CAPE CANAVERAL, Fla. – NASA (search) pushed back next month's launch of Discovery by a full week, saying Wednesday it needs more time to complete testing and engineering work for the first space shuttle flight since the Columbia disaster (search).
The new launch date is May 22.
"I'm very confident that the team has their arms around this, and we know exactly what we have to do to get to the May 22 timeframe," shuttle program manager Bill Parsons said, referring to the remaining engineering analysis and paperwork.
NASA had been hoping to send Discovery (search) on a 12-day delivery and repair mission to the international space station on May 15.
But a critical design review of the revamped shuttle was not held until this week, and all the information needs to be submitted to the task force overseeing the space agency's return-to-flight effort.
Wayne Hale, Parsons' deputy, said NASA has analyzed more than 170 potential debris sources from the shuttle and external fuel tank, and eliminated concerns that they might cause serious damage at liftoff, as was the case for Columbia in 2003. But a few sources still need more study: ice that can form on the tank once it is filled with super-cold fuel, and foam at the top of the tank.
Another remaining hurdle involves the brand-new inspection boom that Discovery's astronauts will use to check their spacecraft in orbit for any damage from launch debris. Engineers are double-checking to make sure the boom can withstand the vibrations and stresses of liftoff.
NASA officials stressed that the mid-May liftoff date was only a target and that the space agency is not going to allow itself to be rushed.
"While it would be nice and we're certainly working toward May, we're going to launch when we're ready to launch and not before," Hale said.
NASA has until early June to launch Discovery — a window dictated by the space station's position and NASA's desire for a daylight launch. Otherwise, the flight will have to wait until July.
The space agency has decided that the first two post-Columbia launches will be held in daylight to ensure good photography of the shuttle and its fuel tank, which has been modified to prevent big pieces of foam insulation from coming off.
A 1.67-pound chunk of foam broke off Columbia's fuel tank during liftoff in January 2003 and gashed the left wing. The hole caused the spacecraft to shatter during re-entry two weeks later, killing all seven astronauts.