The Russian fighter fleet spans several generations at once. The modernisation strategy focuses on upgrading 3rd and 4th generation aircraft and the gradual introduction of the 5th generation.
- 3rd generation — MiG-23/27 (largely phased out), older MiG-29s.
- 4th generation — Su-27, MiG-29, MiG-31, Su-24.
- 4++ generation — Su-35S, Su-34, Su-30SM: AESA/PESA radar, better avionics, thrust-vectoring.
- 5th generation — Su-57 (PAK-FA): stealth, sensor fusion, internal weapon bays — but in limited numbers and with uncertain operational maturity.
Lessons from Desert Storm, Kosovo and Iraqi Freedom forced Russia to invest in precision-guided munitions (PGM), C4-ISR and networked weapons. The ambition is a smaller, more modern and more deployable fleet — though that ambition is held back by budget, sanctions and industrial capacity. See § 6.7 — Future outlook.
In Ukraine the Su-57 played only a modest, mostly stand-off role and stayed far from the front. In June 2024 at least one was damaged in a Ukrainian drone strike on the test base Akhtubinsk — the first loss of the type. Numbers and operational maturity remain limited; the real combat contribution of the VKS comes from the Su-34 with glide bombs (see § 6.8).