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Curtiss D-12

DAYTON, Ohio -- Curtiss D-12 engine at the National Museum of the United States Air Force. (U.S. Air Force photo)

DAYTON, Ohio -- Curtiss D-12 engine at the National Museum of the United States Air Force. (U.S. Air Force photo)

The 375-hp Curtiss D-12 engine, introduced in 1921, became one of the most successful aircraft engines of the 1920s. Developed from Curtiss' K-12 engine used in World War I, the D-12 replaced the gears connecting the crankshaft to the propeller with a more reliable direct-drive connection, hence the "D" for direct-drive. Also, Curtiss attached a new propeller designed by acoustics engineer Dr. S.A. Reed. It could rotate at a higher speed than conventional propellers, allowing the engine to use its full power. This combination made the D-12 the most advanced power plant in the world.

After powering the famous series of Curtiss racers to numerous victories in the early 1920s, the D-12 influenced inline military and racing engines through the start of World War II. The Army installed them in such fighter aircraft as the Curtiss PW-8 and Boeing PW-9.

Type: Liquid-cooled, V-12
Displacement: 1,145 cu.in.
Maximum hp: 375 (435 in later models)
Maximum rpm: 2,000 (2,300 in later models)

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Mask Policy:
In accordance with the updated guidance released by the Center for Disease Control and Prevention (CDC), the Department of Defense (DoD) and Wright-Patterson Air Force Base, the National Museum of the U.S. Air Force will require all visitors to wear face masks indoors effective July 30, 2021 until further notice.

Visitors ages three and up will be required to wear masks while indoors at the museum. This policy applies to all visitors, staff and volunteers regardless of vaccination status. Visitors may wear their own masks or a free paper mask will be provided. Cloth masks will also be available for purchase in the Museum Store.
Additional information available here.

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