One of NASA’s most familiar and recognizable aircraft, Space Shuttle Carrier Aircraft No. 905, has departed NASA’s Dryden Flight Research Center for the final time, ending a 38-year association with the NASA field center at Edwards, Calif.
SCA pilots Jeff Moultrie and Bill Rieke and long-time SCA flight engineer Henry Taylor from NASA’s Johnson Space Center flew the modified Boeing 747 jetliner from Dryden to Ellington Airport in southeast Houston Oct. 24, where the big Boeing will be retired and eventually placed on public display.
An early-model 747-123 version, SCA 905 was the 86th 747 built, rolling out of the Boeing plant in 1970 and making its first flight on Oct. 15 that year. After serving as a flagship jetliner for American Airlines for several years, the jumbo jet was acquired by NASA’s Johnson Space Center in 1974 for the coming Space Shuttle Program.
Prior to its conversion into a Shuttle Carrier Aircraft, the jetliner was the focus of several aeronautical research experiments conducted at NASA’s Flight Research Center, including wake vortex turbulence studies that aided the Federal Aviation Administration in modifying airport approach and departure procedures for aircraft flying behind large commercial aircraft.
NASA 905 then underwent significant structural changes and upgrades by Boeing per NASA specifications in 1976 to prepare it for the role it would have for the next 35 years. These modifications included beefing up the fuselage and installation of the three shuttle mounting support structures, installation of vertical fins at the ends of the horizontal stabilizer to aid stability when carrying a space shuttle, installing upgraded JT9D-7J engines, removal of most interior furnishings and installation of shuttle-specific instrumentation.
Modifications to the 747 included beefing up the aircraft structure and installing attach points for the space shuttle orbiter and installing a flight-crew escape system, consisting of an exit tunnel extending from the flight deck to a hatch in the bottom of the fuselage and a pyrotechnic system to activate the hatch release and cabin window release mechanisms. They also included vertical fins mounted at the ends of the horizontal stabilizer to aid stability when carrying a space shuttle, upgraded JT9D-7J engines, removal of most interior furnishings and installation of shuttle-specific instrumentation.
The converted jetliner was then returned to Dryden to serve as a launch aircraft for the prototype shuttle orbiter Enterprise during the Approach and Landing Test program in 1977. The flight crew escape system was removed following the successful completion of the ALT program.
NASA 905 was then modified again from ALT launch to ferry flight configuration, and flew four ferry test flights before being placed into service to ferry the shuttle orbiters. Although the primary function of the SCA was to transport the orbiters to Kennedy Space Center from Dryden, or other contingency landing sites, the aircraft also carried shuttles to and from Palmdale for modifications and maintenance. NASA 905 also ferried the Enterprise for display at special events such as the Paris Air Show in France and the 1984 Worldís Fair in New Orleans, La.
NASA 905 flew 70 of the 87 ferry flights during the operational phase of the shuttle program, including 46 of the 54 post-mission ferry flights from Dryden to the Kennedy Space Center. After the orbiters were retired, NASA 905 flew three ferry missions in 2012 to deliver the shuttles Discovery, Enterprise, and Endeavour to museums where they are currently on display.
After delivering Endeavour to Los Angeles International Airport on Sept. 21, 2012 where the shuttle was turned over to the California Science Center, NASA 905 was flown back to NASA Dryden from Los Angeles, completing her service to the Space Shuttle Program. SCA 905 was then flown from Dryden to Ellington Airport in Houston where the Johnson Space Center’s aircraft operations are based on Oct. 24, 2012.
During its 42-year flight career, both as a commercial jetliner and as a NASA space shuttle carrier, SCA 905 amassed 11,017 flight hours and made 6,334 takeoffs and landings. Although the SCA remains in flyable condition as of mid-November, Taylor reported that a decision on its future use or retirement is still pending.
NASA’s second Shuttle Carrier Aircraft, No. 911, was acquired used from Japan Air Lines in 1989 and after being modified for its new role, was delivered to NASA in late 1990. It was retired in early 2012 after 386 flights as a NASA shuttle carrier aircraft, 66 of which were ferry flights with a space shuttle mounted on atop the fuselage.
NASA 911 remains parked at the NASA Dryden Aircraft Operations Facility adjacent to Air Force Plant 42 in Palmdale, Calif. It is available as a source of potential spare parts to support NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA), a highly modified Boeing 747SP that carries a 100-inch infrared telescope on astronomical science missions around the globe.
Both SCAs were owned by the Johnson Space Center, although they were based at NASA Dryden during much of their NASA service.