AVRO AND THE AUTOGIRO - 2

(Monochrome Photograph showing - A privately owned production Cierva C.19.)

Several other development machines followed, the Viper engined C8V (Type 586), the Clerget engined C8D (Type587) and the 180 hp. (134 KW) AS Lynx engined C8LMk.II (Type 611) which made use of a basic 504N fuselage and, as G-EBYY, became the first rotary winged aeroplane to fly across the English Channel. This machine was preserved and can still be seen in the Museum de l'Air, Paris. Further work, culminated in the C.19, used the diverted propeller slipstream to spin up the rotor by means of modified elevators, thus eliminating the need for groundcrew. First shown at the Aero Show at Olympia in July1929, this machine was powered by an 80 hp (60 KW) Genet II radial engine, and was the first practical Autogiro for the private owner. A total of 29 were built at Hamble.

(Colour Photograph showing - An Avro 671 Rota in the markings used for Radar calibration during World War Two.)

At this time, the change of ownership of A.V. Roe & Co. brought about the moving of its technical staff from Hamble to Newton Heath, Manchester, and Cierva's own team took over the facility, retaining some ex-Avro staff to run the factory. The Cierva Co. themselves moved out of Hamble in May 1932 and re-located at Hanworth, Middlesex. The last production C.19 was modified at Hamble to become the Mk.V. This design incorporated a direct control rotor head, i.e. the rotor could be tilted inflight by the pilot giving much improved control. Development of this machine continued at Hanworth.

This work culminated in the two-seat Cierva C.30. The prototypes were built for the Cierva Co., but a further three development aircraft were built by Avro at Newton Heath in the winter 1933/34. The design showed sufficient merit for the company to take out a further license from the Cierva Co. to build a production version as the C.30A (Avro 671). Power was supplied by a 105 hp(78 KW) Genet Major radial engine, and it was fitted with a three-bladed 37 ft (11.28m) rotor. Maximum speed was100 mph (160 Km/hour), and minimum 15 mph (24Km/hour), and was priced at £1,250. A total of 78 were built before production ended in 1938. A similar number were built in France.

Avro also sold C.30As to several European Governments and two were delivered to China. Twelve were supplied to the RAF as the Avro Rota for Army Co-operation duties prior to World War 2, followed by development and calibration duties connected with the UK 'Chain Home' defence radar during the early part of the war. By the end of the war in 1945, the helicopter had been sufficiently developed in the USA to consign the Autogiro to history.