Shuttle Carrier Aircraft


Shuttle Carrier Aircraft
Shuttle Carrier Aircraft
NASA's Shuttle Carrier Aircraft 905 (front) and 911 (rear)
Role Outsize cargo freight aircraft
Manufacturer Boeing (aircraft & modifications)
Introduction 1977
Primary user NASA
Number built 2
Developed from Boeing 747-100

The Shuttle Carrier Aircraft (SCA) are two extensively modified Boeing 747 airliners that NASA uses to transport Space Shuttle orbiters. One is a 747-100 model, while the other is a short range 747-100SR.

The SCAs are used to ferry space shuttles from landing sites back to the Shuttle Landing Facility at the Kennedy Space Center, and to and from other locations too distant for the orbiters to be delivered by ground transport. The orbiters are placed on top of the SCAs by Mate-Demate Devices, large gantry-like structures that hoist the orbiters off the ground for post-flight servicing, and then mate them with the SCAs for ferry flights.

In approach and landing test flights conducted in 1977, a test shuttle was released from an SCA during flight and glided to a landing under its own control.[1]

Contents

Design and development

The first aircraft, a Boeing 747-100 registered N905NA, was originally manufactured for American Airlines and still carried visible American side stripes while testing Enterprise in the 1970s. It was acquired in 1974 and initially used for trailing wake vortex research as part of a broader study by NASA Dryden, as well as Shuttle tests involving an F-104 flying in close formation and simulating a "release" from the 747.

Shuttle Carrier Aircraft N905NA, in American Airlines livery, with Enterprise in 1978.

The aircraft was extensively modified by Boeing in 1976.[2] Its cabin was stripped, mounting struts added, and the fuselage strengthened; vertical stabilizers were added to the tail to aid stability when the Orbiter was being carried. The avionics and engines were also upgraded, and an escape tunnel system similar to that used on Boeing's first 747 test flights was added. The flight crew escape tunnel system was later removed following the completion of the Approach and Landing Tests (ALT) due to concerns over possible engine ingestion of an escaping crew member.

The Lockheed C-5 Galaxy was considered for the shuttle-carrier role by NASA, but rejected in favor of the 747—in part due to the 747's low-wing design in comparison to the C-5's high-wing design, and also because the U.S. Air Force would have retained ownership of the C-5, while NASA could own the 747s outright.

Atlantis being mated to SCA N911NA at Dryden Flight Research Center

Flying with the additional drag and weight of the Orbiter imposes significant fuel and altitude penalties. The range is reduced to 1,000 nautical miles (1,850 km), compared to an unladen range of 5500 nautical miles (10,100 km),[3] requiring an SCA to stop several times to refuel on a transcontinental flight. The SCA has an altitude ceiling of 15,000 feet and a maximum cruise speed of Mach 0.6 with the orbiter attached.[3] A crew of 170 takes a week to prepare the shuttle and SCA for flight.[4]

Columbia atop SCA N905NA, flying by the Vehicle Assembly Building (VAB) at Kennedy Space Center (KSC), 1990. N905NA no longer has American Airlines' pinstriping.

Studies were conducted to equip the SCA with aerial refueling equipment, a modification already made to the U.S. Air Force E-4 (modified 747-200s) and 747 tanker transports for the IIAF. However, during formation flying with a tanker aircraft to test refueling approaches, minor cracks were spotted on the tailfin of N905NA. While these were not likely caused by the test flights, it was felt that there was no sense taking unnecessary risks. Since there was no urgent need to provide an aerial refueling capacity, the tests were suspended.

By 1983, SCA N905NA no longer bore the distinct American Airlines red, white, and blue cheatline. NASA replaced it with its own livery, consisting of a white fuselage and a single blue cheatline.[5] That year, this aircraft was also used to fly Enterprise on a tour in Europe, with refuelling stops in Goose Bay, Canada, Keflavik, Iceland, England and West Germany. It then went to the Paris Air Show.[6]

In 1988, in the wake of the Challenger accident, NASA procured a surplus 747-100SR from Japan Airlines. Registered N911NA it entered service with NASA in 1990 after undergoing modifications similar to N905NA. It was first used in 1991 to ferry the new shuttle Endeavour from the manufacturers in Palmdale, California to Kennedy Space Center.

