Formed at RAF Middle Wallop as a joint RAF /Army unit on 1 Apr 1955 to explore the operational uses of the helicopter. It was intially equipped with Sycamores and Whirlwinds. After many landings made on an area of grass marked out as a dummy carrier deck, the unit deployed to HMS Theseus in Oct 1955 for a period of intensive live deck landing practice.
The Whirlwind HAR.2s and Sycamore HC.12s and HR.14s embarked HMS Ocean and sailed for the Mediterranean. On 30 Oct 1956, the unit was renamed the Joint Helicopter Unit and subsequently took part in Operation Musketeer, lifting in elements of 45 Commando into Port Said. The unit returned to Middle Wallop and continued its operational research and evaluation work. It moved to RAF Andover but its days were numbered by a movement within the British Governments then War Office (now the Ministry of Defence) for the RAF to control the utility helicopters of the day. The Army viewed them as Battlefield Support helicopters; the RAF as Short Range Transports. The JHU was disbanded on 31 Dec 1959 to form the core of 225 Squadron
, the next day.