From 1962 to 1968, the first two generations of MiG21's were with the the fighter regiments. This period is characteristic of fighter regiments PVOS concurrent service narrowly specialized versions - daily front fighter MiG-21F-13, and overflow versions of the MiG-21PF and PFM, equipped with on-board radar. At the turn of the 60s and 70s, a specialized reconnaissance version of the MiG-21R comes into service. The publication continues with a description of another version in Czechoslovak Air Force - the MiG-21 M, a multipurpose fighter aircraft designed to conduct aerial combat, overflow prosecution in the PVOS system, and also to conduct attacks on ground targets
