Commando Helicopter Force (CHF) is a unit of the Royal Navy Fleet Air Arm and an element of the Joint Helicopter Command of the British Armed Forces. Its primary role is to provide Rotary-Wing support to 3 Commando Brigade Royal Marines and other UK force elements in the amphibious environment. CHF uses a combination of transport helicopters based at Royal Naval Air Station Yeovilton in Somerset, England. History The Commando Helicopter Force was formed in 1997 to consolidate command and control of the various Fleet Air Arm and Royal Marines helicopter squadrons which supported 3 Commando Brigade under Flag Officer Naval Aviation. In 1999, CHF merged with various Royal Air Force (RAF) and Army Air Corps force elements under the Joint Helicopter Command, whilst maintaining its identity as a formed unit. Elements of the force have operated in Northern Ireland (until 2002), Sierra Leone in 2000 and Bosnia; and it was an element of the amphibious force for Operation Telic, the British involvement in the 2003 invasion of Iraq, notably supporting the landings to secure the Al-Faw Peninsula. CHF was also a major part of Joint Helicopter Command's contribution to Operation Herrick in Afghanistan. Following the Strategic Defence and Security Review of 2010, the decision was made to transfer all RAF Merlin HC3 helicopters to the Royal Navy under the command and control of Commando Helicopter Force. On 30 September 2014, the aircraft were formally handed over from the RAF to the Royal Navy; with the first Royal Navy Merlin squadron, 846 Naval Air Squadron, standing up concurrently and relocating from RAF Benson to RNAS Yeovilton on 26 March 2015. The Merlin HC3 replaced the ageing Sea King HC4 as CHF's medium-lift transport aircraft when the Sea King HC4 retired on 31 March 2016. As part of the transfer of service, the Merlin HC3 is undergoing an upgrade to the HC4 standard which includes a full mid-life upgrade of the airframe and avionics; and will 'marinise' or more accurately optimise the aircraft for ship-borne amphibious operations. Location It is based at Royal Naval Air Station Yeovilton in Somerset, England; aircraft are regularly deployed with 3 Commando Brigade, overseas and to the ships of the Joint Expeditionary Force (Maritime) (JEF(M)) which includes HMS Bulwark (Landing Platform Dock). Command and control CHF is a Fleet Air Arm asset and as such remains under the Operational Command (OPCOM) of Fleet Commander, while Operational