Mikoyan-Gurevich MiG-17
The Mikoyan-Gurevich MiG-17 is a transonic fighter aircraft produced in the Soviet Union from 1952 and was operated by air forces internationally. The MiG-17 was license-built in China as the Shenyang J-5 and Poland as the PZL-Mielec Lim-6. The MiG-17 is still being used by the North Korean air force in the present day and has seen combat in the Middle East and Asia.
The MiG-17 was an advanced modification of the MiG-15 aircraft produced by the Soviet Union during the Korean War. Production of the MiG-17 was too late for use in that conflict and was first used in the Second Taiwan Strait Crisis in 1958. While the MiG-17 was designed to shoot down slower American bombers, it showed surprising success when used by North Vietnamese pilots to combat American fighters and fighter-bombers during the Vietnam War, nearly a decade after its initial design. This was due to the MiG-17 being more agile and maneuverable than the American F-4 Phantom and F-105 Thunderchief, which were focused on speed and long range combat, as well as the fact that MiG-17 was armed with guns, which initial models of the F-4 Phantom lacked.
Design and development
While the MiG-15bis introduced swept wings to air combat over Korea, the Mikoyan-Gurevich design bureau had already begun work on its replacement in 1949 in order to fix any problems found with the MiG-15 in combat. The result was one of the most successful transonic fighters introduced before the advent of true supersonic types such as the Mikoyan-Gurevich MiG-19 and North American F-100 Super Sabre. The design ultimately proved effective into the 1960s when pressed into subsonic dogfights over Vietnam against much faster planes that were not optimized for maneuvering in such lower speed, short-range engagements.While the MiG-15 used a Mach sensor to deploy airbrakes because it could not safely exceed Mach 0.92, the MiG-17 was designed to be controllable at higher Mach numbers. Early versions that retained the original Soviet copy of the Rolls-Royce Nene engine, the Klimov VK-1, were heavier with equal thrust. Later MiG-17s were the first Soviet fighter application of an afterburner, which burned extra fuel in the exhaust of the basic engine to give extra thrust at a high efficiency cost.
Though the MiG-17 looks very similar to the MiG-15, it had a new thinner and more highly swept wing and tailplane for speeds approaching Mach 1. While the F-86 introduced the "all-flying" tailplane, which made the aircraft more controllable near the speed of sound, this feature was not adopted on MiG aircraft until the fully supersonic MiG-19. The wing sweep was 45° near the fuselage and 42° for the outboard part of the wing. The stiffer wing resisted the tendency to bend its wingtips and lose aerodynamic symmetry unexpectedly at high speeds and wing loads.
Other easily visible differences to its predecessor were the addition of a third wing fence on each wing, the addition of a ventral fin and a longer and less tapered rear fuselage that added about one meter in length. The MiG-17 shared the same Klimov VK-1 engine, and much of the rest of its construction such as the forward fuselage, landing gear and gun installation was carried over. The first prototype, designated I-330 "SI" by the construction bureau, was flown on 14 January 1950, piloted by Ivan Ivashchenko.
File:MiG-17 Keski-Suomen ilmailumuseo 1.JPG|thumb|left|MiG-17 at the Aviation Museum of Central Finland in Jyväskylä. The paintscheme is from 2006 and is based on the idea of Luonetjärvi primary school student Anni Lundahl.
File:MiG 17A Mighty 8th.JPG|thumb|left|A North Vietnamese MiG-17 on display at the Mighty Eighth Air Force Museum.
In the midst of testing, pilot Ivan Ivashchenko was killed when his aircraft developed flutter, which tore off his horizontal tail, causing a spin and crash on 17 March 1950. Lack of wing stiffness also resulted in aileron reversal which was discovered and fixed. Construction and tests of additional prototypes "SI-2" and experimental series aircraft "SI-02" and "SI-01" in 1951, were generally successful. On 1 September 1951, the aircraft was accepted for production, and formally given its own MiG-17 designation after so many changes from the original MiG-15. It was estimated that with the same engine as the MiG-15's, the MiG-17's maximum speed is higher by 40–50 km/h, and the fighter has greater maneuverability at high altitude.
Serial production started in August 1951, but large quantity production was delayed in favor of producing more MiG-15s so it was never introduced in the Korean War. It did not enter service until October 1952, when the MiG-19 was almost ready to be flight tested. During production, the aircraft was improved and modified several times. The basic MiG-17 was a general-purpose day fighter, armed with three cannons, one Nudelman N-37 37 mm cannon and two 23 mm with 80 rounds per gun, 160 rounds total. It could also act as a fighter-bomber, but its bombload was considered light relative to other aircraft of the time, and it usually carried additional fuel tanks instead of bombs.
