Wednesday, July 23, 2008

China licensed co-production of the helicopter Mi-17

China licensed co-production of the helicopter Mi-17
July 23, 2008: In 1990, the PRC placed its first order of military hardware from its old rival Soviet Union since the end of Cold War. The order came as 24 examples of the Mil Mi-17 multirole helicopters, a derivative of the Mi-8 transport helicopter developed by the Mil Design Bureau in the 1960s. The Mi-17 is the export designation, and the version in service with the Russian Army is designated Mi-8MT. These helicopters were produced by the Ulan-Ude Aviation Plant and delivered to the PLA in 1991. The deal also marked the beginning of the multibillion dollars arms trade between PRC and Russia in the following decades. In 1995, the PLA ordered an additional 60 examples in the improved Mi-171 variant and received these helicopters in 1997. The PLA was pleased with the performance of these helicopters and more examples were acquired in the next few years. By early 2003, the PLA had reportedly received 191 Mi-17, Mi-171, and Mi-17V5 helicopters. This figure increased to 216 with the order of 25 Kazan-built M-17V-7 helicopters in 2003/04. By 2007, the total number of the Mi-17/171 helicopters in service with the PLA had reached about 250. The latest purchases have shifted to the Mi-17-V5/V7 variant manufactured by the Kazan Helicopter Plant JSC. The Mi-17V5 differs to the Ulan-Ude-built Mi-171 in its 'dolphin' nose, more powerful TV3-117VM engine with new auxiliary power unit, an extra port door on the starboard side, and flat rear fuselage ramp for easier access. The improved Mi-17V7 variant features a more powerful VK-2500 engine for full performance in hot and high conditions. Design The Mi-17/171 has a conventional design, with a large five-bladed main rotor mounted over the powerpack at the fuselage midsection a three-bladed tail rotor. Twin turboshaft engines are mounted on top of the fuselage with two round air intakes just above the cockpit and rounded exhaust ports aft. The engine intakes of the Mi-17 series have deflectors to separate solid particles in the air (sand, dust etc.) and prevent them from ingestion. The tail boom tapers to the small, swept-back, and tapered fin with rotor on the port side, with small flats mounted forward of the fin. The Mi-17/171 has a round nose with glassed-in cockpit, a large sliding door forward on the portside, and a clamshell freight-loading door in the rear. The Mi-17-V5/V7 has a solid ‘dolphin’ nose, large sliding doors on both sides of the fuselage, and a single flat ramp giving easier access. The landing gear is a non-retractable tricycle type with a twin-wheel nose unit. On each side of the fuselage there is a pod for an external fuel tank. A box-shape device attached to the lower part of the rail beam houses the electronic countermeasures (ECM) system. Some Mi-17/171 helicopters in service with the PLA are fitted with an indigenous weather radar developed by 607 Institute of Wuxi, Jiangsu Province. The cockpit accommodates a crew of three (include pilot, co-pilot/navigator, and flight mechanic). The cockpit and the main cabin are heated with air condition as optional. The main cabin can carry up to 24 equipped soldiers, or 30 passengers, or 20 stretcher patients. The seats can be removed to carrying 4,000kg of cargo. Alternatively the helicopter can carry 3,000kg large-size cargo externally under sling. The helicopter has internal winch facilities in its main cabin and tie-down rings on the floor for cargo transport. An electrically-operated hoist (300kg) is fitted above the forward slide door on the port side for rescue missions. The helicopter is equipped with fire suppression and de-icing system to increase its survivability. Armament The Mi-17/171 helicopter is capable of carrying troops and cargo for air assault of infantry troops, special force team insertion, and reply of ground troops. The Mi-8 helicopters in Russian Army and many other countries have also often been used for conducting armed attacks and providing close air support with unguided rockets and machine guns. The Mi-17s sold to China were unarmed, but the PLA managed to fit these helicopters with external weapon pylons similar to those used by the Russian Army. External stores are mounted on weapons racks on each side of the fuselage, with a total of six hardpoints. So far Mi-17s in service with the PLA have been seen carrying the 12.7mm machine gun pod, 57/68mm unguided rocket launcher, 250/500kg free-fall bomb, or TY-90 air-to-air missile according to their missions. Powerplant A PLAAF Mi-17V7 search & rescue variant with under-nose TV/FLIR unit (Chinese Internet) The Mi-17 and Mi-171 are powered by two Klimov TV3-117MT turboshaft engines, each rated at 1,950hp. The helicopter can still take-off even with one engine shut down. An auxiliary power unit (APU) enables engine starts at altitudes up to 6,000m. The Mi-17-V5 is powered by two TV3-117VM(A) engines, each rated at 2,200hp. The latest Mi-17V7 has two VK-2500 turboshaft engines, each rated at 2,400hp. The VK-2500 engine also has a full-authority digital engine control (FADEC) for 'hot and high' conditions. The helicopter carries 1,870 litres of fuel in two flexible internal tanks and two external tanks. The total fuel capacity can be increased to 3,700 litres by installing up to two ferry tanks in the cabin. Some Mi-17/171s in service with the PLA are seen being fitted with internal and external fuel tanks for extended range. Licensed Co-Production In March 2007, the Russian Mil Moscow Helicopter Plant JSC set up a joint venture “Sichuan Lantian Helicopter Co. Ltd.” in Chengdu, Sichuan Province to repair and manufacture the Mi-17 series helicopters for both Chinese and international customers. In May 2008, Russian RIA Novosti reported that the Mi-17 production at Lantian had already begin. The plant will build 20 helicopters in 2008, using Russian Ulan-Ude-supplied kits. The production is expected to reach 80 helicopters per year eventually. The variants to be built by Lantian will include Mi-171, Mi-17V5, and Mi-17V7.

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