Russia has confirmed that the SU-57’s test programme is now complete with production of the first batch due to start in the Gagarin factory in Komsomolsk-na-Amur in Khabarovsk region in Russia’s Far East next year.
As discussed previously, the first batch will number just twelve aircraft, and will be powered by the current AL-41F1 engine used in the trial programme. Starting from 2020 all future batches will use the new Isdeliye 30 engine, which has now been flight tested on the second prototype.
Some information has now been provided about the new Isdeliye 30 engine.
Photographs of the engine on the engine on the second prototype show that it is significantly shorter than the previous AL-41F1 engine (see caption picture), a fact which should improve its stealth performance significantly, and that it uses rounded thrust-vectoring serrated nozzles, which should also improve its stealth performance whilst making the SU-57 highly manoeuvrable.
The engine’s general designer has been identified as an engineer called Yevgeny Marchukov working at NPO Saturn in Rybinsk.
The engine will use the Lyulka brand name used by all engines used by Sukhoi fighter aircraft since the 1950s. This is taken from the name of Arkhip Lyulka, who was the engineer who was chief designer of all engines used to power Sukhoi aircraft from the 1950s until his death in 1984, including the AL-31 which powers the SU-27 and a developed version of which (the AL-41F1) also powers the current SU-35 and will power the first batch of twelve SU-57s.
A report in the Russian publication Air and Cosmos says that the engine has a compression ratio of 6.7, that air flow is 21-23 kg / s. and that temperature of the gases in front of the turbine reaches 1950-2100 degrees Kelvin. Maximum thrust is put at 17-18 tons, less than claimed by some other sources but still significantly more than the 15 tons for the AL-41F1.
There are some claims that the SU-57 with the new engine can achieve a supercruise speed without afterburner of Mach 2.1. By comparison the US F-22 can achieve a supercruise speed without afterburner of Mach 1.82.
If so then that bears out Russian claims that the SU-57 has the best performance of any fifth generation fighter either planned or in production.
Recently an article by Dmitry Gorenburg claimed that the SU-57 with its new Isdeliye 30 engine will not enter service with the Russian Aerospace Forces before 2027. This appears to be based on the assumption that development of the Isdeliye 30 only began recently.
In reality development of the Isdeliye 30 engine seems to have begun in 2009 or possibly even earlier, and (as I have discussed previously) it may also have drawn on some of the work done for the aborted AL-41 project of the 1980s.
This means that the Isdeliye 30’s development is much more advanced than Gorenburg seems to realise, with the Russians slating production of the new engine to begin in 2020 or even sooner.
Meanwhile the Russians are claiming that the fact that the SU-57 is appearing later than the F-22 and the F-35 means that it is benefitting from technological advances which place it well ahead of these aircraft,
Here for example is how Sputnik reports what a seemingly well-informed military journalist Vladimir Tuchkov has to say about the SU-57’s weapons and systems as compared with those of the F-22 and F-35 (note that he refers to the SU-57 by its previous designation T-50)
[The] T-50’s delayed start behind both the F-22 and the F-35 worked out perfectly for the developers of the plane’s onboard radar systems, giving them access to fundamentally new electronic components and technologies which were unavailable ten or even five years before. “Furthermore, Russian designers were able to take into account, as far as possible, the experience of the F-22’s radar,” the journalist wrote.
“First, it must be said that the angle of the T-50’s active phased array is installed on an incline. Because of this, the aircraft’s rcs is reduced. Going with this design, which also makes possible a reduction in power usage during operation, was made possible thanks to the excellent characteristics of the N036 Belka radar, developed to replace the N035 Irbis passive phased array antenna system.
The N036 is more effective than the N035, Tuchkov noted, but even the earlier system “remains very convincing when compared with the US AN/APG-77 radar. The Russian system finds targets with an rcs of 1 square meter at distances up to 300 km. The American radar, meanwhile, does the same up to 225 km. For targets with an rcs of 0.01 square meters, the Russian radar’s range is 90 km. For the US system these figures are not available.”
Altogether, the T-50 has six radars onboard – including one on the plane’s nose, two on its sides, two on the wings and one in the aft section. They are capable of monitoring up to 60 targets at once, and targeting up to 15.
“In addition to the radar-based visibility, the T-50 features the OLS-50M optic-electronic sensor system, which includes a thermal scanner using a QWIP-matrix with unique resolution and range characteristics. In this area…Russia is considered to be the absolute world leader,” the military observer stressed. A similar system, which enables the pilot to detect targets which have their radar systems turned off, is fitted on the F-35, albeit the US design has a smaller range. The F-22 does not have this technology.If there is one advantage of the F-35’s avionics to speak of, “it is the pilot’s helmet, which makes the aircraft ‘transparent,’” Tuchkov wrote. “That is, visibility is not limited by the cockpit windows. The whole panorama of the surrounding area is displayed in the pilot’s visors, in both the visible and the infrared spectrum. Monitoring the pilot’s head and eye movements, the computer provides the necessary panoramic viewpoint and provides the pilots with tips, and manages targeting.”
Finally, and perhaps most importantly, when it comes to armaments, here the T-50 stands out, according to the observer.
Among all the world’s existing and prospective fifth-generation fighter aircraft, “the T-50 has the most extensive missile and bomb arsenal. A total of 14 high-precision missiles and smart bombs have been developed specifically for the plane. Half have already been adopted into service; the other half are undergoing testing. The KS-172, the longest-range air-to-air missile, has a maximum range up to 400 km. This is double that of the US AIM-120D missile, which has a maximum range of 180 km.”
As for air-to-surface missiles, here too the T-50 has systems that are “at the forefront of engineering solutions,” Tuchkov noted. “Using them, the pilot has the opportunity to conduct a ‘free hunt’, with the missiles themselves choosing targets independently. The US planes, meanwhile, use missiles developed in the early 2000s, and modernized in the 2010s in the best case scenario.”