It first flew on July 8, 1947.
Despite serious design flaws and a marginal service record, the Boeing 377 Stratocruiser was one of the great post-war propeller airliners.
Because it was very complex and expensive, only 56 aircraft were built.
It was made obsolete in the 1960 by the coming of the Boeing 707 and other first generation jetliners. The Boeing 377 was the flagship of the Pan American World Airways and BOAC fleets from delivery in 1949 until the arrival of the Boeing 707. Its spiral staircase, which led to a lower-deck lounge, inspired the one on the Boeing 747. It was one of the few airliners with a double-decker seating arrangement until the Boeing 747, however some airlines had lower-level lounges on their Lockheed L-1011 Tristar aircraft. General characteristics