The Pratt & Whitney R-1690 Hornet was a widely used 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 licence 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.
R-1690-3525 hp (392 kW)
R-1690-5525 hp (392 kW)
R-1690-11775 hp (578 kW)
R-1690-13625 hp (466 kW)
R-1690-S5D1G700 hp (522 kW)
R-1690-52750 hp (559 kW)
R-1690-SDGR-1690-S1EG750 hp (559 kW)
R-1690-S2EGR-1690-25850 hp (634 kW)
R-1690-S1C3G1,050 hp (780 kW)
Fiat A.59 R.Licence built in Italy with reduction gearing.
Fiat A.59 R.C.Licence built in Italy with reduction gearing and supercharger.
BMW HornetLicence production of the Hornet in Germany, independently developed as the
BMW 132.
Bach Air YachtBellanca 31-40Boeing 80Boeing Model 95Boeing Model 299Burnelli UB-14Douglas O-38Focke-Wulf Fw 200 V1Junkers Ju-52Junkers Ju 86Junkers W 34Keystone B-3Lockheed Model 14 Super Electra (L-14H)Lockheed Lodestar (C-56A, C-56B, C-56C, C-56D, C-56E, C-59/Mk 1a)Martin XB-14Vought O2U CorsairSikorsky S-40ASikorsky S-42Sikorsky S-43Wedell-Williams Model 44There is a R-1690 on display at the New England Air Museum, Bradley International Airport, Windsor Locks, CT.Data from
Type: Nine-cylinder single-row supercharged air-cooled radial engineBore: 6 1⁄8 in (155.6 mm)Stroke: 6 3⁄8 in (161.9 mm)Displacement: 1,690.5 in³ (27.7 l)Length: 50.98 in (1,295 mm)Diameter: 54.41 in (1,382 mm)Dry weight: 1,014 lb (460 kg)Valvetrain: Pushrod-actuatedSupercharger: Single-speed centrifugal type supercharger, 12.0:1 gear ratioFuel system: Two-barrel Stromberg carburetorFuel type: 87 octane rating gasolineCooling system: Air-cooledReduction gear: Epicyclic gearing, 2:3Power output:
789 hp (589 kW) at 2,300 rpm for takeoff740 hp (552 kW) at 2,250 rpm at 7,000 ft (2,135 m)Specific power: 0.47 hp/in³ (21.26 kW/l)Compression ratio: 6.0:1Specific fuel consumption: 0.6 lb/(hp•h) (362 g/(kW•h))Oil consumption: 0.42 oz/(hp•h) (16 g/(kW•h))Power-to-weight ratio: 0.78 hp/lb (1.28 kW/kg)