The twin-engined Chinook transport helicopter has two, three-bladed rotors, one at the front and one at the back.
It has room for 54 troops or can carry at least 25,000 lbs (11,340 kgs) of freight - more than its own empty weight - either inside, or slung underneath on up to three hooks.
Max speed: 185mph [298 km/h]
Length: 51ft [15.5m]
Rotor span: 60ft [18.3m]
Weight: 50,000lbs [22,680kg] max.
Range: About 300 miles
Sources: Boeing, RAF, GlobalSecurity.org
The usual crew is either two pilots or a pilot and navigator, and two loaders.
It is used by both the United States Army and the Royal Air Force (among others) to move troops, artillery, ammunition, fuel and other supplies on a battlefield.
There is room inside for two Land Rovers.
Other roles include medical evacuation and search and rescue, but also such things as disaster relief and fire-fighting.
The US Army took delivery of its first Chinook in 1962.
The manufacturer, Boeing, says more than 800 are currently in use around the world.
The RAF has more than 40 - the biggest fleet outside the US Army.
The aircraft have satellite navigation and an instrument landing system.
They have defensive systems to warn of approaching missiles and can fire off "chaff" and flares to try to divert them.
Chinooks can be fitted with two, M-134 six-barrelled guns and an M-60 machine gun.
There is also a more advanced US Army Special Operations Forces version with forward-looking infra-red cameras and terrain-following and avoidance radar, long-range fuel tanks and the ability to refuel in flight.
Planned modernisation should see the Chinook in service beyond 2030.