On September 24, 2026, the United Aircraft Corporation (UAC) announced that it had transferred another batch of Su-57 multirole fighters to the Russian Aerospace Forces. The aircraft were factory-tested and evaluated by pilots of the Russian Ministry of Defense and then flown to their operational site. Vital, the UAC christened them as aircraft with a “new technical configuration.”
This is the second publicly reported delivery of the Su-57 to the Russian Aerospace Forces in 2026. The first consignment arrived on 9th February. Russia has not disclosed the number of planes in any 2026 batch.
That lack of numbers has turned the size of the Russian Su-57 fleet into something of an intelligence puzzle.
The Official Order Gives Us One Important Number
The firmest number available is not the number currently in Russian service, but the number Russia ordered.
In June 2019, the major contract for 76 Su-57 fighters was signed by Sukhoi and the Russian Defense Ministry, with the aircraft to equip three aviation regiments by 2028. Deliveries under that program started in 2020.
The first delivery was somewhat modest. Publicly available delivery history shows that four aircraft were delivered in 2020, two in 2021 and six in 2022. Following the war in Ukraine, however, Russian officials stopped reporting the numbers in individual batches, and aircraft identifying numbers have been gradually concealed in official imagery.
But the pace of production rose. In December 2023, Rostec announced the Komsomolsk-on-Amur Aviation Plant had delivered all the Su-57s planned for the year and that production was being boosted using a flow-assembly technology and improvements across the manufacturing chain.
Russia subsequently delivered multiple batches in 2024. UAC officially announced deliveries of Su-57 in September, November, and December 2024.
But there is an important distinction here: an official announcement that a batch was delivered does not tell us how many aircraft were in that batch.
So Is Russia Already Near 50 Su-57s?
This is where estimates begin to diverge.
A Russian aviation magazine, considering the known production history and evaluations of deliveries, reported that the Russian Aerospace Forces might presently have as many as 50 Su-57s, possibly the equivalent of two aviation regiments. It estimates about 11-12 aircraft may be delivered in 2023 and about 13 in 2024, although statistics for the following deliveries are not revealed.
That figure should therefore be treated as an estimate rather than an officially confirmed fleet strength.
There is also a more conservative outlook in open source. On the basis of identifying aircraft and tail numbers, Ukrainian military newspaper Militarnyi stated that at least 16 Su-57s could be visually confirmed in Russian service. The assessment revealed aircraft linked to the 929th State Flight Test Center and those seen at operational areas.
The core of the problem is illustrated by the gap between “at least 16 identifiable aircraft” and “up to 50 aircraft potentially in the fleet.” The number of airplanes in view is not the whole number of aircraft Russia has.
Some aircraft may be at factories, test facilities, training locations, maintenance facilities, or otherwise absent from satellite imagery at the moment an observer is looking.
The 2026 Deliveries Change the Picture
Deliveries in February and September 2026 are especially relevant, as they reveal that the manufacture of the Su-57 has continued despite the absence of detailed official numbers.
The September batch was described by UAC as having a new technical configuration. The aircraft had changed a lot from the Su-57s built at the beginning of the war and the changes will continue, depending on operational and combat experience, the company said. The updated weapons complex is designed to handle newer warheads and broaden the spectrum of missions the aircraft can execute, Russian officials claimed.
Thus, Russia is not simply designing to the original Su-57 spec. The aircraft entering service in 2026 will have collected experience from years of testing, operation, and combat use.
That makes the quality and configuration of the fleet almost as important as its raw numerical strength.
Satellite Images Add Another Piece to the Puzzle
Open-source satellite imagery has occasionally provided clues about production activity at the Komsomolsk-on-Amur plant.
Earlier reports in 2026 said as many as 15 Su-57s were sighted at one stage outside industry facilities. Such photography cannot automatically show that all of those aircraft had been accepted by the Russian Aerospace Forces. Aircraft outside hangars can include those undergoing testing, preparation, or awaiting delivery.
Nevertheless, large concentrations of completed-looking aircraft can indicate the production pipeline that official secrecy otherwise hides.
Much of this is because Russia has stopped disclosing the batch sizes that would allow observers to keep a simple running total.
The Export Programme Makes the Calculation Even More Complicated
Russia is simultaneously building the export version, the Su-57E.
In September, Rosoboronexport president Alexander Mikheev said that Russia has already signed multiple contracts with international customers for the Su-57E, and fulfillment of commitments to new customers is slated to begin in 2026. The identities of the customers were not released.
Algeria is the publicly identified export customer, with reporting indicating an order for 14 aircraft.
That means production capacity at Komsomolsk-on-Amur now has to serve both Russian and foreign requirements, although the exact production allocation is not public.
The Most Defensible Answer
So, how many Su-57s does Russia have in September 2026?
There is no officially released current fleet number.
The most acceptable conclusion is that Russia has more aircraft than can be individually confirmed by open imagery, and the often reported estimate of up to around 50 aircraft remains credible but unverified. The 76-plane contract completes the existing major purchase program up to 2028; it does not mean that 76 aircraft have already been delivered.
The most important development, therefore, may not be whether Russia has crossed an exact threshold, such as 40, 45, or 50 aircraft.
The fact is that deliveries of the Su-57 will continue in 2026, production will be sustained, and the aircraft itself will be gradually improved.
The delivery on 24 September shows the program has entered a different phase: Russia is no longer only aiming to get the Su-57 into service. It is also creating an increasing fleet and improving the aircraft with operational experience.
Until Moscow publishes batch quantities again, the exact number will rely on reconstructing contracts, production history, photographs, satellite imagery, and aircraft identification, rather than an official figure from Russia.