Before the experimental Cierva C.19 Mk V, autogyros had been controlled in the same way as fixed-wing aircraft, that is by deflecting the air flowing over moving surfaces such as ailerons, elevators and rudder.
The first production design in the series was the C.30, a radial-engined autogyro with a three-blade, 37 ft (11.3 m) rotor mounted on an aft-leaning tripod, the control column extending into the rear of the two cockpits.
It was followed by four improved machines designated C.30P (P here for pre-production) which differed in having a four-legged pyramid rotor mounting and a reinforced undercarriage with three struts per side.
The main alteration was a further increase in undercarriage track with revised strutting, the uppermost leg having a pronounced knee with wire bracing.
Between 1933 and 1936, de la Cierva used one C.30A (G-ACWF) to test his last contribution to autogyro development before his death in the crash of a KLM Douglas DC-2 airliner when taking off at Croydon Airfield in England on 9 December 1936.
[2] Avro obtained the licence in 1934 and subsequently built 78 examples, under their model designation, fitted with an Armstrong Siddeley Genet Major IA (known in the RAF as the Civet 1) 7-cylinder radial engine producing 140 hp (100 kW).
Forty aircraft were built in Germany as the Focke-Wulf Fw 30 Heuschrecke (Grasshopper) with a 140 hp (105 kW) Siemens Sh 14A 7-cylinder radial engine.
[5] In September 1935, five members of the Lithuanian Aero Club flew C.30A in the "air train" together with the glider Schneider Grunau Baby and the airplane de Havilland DH.60 Moth over the Baltic Sea states: Kaunas, Riga, Tallinn, Helsinki.
at RAF Halton on radar calibration work: disbanded in October 1945, the twelve survivors were sold on to civilian owners.
After an accident in June 2000, which almost left the pilot without an arm, the aircraft was handed over to the Museum of Aeronautics and Astronautics, located at the Cuatro Vientos air base (Madrid).