The helicopter which crashed in Norfolk was a HH-60G Pave Hawk helicopter, it is an updated model of the US Black Hawk helicopter and is primarily used to conduct personnel recovery operations in hostile environments.
It is also used in civil search and rescue, medical evacuation, disaster response and humanitarian assistance.
The Pave Hawk is 64 foot long and can travel at speeds of up to 184 m.p.h (159 knots). The crew usually consists of two pilots, one flight engineer and one gunner.
The unit cost of the Pave Hawk is $40.1 million.
Source: US Air Force
More top news
David Cameron will be facing a hostile audience when he meets with leaders from the remaining 27 EU nations this week, writes James Mates.
Baroness Warsi warns reports of hate crimes are rising after a "divisive" EU campaign largely focusing on immigration spurred street abuse.
Labour has descended into crisis as several high-profile members of the shadow cabinet have quit in the past few hours. Here's who they are.