The Russian Defence Ministry has now formally confirmed that the correct name of Russia’s fifth generation fighter – called “SU T50” during testing – is SU-57.
The Defence Ministry has confirmed that the first operation group of 12 will enter service in 2018 – ie. next year – with the fighter due to enter service in quantity from 2020 or 2021, when it will be re-engined with its new much more powerful “item 30” engine.
In my previous article about the SU-57 I expressed some doubt that this was its real name given that the number seemed surprisingly high, with the number of the immediately preceding Sukhoi fighter being SU-35.
The Sukhoi bureau has previously used the designations S-37 and S-47 to describe fighter concepts dating from the late 1980s and 1990s. The S-47 actually flew as a technology demonstrator in the early 2000s.
There were also a series of technology demonstrators based on the SU-27, which also flew in the 1990s and 2000s, and which the Sukhoi bureau called “SU-35” and “SU-37“. Note that these are different aircraft from the SU-35, which began to enter service in large numbers with the Russian Aerospace Forces in 2013.
The SU-37 of the 1990s is also an entirely unrelated aircraft to the S-37 fighter concept of the late 1980s, which led to and was replaced by the S-47 concept, but which never itself flew.
Lastly the Sukhoi bureau came up in the 1990s with a series of design studies for a supersonic trainer, a supersonic light fighter, and a supersonic carrier based light fighter designed specifically for use by the Russia’s aircraft carrier the Admiral Kuznetsov. All these aircraft would have shared the same airframe, which was basically a miniaturised version of the airframe of the SU-27 flying with just one of the SU-27’s AL-31 engines. The Sukhoi Bureau called these aircraft S-54 (the trainer), S-55 (the light fighter) and S-56 (the carrier based light fighter).
The designation SU-57 appears to place the new fifth generation fighter in a sequence coming after all these aircraft.
All the designations cited for these aircraft and aircraft concepts were however internal Sukhoi bureau designations, given to these aircraft and aircraft concepts by the Sukhoi bureau, not by the Ministry of Defence.
It nonetheless appears that in a change to Soviet practice the Defence Ministry has decided to go along with the “SU-57” designation for the fifth generation aircraft, this being I suspect the designation the Sukhoi bureau has given this aircraft internally and which has probably been in use inside the Sukhoi bureau to refer to this aircraft for some time.
This designation relates the SU-57 to the S-37 and S-47 concepts of the 1980s and 1990s, suggesting that the SU-57 is the culmination of a line of development which started with these aircraft, which is what many people have suspected all along.
The precise reason why the Ministry of Defence has opted to call the new aircraft SU-57 is of course academic. More important is the fact that the Ministry of Defence has given the aircraft its service name.
That shows that the aircraft has been accepted as fit for service by the Russian military, and that its entry into service is now imminent.