D-30F6

Aviadvigatel, Motorstroitel (developement), Russia
Perm (production), Russia

D-30F6 is military two-shaft, two-spool engine with mixed afterburner chamber for both inner and outer flow and with regulable exhaust nozzle. Engine is intended to be used on supersonic interceptors and fighter-bombers MiG-31. Soloviev's design team from Perm started the developement in 1972. The team comprised of two companies - Aviadvigatel and Motorstroitel. The developement was finished in 1980. As can be seen from the engine's name the engine was based on D-30 line from Il-62M and Tu-154M passenger planes. Two-spool scheme significantly lowers the specific fuel consumption on dry thrust thus significantly increases range od MiG-31 against it's predecessor, the MiG-25. Neverthenless the engine gives the plane a good altitude-speed characteristics also - top speed 3000 km/h, operation altitude 11 to 21 km and as can be seen in some sources low level flight speed 1500 km/h. Another advantage of this scheme is lower thermal radiation inside the plane's fuselage. Interesting thing is that this allowed to remove the 5 kg heavy silver coating of thermal shield around engines which was used on MiG-25. The D-30F6 is the first soviet two-spool engine with afterburner. It proved it's reliability in wide range of weather conditions during it's more than 25 years long operation service.

Construction

• inlet guide vanes
• 5-stage low-pressure compressor
• base module - separating case, 10-stage high pressure compressor (movable vanes of first stator stage, air bleed after 4th and 5th stage), tube-annular combustion chamber with 12 burners, 2-stage hight pressure turine, 2-stage low pressure turbine (both cooler by air from the compressor), rear support
• mixer case
• afterburner with four ring flame stabilisers
• jet nozzle with variable cross-section
• unit of a forward and back accessory box assembly

Reliability of the engine is provided by protection, back-up and diagnostics systems:

• low pressure rotor maximum speed limitation system and maximum turbine exit temperature limitation system;
• safety system against turbine overspeed (drive of constant revolutions);
• anti-icing system for the cowl and blades of inlet guide vanes;
• anti-surge system.

Electronic-hydraulic system of automatic engine control is duplicated by hydraulic system ensuring safety of flight and back-up function in case of electronic system malfunction. The design of the engine provides an opportunity of the parametric control of its condition aboard of the airplane. To evaluate the condition of the air and gasflowpath parts in service, the engine design provides for the inspection of all compressor and turbine blades, and also, nozzle vanes of both high pressure turbine stages.

In case of foreign objects ingestion into the engine, the design allows to replace in service separate damaged blades of the 1-st high pressure compressor stage and the entire module of low pressure compressor

Besides the original D-30F6 for MiG-31 there were a few modifications also, among others the engine for experimental twin-engine S-37 (Su-47) prototype and high altitude subsonic twin-engine M-55 plane. In the first case the engine is sometimes designates as D-30F11, the information is not confirmed. The second case engine was unaugmented D-30V12 derivate with 9000 kp (88,2 kN) of thrust. M-55 plane took of in 1988 for the first time. The engines ran reliably in extreme conditions with air temperature of -92°C. Some other variants which probably existed only on papers were to equip 5th generation fighters. They had to have increased thrust among other improvements.

D-21A1

Another engine came from the original D-30F6 design, the D-21A1. It's a two-spool engine with supersonic nozzle intended to power high-altitude supersonic bizz-jet S-21 from Sukhoi design boureau. Construction scheme is almost the same as is for D-30F6 except removed afterburner chamber. Emphasis was placed on low emissions, noise and influence on ozon layer. One adavantate of this engine was the short developement time thus low developement cost. This lead to a relatively low final price. Three D-21A1 were to power one variant of proposed plane. Competitiors for the russian engines are british Rolls-Royce engines among others. Gulfstream Aerospace joined Sukhoi at the beginning of 90s for a short period. But then technical and financial problems occured and S-21 project was cancelled.

Serial production of D-30F6 has come to the end, total approx. 1500 engines were built. Today the Aviadvigatel aims itself on service life prolongation of these engines.

MiG-31	S-37	S-21

SOME CHARACTERISTICS OF D-30F6

SOME CHARACTERISTICS OF D-21A1

Some sources of information and images:

• http://www.avid.ru
• http://www.hudi.republika.pl
• Materiály Jane's
• http://www.pwgs.org/archive/2003/03/07-03-2003.htm
• http://paralay.com/mig31m.html

Last update: 2.4.2008