An engine for the PAK FA

An Engine for the PAK FA

The competitive struggle doesn’t always suit the Russian air force

[This translation is part of a march longer, wide-ranging article, not translated here. Your friendly translator has concentrated on the information about the AL-41 engine.]

A discussion about a future of domestic aircraft engine construction is resumed each time during the Moscow Dvigateli [Engines] salon. The regular, eighth, Dvigateli-2004 exhibition began operation on 12 April. Dozens of Russian enterprises that are represented at it are involved with the whole line of motors for military and civilian air vehicles. But in the foreseeable future, undoubted leadership in the manufacturing program will be kept by the AL series of engines developed by the experimental design bureau [OKB] which Arkhip Lyul’ka founded.

A unification of forces

[Snipped.]

Salyut does everything itself

[Snipped]

Saturn’s solution

In the summer of 2003, the winner became known in the tender for the development of the engine for the fifth generation fighter – NPO Saturn. Answering a question of which role in the new engine program will be allotted to Salyut and the Ufa Motor Production Association, Yuriy Lastochkin said: “They may take part in the financing of this program and in the role of component suppliers. I think that this is a very high place in the creation of the next generation engine, considering the undoubted superiority of Saturn ahead of all the other developers and manufacturers of aircraft engines of this class in Russia.”

In conferring victory to Saturn, the Russian Federation Ministry of Defense accepted its offer that the development of the new AL-41 will be carried out by successive upgrade of the AL-31. Lastochkin explains: “Today it is necessary to speak directly: The Russian state has too few resources to be involved in parallel with several programs in the area of aircraft engine construction. One may “transcribe” Saturn’s experience at the upgrade stage and save a lot of money for the country. To extend the life for those engines which are in service today, to give work to the Russian Federation defense ministry’s repair plants, and the save money on the project for creation of the AL-41. Many elements of the AL-41 will be worked through with the AL-31 upgrade.” These motors are related in size which allows the use of the modular principle in the replacement of old elements for the new which were developed for the AL-41.

They were involved in the development of the AL-41 at the start of the 1980s, and in 1987 – 1988, the prototypes were tested on Tu-16 and MiG-25 flying laboratories. They made the first 20 engines in Moscow, and in 1998 the plant in Rybinsk began familiarization with the technologies of the production of the new motor.

Originally, the AL-41 was created in the 20-tonne thrust class for installation on the A.I. Mikoyan OKB Article 1.42 and the P.O. Sukhoy OKB “Berkut,” which were developed under the multirole tactical fighter [MFI] program. When they shut down the MFI subject, the Saturn people decided to “rescale” the AL-41 into the AL-31 dimensions. At the same time, owing to advance technical solutions, the thrust of the new engine is 14 – 16 tonnes instead of 12.5. They showed the new variant at MAKS-2001. A mock-up of the AL-41F1-A engine was demonstrated with the personal permission of president Vladimir Putin in answer to Viktor Chepkin’s request.

Besides the dimensions, the new unit is distinguished by a newly developed control system, where the engine control functions are reflects in the fighter’s “central brain.”

Despite all the clashes of the “post-Soviet” period of Russia’s history, the AL-41 has been improved steadily. Thus, in order to fulfill the Russian Federation defense ministry’s new requirements, they increased the engine’s specific thrust (kilograms of thrust to kilograms of weight) from 11:1 to 12-12.5:1. They achieved this owing to the wider application of new construction materials (ceramics, metal-ceramics and the like) and the further design improvement.

Practically each element of the engine will contain innovative solutions and materials, the enumeration of which will take more than one page of text. New solutions for controllable vectored thrust, the change of the cycle parameters, the technologies of the turbine high-load blades and compressor, the strengthening of the mono-crystalloid structure by the growth in them of reinforcing “threads” in them and so on are being used in the AL-41.

More than 1.5 billion dollars already has been invested in scientific research and experimental design work on the AL-41 counting the work in Soviet times, and another up to 300 million is need for it completion. Flight tests began in the last month of an experimental example of the aircraft engine on a flying laboratory based on the Su-27M fighter. It is planned to complete the new motor before 2006,, when the flight of the fifth generation fighter prototype is expected which is being developed by the Sukhoy Aviation Holding Company.

AL-41 technologies in the SM.146 In May 2003, Saturn and the French Snecma firm started a new large-scale project – the SM.146 engine for the Russian RRJ regional airplane which is being created by Sukhoy Civil Airplanes (GSS.)

According to the approved timetable, the SM.146 is supposed to be certified 36 months after start of the program. Bench tests are planned for the end of the year, and flight at the start of 2006. [Rest snipped about SM.146.]

The smart plant

[Snipped.]

Source: 14.04.04, Voennoe-Promyshlennyy Kur’er

So this new variant of the AL-41F may be anything from 14-16 tonnes thrust (137kN-156kN). Hence the Jane’s MAKS 03 figure given of 140kN.

Dammit. I was hoping for the original 18 tonnes force …. 😀