Yakovlev Yak-20
| Yakovlev Yak-20 | |
|---|---|
| Type: | Trainer aircraft |
| Design country: | |
| Manufacturer: | |
| First flight: |
October 18, 1949 |
| Commissioning: |
only prototype |
| Production time: |
1949-1951 |
| Number of pieces: |
2 |
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The Jakowlew Jak-20 ( Russian Яковлев Як-20 ) is a Soviet training aircraft that was developed for basic training in the late 1940s, but did not go into series production in favor of the Jak-18 .
development
Although the Jak-18, as the successor to the UT-2, had been designated as the standard aircraft for beginner training and had been in mass production since 1947, Alexander Yakovlev's design office began on his own initiative at the end of the decade, without a government contract having been issued to work on another draft, ostensibly still widely available in the 250 Aero club of the Soviet Union biplane type Po-2 to replace. However, the design was more modern and, in contrast to the Jak-18, which was largely covered with fabric, was made entirely of metal. As a further special feature, it was decided not to arrange the two pilot seats one behind the other as usual, but next to one another. Jakowlew was able to fall back on the experience he had gained with his "air car" AIR-11, built in the 1930s, or its four-seater further development, the AIR-16. Great attention was paid to good-natured flight characteristics and the simplest possible construction. For the latter reason, the slats initially installed on the ZAGI's advice were removed again. After a short development and construction phase that lasted only a few months , the first prototype, entitled 20-01 , began in- house testing on October 18, 1949. In January 1950, the state tests began and were extremely unsatisfactory. Although the aircraft was easy to fly as calculated, which also included figures of simple aerobatics , the insufficient range and speed were criticized. In addition, the drive did not work properly: the engine oil got too hot while the cylinders did not reach the optimum operating temperature. The second prototype 20-02 was revised and more than 50 changes were made, the most visually obvious of which concerned a changed front cooler. In 1951 the new acceptance took place, but it was again disappointing. The aircraft had too complicated take-off behavior and poor aerobatic properties. The engine also proved to be too weak. No series order was therefore placed and further development was discontinued. The concept of a cabin with side-by-side pilot seats was only realized years later with the Jak-18T, which flew for the first time in the summer of 1967.
construction
The Jak-20 is a cantilever low - wing aircraft in all-metal construction with trapezoidal wings and a normal tail unit whose horizontal stabilizer is braced. The landing gear is not retractable and has a rear wheel configuration.
Technical specifications
| Parameter | Data |
|---|---|
| crew | 1-2 |
| span | 9.55 m |
| length | 7.06 m |
| height | 2.25 m |
| Wing area | 15.00 m² |
| Empty mass | 470 kg |
| Takeoff mass | 700 kg |
| drive | an air-cooled five - cylinder radial engine AI-10 with two-blade adjustment propeller W-515 |
| power | 60 kW (82 PS) |
| Top speed | 170 km / h |
| Landing speed | 60 km / h |
| Summit height | 2700 m |
| Range | 525 km |
| Take-off / landing runway | 70 m / 80 m |
Others
The first nose wheel version of the Jak-18, the Jak-18A, was also called Jak-20, but is not identical to the model described here.
literature
- Wilfried Bergholz: Jakowlew since 1927 . Motorbuch, Stuttgart 2017, ISBN 978-3-613-04024-3 , p. 92/93 .
- Wilfried Bergholz: Russia's great aircraft manufacturer . Jakowlew, Mikojan / Gurewitsch, Suchoj. Aviatic, Oberhaching 2002, ISBN 3-925505-73-3 , p. 62 .
- Manfred Jurleit: Jakowlew Jak-20 . In: Fliegerrevue . No. 6/1981 (340) . Military Publishing House , Berlin 1981, p. 286 .
Web links
- Яковлев Як-20. Retrieved January 12, 2017 (Russian, history, dates, and photos).
- Yakovlev Piston Trainers & Stunters. www.airvectors.net, accessed April 4, 2020 (English).