production version. Mi-4A Assault transport helicopter. Mi-4AV Armed versions based on the Mi-4A. V for Vooruzhenniy (Armed). Mi-4A with additional armament. Modification of 1967 had weapons complex K-4V, included four 9М17М ATGM "Phalanga" and 96 57-mm NAR S-5M in six blocks UB-16-57U (or six 100-kg bombs or four 250-kg bombs or tanks with an incendiary substance); 185 helicopters were converted to Mi-4AV. Mi-4GF Factory designation for demilitarised Mi-4 for use in the Civil Air Fleet. Mi-4L Lyukes Six-seat VIP transport version, sometimes converted into an air ambulance helicopter. Mi-4VL Fire-fighting version of Mi-4L. Mi-4M (NATO – Hound-C) Anti-submarine warfare helicopter with searching radar station SPRS-1 ("Kurs-M"), hydroacoustic station "Baku", additional fuel tank and rescue boat with operator in under-fuselage gun turret. Mi-4ME Export modification of Mi-4M. Mi-4VM Slightly modified version of Mi-4M, differed by some avionics system. Mi-4MR Upgraded version of Mi-4VM with the searching radar station "Rubin-V" instead of "Kurs-M". Mi-4P / Mi-4VP Civil transport helicopter, with accommodation for between 8 and 11 passengers, plus eight stretchers and a medical attendant for air ambulance duties. Mi-4PL (NATO – Hound-B) Anti-submarine warfare helicopter. Mi-4PS SAR version. Mi-4S Salon VIP transport helicopter. Mi-4Skh Multi-role agricultural helicopter, with a large chemical container in the main cabin. Also used as a fire-fighting helicopter. Mi-4T Major military production version, equipped with a large diameter main rotor and bulged windows. Mi-4VM (VM-12) Anti-submarine warfare helicopter. Mi-4BT Minesweeper with floats. Mi-4RI Mi-4M equipped with the Rion experimental sonar. Mi-4MT Torpedo-carrying ASW attack (killer) aircraft derived from Mi-4M. Mi-4MU Attack helicopter. Mi-4MO Search helicopter with Oka sonar. Mi-4MS Search helicopter with Soora infra-red sensor. Mi-4FV (Mi-4KV) Photographic and guidance helicopter. Mi-4Schch "Polar version" of Mi-4FV for working at the Soviet Arctic and Antarctic research stations. Mi-4SP Special rescue modification. Mi-4PG Experimental version equipped with an external load sling system. Mi-4SV Mi-4 with improved heat insulation for working in the Far North. Mi-4N "Filin" (Horned owl) Experimental reconnaissance version intended for night-time use. Mi-4KK (Mi-4VKP) Mobile command post. Mi-4KU (Mi-4VPU) Mobile command post for controlling Air Force units. Mi-4U Target-designator version carrying the Oospekh (Success) system. Mi-4GR Mi-4 fitted with Grebeshok-3 (Haircomb-3) wide-range panoramic detection and relay radar. Mi-4TARK TV-equipped artillery reconnaissance and spotting helicopter. Mi-4MK (Mi-4PP) ECM version. Mi-4UM Radio-controlled target drone version. Harbin Z-5 Chinese military transport helicopter. Chinese production version. Harbin Z-6 Prototype turbine powered version of the Z-5, no production undertaken. Xuanfeng Chinese civil