Kaman K-225 “Mixmaster”
The K-125 was Charles Kaman’s first helicopter, which utilized intermeshing rotors and Kaman’s patented servo-flap stability control. The K-125 first flew on 15 January 1947.The K-190 and K-225 were an improved versions of the K-125, which first flew in April and July 1949 respectively. The U.S. Navy bought two K-225s and the Coast Guard one to test and evaluate. The cost was $25,000 each. The United States Air Force evaluated one K-225 with the designation YH-22.
On 11 May 1950, CG-239 went into the workshops at Elizabeth City after undergoing 120 flying hours of testing and evaluation.. After this, it was apparently “little used” except for pilot refresher training. CG-239 was transferred to the Navy on 22 March 1954 and was later sold into private hands.
Kaman later modified the K-225 installing a turboshaft engine. It was the world’s first gas turbine- powered helicopter. This aircraft is now at the Smithsonian Institution in Washington, D.C.