Leak postpones shuttle launch

Mar 11, 2009 2 min read

CAPE CANAVERAL (AP) – Hit by more valve trouble, NASA postponed the launch of space shuttle Discovery just hours before it was to head to the international space station Wednesday because of a hydrogen gas leak.

The potentially catastrophic leak was in a different part of the system that already had caused a vexing one-month delay.

Shuttle managers put off the launch until at least Sunday and indicated that Monday might be more likely.

The latest delay means Discovery’s two-week flight must be shortened and some spacewalks cut out of the mission. That’s because Discovery needs to be gone from the space station before a Russian Soyuz rocket blasts off March 26 with a fresh station crew.

If Discovery isn’t flying by Tuesday, it will have to wait until April. That almost certainly would bump the succeeding space shuttle missions as well as plans to double the size of the space station crew at the end of May, said Mike Moses, chairman of the mission management team.

Mission Control radioed the news to the three space station residents Wednesday evening. Commander Mike Fincke took it in stride, saying he’d rather see the shuttle this month than next.

“But more importantly, we’d rather see it up safely, so we understand,” Fincke said.

NASA does not want a shuttle at the space station at the same time as a newly arrived Soyuz because of the tremendous workload it would put on all the crews.

The gaseous hydrogen began leaking just as the launch team was close to wrapping up the loading of Discovery’s external fuel tank for a late-night liftoff. The seven astronauts had yet to board the spaceship.

Launch director Mike Leinbach said the problem appears to be with a valve in the fuel tank for venting hydrogen gas overboard. Whenever the valve was opened to relieve pressure in the tank, hydrogen gas leaked out into the air.

In the past, the problem would go away with a simple closing and reopening of the valve.

“This time it didn’t,” Leinbach said. He noted that this was the largest such leak ever detected.