Yakovlev Ya-21
| Company type | Aircraft prototype |
|---|---|
| Industry | Aerospace |
| Founded | 1930s |
| Headquarters | Soviet Union |
| Products | Single-seat sport aircraft and fighter-trainer |
The Yakovlev Ya-21, also identified as UT-21, No.21, or No.25, was a single-seat, high-speed sport aircraft and fighter-trainer created and produced in the Soviet Union during the late 1930s.
Design and development
Originating from the Yakovlev UT-1, the Ya-21 followed a similar approach to the Yakovlev AIR-18 by substituting the original Shvetsov M-11 radial engine with an imported 220 hp (160 kW) Renault 6Q-01 inverted six-cylinder inline powerplant. The design featured an enclosed rear cockpit with a canopy that slid aft, along with a fixed undercarriage equipped with streamlined fairings (trousers and spats) and a spring steel tail-skid. Additional elements included split flaps and a fixed, forward-firing, synchronized 7.62mm ShKAS machine gun mounted on the forward fuselage decking. Plans to replace the engine on the Ya-25 variant with a Kossov MG-31F nine-cylinder radial were abandoned due to shifting priorities of the customer.[1][2]
The only Ya-21 was later modified into the No.25 prototype by exchanging the imported Renault engine for a 220 hp (160 kW) domestically produced Voronezh MV-6, which was a copy of the Renault 4P (also known as Renault Bengali). The cockpit configuration was altered as well, featuring opaque side panels without a sliding canopy, and a taller windshield designed to accommodate the gunsight.[1]
Neither the Ya-21 nor the No.25 proceeded to mass production, as Yakovlev OKB redirected its efforts towards developing combat aircraft like the Yakovlev BB-22 and Yakovlev I-26.[1]
Variants
- Ya-21
- Also known as UT-21 or No. 21, this was the only prototype built out of two planned units. It functioned as a fighter-trainer and a high-speed sport aircraft, equipped with a 220 hp (160 kW) Renault 6Q-01 engine.
- No.25
- This version was a modification of the Ya-21 featuring an open cockpit and powered by a 220 hp (160 kW) Voronezh MV-6 engine.