Russian Two-Seater Su-57 Stealth Jet Is Aimed At Exports, Controlling Killer Drones

RUSSIA – SEPTEMBER 27, 2019: The first joint flight of a Sukhoi S-70 Okhotnik heavy unmanned combat … [+] aerial vehicle and a Sukhoi Su-57 jet fighter. As part of a testing programme, Okhotnik has performed a fully unmanned flight into an airborne alert area. Video screen grab/Russian Defence Ministry/TASS (Photo by TASSTASS via Getty Images)


On Monday, Russia’s TASS state news agency reported that the United Aircraft Company was developing a two-seat version of the twin-engine Su-57 stealth fighter (codenamed ‘Felon’ by NATO) that could serve as a control hub for up to four high-end Okhotnik-B (“Hunter”)  stealth combat drones at once.

Russia’s defense military declined to confirm or deny the claim, made by an anonymous defense industry source. Reports of work on an Su-57 two-seater are far from new — but the drone-control rationale is. In June, Deputy Prime Minister Yuri Borisov stated “The Defense Ministry and the Sukhoi Design Bureau have plans to develop a two-pilot aircraft that will boost the export demand for this model … and it may create additional demand.”

Going further back, Sukhoi was supposed to develop a customized two-seat variant of the Su-57 called the FGFA for license production in India, but New Delhi pulled out in 2018 due to lack of progress. Whatever work did get done on FGFA may help speed up the new two-seater concept.

NELLIS AFB, NV – APRIL 25: A United States Air Force pilot (L) and weapons system officer look out … [+] the cockpit of their F-15E Strike Eagle as the jet is prepared for takeoff at Nellis Air Force Base while participating in the Joint Expeditionary Force Experiment 2006 (JEFX 06) April 25, 2006 in Las Vegas, Nevada. JEFX is a biannual test of new systems and technologies by every branch of the military in an attempt to speed their introduction into the modern battlefield. This year’s tests involve about 1,400 personnel from the United States, Great Britain, Canada and Australia studying new technologies during mock combat over the Nevada desert and center on finding better ways to communicate critical information between armed forces. (Photo by Ethan Miller/Getty Images)

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Two-seat fighter jets like the F-15E and Rafale-B are inevitably a bit heavier and less agile, but are preferred for training purposes because an instructor can sit in the rear seat and take control if necessary. As a Russian defense official told Interfax in December 2020  “This [Su-57 two-seater] can be in demand in flight personnel’s training to lower the psychological stress of inexperienced pilots, and also to perform lengthy flights over featureless terrain.”

Furthermore, in combat a Weapon Systems Officer (WSO) in the back seat can operate sensors, guided weapons and more exotic payloads like electronic warfare systems and drone command links more effectively while the pilot focuses on flying.

However, there aren’t any two-seater stealth fighters so far because a stretching out a stealth jet while maintaining low-radar-observable geometry is more difficult and costly than it would be for a conventional fighter. Finesse thus will be required to refashion the Su-57 without compromising its stealth characteristics.

A two-seater Su-57B could potentially become the first two-seat stealth fighter in service, though there are rumors China is developing a two-seat version of its Chengdu J-20 stealth fighter too.

The Su-57’s role working in tandem with the Okhotnik-B stealth drone has also been forecast for several years. Just a month after the drone made its first fight in August 2019, it was tested in autonomous mode flying in formation with a single-seat Su-57 fighter.

The emphasis on armed drone control also reflects how rapidly Russia is attempting to integrate combat drones into service after lagging behind for years in that domain, with its first armed drones being delivered to operational units in 2021.

Drone-control is becoming a standard feature in next-generation fighter concepts like the U.K.’s Tempest, the Franco-German FCAS and the U.S.’s two NGAD programs.

But how can a pilot flying a single-seat fighter adequately supervise drones while also managing his own aircraft? Likely what’s needed is robust artificial intelligence that could broadly but faithfully interpret simple instructions from said pilot, while reacting autonomously to rapidly developing combat situations. In other words, a robot to help control other robots.

