This was among the largest piston engines ever successfully produced. Design began in early-1936, and the first engine ran in mid-1937. Development and early application was particularly troubled by catastrophic backfires. The major airframe application of the Wright R-3350 engine was during World War II on the Boeing B-29.
The engine continued to give useful service after the war, one version of which was the first of its type to have its exhaust turbines (3 of them) geared into the power system. Called the Wright Turbo-Compound Cyclone, it was the last and the most highly developed piston engine to be widely used in large military and commercial airplanes. Airline application was in the Douglas DC-7 and Lockheed Super Constellation.
Only two R-3350-14 engines were built, and those were for the Douglas XSB2D-1 and B2D-1.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.