&to=http:// english.pravda.ru/science/19/94/378/12181_.html ' target=_blank>NASA has postponed the move of space shuttle Discovery back to its assembly building so workers can inspect it for cracks on the landing gear.
Last week, a small crack was found on the right main landing gear of the &to=http:// english.pravda.ru/world/2001/02/21/2629.html ' target=_blank>shuttle Atlantis and NASA wants to make sure Discovery doesn't have the same problem.
Officials also wanted to make sure the landing gear of the fleet's two other shuttles are free of cracks before July, when Discovery is scheduled to become the first shuttle to launch since the fatal Columbia disaster in 2003, reports ABC News.
Discovery was due to be returned to the assembly hangar on Tuesday so workers could swap its external fuel tank and twin booster set with new equipment that is already partly outfitted for an extra heater to melt ice buildups on the tank.
Managers decided to delay Discovery's targeted launch in May to upgrade the tank, which has been the primary focus of NASA's efforts to return the shuttle fleet to flight.
Columbia disintegrated as it flew through the atmosphere to land, killing seven astronauts, because of a hole in its wing caused when a piece of foam insulation fell off the tank and struck the shuttle during liftoff. Engineers are concerned ice buildups could present a similar hazard.
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