The Boeing CH-47 Chinook is a versatile, twin-engine, tandem rotor heavy-lift helicopter.

The counter-rotating rotors eliminate the need for an anti-torque vertical rotor, allowing all power to be used for lift and thrust.

It's top speed of 170 knots (196 mph, 315 km/h) was faster than utility and attack helicopters of the 1960s and even many of today. Its primary roles include troop movement, artillery emplacement and battlefield resupply. There is a wide loading ramp at the rear of the fuselage and three external-cargo hooks.

Chinooks have been sold to 16 nations; the largest users are the U.S. Army and the Royal Air Force. The H-47 is now sold by Boeing Integrated Defense Systems.

Chinook helicopters were introduced in 1962 as the CH-47 Chinook, and models A, B and C were deployed in Vietnam. As the product of a modernisation programme, which included refurbishing existing CH-47s, the first CH-47Ds were delivered in 1982 and were produced until 1994. Since its introduction some 1,179 Chinooks have been built.

The CH-47D Chinook helicopter carries out transportation of troops, artillery, supplies and equipment to the battlefield. Other roles include medical evacuation, aircraft recovery, parachute drop, search and rescue, disaster relief, fire-fighting and heavy construction.

The Chinook has a triple-hook system, which provides stability to large external loads or the capacity for multiple external loads. Large external loads such as 155mm howitzers can be transported at speeds up to 260km/h using the triple-hook load configuration.

The helicopter is equipped with two T55-L-712 turboshaft engines from Honeywell (formerly AlliedSignal), which are pod-mounted on either side of the rear pylon under the rear rotor blades. The engine provides a continuous power of 3,000shp and maximum power of 3,750shp. The Honeywell T55-714 engine, which is being fitted to CH-47D, F and G models, is equipped with FADEC (full authority digital electronic control) from Goodrich.