being loaded aboard a Super Guppy at Ellington AFB, August 1969 The first Super Guppy, or "SG", was built directly from a retired USAF
Boeing YC-97J Stratofreighter. The fuselage was lengthened to , and ballooned out to a maximum inside diameter of , the length of the cargo compartment being . The floor of the cargo compartment was still only wide, as necessitated by the use of the Stratocruiser fuselage. in 1981 The second version was officially known as the Super Guppy Turbine (SGT), although the first Super Guppy also used turboprop engines. However, this variant used
Allison 501-D22C engines. Unlike the previous Guppy, the main portion of its fuselage was constructed from scratch. By building from scratch, Aero Spacelines was able to widen the floor of the cargo compartment to . The overall cargo-compartment length was increased to , and the improved fuselage and engines allowed for a maximum load of . 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 nose gear was taken from a
Boeing 707 and rotated 180 degrees. This dropped the front of the aircraft slightly, levelling the cargo-bay floor and simplifying loading operations. In the early 1970s, two SGT aircraft were used by
Airbus to transport airplane parts from production facilities to the final assembly plant in
Toulouse. In 1982 and 1983, two additional Super Guppy Turbines were built by
Union de Transports Aériens Industries in France after Airbus bought the right to produce the aircraft. The four Super Guppies were later replaced in this role by the
Airbus Beluga, capable of carrying twice as much cargo by weight. ==Variants==