As helicopter technology continued to advance apace following the end of the Second World War, the operational flexibility offered by rotary powered aircraft resulted in a race to develop a machine with the power and range to carry both troops and supplies efficiently. The breakthrough came with the introduction of the US Sikorski H-19 Chickasaw, an aircraft which was the envy of the world, with the British military being particularly keen admirers. Having successfully evaluated a number of aircraft, a licence agreement was signed to allow Westland Aircraft based at Yeovil to produce the helicopter for British service. Named the Whirlwind, the first British build prototype flew in August 1953, with the type going on to enter Royal Navy service in July 1954.
