Yakovlev Yak-21


Within 3 days after the departure of the first Yak-15 and 300-AND, April 29 1946 years, there was a Council of Ministers Decree in which Yakovlev commissioned to create a new fighter with improved aerodynamics and the engine model RD-10. The plane, according to the task at hand is to develop a speed at an altitude of 5 thousand. M 850 kilometers per hour and have increased flight range of up to 700 km.


Experts quickly finished an exclusive car project with the designation Yak-17-RD10. His appearance is reminiscent of its predecessor - the Yak-15. However, there were differences: the wing consisted of a high-speed laminizirovannyh profiles, ejection seat with bronespinkoy, remade tail, the presence of armored glass in the windshield 55 mm.


The engineers had to come up with a new chassis, as in the old wing of the small does not fit. In this model, the main supports were attached to power components of fuselage and retracts into the fuselage recess. The main wheels have a size 600h180 mm and metal tail - 230h180 mm to 2 m decreased track chassis.


By September 3 1946, the plane was completely built. 26 September after ground tests, pilot Klimushkin made it only a few rulezhek, but in the air he did not pick up. At that time the aircraft is already produced commercially, and it was recognized that its subsequent development have to be machine equipped with landing gear with a nose strut. In the near future, under the designation Yak-17 produces other air unit.


July 9 1946 year was issued a new decree on the development of training aircraft with dual controls, implying retraining "aircrew on by a new fighter jet materiel."


The corresponding order was issued MAP 6 of August. According to him OKB-115 2 instructed to develop-seat aircraft, the basis of which it would be used with the base engine Jumo-004, 1 and 1946 November of the year to present it to the test. Takeoff and landing performance must meet the single-seat prototype. "The whole cockpit on the equipment must ensure the piloting of the aircraft. On airplanes are allowed to adopt reduced, and if necessary - to reduce the maximum speed. "


Training aircraft in OKB-115 first received the designation Yak-Jumo then 15V Yak-Yak-15UT, but as a result he received the final official Yak-21. This car has not been established arms, and on the site of the fuselage tank is a second cabin for the cadet. All cabins securely closed guttate lantern with 2-mja sliding parts.

Yak-21 photo

Experienced "Spark" was developed in Tbilisi. Due to the harsh terms of the transfer of the aircraft on its state tests laid even earlier than single Yak-15. The first "Spark" model with tail wheel landing gear and serving the first production machine 31-th plant raised in the air for the first time in April 1947 P.U.Fokin year.


Until the end of April 1947, the plant had to produce twenty-five aircraft with dual controls. But for various reasons, none of the assigned tasks could not be performed in time. The car behaved well in the air, but soon it became clear that developed by the time Yak-21T (another version of "Spark") to the best extent meets the requirements of the military, were frozen as a result of which the production work.

Yak-21 characteristics:

Modification   Yak-21
Wingspan, m   9.20
Length m   8.70
Height, m   2.27
Wing area, m2   14.85
  empty   1900
  takeoff weight   2700
engine's type   1 TRD RD-10
Thrust, kgf   X 1 900
Maximum speed km / h   720
Cruising speed, km / h   660
Practical range, km   380
Ceiling, m   12000
Crew   2



In the first five years following the end of World War II, there was an avalanche-like creation of new types of aircraft. The development of aircraft with reactive traction engaged almost all surviving design bureaus. It is necessary to pay tribute to the foresight of A.S. Yakovlev, who, in the rush of the race for the embodiment of revolutionary ideas, never forgot that the construction of a new aircraft is only half the battle. Training for flights and maintenance is the second part of the overall success. Therefore, almost immediately after the release of the first Yak-15, specialists began work on the training version, after which, after a number of renaming, the name Yak-21 was fixed. To get results as soon as possible, designers and customers in the person of MAP went on a number of simplifications. The main requirements were the preservation of the initial indicators during takeoff / landing and saturation of the driver's cabin with a set of equipment providing pilotage. I had to sacrifice speed data. Also, from the training aircraft, weapons were removed and the fuel reserve was reduced in order to place the second cabin in the liberated space. Flight tests did not cause any principal complaints, however, having delayed for various reasons in production, the Yak-21 did not go into the series - it was time for more advanced machines.

In my opinion it is quite boring model, which was developed on the basis of Yak-15. As for the Yak-21, the ego is also used to train pilots. He had no weapons, and instructor cabin set in place an additional fuel tank. No prominent than it is different. I do not understand why it was to create the ego, when there was a similar device Yak-15.


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