Space shuttle Discovery backs out of the Vehicle Assembly Building, or VAB, at NASA’s Kennedy Space Center in Florida, for its trip to the Shuttle Landing Facility, or SLF. Discovery was in storage in the VAB’s high bay 4 awaiting departure from Kennedy’s Launch Complex 39 area for the final time. At the SLF, Discovery will be hoisted onto a Shuttle Carrier Aircraft, or SCA, with the aid of a mate-demate device. The SCA, a modified Boeing 747 jet airliner, is scheduled to transport Discovery to the Washington Dulles International Airport in Virginia on April 17, after which the shuttle will be placed on permanent public display in the Smithsonian National Air and Space Museum's Steven F. Udvar-Hazy Center.