The Boeing CH-47 Chinook is an American twin-engine, tandem rotor heavy-lift helicopter. Its primary roles are troop movement, artillery placement and battlefield resupply. It has a wide loading ramp at the rear of the fuselage and three external-cargo hooks. With a top speed of 170 knots (196 mph, 315 km/h) the helicopter is faster than contemporary 1960s utility and attack helicopters. The CH-47 is among the heaviest lifting Western helicopters. Its name is from the Native American Chinook people.


The Chinook was designed and initially produced by Boeing Vertol in the early 1960s; it is now produced by Boeing Rotorcraft Systems. It is one of the few aircraft of that era – along with the fixed-wing Lockheed C-130 Hercules cargo aircraft – that remain in production and frontline service, with over 1,200 built to date. The helicopter has been sold to 16 nations with the U.S. Army and the Royal Air Force (see Boeing Chinook (UK variants)) being its largest users.
In late 1956, the United States Department of the Army announced plans to replace the Sikorsky CH-37 Mojave, which was powered by piston engines, with a new, turbine-powered helicopter.^[3] Turbine engines were also a key design feature of the smaller UH-1 "Huey" utility helicopter. Following a design competition, in September 1958, a joint Army–Air Force source selection board recommended that the Army procure the Vertol medium transport helicopter. However, funding for full-scale development was not then available, and the Army vacillated on its design requirements. Some in the Army aviation corps thought that the new helicopter should be a light tactical transport aimed at taking over the missions of the old piston-engined H-21 and H-34 helicopters, and be consequently capable of carrying about fifteen troops (one squad). Another faction in the Army aviation corps thought that the new helicopter should be much larger to be able to airlift a large artillery piece, and have enough internal space to carry the new MGM-31 "Pershing" Missile System.
Improved and more powerful versions of the CH-47 have been developed since the helicopter entered service. The U.S. Army's first major design leap was the now-common CH-47D, which entered service in 1982. Improvements from the CH-47C included upgraded engines, composite rotor blades, a redesigned cockpit to reduce pilot workload, improved and redundant electrical systems, an advanced flight control system and improved avionics.^[10] The latest mainstream generation is the CH-47F, which features several major upgrades to reduce maintenance, digitized flight controls, and is powered by two 4,733-horsepower Honeywell engines.