The British Royal Navy’s HMS Queen Elizabeth aircraft carrier has left its homeport of Portsmouth for the US to participate in the Westlant 19 exercises alongside the US Navy.

The Westlant 19 exercises off the east coast of the US will test the capabilities of the British F-35 Lightning II fighter aircraft and HMS Queen Elizabeth, which set off on 30 August.

During the deployment, a British F-35B combat jet will take off from the UK’s £3bn aircraft carrier’s flight deck for the first time. The carrier will work with up to seven British F-35Bs during Westlant 19.

Over the course of the three-month Westlant 19 deployment, the Royal Navy’s biggest vessel will take part in five weeks of testing with the aircraft from the Royal Navy and RAF.

The testing will involve realistic combat scenarios. The carrier will also host US Marine Corps F-35 fighter jets.

Westlant 19 represents a key milestone for the carrier ahead of its fully operational deployment in 2021.

HMS Queen Elizabeth commanding officer captain Steve Moorhouse said: “In addition to my core ship’s company, the fixed and rotary wing air assets, enhanced medical capability, Royal Marines and other force elements from across Defence will enhance HMS Queen Elizabeth and the UK’s Carrier Strike capability on this deployment.”

In addition to the carrier, the deployment will include the Royal Navy’s HMS Dragon Type 45 destroyer and HMS Northumberland Type 23 frigate.

The three vessels will be part of a Carrier Strike Group, which will be served by tanker RFA Tideforce.

Assets from the US Navy, US Air Force and USMC are also set to take part in Westlant 19.

The Carrier Strike Group will be supported by Merlin Mk2 and Mk4 helicopters and Wildcat attack helicopters.

UK Carrier Strike Group commander commodore Mike Utley said: “The success of last year’s deployment during which we embarked and operated the F-35B for the very first time put us ahead of the curve in terms of developmental testing between the jets and ship.

“We have a significant switch in focus this year, towards operationalising this national defence capability; turning this ship, the jets for which it has been built and all supporting units into a cohesive, agile, efficient force.”

The deployment comes after last year’s Westlant 18, during which an F-35B landed ‘backwards’ on the aircraft career for the first time.