VTOL - Vertical Takeoff and Landing Aircraft
The Soviet VTOL/STOVL aircraft program was a complete failure. The postwar period of development of Soviet aircraft production was marked by a scientific and technical revolution - the beginning era of jet aircraft. The creation of a powerful jet aircraft fleet and complete changeover to military jets and the civil air fleet was a new test for Soviet aviators and the aircraft industry.
The problem of vertical take-off and landing had for a long time challenged the skill of aircraft engineers all over the world. There are various principles which enable aircraft to take off from confined spaces, but only a fewe of these projects had been actually realized.Such aircraft are notoriously difficult to develop, and the British Aerospace Sea Harrier remains the only effective VTOL/STOVL aircraft to date. The possibility of building such aircraft was given by the advent of sufficiently powerful and light turbojet engines. Vertical take-off requires that the thrust of the engine exceed the weight of the aircraft. In the Soviet plane the jet stream of the engine is deflected downward by special swiveling nozzles, thus directing the thrust into a vertical direction. When the aircraft has reached a sufficient altitude, the pilot gradually turns the nozzle into a horizontal position, thus changing the direction of the exhaust gas stream and accelerating.
One stream of Soviet VSTOL development consisted of the competitive evaluation of the performance of VSTOL and swing wing fighter aircraft for short airfield operations. One of the first indications of a new agenda for the Soviet Air Forces was the Domodedovo Air Show of 9 July 1967, a real shocker. Writing in his autobiography Fifty Years Of Soviet Aircraft Construction (50 let sovetskogo samolet ostroeniya], chief designer and aviation pioneer A.S. Yakovlev noted "The five years since 1961 are marked by further outstanding achievements of Soviet aircraft construction. At the 23rd Party Congress the Minister of Defense spoke of the new and modern planes supplied to the air force. He especially pointed out that new and highly efficient complexes of interceptor planes had been created and supplied to the forces; qualitative changes had been made in long-range aviation; a considerable part of tactical, sea, rocket-carrying, and especially of military transport planes had been replaced by more modern models. The air display in Domodedovo on 9 July 1967 was convincing evidence of this rapid progress. It was a demonstration of the quality that Soviet aviation had achieved on the 50th anniversary of Soviet power. The program of the display proved that aviation science and practice in the USSR had achieved new successes in the six years since 1961. Planes which in 1961 had been shown only as prototypes flew in entire squadrons, piloted by rank-and-file military airmen." [page 107]
Although the Soviets had not mounted an air show or Aviation Day for six years, in July 1967, at the new Domodedovo Civil Airport south of Moscow, the Soviets surprised the world by unveiling 12 new and advanced military aircraft. The Soviets unveiled a new generation of aircraft that reflected a renewed commitment to frontal aviation and combined arms doctrine. On that Day of the Air Fleet, the Soviets displayed a new generation of fighters with variable geometry wings, vertical takeoff and landing aircraft (VTOL), and short takeoff and landing aircraft (STOL). The Sukhoi T-6 experimental attack aircraft was very similar to the Su-24 in outline, but had four lift engines for STOL performance, and fixed swept wings. Due to an accident, it missed Domodedovo. Later T-6's had swing wings and were closer to the Su-24. Unkown to the West at the time, the VTOL and STOL prototypes had lost the competition, and the variable geometry fighters went into series production.
The second, somewhat more successful VTOL program was undertaken by the Yakovlev design bureau, and was associated with the project for building heavy air-capable cruisers (Russian acronym TAVKR) was supported by Dmitry Ustinov, secretary of the Soviet Communist Party's Central Committee in 1965-1976 with oversight of the armed forces, the defense industry and security agencies. TAVKR was an unviable hybrid warship combining the specifications of a heavy cruiser and an aircraft carrier. The government decision to build TAVKRs also heralded the beginning of a program to develop VTOL/STOVL (Vertical Take-Off and Landing/Short Take-Off and Vertical Landing) aircraft. This was an ambitious task.
V. Mukhin flew the first Soviet VTOL jet plane shown in 1967, the Yak-36 Freehand. This aircraft, powered by two turbojet engines with swiveling nozzles and with a system of jet control, does not need any concrete runway; it can take off and land on the tiniest patch. The combination of high speed and this unique take-off and landing performance offers aircraft completely new potentialities. It is of interest to note that in spite of a long, successful, trouble-free, flight operational history (over 25 yr), the cascade-vector principle used on the X-14 has not been used in any subsequent designs; however, the Russian experimental YAK-36 ("Free-hand") used a similar VTOL principle.
The Soviet Yak-38 "Forger" single-seat naval fighter was similar to the Harrier. It operated from the USSR's four multipurpose cruiser/aircraft carriers during the 1970s and 1980s. Test examples of the VTOL Yak-36 (Forger) were operated aboard the helicopter cruiser Moskva in early 1974 prior to later deployment of about a half dozen pre-production versions in service test aboard the Kiev two years later.
The Yakovlev Yak-38 Forger was the Soviet Navy's first and only operational VTOL (Vertical Take Off and Landing) multi-role combat aircraft. Outwardly similar in design to the British-built Harrier, the first prototype of the aircraft was completed on April 14, 1970, and it made its maiden flight January 15, 1971. Before production ceased, 231 aircraft were built, including 38 two-seat trainers.
Unlike the Harrier, the Forger had three jet engines, two of which provided vertical lift and the third that could be vectored to provide both vertical lift and horizontal thrust. The aircraft suffered from severe payload restrictions, particularly when operating in hot environments, such as the Indian Ocean. The Forger could not make rolling takeoffs like the Harrier but had to rise straight up, using more fuel. Following the break up of the Soviet Union, the Yak-38 saw service with the Russian Federation and Ukraine air forces, although all have been withdrawn from service. It was severely limited in range and performance and was withdrawn from service in the 1990s.
The Yakovlev Yak-141 (NATO reporting name Freestyle) was a supersonic VTOL fighter aircraft. It did not enter production. In the fall of 1991, a Yakovlev Yak-141 Freestyle plane turned into a fireball after crashing on the deck of the air-capable cruiser Admiral Gorshkov. Fortunately, the program was cancelled in 1992.
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