Aero Spacelines developed the turboprop conversion on the 377MGT first, then used the same conversion on the more successful Super Guppys.
The 1970 Guppy-101 was from a rebuilt from Boeing Stratocruiser with four 4900hp Allison 501-D22C turboprops. It was the first with the opening nose section.
The 377MGT Mini Guppy Turbine, first flew on March 13, 1970, but was involved in an accident at Edwards Air Force Base on May 12, 1970. With the crash of the 377MGT and the shrinking budgets, Aero Spacelines found itself no customers for the 377MGT.
Guppy-101
Engine: 4 x Allison 501-D22C turboprops, 3510kW
Take-Off Weight: 81500 kg / 179678 lb
Empty Weight: 41270 kg / 90985 lb
Payload: 28500kg / 62832 lb
Wingspan: 47.6 m / 156 ft 2 in
Length: 41.3 m / 135 ft 6 in
All Aero 