Three Commando Merlin Mark 4 helicopters have left the UK to join HMS Queen Elizabeth as she begins flight trials in the United States.
They have departed from RNAS Yeovilton just two days after the aircraft carrier left Portsmouth.
The Merlin Mk4 is the result of a £388 million programme to upgrade the Royal Navy's Commando Merlin Mark 3, unveiled in May.
The upgrades took place in order to ensure the Commando Helicopter Force are ready to work with HMS Queen Elizabeth.
What is new with the Mk4?
The investment has seen the helicopter become "ship-optimised", according to Dave Parry, from manufacturers Leonardo Helicopters Programme.
The Mk4 is designed to transport Royal Marines from aircraft carriers onto shoreline, replacing the role of the Sea King helicopter which retired in 2016, before being brought back a year later for a training role.
The Merlin class has seen four variants, yet the latest changes turning the Mk3 into the Mk4 is one of the biggest with each helicopter costing £15m to upgrade.
On the surface, the main difference between the Mk4 and the Mk3 is its new colour - repainted from a camouflage colour to a maritime grey, matching the colour of HMS Queen Elizabeth.
However, the inside of the aircraft is where the vast majority of work has been concentrated to turn the Mk3 into the Mk4.
Ninety-seven per cent of the aircraft wiring has been taken out, the rear fuselage has been replaced and a new instrument panel fitted.
It has been fitted with new flight controls and a new tactical computer, Mr Parry says the Mk 4 has moved "away from the 1980s/1990s technology to the latest in computer technology".
Speaking to Forces News at the aircraft's unveiling in May, one new member of the Mk 4 described the new system as a "game changer".
Two of the biggest focuses on making the aircraft suitable for life on HMS Queen Elizabeth is the introduction of a folding tail rotor and a folding motor rotor - designed so the aircraft will take up less space when onboard the aircraft carrier.
Four of the new folded Mk4s can occupy the same hangar space as one Chinook, which is also used for transporting troops. The folding process takes two-and-a-half minutes.
Up to 24 troops can be transported in the back of the Mk4. The cockpit, engine rating and gearbox rating have also been standardised.
The Ministry of Defence (MoD) says it is faster and more powerful aircraft than its predecessor.
In total, 25 Commando Merlin Mk4 helicopters will be delivered to the air wing of the Royal Marines - the Commando Helicopter Force.
The first ten are expected to come into service by the end of the year.
The first Merlin Mk1 helicopter came into service in the late 1990s.
HMS Queen Elizabeth Flight Trials
Three of the Commando Merlin Mark 4 helicopters have started their journey to join up with HMS Queen Elizabeth and begin flight trials in the US.
The trials will see F-35B fighter jets conduct 500 take-offs and landings from her deck during four months.
HMS Queen Elizabeth has a 4.5-acre flight deck where a fleet of Merlin Mk4s and F-35Bs will soon be taking off from.