Although a canopy that provided clear vision to the rear—necessary for air-to-air combat, like the F-86—was designed, production MiG-17Fs got a cheaper rear-view periscope, which still appeared on Soviet fighters as late as the MiG-23. By 1953, pilots got safer ejection seats with protective face curtains and leg restraints like the Martin-Baker seats in the West. The MiG-15 had suffered for its lack of a radar gunsight, but in 1951, Soviet engineers obtained a captured F-86 Sabre from Korea, and copied the optical gunsight and SRD-3 gun ranging radar to produce the ASP-4N gunsight and SRC-3 radar. The combination proved deadly over the skies of Vietnam against aircraft such as the F-4 Phantom, whose pilots lamented that guns and radar gunsights had been omitted as obsolescent.
The second prototype variant, "SP-2", was an interceptor equipped with a radar. Soon a number of MiG-17P all-weather fighters were produced with the RP-1 Izumrud radar and front air intake modifications.
In early 1953 the MiG-17F day fighter entered production. The "F" indicated it was fitted with the VK-1F engine with an afterburner by modifying the rear fuselage with a new convergent-divergent nozzle and fuel system. Early VK-1F engines that were specifically modified to equip the MIG-17F had issues during prolonged normal afterburner usage, due to the insufficient heat resistance of the alloys used for the external nozzle body and stator vanes. Because of this, early 1953-1955 production planes had a special afterburner unit that used a separate tank filled with 90% ethanol for consumption in the afterburner due to its lower combustion temperature. This engine variant was labeled VK-1F. Later production jets used a normal system with on-board fuel. The afterburner doubled the rate of climb and greatly improved vertical maneuvers. But while the plane was not designed to be supersonic, skilled pilots could just dash to supersonic speed in a shallow dive, although the aircraft would often pitch up just short of Mach 1. This became the most popular variant of the MiG-17. The next mass-produced variant, MiG-17PF incorporated a more powerful Izumrud RP-2 radar, though they were still dependent on Ground Control Interception to find and be directed to targets. In 1956 a small series was converted to the MiG-17PM standard with four first-generation Kaliningrad K-5 air-to-air missiles. A small series of MiG-17R reconnaissance aircraft were built with VK-1F engine.
5,467 MiG-17, 1,685 MiG-17F, 225 MiG-17P and 668 MiG-17PF were built in the USSR by 1958. Over 2,600 were built under licence in Poland and China.
License production
In 1955, Poland received a license for MiG-17 production. The MiG-17F was produced by the WSK-Mielec factory under the designation Lim-5. The first Lim-5 was built on 28 November 1956 and 477 were built by 1960. Apart from Poland, a number were exported to Bulgaria, designated as MiG-17F. An unknown number were built as the Lim-5R reconnaissance variant, fitted with the AFA-39 camera. In 1959–1960, 129 MiG-17PF interceptors were produced as the Lim-5P. WSK-Mielec also developed several Polish strike variants based on the MiG-17: the Lim-5M, produced from 1960; Lim-6bis, produced from 1963. Additionally some Lim-5Ps were converted in the 1970s into attack Lim-6Ms whereas other Lim-5, Lim-6bis and Lim-5P aircraft were modified for reconnaissance role as the Lim-6R, Lim-6bis R and Lim-6MR.In the People's Republic of China, an initial MiG-17F was assembled from parts in 1956, with license production following in 1957 at Shenyang. The Chinese-built version is known as the Shenyang J-5 or F-5. Similarly the MiG-17PF was manufactured there as the J-5A. Altogether 767 of these single-seater variants were built.
Operational history
MiG-17s were designed to intercept straight-and-level-flying enemy bombers, not for dogfighting with other fighters. This subsonic fighter was effective against slower, heavily loaded U.S. fighter-bombers, as well as the mainstay American strategic bombers during the MiG-17's development cycle. It was not however able to intercept the new generation of British jet bombers such as the Avro Vulcan and Handley Page Victor, which could both fly higher. The USAF's introduction of strategic bombers capable of supersonic dash speeds such as the Convair B-58 Hustler and General Dynamics FB-111 rendered the MiG-17 obsolete in front-line PVO service, and they were supplanted by supersonic interceptors such as the MiG-21 and MiG-23.MiG-17s were not available for the Korean War, but saw combat for the first time over the Straits of Taiwan when the Communist PRC MiG-17s clashed with the Republic of China F-86 Sabres in 1958.
MiG-17s downed a reconnaissance aircraft in the 1958 C-130 shootdown incident over Armenia, with 17 casualties.