New England Air Museum
Pratt & Whitney R-1690 Hornet



The Hornet series of Pratt & Whitney engines began development in 1926 and was the second major line following the Wasp. The U.S. Navy looked to the Hornet as a replacement for the heavy Packard engines in its torpedo and bomber aircraft. The results were so good that the Navy ceased buying water-cooled engines. The engine was produced until 1942 with 2,944 units built.

The Hornet is most closely associated with Sikorsky flying boats as it powered the S-40, S-42 and S-43. It also powered the prototype of the Boeing B-17 the Model 299. Other aircraft to utilize the R-1690 included:

  • Boeing 80A, Model 95, Model 221
  • Burnelli UB-14B
  • Douglas O-38
  • Fokker F.32
  • Junkers Ju 52 protoype
  • Lockheed Model 14 Super Electra

An enlarged version the Hornet B was produced from 1929 but was not a commercial success as it competed with the cheaper and simpler Twin Wasp.

The engine is located in the Civilian Hangar near the DC-3.

If you have any information, comments on, or recollections of the R-1690, please contact This e-mail address is being protected from spambots. You need JavaScript enabled to view it. .



Type: 9-cylinder, single-row, air-cooled, radial
Displacement: 1,690 cu. in.
Dry Weight: 1,014 lbs.
Power Output: 525 to 875 depending on model
NEAM Id: 79


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