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:
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.