Bristol Sycamore

The Bristol Type 171 Sycamore was an early helicopter built by the helicopter division of the Bristol Aeroplane Company, named for the sycamore seeds that fall with a rotating motion. It was the first British helicopter to receive a certificate of airworthiness and the first British-designed helicopter to enter service with the Royal Air Force. Typically seating up to three, it carried passengers and cargo, and the RAF used it mainly for search and rescue and casualty evacuation, notably in Malaya, Cyprus and Aden. The first prototype made its maiden flight on 25 July 1947 with a Pratt and Whitney Wasp Junior, and a single 550 hp Alvis Leonides piston engine became standard. Civil users flew it for transport, mountain rescue and survey. Production ended in 1959 after 180 had been completed.