The Royal Air Force's new Chinook helicopters will serve as the "battlefield workhorse" on the front line for decades to come, the Defence Secretary has said.
Philip Hammond unveiled the first of 14 new Mark 6 helicopters at RAF Odiham in Hampshire today, which will increase the UK's fleet of Chinooks to 60 - the largest in Europe.
Three of the helicopters have been delivered to the RAF after a contract was signed with Boeing in 2011 as part of a £1 billion programme, the Ministry of Defence (MoD) said.
The remaining aircraft are due to arrive before the end of next year, it added.
Mr Hammond said: "The strategic importance of the Chinook Mk6 should not be under-estimated.
"These helicopters will provide a significant uplift in helicopter capability, operating as the battlefield workhorse of the RAF on the frontline for decades to come."
Chief of the Air Staff, Air Chief Marshal Sir Andrew Pulford, said the Mark 6 was "the best helicopter around", with a new digital autopilot, the ability to cruise at 135 knots and lift 10 tonnes.
"The Chinook Mark 6 represents the pinnacle of the RAF's heavy lift capability and is the most advanced Chinook helicopter we have ever operated," he said. "Chinook has proved itself time and again on operations, most recently in Afghanistan and the new Mark 6 will ensure the Chinook fleet continues to play a key role.
"From my experience you can never have too many Chinooks.
"These are the very latest version, fitted with a digital autopilot system, which will reduce the workload on the crews and allow them to do things they haven't been able to do in the past.
"It brings levels of accuracy to things like the hover, at night, in the desert, in the snow and over water, which the earlier crews could only have wished for.
"It's got to be the best helicopter around. It's the utility of the aircraft, wherever we take it, whatever we ask it to do, it does it and a little bit more as well."
All 14 Mark 6 helicopters will be delivered before the end of 2015 and are on track to be fully operational by early 2017, the MoD said.
Mr Hammond also announced a new £115 million agreement with Boeing Defence UK to maintain the engines of the RAF's fleet of Chinooks, which the MoD say will save £20 million.