Continental built this engine under license from Wright. It is a member of the Wright J-6 Whirlwind family, which was sometimes referred to as the J-6-9. The well known designers Sam Heron, and Charles Lawrance were involved during the mid-1920s with the original version of the J-6, which produced up to 336 kW (450 hp).
During World War II, the further developed Continental engine was installed in medium tanks. Following the war, the R-975 (an improved J-6) was used in Piasecki and Kaman helicopters for the Army, Navy and Air Force.
This artifact was a spare engine for the museum’s XV-1 Convertiplane, a mid-1950s USAF and McDonnell joint development using a jet-driven motor for vertical flight and standard pusher propeller for forward flight. Because it was submerged within the fuselage, the R-975 was equipped with a cooling fan. By 1961, conventional helicopters achieved the same flight speed as the Convertiplane, thus dooming this particular concept.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.