The BMW 132 was a nine-cylinder radial aircraft engine produced by BMW starting in 1933.
BMW 132
BMW 132 engine
Connecting rods
BMW 132, M15 in the National Military Museum, Romania.
Pratt & Whitney R-1690 Hornet
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. 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.
Pratt & Whitney R-1690 Hornet
R-1690 with chamber walls cut away to show internal workings