Saturday, June 13, 2009
By MARCIA DUNN,AP Aerospace Writer AP - 52 CAPE CANAVERAL, Fla. - NASA delayed the launch of space shuttle Endeavour on Saturday because of a hydrogen gas leak similar to one that cropped up three months ago.
The countdown was halted shortly after midnight, about 2 1/2 into the fueling of the external tank and less than seven before the planned launch. The astronauts had not yet suited up.
Mission managers planned to meet later Saturday morning to decide when to try another launch attempt for the space station construction mission.
The leak is similar to one the space agency faced in March during the launch countdown of Discovery. That flight ended up being delayed by four days because of the leak and forced NASA to shorten Discovery's flight by a day and eliminate a space walk.
'It has a similar signature to what happened in March,' said NASA spokesman Allard Beutel.
The launch team planned to drain the external fuel tank while trying to figure out what went wrong. In March, the leak occurred where a vent line hooks up to the tank. The hookup was replaced along with a couple seals, and the seepage stopped.
NASA is up against a tight deadline. Endeavour must lift off by Monday, otherwise the shuttle has to get in line behind a moon-bound spacecraft that's due to rocket away Wednesday. And if the shuttle isn't flying by June 20, it will have to wait until mid-July because of unfavorable sun angles that would make the ship too hot while docked at the international space station.
During the 16-day mission, Endeavour and its crew of seven are supposed to deliver the final segment of Japan's huge space station lab, along with some spare parts for the orbiting outpost and more than 600 pounds of food for the six men living there.
When Endeavour pulls up, there will be 13 people together in orbit for the first time.
Of the seven shuttle astronauts, only one is a woman, a Canadian. The rest of the crew are U.S. citizens. On board the space station, the crew is more international. The six occupants, all men, represent Belgium, Canada, Japan and Russia, as well as the United States.
'It's like having your family descend on you for the holidays, right? And they're going to stay for a very long time when they come and they're bringing all their stuff,' observed Mike Moses, chairman of NASA's mission management team.
Endeavour and its crew will spend 11 1/2 days at the space station. Five spacewalks are planned.
If Endeavour flies this month, its arrival will come at a particularly busy time for the space station. The station crew doubled in size late last month; that's taken some adjustment for everyone involved. Then just a week ago, two of the crew went out on a spacewalk. Earlier this week, the two put their spacesuits back on and went into the air lock to work on a docking hatch.
NASA is pushing to launch Endeavour as soon as possible because of the tight lineup of shuttle flights over the next 1 1/2 years. The space agency is under presidential direction to retire its three remaining shuttles and complete the station by the end of 2010 if possible.
Eight shuttle missions remain, including Endeavour's upcoming trip. Each one is dedicated to finishing the station, currently 81 percent complete, and hauling up supplies, spare parts and experiments.
The space station will be supplied over the long haul by unmanned Russian, European and Japanese craft, but none as big as the shuttle. That's why NASA needs to deliver large spare parts now, while the shuttles are still flying.
Until NASA's new spaceship is ready to carry passengers _ which isn't expected to happen before 2015 _ U.S. astronauts will hitch rides back and forth on the cramped Russian Soyuz spacecraft for up to $51 million a person.
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