Russia’s Su-57 Felon stealth fighter receives new avionics and weapons upgrades
February 12, 2026
Russia claims new avionics upgrades as it delivers a “large batch” of Su-57 Felons. The development highlights that the Su-57 is still very early in its maturation cycle.
UAC claims tech upgrades on new Su-57 batch
On Telegram, Russia’s United Aircraft Corporation (UAC) reported it has built and delivered a “large batch” of Sukhoi Su-57 aircraft in a “new technical configuration” to the Russian Air Force. Images released show at least two Su-57s, although analysts suggest there could be up to four.
UAC is the parent company of Sukhoi and is itself part of Rostec, and the Su-57 is produced at the Komsomolsk-on-Amur Aircraft Plant (KnAAZ).
UAC says the Su-57s “received updated onboard systems and a weapons suite.” Other reporting suggests this is a new 101KS onboard optical-electronic self-defence system.
The 101KS doesn’t generate heat waves, allowing the Su-57 to maintain its low observability. It is a passive radar that allows the aircraft to detect and track airborne targets by their heat signature.
Russia’s state-run TASS reported, “The Su-57 fighters from a large new batch delivered to the Russian Aerospace Forces on February 9 appear to have received new passive sensors for tracking aerial targets and potential threats.”
1/UAC delivered a batch of new production Su-57 multirole fighters to the Russian MoD (specifically, to the VKS). Presumably, this is the first batch delivered in 2026. The no. of aircraft in this batch is not specified; pics & video released by UAC show at least 2 (could be 4). pic.twitter.com/DTRVHReLyf
— Guy Plopsky (@GuyPlopsky) February 9, 2026
Upgrades also appear to include an improved heads-up display and additional side-looking missile-warning sensors.
The UAC quoted an unnamed Su-57 pilot saying, “The aircraft has already proven itself well during the special military operation. The new technical configuration will help expand the range of tasks assigned to this type of aircraft.”
The pilot added, “The advanced capabilities built into the aviation weapons system make it possible to employ new types of aerial munitions.”
It is unclear what type of munitions are referred to, but AGN has previously reported that Russia claims upgrades allow it to carry ‘hypersonic’ missiles.
Russia’s Su-57 fighter jet production
The news comes as videos emerge seemingly confirming the first Su-57s now in service in Algeria. Russia had claimed to have delivered the first Su-57s to Algeria in 2025.
Russia had hoped for strong export sales for its flagship fighter jet, although so far Algeria appears to be the sole customer.
The Su-57 has only been produced in anaemic numbers. Estimates for the number in Russian service range from around 20 to 35. It’s unclear if the higher number includes prototypes.
Some independent analysts estimate just 0-2 were delivered in 2025. Other estimates put the number of deliveries at 2-4.
The Ukrainian news outlet, Militaryni, reported, “The previous batch of Su-57 jets likely arrived in the spring of 2025. Before that, in November and December 2024, Russian media reported the delivery of Su-57s to the Russian Aerospace Forces.”
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Russian sanctions and ongoing upgrades
Meanwhile, leaked documents show that the Su-57 Felon has been missing some of its systems due to sanctions. The Su-57 is believed to be harder hit by sanctions than the Su-30 Flanker family.
One major development for the Su-57 was the appearance of examples finally testing the AL-51F1 engine, also known as Izdeliye 30. These engines are optimised for reduced heat signatures.
However, this announcement does not appear to be related to the new engines, and the engines do not appear to be in service yet.
UAC claims, “The aircraft can operate around the clock, including in difficult weather conditions and in complex electronic countermeasure environments.”
Featured Image: UAC
