TheYakovlev AIR-9 / AIR-9bis was a 2-seat sport aircraft designed and built in the USSR during the early 1930s.
Design and development
From 1933 Yakovlev and his design team developed a 2-seat low-wing monoplane sport aircraft with open cockpits, wooden wings, welded steel tube fuselage, powered by a Shvetsov M-11 engine. Fitted with landing flaps and automatic leading-edge slats, the AIR-9 design was submitted to a safe aircraft design competition, but was not proceeded with.[1]
The original AIR-9 design was re-worked in 1934 to include enclosed cockpits, but dispensing with the automatic slats. The tandem cockpits were fitted with sliding canopies; the forward canopy slid rearwards over the fixed centre canopy section and the rear canopy slid forwards under the centre-section.[1]
The structure of the AIR-9 followed Yavovlev's previous designs with wooden plywood and fabric covered wings, welded steel tube fabric-covered fuselage and Duralumin fabric covered tail surfaces. The fixed spatted main undercarriage was supported by struts, later fitted with trousers as well as spats, with a fixed tail-skid or tailwheel (as exhibited at the 1935 Milan airshow).[1]
The AIR-9 was powered by a single 100 hp (75 kW) Shvetsov M-11 five-cylinder air-cooled radial driving a fixed pitch 2-bladed wooden propeller, variously fitted with individual exhaust stacks, collector ring and Townend ring cowling.[1]
The AIR-9bis in flight, pilotted by Piontkovskii
AIR-9bis
In 1935 the AIR-9 was modified, or a second aircraft built, with a forward sloping windshield and re-designated AIR-9bis. The large number of variations in configuration suggest that there were more than one aircraft, but this cannot be confirmed.[1]
Operational history
The AIR-9bis was displayed at the 1935 Paris and Milan airshows, and in 1937, was flown by I.N. Vishnevskaya and Ye.M. Mednikova to set a women's altitude record in the FAI Class C category.[1][2]
Variants
AIR-9
The original open cockpit 2-seat low-wing monoplane sport aircraft design, with split flaps and automatic leading edge slats; not proceeded with.[1]
AIR-9
The original design reworked with closed cockpits and other refinements but without automatic slats. At least one built, at some stage seen with racing number 31.[1]
AIR-9bis
Further modifications prompted re-designation to AIR-9bis, introducing a forward sloping windshield and undercarriage trousers. One converted from the AIR-9 or possibly several new built aircraft, seen wearing racing number 32.[1]
Specifications (AIR-9bis)
Data from OKB Yakovlev,[1] Yakovlev aircraft since 1924[2]
General characteristics
Crew: 2
Length: 6.97 m (22 ft 10 in)
Wingspan: 10.2 m (33 ft 6 in)
Wing area: 16.87 m2 (181.6 sq ft)
Empty weight: 495 kg (1,091 lb)
Max takeoff weight: 768 kg (1,693 lb)
Fuel capacity: 63.5 kg (140 lb) fuel; 17.5 kg (39 lb) oil
