Hydrogen Leak Delays Space Shuttle Launch

By Brian Wagner

13 June 2009

NASA officials have postponed the launch of shuttle Endeavour after discovering a hydrogen gas leak a few hours before lift-off. Officials say the same problem delayed a shuttle launch in March.

Space shuttle Endeavour is revealed on Launch Pad 39A at NASA's Kennedy Space Center in Florida following rollback of the rotating service structure.

Officials halted the launch countdown when they discovered the leak shortly after midnight at Kennedy Space Center in Florida. They said sensors on the launch pad detected a significant amount of hydrogen gas escaping during the fueling process.

Launch director Mike Leinbach said hydrogen is very volatile and can burn, even in small concentrations.

"We are very, very sensitive to hydrogen on the ground," he said. "[We want] to make sure it is sealed properly at liftoff so we are not venting overboard and possibly run into a situation where we did not have enough hydrogen in the tank going uphill [entering orbit]."

Engineers are not expected to begin work on finding the leak until Sunday.

A similar leak delayed the launch of shuttle Discovery three months ago. NASA technicians replaced one connector to stop the leak, but officials say they never uncovered the actual cause of the problem.

Officials said it is unclear when the Endeavour mission can be rescheduled or how long it will take engineers to figure out what is causing the leak and how long it will take to fix it.

Chairman of the mission management team, Mike Moses, said there are several other space missions readying for launch in coming weeks.

"If the team is ready to go on the 17, we do not have the [launch] range that day, so I would have to negotiate with the Atlas and the LRO mission so we could have the range," he said.

The LRO, or Lunar Reconnaissance Orbiter, is set to launch on the 17th to study landing sites and other conditions for future manned missions to the moon.

The plan for shuttle Endeavour calls for a 16-day mission to deliver the final segment of a new Japanese built lab and other supplies to the International Space Station.