New England Air Museum
Curtiss D-12



The D-12 was a 12-cylinder, water-cooled, V-type engine that was introduced in 1921. It became a successful and popular engine of the 1920's in military aircraft and Curtiss racing airplanes because of its relatively low frontal area. Arthur Nutt designed the D-12 as an improvement to the earlier Curtiss K-12. The engine has cast cylinder blocks for each bank of 6 cylinders and 4 valves per cylinder. The power output was about 400 hp at 2,000 rpm.

When it powered the Fairey Fox in 1925, the fastest airplane in England, it inspired Rolls-Royce to develop its famous Merlin engine. It was used in mail planes until the Pratt & Whitney 9-cylinder, air-cooled Wasp engine came along.

This example was manufactured in 1921. The D-12 was a great step forward in liquid-cooled engines and influenced inline military and racing engines through the start of World War II.

This engine is located in the connector between the Military and Civilian hangars.

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Type: 12-cylinder, water-cooled, "V" piston engine
Displacement: 1,145 cu. in.
Weight: 693 lbs.
Power Output: 400 hp at 2,000 rpm
Compression Ratio: 6:1
NEAM Id: 67


Engine Collection Index