The F-35B is Britain's most expensive and advanced warplane.
Three more of the aircraft arrived in the UK towards the end of 2020, meaning the country now owns 21 of the jets.
In 2019, the British F-35Bs completed their first operational missions over Iraq and Syria and a year later, they departed RAF Marham for trials with the Royal Navy aircraft carrier HMS Queen Elizabeth in the North Sea.
They have also conducted tests on board HMS Queen Elizabeth off the coast of the United States.
Seven nations outside the UK and US operate F-35s on home soil: Australia, Italy, Norway, South Korea, Israel, Japan and the Netherlands.
Canada, Denmark, Singapore, Poland and Belgium have also made purchases.
Britain is expected to purchase 138 F-35Bs at most, while the US Air Force is set to own 1,763 of the F-35A models.
But what is the difference between the A, B and C models?
The F-35 jet has three variants: the F-35A conventional take off and landing (CTOL) variant, the F-35B short take off/vertical landing (STOVL) variant, and the F-35C carrier variant (CV).
The three variants perform similarly and are mainly distinguished by their different basing requirements. As a result, the F-35B and F-35C have unique ways to take off and land - due to their requirements for short take off and landing, or landing on carriers.
Using much of the same parts across the three variants allows for service-specific aircraft and for savings as a result of common parts and processes.
The F-35A is the conventional take off and landing (CTOL) variant which is designed to operate from regular runways.
It is the only version to carry an internal, 25mm cannon, while also sharing some weapons featured in the B and C variants - two air-to-air missile systems and two 2,000 lb bombs.
The F-35A is set to be the common F-35, as the US Air Force and the majority of their allied air forces and Foreign Military Sales (FMS) nations will operate the variant.
The Royal Australian Air Force declared its fleet of F-35As "ready to strike" last month, achieving Initial Operational Capability, meaning the aircraft can be deployed on operations.
Look out for the F-35A in the skies above Suffolk, as the US is set to receive its first F-35As by 2021, before eventually maintaining two operational squadrons in the county.
They are not capable of operating from the UK's Queen Elizabeth-class aircraft carriers.
The F-35B model short take off/vertical landing (STOVL) variant was designed to operate from austere, short-field bases and a range of air-capable ships, including the Queen Elizabeth class aircraft carriers.
The aircraft can also take off and land conventionally from longer runways at major bases.
Each B variant of the jet costs around $122.4m (£92m), making it the most expensive of the three aircraft programmes.
American manufacturer Lockheed Martin said it expects this cost will be reduced in the future, starting with the F-35A and then moving on to the B and C.
The aerospace and defence company said they will drive the 'A' model's price down to $80m (£60m).
Britain owns 21 F-35Bs, with an order for 27 more and eventual plans for a maximum total of 138.
The F-35C carrier variant (CV) is designed to be the US Navy’s first stealth fighter and the world's only fifth generation, long-range stealth strike fighter designed and built for aircraft carrier operations.
The F-35C variant has a larger wingspan (13.1 metres compared to the 10.7m span of the A and B) and more robust landing gear.
These qualities make the aircraft suitable for the US Navy's catapult-style assisted launches and fly-in arrestments aboard naval aircraft carriers.
Its wingtips also fold to allow for more room on the carrier's deck while deployed.
The F-35C has a greater internal fuel capacity than the other two F-35 variants and holds the same weapons arsenal as the F-35B.