vehicles can be carried. The CIS Interstate Aviation Committee cancelled the Mi-6's Type Certificate in October 2002 after the crash of RA-21074 in the Taimyr Peninsula. There have also been reports that the wooden tail rotor blades have reached the end of their service life. Variants Data from: Mil's heavylift helicopters : Mi-6, Mi-10, V-12 and Mi-26 izdeliye 50 The product or article number for the V-6 prototype. V-6 (Zavod No.329 Moscow) First prototype series. Mi-6 (NATO – Hook-A) Heavy-lift civil and military transport helicopter. Mi-6A Troopships and commercial transport helicopters built to a new baseline standard with improvements in reliability and new avionics. Mi-6AYa(NATO – Hook-D) OKB designation for the Mi-6VzPU and Mi-22 airborne command posts, with SLAR. Mi-6APS (PS – poiskovo-spasahtel'nyy – search and rescue) A limited number of search and rescue helicopters converted from Mi-6A standard aircraft. Mi-6ATZ (TZ – toplivo-zapravshchik – fuel tanker) Fuel transport helicopter variant of the Mi-6A. Mi-6 Boorlak (boorlak – barge hauler) Prototype ASW/MCM helicopters, used for research into ASW equipment when delays to the mission equipment forced cancellation. Mi-6BUS(NATO – Hook-C) (Also Mi-6AYa and Mi-22) airborne command post helicopter of 1975. Mi-6L (Also Mi-6LL: Letayushchaya laboratoriya) Flying laboratory variant with D-25VF engines used for flight improvements of the Mi-6 and testbed for the powerplant of the Mi-12. Mi-6M (M – morskoy – maritime) Anti-submarine variant armed with four aerial torpedoes and ASW rockets, and equipped with various experimental ASW systems. First built in 1963 and modified in 1965 for the "Barge Hauler" program. Mi-6M (M – modifitseerovannyy – modified) A projected redesign of the Mi-6 to carry over , cancelled due to the limitations of the five-bladed rotor specified. Mi-6P (P – passazheerskiy – passenger) Passenger transport helicopter, with accommodation for 80 passengers. One prototype was converted from a stock Mi-6. Mi-6PP (PP – postanovshchik pomekh – ECM aircraft) A prototype Counter-ELINT aircraft to protect air-defense radars from enemy ECM and/or ELINT activities . Mi-6PR (Protivodeystviya Radiorazvedke) Development in 1962 for jammer/electronic warfare variant. Mi-6PRTBV (podvizhnaya raketno-tekhnicheskaya baza vertlyotnovo tipa) A few modified as mobile missile maintenance technical bases and missile transporters. Mi-6PS (PS – poiskovo-spasahtel'nyy – search and rescue) Search and rescue (SAR) helicopter developed in 1966 for pick-up of the landed Vostok and Soyuz space modules. Mi-6PSA Alternative designation, used in some sources, for the Mi-6APS. Mi-6PZh (PZh – pozharnyy – fire fighting) Fire fighting variant, with a tank