The space shuttle Discovery is prepared for transport in the Vehicle Assembly Building before rolling to launch pad 39B at the Kennedy Space Center in Cape Canaveral, Florida May 19, 2006. Discovery is scheduled for launch in July(Xinhua/Reuters)

    WASHINGTON, May 19 (Xinhua) -- NASA on Friday rolled space shuttle Discovery to the launch pad at the Kennedy Space Center in Florida, in preparation for a second test flight since the 2003 Columbia disaster.

    The trip of about 6.5 km from the Vehicle Assembly Building took nearly eight hours.

    The launch window is between July 1 and July 19.

    Shuttle program manager Wayne Hale said he was confident that Discovery would fly in July and NASA could complete another two flights within this year.

    Insulation foam falling off the shuttle's external fuel bank doomed Columbia in 2003.

    Despite expensive fuel tank modifications, the problem re-emerged during Discovery's liftoff last July in the first flight since the Columbia disaster, forcing the shuttle fleet to be grounded again.

    The incident led to redesigns of the fuel tank. NASA engineers are still testing the improvements.

    Hale said an initial review of the data appeared to be good. NASA will not make a final decision until mid-June on whether to launch Discovery in July. Enditem