The 377MG Mini-Guppy was the first of the new generation of Guppys that was built using an entirely new fuselage to connect the existing Stratocruiser sections. Gone was the modified Stratocruiser's limitation of a 2.4m wide floor. By designing a new fuselage, Aero Spacelines was able to create the first "wide-body" Guppy, with a 4m wide cargo floor and a maximum inside diameter of 5.5m with the constant section measuring just over 22m long.
The first flight as 377MG Mini-Guppy, christened "Spirit of Santa Barbara", was on May 24, 1967. This Guppy featured a swing tail for loading cargo.
Only two days later on May 26, the Mini-Guppy was used for it's first cargo flight, flying a Budd Company Skylounge across the Atlantic to the 1967 Paris Airshow. While in France, the Mini-Guppy was flown south to Toulouse for a demonstration for Aerospatiale officials who were considering using this type of an aircraft in the future production of planned airliners.
