August 1962, while on an intermediate stop during a ferry flight to Moscow for acceptance testing, Ka-22 01-01 rolled to the left and crashed inverted, killing the entire crew. The cause was found to be the starboard rotor collective pitch control linkage, and further inspection found that two of the other three Ka-22s suffered from similar problems. Subsequently, in order to improve stability and control, a complex differential autopilot was installed. This sensed attitude and angular accelerations, and fed into the control system. On 12 August 1964, while involved in Soviet Air Force testing, 01-03 was destroyed. The aircraft entered an uncontrolled turn to the right, and in efforts to correct the Ka-22 pitched into a steep dive. The order was given to abandon the aircraft, and three of the crew survived, but Col S.G. Brovtsev, who was flying, and technician A.F. Rogov, were killed. After this, the Ka-22 was abandoned, with the Mil Mi-6 having already taken on the heavy helicopter role. Eventually the two surviving machines, 01-02 and 01-04, were scrapped. The Ka-22 was only seen once by western observers during the Cold War during an Aviation Day display in Moscow on 9 July 1961. Specifications (Ka-22) See also References Notes Bibliography Apostolo, Giorgio. The Illustrated Encyclopedia of Helicopters. New York: Bonanza Books, 1984. . Kamov aircraft Gyrodynes 1950s Soviet military transport aircraft Transverse rotor helicopters High-wing aircraft Turboshaft-powered aircraft Aircraft first flown in 1959 Twin-turboprop tractor aircraft