Related: Discovery rolled to launch pad

    WASHINGTON, May 31 (Xinhua) -- The space shuttle Discovery passed a critical technical review for a July launch and the risks from falling foams have been cut to an acceptable level, NASA officials said Wednesday.

    "We have found no show stoppers," NASA shuttle program manager Wayne Hale told reporters after a two-day meeting involving 100 engineers and managers to discuss the risks from falling insulation foams from the shuttle's external fuel tank, as happened in the Columbia disaster and during the flight of Discovery on the first post-accident mission last July.

    Hale said that the risk from falling foam is acceptable and any debris would be smaller than the 0.5-kg piece that fell off Discovery last year.

    The biggest change in the external fuel tank's design for the July flight is the removal of 16.7 km of insulation foam, but some foams will still peel off, most likely from 34 areas called ice-frost ramps, Hale said.

    He said NASA will make further improvement to the tank for future flights to eliminate the danger posed by debris from the ramps.

    Space shuttle Discovery was rolled to the launch pad at the Kennedy Space Center in Florida on May 19 for the liftoff between July 1 and July 19 to the International Space Station. Two more technical reviews are upcoming before the shuttle clears all the hurdles for its second flight since the 2003 Columbia disaster.

    Seven astronauts died in the Columbia disintegration upon re-entering the Earth's atmosphere on Feb. 1, 2003. The disaster was caused by a large chunk of foam falling from the shuttle's external fuel tank. Enditem