(04/25/2001) --- Workers in the Space Shuttle Main Engine Processing Facility oversee the movement of a new Space Shuttle main engine (block 2 engine) toward the transport vehicle in the foreground. The engine will be moved to the Orbiter Processing Facility and installed for its first flight on the orbiter Atlantis, on mission STS-104. The Block II Main Engine configuration is manufactured by Boeing Rocketdyne in Canoga Park, Calif., and includes a new Pratt & Whitney high-pressure fuel turbo pump. Engine improvements are managed by NASA’s Marshall Space Flight Center in Huntsville, Ala. Each Space Shuttle Main Engine is 14 feet (4.3 meters) long, weighs about 7,000 pounds (3,175 kilograms), and is 7.5 feet (2.3 meters) in diameter at the end of the nozzle.