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Curtiss K-12

Note: This item is currently in storage.

The Curtiss K-12 was a milestone in the development of liquid-cooled aircraft engines and was regarded as one of the most advanced in the world for its time. Designed by Charles B. Kirkham and first tested in 1916, the K-12 featured a cast aluminum upper crankcase and integral cylinder blocks, four valves per cylinder, and "wet sleeve" construction for improved cooling. It relied upon high rpm and reduction gearing to develop the same power as larger engines. Although technologically advanced, many of the K-12's innovations challenged the state-of-the-art and created serious reliability problems. The K-12 design, however, led to the development of the very successful Curtiss D-12 (1922) engine used in fighters and racing planes. By 1926 the D-12 design had evolved into the more powerful Curtiss V-1570 Conqueror, noted for its use in military aircraft. That evolution was continued in the powerful liquid-cooled, V-12 aircraft engines of World War II that owed so much to design concepts pioneered in the K-12 engine of 1916.

Type: 12-cylinder, liquid-cooled, Vee
Displacement: 1,145
Rated hp: 375
Rated rpm: 2,250

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Related Fact Sheets
Curtiss D-12 Engine
Curtiss V-1570 Conqueror Engine
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