Pratt & Whitney R-1690 Hornet
9-cylinder radial engine family by Pratt & Whitney
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.
Variants
R-1690-3
525 hp (391 kW)
R-1690-5
525 hp (391 kW)
R-1690-11
775 hp (578 kW)
R-1690-13
625 hp (466 kW)
R-1690-S5D1G
700 hp (520 kW)
R-1690-52
750 hp (560 kW)
R-1690-SDG
R-1690-S1EG
750 hp (560 kW)
R-1690-S2EG
R-1690-25
850 hp (630 kW)
R-1690-S1C3G
1,050 hp (780 kW)
Fiat A.59 R.
License built in Italy with reduction gearing.
Fiat A.59 R.C.
License built in Italy with reduction gearing and supercharger.
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