The PM variant of the MiG-19 fighter aircraft (NATO reporting name "Farmer") entered service with the USSR in 1956. It was one of the last designs of a long development series of the Soviet jet fighters, conceived in the USSR as the answer to the American supersonic F-100 Super Sabre. After many tests, the Mikoyan-Gurevich design bureau came up with several variants of the basic design: the MiG-19, MiG-19S, SW and P. The early versions, armed with onboard guns (the MiG-19P was also equipped with a radar and synchronized gunsight) did not satisfy the Kremlin 'top brass'. The guns had a relatively short range of fire and thus were deemed out of date. At that time it was commonly believed that the days of classic aerial engagements were over and that the role of a combat aircraft was merely that of a "flying missile launcher". Guided from the ground, it was supposed to pinpoint the target using its own radar before closing in and shooting it down with a rocket missile. Some went so far as to claim that guns on a jet aircraft were useless and a thing of the past.