NASA managers 'go' for repaired shuttle Discovery's final launch

CBS News

KENNEDY SPACE CENTER, Fla. -- With good weather expected, NASA managers Wednesday cleared the shuttle Discovery for launch Thursday on a long-delayed space station resupply mission, the orbiter's 39th and final flight.

The space shuttle Discovery, awaiting launch Thursday on its 39th and final mission. (Credit: Spaceflight Now/Stephen Clark)
Mike Moses, the shuttle integration manager at the Kennedy Space Center, said Discovery's countdown was proceeding smoothly with no technical problems of any significance at pad 39A.

"Today we held our launch minus-one-day mission management team meeting where we got together just to discuss our current status and our readiness," he told reporters. "Everything is on track, going beautifully with the countdown and we are more than ready for tomorrow's launch."

Discovery is scheduled for liftoff at 4:50:27 p.m. EST (GMT-5), the middle of a 10-minute window that roughly coincides with the moment Earth's rotation carries the launch pad into the plane of the International Space Station's orbit. The shuttle must launch within five minutes of that "in-plane" time to reach the lab complex.

Shuttle weather officer Kathy WInters said forecasters are continuing to predict an 80 percent chance of good weather. The outlook deteriorates slightly over the next few days as a frontal system moves through the area, with the odds dropping to 70 percent "go" Friday and 60 percent on Saturday.

The primary goals of the 133rd shuttle flight are to deliver supplies, science gear, spare parts and other equipment to the space station, along with a final U.S. module that will be used as an orbital storage depot.

"We've been ready from a mission standpoint for quite a while, now our hardware's in line and ready to go," Moses said. "We're delivering the PMM, the permanent Multi-purpose Module, which will be basically a really good addition to space station in terms of storage capability on orbit.

"We're taking up the ELC-4, external logistics cargo pallet, which has a spare radiator and room for other spare hardware once it gets on orbit and stowed on the station. We have two very busy EVAs (spacewalks) to clean up a lot of (unfinished) activities and prepare the station for the future."

The astronauts also will deliver science hardware and a variety of experiments, along with a humanoid technology demonstration robot known as Robonaut 2.

"So we're really looking forward to a very action-packed, successful mission and everything's on track," Moses said.

Launch originally was planned for last Nov. 1, but the flight was delayed by technical problems, bad weather and ultimately by cracks in the ship's external tank. The cracks have since been repaired and structural stiffeners were added to make rib-like stringers less susceptible to stress-relief fractures.

Launch Director MIke Leinbach said figuring out the root cause of the cracks was one of the most challenging realtime shuttle problems in the 30-year history of the program. But "we fixed the tank, we're going to fly it tomorrow and it's going to perform perfectly fine."

Discovery is NASA's most seasoned orbiter and it will be making its final voyage Thursday, followed by the final flight of Endeavour in April and Atlantis later this summer.

Asked if emotions were running high going into Discovery's final launch count, Leinbach said "the last flight of all three vehicles is going to be emotional for all of us."

"Landing day's going to be tough," he said. "Landing day of Discovery, and then Endeavour and especially Atlantis, the last mission, you'll see a lot of people on the runway who will probably choke up some. Because it's the end of a 30-year program that not only have we worked in and made our livelihoods in, but we've grown to love and appreciate and feel like we're doing something special for the country and, really, the world. And it's coming to an end, and that's tough.

"But we're going to do it right, we're going to approach each of these three flights the way we approached all the other ones, we'll pull them off and be able to look back and be very, very proud of what we've accomplished in the shuttle program."