Design and development
The first, the Super Guppy, or “SG”, was built directly from the fuselage of a C-97J Turbo Stratocruiser, the military version of the Boeing 377. The fuselage was lengthened to 141 feet (43 m), and ballooned out to a maximum inside diameter of 25 ft (7.6 m), the length of the cargo compartment being 94 ft 6 in (28.8 m). The floor of the cargo compartment was still only 8 ft 9 in (2.7 m) wide, as necessitated by the use of the Stratocruiser fuselage.
In addition to the fuselage modifications, the Super Guppy used upgraded Pratt & Whitney T-34-P-7 turboprops for increased power and range, and modified wing and tail surfaces. It could carry a load of 40,000 pounds (18,000 kg) and cruise at 300 mph (480 km/h).
The second version was officially known as the Super Guppy Turbine (SGT) because the original 377 engines had been replaced with high-performance Allison 501-D22C turboprops. Unlike previous Guppies, the fuselage was constructed from scratch. By building from scratch, Aero Spacelines was able to widen the floor of the cargo compartment to 13 ft (4 m). The overall cargo compartment length was increased to 111 ft (33.8 m), and the improved fuselage and engines allowed for a maximum load of 54,500 pounds (24,700 kg). These design improvements, combined with a pressurized crew cabin that allowed for higher-altitude cruising, allowed the SGT to transport more cargo than its predecessors.
The SGT retained only the cockpit, wings, tail, and main landing gear of the 377. The nosegear was taken from the Boeing 707 — and reversed 180 degrees. This dropped the front of the aircraft slightly, leveling the cargo bay floor and simplifying loading operations.
In the early 1970s, the two Super Guppies were used by Airbus Industrie to transport aeroplane parts from decentralised production facilities to the final assembly plant in Toulouse. The running joke was “Every Airbus is delivered on the wings of a Boeing”. In 1982 and 1983 two additional Super Guppies were built by UTA Industries in France after Airbus bought the right to produce the aircraft. The four Super Guppies have since been replaced by the Airbus Beluga, capable of carrying twice as much cargo.
The last produced Super Guppy remains in service: an SGT flown by NASA (currently used to ferry components for the International Space Station and Project Orion). The other four are mothballed; the SG at Pima Air and Space Museum, Davis-Monthan Air Force Base, Arizona, United States, the first SGT, which has recently begun a restoration project, at Bruntingthorpe, United Kingdom, the second outside Airbus’ factories at Blagnac Airport, Toulouse, France, and the third at Finkenwerder, Germany.
- Aero Spacelines B-377-SG Super Guppy – Prototype of a much enlarged version of the guppy using C-97J components, powered by four Pratt & Whitney T-34-P-7WA turbo-prop engines.
- Aero-Spacelines B-377-SGT Super Guppy Turbine – Production version powered by Allison 501-D22C turbo-prop engines, using an enlarged cargo section built from scratch instead of being converted from original C-97J components.
- Aero Spacelines Guppy-210 – alternative designation for production SGT’s.
Specifications (Super Guppy)
- Crew: Four
- Length: 143 ft 10 in (43.84 m)
- Wingspan: 156 ft 3 in (47.625 m)
- Height: 46 ft 5 in (14.148 m)
- Empty weight: 101,500 lb (46,039 kg)
- Useful load: 54,500 lb (24,720 kg)
- Max takeoff weight: 170,000 lb (77,110 kg)
- Powerplant: 4× Allison 501-D22C turboprops, 4,680 hp (3,491 kW) each
- * Cargo bay dimensions: 111 ft x 25 ft x 25 ft (33.8 m x 7.62 m x 7.62 m)
- Cruise speed: 252 knots (288 mph, 467 km/h)
- Range: 1,734 nm (1,986 mi, 3,219 km)
- Service ceiling: 32,000 ft (9,753.6 m)