CAPE CANAVERAL, Fla. -- NASA managers announced Thursday that they would press ahead with the first space shuttle launch of the year next week, three months later than originally planned because of a hail storm that pockmarked the spacecraft's external tank.
After a two-day meeting at the Kennedy Space Center, NASA officials agreed to launch Atlantis at 6:38 p.m. June 8 to deliver a new pair of solar arrays to the international space station.
"The team is really pumped to get this done this time," said Mike Leinbach, NASA launch director. "We've been doing three months of down time due to the hail storm."
The launch had been set for mid-March, but the storm dropped golf ball-sized hail on the launch pad and damaged insulating foam on the external tank.
NASA managers are especially cautious when it comes to the external tank since a piece of foam fell off Columbia's tank in 2003 and hit the spacecraft's wing. Damage from the impact allowed fiery gases to penetrate Columbia during descent, killing all seven astronauts aboard.
After the hail storm, Atlantis was rolled back to the Vehicle Assembly Building, where technicians painstakingly repaired thousands of gashes in the tank's foam.
"We are extremely confident that we have done perfectly good repairs and have a tank that is safe to fly," said space shuttle program manager Wayne Hale.
Engineers have put the probability of foam coming off a failed repair area and causing critical damage to the shuttle at 1 in 650, Hale said, but "probability numbers I would take with a good grain of salt."
"All of that is good as a management tool," he said. "But I wouldn't take any of those numbers to the bank as a real indication of where you would put your money on the roulette wheel in Las Vegas."
Although a final polling of managers was unanimous to go ahead with a launch attempt, managers initially argued over whether bolt parts that hold in place pumps in the shuttle's main engines should be replaced because there was evidence that they could corrode with age. They eventually concluded that the pumps on Atlantis weren't old enough to have that problem and that an inspection of Atlantis' pumps had turned up nothing.
The postponement of Atlantis' launch forced NASA to cut the expected number of shuttle flights this year from five to four and pushed back the flight schedule for the rest of the year.
Astronaut Clayton Anderson was added to the previously six-person Atlantis crew so he can replace U.S. astronaut Sunita Williams on the space station. Otherwise, Williams would have spent eight months at the station, instead of the more typical six months. Her original return trip to Earth aboard shuttle Endeavour was pushed back from early July to late August.