Humorous note on Orbiter Mount reminding technicians how to connect the orbiter to the transport.

The two aircraft are functionally identical, although N911NA has five upper-deck windows on each side, while N905NA has only two. The rear mounting points on both aircraft are labeled with similar tongue-in-cheek instructions to "Attach Orbiter Here" or "Place Orbiter Here", clarified by the precautionary note "Black Side Down".[7][8] Both are currently based at the Dryden Flight Research Center within Edwards Air Force Base in California.

Shuttle Carriers are capable of operating from alternate shuttle landing sites such as those in the United Kingdom, Spain and France. Due to the reduced range of the Shuttle Carrier while mated to an orbiter, additional preparations such as removal of the payload from the orbiter may be necessary to reduce its weight.[9]

Boeing transported its Phantom Ray unmanned combat air vehicle (UCAV) demonstrator from St. Louis, Missouri, to Edwards AFB, California, on a Shuttle Carrier on December 11, 2010.[10]

After the Shuttle program ends in 2011, the two Shuttle Carriers will be used to transport the orbiters to their final destinations. The carrier aircraft will likely retire sometime afterwards.[citation needed]

Specifications

SCA 3-view schematic

Data from Boeing 747-100 specifications[11] Jenkins 2000[3]

General characteristics

  • Crew: 4: pilot, co-pilot, 2 flight engineers (1 flight engineer when not carrying Shuttle)
  • Length: 231 ft 4 in (70.5 m)
  • Wingspan: 195 ft 8 in (59.7 m)
  • Height: 63 ft 5 in (19.3 m)
  • Wing area: 5,500 ft² (510 m²)
  • Empty weight: 318,000 lb (144,200 kg)
  • Max takeoff weight: 710,000 lb (322,000 kg)
  • Powerplant: 4 × P&W JT9D-7J turbofans, 50,000 lbf (222 kN) each

Performance

  • Cruise speed: Mach 0.6 (397 knots, 457 mph, 735 km/h)
  • Range: 1,150 mi (1,000 nmi, 1,850 km) while carrying Shuttle
  • Service ceiling: 15,000 ft (4,500 m) (with Shuttle)

Gallery

See also

Related development
Aircraft of comparable role, configuration and era

Related lists

References

  1. ^ NASA - Dryden Flight Research Center (1977). "Shuttle Enterprise Free Flight". NASA. http://grin.hq.nasa.gov/ABSTRACTS/GPN-2000-000218.html. Retrieved November 28, 2007. 
  2. ^ Jenkins 2000, pp. 36-38.
  3. ^ a b c Jenkins 2000, pp. 38-39.
  4. ^ Felix Gilette (9 August 2005). "How Does the Space Shuttle Fly Home?". http://www.slate.com/id/2124238/fr/rss/. Retrieved 2007-11-23. 
  5. ^ Comparison of photos taken in 1982 and 1983 at Airliners.net
  6. ^ http://www.slate.com/id/2124238/
  7. ^ 2003 Edwards Air Force Base Air Show, see Shuttle Carrier images.
  8. ^ Shuttle Carrier Aircraft N911NA album on Photobucket
  9. ^ "Space Shuttle Transoceanic Abort Landing (TAL) Sites". National Aeronautics and Space Administration. December 2006. http://www.nasa.gov/centers/kennedy/pdf/167472main_TALsites-06.pdf. Retrieved 2009-07-01. 
  10. ^ Boeing Phantom Ray to catch shuttle ride at Lambert
  11. ^ Boeing 747-200 Technical Specifications, Boeing

Bibliography

  • Jenkins, Dennis R. Boeing 747-100/200/300/SP (AirlinerTech Series, Vol. 6). Specialty Press, 2000. ISBN 1580070264.
  • Jenkins, Dennis R. Space Shuttle: The History of the National Space Transportation System - The First 100 Missions, 3rd edition. Midland Publishing, 2001. ISBN 0963397451.

External links


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