Boeing 377

The Boeing 377 Stratocruiser was a large long-range airliner developed from the C-97 Stratofreighter military transport, a derivative of the B-29 Superfortress. The Stratocruiser's first flight was on July 8, 1947. Its design was advanced for its day, its innovative features included two passenger decks and a pressurized cabin, a relatively new feature to transport aircraft. It could carry up to 100 passengers on main deck plus 14 in lower deck lounge; typical seating was for 63 or 84 passengers or 28 berthed and five seated passengers. The Stratocruiser was larger than the Douglas DC-6 and Lockheed Constellation and cost more to buy and operate. Its reliability was poor, chiefly due to problems with the four 28-cylinder Pratt & Whitney Wasp Major radial engines and their four-blade propellers. Only 55 Model 377s were built for airlines, along with the single prototype.