The Mil Mi-26 is a Soviet/Russian heavy transport helicopter. In service with civilian and military operators, it is the largest and most powerful helicopter ever to have gone into production.
Design and development
Following the incomplete development of the Mil V-12 in the early 1970s, work began on a new heavy-lift helicopter, designated "Project 90" and later allocated designation Mi-26. The new design was required to have an empty weight less than half its maximum takeoff weight. The helicopter was designed by Marat Tishchenko, protégé of Mikhail Mil, founder of the experimental OKB Mil design bureau.
The Mi-26 was designed as a heavy-lift helicopter for military and civil use, and was to replace earlier Mi-6 and Mi-12 heavy lift helicopters, with twice the cabin space and payload of the Mi-6, then the world's largest and fastest production helicopter. The primary purpose was to move military equipment like 13 metric ton (29,000 lb) amphibious armored personnel carriers, and mobile ballistic missiles, to remote locations after delivery by military transport planes such as the Antonov An-22 or Ilyushin Il-76 .
The first Mi-26 flew on 14 December 1977. The first production aircraft (serial 01-01) was rolled out on 04 October 1980. One production aircraft was destroyed during pre-delivery single-engine emergency landing procedure testing, but there were no casualties. Development was completed in 1983, and the Mi-26 was in Soviet military and commercial service by 1985.
The Mi-26 was the first factory-equipped helicopter with an eight-blade rotor . It is capable of flight in the event of power loss by one engine (depending on aircraft mission weight) thanks to an engine load sharing system. While it is only slightly heavier than the Mi-6, the Mi-26 can lift up to 20 metric tons (44,000 lb) - 8 tons more. It is the second largest and heaviest helicopter ever constructed, after the experimental V-12.
The Mi-26's unique main gearbox is relatively light but can absorb 19,725 shp, which was accomplished using a non-planetary, split-torque design. Because Mil's normal gearbox supplier said that such a gearbox couldn't be designed, the Mil Design Bureau designed the VR-26 transmission itself.
Crew: Five – 2 pilots, 1 navigator, 1 flight engineer, 1 flight technician
90 troops or 60 stretchers
20,000 kg cargo (44,090 lb)
Length: 40.025 m (131 ft 3¾ in) (rotors turning)
Rotor diameter: 32.00 m (105 ft 0 in)
Height: 8.145 m (26 ft 8¾ in)
Disc area: 804.25 m 2 (8,656.8 ft²)
Empty weight : 28,200 kg (62,170 lb)
Loaded weight: 49,600 kg (109,350 lb)
Max. takeoff weight : 56,000 kg (123,450 lb)
Powerplant : 2 × Lotarev D-136 turboshafts , 8,500 kW (11,399 shp) each
Maximum speed : 295 km/h (159 kt, 183 mph)
Cruise speed : 255 km/h (137 kt, 158 mph)
Range : 1,920 km (1,036 nmi , 1,190 mi) (with auxiliary tanks)
Service ceiling : 4,600 m (15,100 ft)