Shuttle Carrier Aircraft

Shuttle Carrier Aircraft. The Shuttle Carrier Aircraft were two extensively modified Boeing 747 jetliners used by NASA to transport Space Shuttle orbiters. Primarily operated from 1977 to 2012, these unique aircraft ferried shuttles from landing sites back to the Kennedy Space Center launch complex and between various NASA facilities. Their most visible role was piggybacking the orbiters, creating one of the most iconic images of the Space Shuttle program.

Overview

The requirement for a Shuttle Carrier Aircraft emerged from the Space Shuttle's design, which lacked the fuel capacity for transcontinental flights under its own power after atmospheric reentry. NASA initially acquired a second-hand Boeing 747-100 from American Airlines in 1974 for approach and landing tests of the prototype orbiter Enterprise. Following the success of these tests, a second aircraft, a Boeing 747-100SR formerly operated by Japan Airlines, was purchased in 1988 to support the expanding shuttle fleet. The primary operating bases were Edwards Air Force Base in California and the Shuttle Landing Facility at Kennedy Space Center in Florida.

Design and modifications

The airframes, originally standard commercial Boeing 747 models, underwent significant structural modifications by Boeing to fulfill their specialized mission. The most prominent alteration was the addition of three external attach points on the upper fuselage to secure the orbiter, which weighed over 100,000 pounds. To counteract the aerodynamic effects and weight of the orbiter, the aircraft were fitted with vertical stabilizer endplates on the horizontal stabilizers for enhanced directional stability. All interior furnishings and amenities were stripped out, and the fuselage was strengthened with internal truss structures. The original Pratt & Whitney JT9D engines were eventually replaced with more powerful and efficient Pratt & Whitney JT9D-7J engines to handle the increased gross weight, which could exceed 700,000 pounds during ferry flights.

Operational history

The operational history of the Shuttle Carrier Aircraft is intrinsically linked to the milestones of the Space Shuttle program. The first aircraft, designated NASA 905, began its service with the 1977 Approach and Landing Test program involving the orbiter Enterprise. Following the STS-1 mission in 1981, it routinely ferried orbiters like Columbia, Challenger, Discovery, Atlantis, and Endeavour from Edwards Air Force Base to Florida. The second aircraft, NASA 911, entered service in 1991 and was primarily used to ferry the newer orbiters Discovery and Endeavour. Their missions included not only post-landing ferry flights but also delivery of new orbiters from their assembly site in Palmdale, California and transport to major modification facilities.

List of Shuttle Carrier Aircraft

Two aircraft served in the role: * **NASA 905 (N905NA)**: A Boeing 747-100 purchased from American Airlines (originally registered N9668). It was the first SCA and carried all orbiters during its career, including Enterprise and Columbia. * **NASA 911 (N911NA)**: A Boeing 747-100SR (Short Range) purchased from Japan Airlines (originally registered JA8117). It entered service later and primarily supported the orbiters Discovery and Endeavour.

Retirement and display

Both Shuttle Carrier Aircraft were retired following the conclusion of the Space Shuttle program in 2011, with their final ferry flights occurring in 2012. NASA 905 was flown to Ellington Field in Houston, Texas, where it is now on permanent display alongside the replica shuttle Independence at Space Center Houston. NASA 911 was delivered to the Joe Davies Heritage Airpark in Palmdale, California, the city where the orbiters were assembled, for public display. Their retirement marked the end of a unique chapter in aerospace logistics, where two of the world's most recognizable flying machines were combined for a critical support role in human spaceflight.

Category:NASA aircraft Category:Boeing 747