CMK K4091 MiG-21 silnik ACA

Tuman R-25 (Tumansky R-25 ) is a Soviet, aviation turbojet engine from the Cold War period. Its first successful start was in 1971. This engine was designed by a team led by Sergey Alekseevich Gavrilov, while the UMPO and Tumanski plants were responsible for production. In total, approximately 3,200 engines of this type were created. In the R-25-300 version, the engine was 4.615 meters long with a maximum diameter of 1.19 meters. The weight of the "dry" engine of this type did not exceed 1212 kilograms. The engine in this version was able to generate a thrust of 55 kN, and with the afterburner - up to 68.5 kN. The presented engine was developed as a new power unit for the latest versions of the MiG-21 aircraft, and the work on it was based primarily on the experience and technical solutions known from the Tumański R-11 engine. At the same time, however, many changes were introduced. First of all, a completely new compressor and a new afterburner were used, the turbine was interfered with, and titanium was used on a much larger scale. The engine also uses the so-called an alarm mode that allows to achieve a thrust of 96.8 kN for several dozen seconds, at the cost of a dramatic decrease in engine life, which required a general overhaul after such an operation. Various versions of this engine were used on such aircraft as the MiG-21bis or Su-15bis. The engine was also licensed in India.