The Boeing 377 Stratocruiser was the civilian version of the C-97 transport, itself an adaptation of the B-50 bomber, which in turn was an adaptation of the B-29 bomber. With its four R-4360 engines, unique double lobed, double decked fuselage and pressurized cabin, it was the epitome of piston engine airliner luxury.
It was also something of a disaster. It was extremely expensive to operate compared to its competition, and had a rather ghastly habit of crashing. Of 56 hulls built, 13 were lost in less that 20 years.
Pan American Flight 943 lands in the Pacific on Oct. 16, 1956. The Boeing 377 Stratocruiser had lost power to two of its four engines and had to risk an emergency water landing. (William Simpson / US Coast Guard)
On the other hand, some airframes, heavily modified, went on to become the iconic Super Guppy family of outsized cargo transports.