New Delhi, Dec. 31 -- The earliest mark of the MiG-21 (NATO Code Fishbed) to enter the IAF's inventory in 1963 was the MiG-21F-13, also referred to as the Type 74. It could carry 2 x K-13 Infra Red (IR) homing air-to-air missiles (NATO code Atoll) and had a single 37 mm NR-37 cannon and a gyro gun sight with radar ranging. The role of the aircraft was primarily air defence. This was followed in 1965 by the MiG-21PF (Type 76) which was the first version to be equipped with an Airborne Interception (AI) radar, the R1L. The MiG-21FL (Type 77), made its appearance in 1966 and was equipped with the R2L AI radar. These two versions did not have a gun and could only carry 2 x K-13 missiles. The small number of Type 74s and Type 76s were phased out...