The UK Royal Air Force’s fleet of Merlin helicopters have completed a four-month training stint in the US, in preparation for deployment in Afghanistan by 2009.

The Merlins will provide support to ground operations and increase UK helicopter lift capacity in Afghanistan by 25%.

The helicopters, capable of carrying up to 20 personnel, will provide additional capability to the Chinook and Lynx helicopters.

Presently, the Merlin fleet is undergoing a £45m upgrade programme including installation of new rotor blades for harsh conditions and improved defensive aids against hostile threats.

Following the training, the fleet will be deployed to Afghanistan from RAF Benson in Oxfordshire.