The Pregnant Guppy is a modified Boeing B-377 Stratocruiser used to transport the S-IV (second) stage for the Saturn I launch vehicle between manufacturing facilities on the West coast, and testing and launch facilities in the Southeast. The fuselage of the B-377 was lengthened to accommodate the S-IV stage and the plane's cabin section was enlarged to approximately double its normal volume. The idea was originated by John M. Conroy of Aero Spaceliners, Incorporated, in Van Nuys, California. The former Stratocruiser became a B-377 PG: the Pregnant Guppy. This photograph depicts the Pregnant Guppy in flight.
NASA
1960
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