Польшада жасалған МиГ-17 ұшағы

Polish built version of the MiG 17

The Lim 6 (NATO reporting name Fresco) was a Polish attack aircraft used between 1961 and 1992 by the Polish Air Force. It was a variant of the Mikoyan Gurevich MiG 17, which was produced in Poland as the Lim 5.

In 1955 Poland bought a licence for the manufacturing of the Soviet MiG 17, the basic jet fighter of Warsaw Pact countries. The licensed aircraft was given the designation Lim 5 (an abbreviation of: licencyjny myśliwiec – "licensed fighter"). The first Lim 5 was built in WSK Mielec on November 28, 1956, replacing the production of the Lim 2 (MiG 15bis). By production's end in 1960, 477 Lim 5s were built, becoming Poland's primary fighter. (This number includes the Lim 5R reconnaissance variant, equipped with an AFA 39 camera.) From 1959 Poland began to produce the licensed MiG 17PF interceptor, equipped with the Izumrud 5 (RP 5) radar, as the Lim 5P. By 1960, 129 were built. In the late 1950s work commenced in Poland on developing a light attack aircraft based on the Lim 5. The basic MiG 17 and Lim 5 could only carry two 250 kg bombs, which replaced their underwing fuel tanks. After building prototypes, designated 'CM', in 1960 Poles began production of an attack aircraft, Lim 5M. It introduced several modifications, mostly to allow use from rough airfields. It had double undercarriage wheels, a braking parachute, and attachments for RATO. The wing sections close to the fuselage were noticeably thicker, due to them containing additional fuel tanks. Instead of two bombs, it could carry two launchers for eight S 5 rockets (57 mm). By 1961, 60 Lim 5M's were built and from November 1961 operated by the Polish Air Force. They were not successful; thicker wings decreased performance, made handling tricky, and increased drag so much that the range was improved much less than planned. The Lim 5M was regarded only as an interim variant, and work on a more advanced design continued, testing many different ideas. In 1961, 40 Lim 6 attack aircraft were built. They introduced new blown flaps, but tests showed problems with the modified Lis 6 jet engine and the aircraft were not delivered to the Air Force. As a result, it was decided to redesign the thick wing sections with fuel tanks, blown flaps, double wheels and RATO and return to only slightly modified Lim 5 construction, with increased weapon carrying capability instead. In 1963 the Poles started production of the final variant of the attack plane, the Lim 6bis. It had standard wings and single wheels, like the Lim 5 fighter. One important change was the addition of two underwing weapon pylons close to the fuselage. Another was the fitting of a braking parachute container below the rudder. These aircraft entered the service in the Polish Air Force in 1963, but were not officially accepted until 14 September 1964. By 1964, 70 Lim 6bis were built and a number of Lim 5Ms and Lim 6s were rebuilt as Lim 6bis. A number were also converted to a reconnaissance variant Lim 6R (or Lim 6bisR) with an AFA 39 camera under a fuselage. As Lim 5P fighters became obsolete, from 1971 they were also converted to the Lim 6bis standard, under the designation of Lim 6M. Their radars were removed, but the radar covers in the central air intake remained. They were fitted with additional underwing pylons, but not with a braking parachute. Some aircraft were modified to a reconnaissance variant designated the Lim 6MR.

The Lim 6bis was armed with two NR 23 23 mm cannons (80 rounds) and one N 37D 37 mm cannon (40 rounds), like the MiG 17 (the Lim 6M was probably armed with three NR 23 23 mm cannons, like MiG 17PF). It had four underwing pylons. Typical armament consisted of two Polish made Mars 2 launchers for 16 unguided 57 mm rockets S 5 each, or 100 kg bombs. It could also carry 250 kg bombs or launchers on standard outer underwing pods, but usually they were used for 400l fuel tanks.

Lim 6bis, 6R, 6M and 6MR were used by the Polish Air Force as its most numerous attack aircraft until the 1980s. The last were finally withdrawn in 1992. Some were exported to the East Germany (German Democratic Republic), Egypt and Indonesia. Some GDR machines found themselves in Guinea Bissau in the 1980s.