NASA, the United States' Space Agency, has previously employed two modified Boeing 747 airliners in its fleet, used to transport its Space Shuttle orbiters. These two aircraft were two different variants of the Boeing 747, and were often used on different missions. Both Shuttle Carriers have been retired by NASA since 2012; however, they have both been preserved and are on display to the public.

N905NA

N905NA is a Boeing 747-100 that NASA used to transport its Space Shuttle orbiters. The aircraft was initially delivered to American Airlines in 1970 with the registration N9668. However, subsequently, the aircraft was transferred from American to NASA in July 1974, and its registration was changed to N905NA. The aircraft was initially purchased by NASA for the research of trailing wake vortex research. NASA then decided to convert the aircraft to carrying space shuttles.

The retired Queen has four Pratt & Whitney engines and is currently stored at the Space Center Houston in Clear Lake, TX. Since 2014, the Space Center has mounted a replica space shuttle above the Boeing 747 to demonstrate its use.

Shuttle Carrier Aircraft N911NA on display in Palmdale, CA in June 2015
The N911NA is currently still parked in Palmdale, CA. Photo: Darkest tree via Wikimedia Commons.

N911NA

N911NA is a Boeing 747SR that NASA acquired from Boeing. The aircraft was first delivered in September 1973 as JA8117 to Japan Airlines. Ownership was then transferred first to Boeing Aircraft Holding Company in April 1988 as N747BL, and then to NASA in October 1988 as N911NA. The fate of the aircraft is similar to that of N905NA. Following the aircraft's retirement in 2012, it was moved to Joe Davies Heritage Airpark in Palmdale, CA, and remains on display to the public.

Design and Development

The Boeing 747 was not NASA's initial choice for its Space Shuttle Carrier. NASA first considered the Lockheed C-5 Galaxy, but thought that the Boeing 747's low wing design was more suitable. In addition, NASA would be able to outright own the Boeing 747, whereas the Lockheed C-5 Galaxy would be on loan from the US Air Force.

Space shuttle Atlantis on carrier 747
The Shuttle Atlantis was mounted on N905NA during a flight. Photo: NASA / Carla Thomas via Wikimedia Commons.

Following the purchase of N905NA from American Airlines and NASA's trailing wake vortex research, NASA commissioned Boeing to make substantial modifications to the aircraft. The rows of seats towards the back of the aircraft were all removed, while the first class seats were retained for NASA staff during actual flights. In addition, the fuselage of the aircraft was stretched.

Operations

N905NA was often used to ferry space shuttles between different NASA installations. Most ferry flights were from Edwards Air Force Base to Kennedy Space Center. However, following the Challenger Disaster in 1986, NASA made the decision to acquire an additional Boeing 747, which was registered as N911NA. These two aircraft were largely the same, except the top deck of the 747 was shorter on the N905NA compared with the N911NA.

Shuttle Independence and NASA N905NA at Space Center Houston
The Boeing 747 and the Space Shuttle are currently stored in Space Center Houston. Photo: Romain2k via Wikimedia Commons.

Retirement

Following the conclusion of NASA's Space Shuttle Program in 2011, the two iconic Boeing 747 shuttle carrier aircraft were retired. N911NA was retired on February 8th, 2012, after a final flight to Edwards Air Force Base in Palmdale, CA. It was then moved to Joe Davies Heritage Airpark in Palmdale. N905NA, on the other hand, was used to deliver the space shuttles to museums where they would be stored. In 2013, NASA decided to store the aircraft in Houston, TX, with the mockup shuttle Independence to show visitors the legacy of the Space Shuttle Program.