Tumansky R-11
# Tumansky R-11

The Tumansky R-11 (initially AM-11) is a Soviet Cold War-era turbojet engine.

## Design and development

The Tumansky R-11 was developed by A.A. Mikulin, Sergei Tumansky, and B.S. Stechkin as a twin-spool axial-flow high-altitude non-afterburning turbojet for Yakovlev Yak-25RV reconnaissance aircraft. This engine was the first Soviet twin-spool turbojet. It was first run in early 1956 and was later employed in some variants of the Yakovlev Yak-26 and Yakovlev Yak-27, as well as the Yak-28. The R-11's basic design was very successful and it was later developed into the Tumansky R-13 and Tumansky R-25 along with the experimental Tumansky R-21. A total of 20,900 R-11 engines were built.

## Variants

* R-11V-300 - first production version, high-altitude, non-afterburning
* R-11F-300 (R-37F) - afterburning version, entered production in 1956, used on MiG-21F, P and U.
* R-11AF-300 - improved version for Yakovlev Yak-28B, L and U.
* R-11F2-300 - new compressor, afterburner and nozzle, used on MiG-21P, PF and FL.
* R-11AF2-300 - R-11F2-300 adapted for Yakovlev Yak-28I, R and P.
* R-11F2S-300 - upgraded version for MiG-21PFM, PFS, S, U and UM, and for Sukhoi Su-15, UT and UM.
* Shenyang WP-7, Chinese license built copies of the R-11and

## Applications

* Sukhoi Su-15
* Mikoyan-Gurevich MiG-21
* Yakovlev Yak-25
* Yakovlev Yak-26
* Yakovlev Yak-27
* Yakovlev Yak-28

## Specifications (R-11F2S-300)

**General characteristics**

* Type: Afterburning turbojet
* Length: 4,600 mm (181.1 in)
* Diameter: 906 mm (35.7 in)
* Dry weight: 1,124 kg (2,477 lb)

**Components**

* Compressor: Axial compressor, 3-stage LP, 3-stage HP
* Turbine: one stage LP, one stage HP

**Performance**

* Maximum thrust:
* 38.7 kN (8,708 lbf) military power
* 60.6 kN (13,635 lbf) with afterburner
* Overall pressure ratio: 8.9:1
* Turbine inlet temperature: 955 °C (1,750 °F)
* Specific fuel consumption:
* 97 kg/(h·kN) (0.95 lb/(h·lbf)) at idle
* 242 kg/(h·kN) (2.37 lb/(h·lbf)) with afterburner
* Thrust-to-weight ratio: 3.51; 5.50 with afterburner.
