to deliver a Japanese porch and spare parts needed to keep the outpost going after the shuttle fleet's retirement next year.

The space agency planned to begin fueling the ship just after 10 a.m. for liftoff from the Kennedy Space Center in Florida at 7:39 p.m..

NASA tried twice last month to launch Endeavour, but was stymied by potentially dangerous hydrogen fuel leaks.

Engineers discovered a misalignment in a line that vents hydrogen from the fuel tank as it is being filled. Technicians made repairs and tested the work last week.

"I have extremely high confidence" in the repair, said Mike Moses, who oversees the shuttle program at the Kennedy Space Center.

The only issue may be the weather. Meteorologists on Friday predicted a 60 percent chance that thunderstorms and rain would be too close to the launch site for Endeavour to fly.

"I don't worry about things I can't control and I certainly can't control the weather," Moses said.

NASA is running out of time to finish the station and retire the shuttle fleet by September 30, 2010, as directed by Congress. Managers say they will not compromise safety for schedule and will ask for an extension and more funding if necessary to complete the outpost, a $100 billion project of 16 nations.