|National origin||United Kingdom|
|Designer||Juan de la Cierva|
|First flight||23 October 1928|
The Cierva C.17 was a British experimental autogyro built by Cierva Autogiro Company in England in 1928, in association with Avro (which designated it their Type 612). It was an attempt to build upon the successful Cierva C.8 design using the smaller, more streamlined fuselage of an Avro Avian IIIA as a starting point. The type was found to be underpowered, and when the first attempt at fitting a more powerful engine still did not result in acceptable performance, the design was abandoned.
- Powered by a 67 kW (90 hp) A.D.C. Cirrus III piston engine.
- C.17 Mk II
- Powered by an Avro Alpha radial piston engine.
- Crew: 1
- Capacity: 1
- Length: 28 ft 9 in (8.76 m)
- Wingspan: 19 ft 9 in (6.02 m) auxiliary wing
- Height: 11 ft 1 in (3.38 m) tail up
- Empty weight: 970 lb (440 kg)
- Gross weight: 1,455 lb (660 kg)
- Fuel capacity: 17 imp gal (20 US gal; 77 l)
- Powerplant: 1 × ADC Cirrus III 4-cylinder air-cooled in-line piston engine, 90 hp (67 kW)
- Main rotor diameter: 33 ft 3.25 in (10.1410 m)
- Main rotor area: 869 sq ft (80.7 m2)
- Propellers: 2-bladed Avro wooden fixed pitch airscrew
- Maximum speed: 90 mph (145 km/h; 78 kn)
- Minimum speed: 25 mph (22 kn; 40 km/h)
- Range: 210 mi (182 nmi; 338 km) at 70 mph (61 kn; 110 km/h)
- Endurance: 3 hours
- Rate of climb: 500 ft/min (2.5 m/s)
- Power/mass: 18.2 lb/hp (11.13 kg/kW)
- Taylor, Michael J. H. (1989). Jane's Encyclopedia of Aviation. London: Studio Editions. p. 254.
- World Aircraft Information Files. London: Bright Star Publishing. pp. File 891 Sheet 29.
- Grey, C.G., ed. (1928). Jane's all the World's Aircraft 1928. London: Sampson Low, Marston & company, ltd. p. 263c.
- "C.17". web.archive.org. 10 February 2007. Archived from the original on 10 February 2007. Retrieved 7 January 2018.CS1 maint: BOT: original-url status unknown (link)
Media related to Cierva aircraft at Wikimedia Commons