Pratt & Whitney R-1690 Hornet

R-1690 Hornet
Pratt & Whitney Hornet, at the Deutsches Museum, Munich.
Type Radial engine
National origin United States
Manufacturer Pratt & Whitney
First run June 1926
Major applications Boeing 80
Lockheed Lodestar
Sikorsky S-42
Vought O2U Corsair
Number built 2,944
Developed into Pratt & Whitney R-1860
BMW 132
Mitsubishi Kinsei

The Pratt & Whitney R-1690 Hornet was a widely used American aircraft engine. Developed by Pratt & Whitney, 2,944 were produced from 1926 through 1942. It first flew in 1927. It was a single-row, 9-cylinder air-cooled radial design. Displacement was 1,690 cubic inches (27.7 L). It was built under license in Italy as the Fiat A.59. In Germany, the BMW 132 was a developed version of this engine. The R-1860 Hornet B was an enlarged version produced from 1929.