AKA: 747. Status: Out of Production. Payload: 109,000 kg (240,000 lb). Thrust: 835.23 kN (187,767 lbf). Gross mass: 276,364 kg (609,278 lb). Unfuelled mass: 177,000 kg (390,000 lb). Specific impulse: 10,939 s. Specific impulse sea level: 9,944 s. Burn time: 3,825 s. Height: 70.70 m (231.90 ft). Diameter: 19.26 m (63.18 ft). Span: 59.66 m (195.73 ft). Location: 150.
NASA used two modified Boeing 747 jetliners, originally manufactured for commercial use, as Space Shuttle Carrier Aircraft (SCA). One was a 747-100 model, while the other was a 747-100SR (short range). The two aircraft were identical in appearance and in their performance as Shuttle Carrier Aircraft.
The 747 series of aircraft were four-engine intercontinental-range, swept-wing "jumbo jets" that entered commercial service in 1969.
The SCAs were used to ferry space shuttle orbiters from landing sites back to the launch complex at the Kennedy Space Center and also to and from other locations too distant for the orbiters to be delivered by ground transportation.
The orbiters were placed atop the SCAs by Mate-Demate Devices, large gantry-like structures that hoisted the orbiters off the ground for post-flight servicing, and then mated them with the SCAs for ferry flights.
Features which distinguished the two SCAs from standard 747 jetliners were:
· Three struts with associated interior structural strengthening protruded from the top of the fuselage (two aft, one forward) on which the orbiter was attached.
· Two additional vertical stabilizers, one on each end of the standard horizontal stabilizer, to enhance directional stability.
· Removal of all interior furnishings and equipment aft of the forward No. 1 doors.
· Instrumentation used by SCA flight crews and engineers to monitor orbiter electrical loads during the ferry flights and also during pre- and post-ferry flight operations.
The two SCAs were under the operational control of NASA's Johnson Space Center, Houston, TX.
NASA 905
NASA 905 was the first SCA. It was obtained from American Airlines in 1974. Shortly after it was accepted by NASA it was flown in a series of wake vortex research flights at the Dryden Flight Research Center in a study to seek ways of reducing turbulence produced by large aircraft. Pilots flying as much as several miles behind large aircraft have encountered wake turbulence that have caused control problems. The NASA study helped the Federal Aviation Administration modify flight procedures for commercial aircraft during airport approaches and departures.
Following the wake vortex studies, NASA 905 was modified by Boeing to its SCA configuration and the aircraft was returned to Dryden for its role in the 1977 Space Shuttle Approach and Landing Tests (ALT). This series of eight captive and five free flights with the orbiter prototype Enterprise, in addition to ground taxi tests, validated the aircraft's performance as an SCA, in addition to verifying the glide and landing characteristics of the orbiter configuration paving the way for orbital flights.
A flight crew escape system, consisting of an exit tunnel extending from the flight deck to a hatch in the bottom of the fuselage, was installed during the modifications. The system also included a pyrotechnic system to activate the hatch release and cabin window release mechanisms. The flight crew escape system was removed from the NASA 905 following the successful completion of the ALT program.
NASA 905 was the only SCA used by the space shuttle program until Nov. 1990, when NASA 911 was delivered as an SCA. Along with ferrying Enterprise and the flight rated orbiters between the launch and landing sites and other locations, NASA 905 also ferried Enterprise to Europe for display in England and at the Paris Air Show.
NASA 911
The second SCA was designated NASA 911. It was obtained by NASA from Japan Airlines (JAL) in 1989. It was also modified by Boeing Corporation. It was delivered to NASA Nov. 20, 1990.
SCA Descriptions
Dimensions
Wingspan: 195 ft. 8 in.
Length: 231 ft. 10 in.
Height: Top of vertical stabilizer, 63 ft. 5 in.; To top of cockpit area, 32 ft. 1 in.
Weight: Basic weight, NASA 905, 318,053 lbs- NASA 911, 323,034 lbs; Maximum gross taxi weight, 713,000 lbs; maximum gross brake release weight, 710,000 lbs; maximum gross landing weight, 600,000 lbs
Engines
Four Pratt and Whitney JT9D-7J gas turbine engines, each producing 50,000 lbs of thrust
Performance
Airspeed limits with, and without an orbiter: 250 knots or Mach 0.6
Altitude: Typical cruise with orbiter, 13,000-15,000 ft MSL; typical cruise unmated, 24,000-26,000 ft MSL. Minimum temperature at altitude 15 degrees (F) (-9 degrees C) or 8 psi ambient pressure
Range : Typical mated, 1000 nautical miles (with reserves); maximum unmated, 5500 nautical miles
Fuel Capacity
47,210 gallons (316,307 lbs) jet fuel
Crew
Minimum for flight was two pilots and one flight engineer. Minimum for mated flight was two pilots and two flight engineers.
Cost $ : 100.000 million. No Engines: 4. Release velocity: 150 m/s (490 ft/sec). Release conditions: 538 kph at 5.2 km.