NASA Clears Shuttle Atlantis for Friday Launch

CAPE CANAVERAL, Fla. -- Preparations for a Friday evening liftoff of the shuttle Atlantis are still on track despite weather forecasts of possible hail in the days leading up to launch.

"We feel very good about where we are with Atlantis," shuttle launch integration manager LeRoy Cain said Wednesday following a mission management review. "We're ready to go and the team is ready to go and we're just really excited to be at this point after a long and arduous spring."

Atlantis was originally set to launch March 15, but was delayed due to hail damage to the orbiter's foam-covered external tank following a late-February storm.

NASA's seven-astronaut crew now plans to launch Atlantis' STS-117 construction mission to the International Space Station on Friday, June 8 at 7:38 pm EDT (2338 GMT).

"Right now all looks good," said shuttle launch director Mike Leinbach. "Countdown is going well, no issues to report, and we're looking forward to an on time launch Friday night."

Mission managers also found that the discovery of a slightly misaligned umbilical cord connected to a fuel tank planned for use by the shuttle Endeavor in August will not affect plans for Atlantis' space shot.

For Atlantis, ?we reviewed the data, we did some analysis?and determined that we are ready to go fly with the system that we have on the launch pad," Cain said. ?We have a very solid flight rational and so we are very comfortable with where we are with that mission.?

Weather concerns

Weather forecasters predict a 30 percent chance that thunderstorms could delay Friday's launch, and that possibility is expected to increase to 40 percent on Saturday and Sunday.

"We are expecting thunderstorms to occur over the next couple days during the afternoon, but they should progressively move to our west and clear out of Kennedy Space Center by launch day," said Pat Barrett of the U.S. Air Force 45th Weather Squadron.

There is also a possibility of half-inch hail and strong winds of over 55 mph (92km/h) in the days leading up to launch, Barrett said.

Leinbach said NASA is prepared to deal with that scenario should it occur.

"We'd kick off another round of inspections," he said. "We would ask each project to go and inspect their hardware just like we did three months ago, especially the external tank. Those inspections would likely take many, many hours. Would that cause a delay? I'm not prepared to say right now."

NASA's STS-117 crew, led by shuttle commander Rick Sturckow, is tasked with installing a new pair of solar array and trusses on the orbital laboratory.

Atlantis has an open launch window from June 8 to 12. After that, it will have to stand down to allow the scheduled launch of a Lockheed Martin Atlas rocket on June 14. The next launch window would then begin on June 17 and extend through mid-July.

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