The Harrier jump jet will be removed from service under plans announced today in the British government's defence review.

Dating back to the 1960s, when the first generation of Harriers were built in the UK, the so-called jump jets have become an icon of aviation design for their ability to hover above the ground.

In 1969 the Royal Air Force became the first in the world to use the jets' unusual vertical take-off and landing abilities.

This distinctive feature enables the aircraft to fly in and out of areas near to the battlefield that conventional aircraft cannot reach.

And their versatility means they can be deployed anywhere in the world, either on board Royal Navy aircraft carriers or to shore bases.

Normally used to provide direct support to ground troops, the RAF says it deploys them to tackle targets such as enemy troop positions, tanks and artillery.

But the aircraft, while useful, are also relatively pricey, according to experts.

Naval Harrier jets, for example, are expensive to build and maintain as complex technology is required to enable an aircraft to land on the deck of a ship and survive exposure to the sea and subsequent corrosion, a consultant for Jane's Strategic Advisory Services said.

David Black said: "When you are talking about something that can land almost like a helicopter, that is an incredibly expensive and advanced piece of technology."