The initial design was by Georges Lepère in association with the Cierva Autogiro Company and was based on the Cierva-Lepère C.L.
[2] Construction was completed in December 1934 and in January 1935 taxi-ing trials were carried out at Yeovil by Harald Penrose, after which it was transported to the Cierva flight test centre at Hanworth Aerodrome, where Juan de la Cierva flew the prototype on its first flight on 5 February 1935.
[2] Despite the poor performance of the prototype, Teddy Petter persuaded Westland to manufacture another six airframes, but further development was abandoned due to emerging work as a result of the threat of war.
On each side a large door and additional windows reached down to the bottom longeron, giving both excellent access and downward vision.
[2] During flight testing, in an attempt to improve performance, a more powerful Pobjoy Niagara III was fitted.