On 16 May 2026 a single photograph surfaced on the Telegram channel FighterBomber, the unofficial-but-well-sourced mouthpiece of Russia’s aerospace forces. It showed a familiar planform — the flat upper deck, the twin canted tails, the engine spacing of Sukhoi’s fifth-generation fighter — but with one new and unmistakable detail. The forward fuselage was longer. There was a second cockpit, behind the first, blistering up out of the same line. The Su-57 was now a two-seater.

Within hours, the United Aircraft Corporation (UAC) had effectively confirmed it: taxi trials of a tandem Su-57 variant are underway at Komsomolsk-on-Amur. That makes the Felon only the second fifth-generation fighter ever to grow a twin-seat sibling, after China’s J-20S. The first flight is forecast for later this year. And the official Russian framing — “primarily for export” — points squarely at New Delhi.

What changed: a stretched fuselage and a second pit

The single-seat Su-57 has a forward-fuselage length of 5.9 m from radome to canopy aft frame. The new variant adds an estimated 0.6–0.8 m of forward fuselage to accommodate a second tandem cockpit, while preserving the engine spacing, the boxy lower fuselage, and the twin canted vertical stabilisers. The bubble canopy now covers two crew stations under a stepped configuration, similar to the F-15E or Su-30SM2 layout — pilot in front, weapons-systems officer (WSO) or drone controller in the rear.

The forward CG shift created by the tandem cockpit is being absorbed in the established way: ballast moved aft, the internal weapons bay slightly reduced in length, and the centre-of-pressure tuned by minor leading-edge flap deflection schedule changes in the FCS software. Sukhoi has done this dance before with the Su-27 → Su-30 transition. The two-seater Felon does not require a new wing or new tail group — the modifications are mostly in the structure forward of the wing root and in the flight-control laws.

Why a twin-seat Felon — and why now

Russia has three distinct technical and commercial reasons for adding the back seat. First, training: every export customer with no fifth-generation experience needs a dual-control conversion trainer, and selling a fighter without one is selling an orphan. Second, mission complexity: the modern Russian doctrine of pairing a manned fifth-generation fighter with a swarm of S-70 Okhotnik-B heavy attack drones requires a dedicated drone controller, and offloading that workload from a single pilot to a back-seat operator is the path of least resistance. Third, export economics: a tandem-seat strike configuration matches the operational profile Indian Air Force officials have repeatedly described for their Multi-Role Fighter Aircraft requirement.

The Russian Telegram channel Voyevoda Veshchayet stated the case plainly in its post on 17 May: the variant is configured “primarily for export.” Indian defence press has confirmed that New Delhi will evaluate the two-seater under any future Su-57 procurement decision. The competing platform — the Sukhoi Su-75 Checkmate — has not flown, and is widely seen as dead in the water for export.

“A two-seat fifth-generation aircraft is essentially a hedge — it lets the export customer use it as a conversion trainer, an electronic-attack platform, and a manned controller for unmanned wingmen, all from the same airframe. That flexibility is what made the F-15E so successful.”

Justin Bronk — Senior Research Fellow for Airpower & Technology, RUSI

Two‑seater fifth-gen — a club of two

Until last week, only China had flown a twin-seat fifth-generation fighter: the J-20S, an enlarged tandem-cockpit derivative of the J-20A that first flew in October 2021 and is now in low-rate production. The U.S. Air Force never built a twin-seat F-22, never built a twin-seat F-35, and has been resistant to any twin-seat configuration of the F-47 Next Generation Air Dominance fighter — citing cost and the assumption that AI-driven copilots will replace human back-seaters before the type matures.

Russia disagrees. The combination of less-mature AI, more-mature export pressure, and a doctrinal commitment to manned drone control means Moscow is building exactly what Washington decided it did not need. The market test comes when New Delhi opens its next fighter solicitation.

When does it fly?

Russian aviation programmes have routinely overshot their announced first-flight dates by 12–18 months, and Komsomolsk has been working through engine and avionics supply pressures since the start of the Russia-Ukraine war. Even so, the taxi-trials photograph is consistent with a maiden flight in the fourth quarter of 2026. Whether the type can be delivered to a foreign customer before 2030 is a different question entirely — and one that depends on a very Russian variable: how quickly UAC can ramp production of the AL-51F1 (formerly Izdeliye 30) second-stage engine that the Felon family was always supposed to run on.

Sources: The Aviationist, Defence Security Asia, TURDEF, defence-blog.com, 19FortyFive.