Igla-1
The 9K310 Igla-1 system and its 9M313 missile were accepted into service in the Soviet army on 11 March 1981. The main differences from the Strela-3 included an optional Identification Friend or Foe system to prevent firing on friendly aircraft, an automatic lead and super elevation to simplify shooting and reduce minimum firing range, a slightly larger rocket, reduced drag and better guidance system extend maximum range and improve performance against fast and maneuverable targets, an improved lethality on target achieved by a combination of delayed impact fuzing, terminal maneuver to hit the fuselage rather than jet nozzle, an additional charge to set off the remaining rocket fuel (if any) on impact, an improved resistance to infrared countermeasures (both decoy flares and ALQ-144 series jamming emitters), and slightly improved seeker sensitivity.
According to the manufacturer, South African tests have shown the Igla's superiority over the contemporary (1982 service entry) but smaller and lighter American FIM-92A Stinger missile. However, other tests in Croatia did not support any clear superiority, but effectively equal seeker performance and only marginally shorter time of flight and longer range for the Igla.
According to Kolomna OKB, the Igla-1 has a Pk (probability of kill) of 0.30 to 0.48 against unprotected targets which is reduced to 0.24 in the presence of decoy flares and jamming. In another report the manufacturer claimed a Pk of 0.59 against an approaching and 0.44 against receding F-4 Phantom II fighter not employing infrared countermeasures or evasive manoeuvers.
Igla
The full-capability 9K38 Igla with its 9M39 missile was finally accepted into service in the Soviet Army in 1983. The main improvements over the Igla-1 included much improved resistance against flares and jamming, a more sensitive seeker, expanding forward-hemisphere engagement capability to include straight-approaching fighters (all-aspect capability) under favourable circumstances, a slightly longer range, a higher-impulse, shorter-burning rocket with higher peak velocity (but approximately same time of flight to maximum range), and a propellant that performs as high explosive when detonated by the warhead's secondary charge on impact.
Tests in Finland have shown that in comparison with the French Mistral, the 9K38 Igla has inferior range and seeker sensitivity and smaller warhead, but it has a superior resistance to countermeasures.
The naval variant of 9K38 Igla has the NATO reporting name SA-N-10 Grouse.