Having a back-seater WSO instead could drastically enhance an Su-57’s viability as a drone controller without requiring a next-generation man-machine interface.

Felon and Hunter: a stealthy power couple?

The Su-57 has walked a long and rocky path prior to entering service in 2020. During the mid-2020s Moscow downsized its order to a mere twelve jets, and the first production-model Su-57 crashed due to a flaw in the flight control system just prior to delivery to the military. The Felon is also still making do with stopgap engines as the desired final model hasn’t entered production yet.

MOSCOW REGION, RUSSIA AUGUST 30, 2019: A fifth-generation Sukhoi Su-57 jet fighter performs a … [+] flight at the MAKS 2019 International Aviation and Space Salon, in the town of Zhukovsky. Sergei Bobylev/TASS (Photo by Sergei BobylevTASS via Getty Images)

Sergei Bobylev/TASS

However, serial production of the twin-engine fighter is finally, if slowly, underway with four Su-57s expected for delivery in 2021 towards fulfilling the current order for 76 production aircraft by 2028. Compared to the U.S. F-35 Lightning stealth jet, the Felon is significantly more agile but appears to have a much larger radar cross-section, particularly from the side and rear aspect. Generally, it’s better suited for shallow rather than deep penetration of hostile air space, and shorter-range air-to-air engagements.

The Sukhoi S-70 Okhotnik-B, meanwhile, is a large flying wing stealth drone with a combat radius of around 2,500 miles carrying up to two tons of surface-attack and air-to-air weapons. Sukhoi began flight testing two S-70 prototypes starting in 2019, with entry to service supposedly scheduled for 2024. However, there remains uncertainty as to what extent the production-model S-70 will rectify the non-low-observable characteristics of the prototypes’ engines.

RUSSIA – SEPTEMBER 27, 2019: A Sukhoi S-70 Okhotnik heavy unmanned combat aerial vehicle after the … [+] first joint flight with a Sukhoi Su-57 jet fighter. As part of a testing programme, Okhotnik has performed a fully unmanned flight into an airborne alert area. Video screen grab/Russian Defence Ministry/TASS (Photo by TASSTASS via Getty Images)


An Su-57 could serve as a command-and-control hub for multiple S-70s, broadening the pilot’s situational awareness and options for scanning or attacking from multiple angles simultaneously. The controller could assign riskier combat tasks to the drones, such as launching weapons or using active radars to search for enemy fighters, ensuring hostile sensors and weapons would detect and engage the drones rather than the manned Su-57 directing their activities.

But unlike ultra-cheap ‘Loyal Wingman’ drones like the XQ-58 Valkyrie, Okhotnik is decidedly large, expensive and non-expendable, so it may be employed in a less self-sacrificing manner.

Consider that while Okhotnik could be pre-programmed to perform missions autonomously, it might still be desirable to have a platform that can stealthily penetrate enemy airspace alongside S-70s and maintain a short-range command link allowing for more flexible employment of the drone and relaying of its surveillance data in event that its satellite-communications link is compromised.

Drone-builder Kronshtadt is also proposing a more traditional low-cost Loyal Wingman-style drone called Grom, though this does have the downside of significantly more limited combat radius of around 400 miles.

Export Focus

The two-seat Su-57 undoubtedly remains aimed at export clients, as smaller air forces often prefer fighters that can do double duty as trainers. According to Defense World, the Su-57E will likely cost around $100 million.

Russia’s top arms dealer claims five Southeast Asian countries have inquired about purchasing Su-57s. These likely include Indonesia, Malaysia, Myanmar and Vietnam, all operators of Russian jet fighters. Further afield, Algeria and even Turkey have expressed interest in the stealth jet.

Russian President Vladimir Putin (L) and his Turkish counterpart Recep Tayyip Erdogan inspect a … [+] Sukhoi Su-57 fifth-generation fighter aircraft during the MAKS 2019 International Aviation and Space Salon opening ceremony in Zhukovsky outside Moscow on August 27, 2019. (Photo by Maxim SHIPENKOV / POOL / AFP) (Photo credit should read MAXIM SHIPENKOV/AFP via Getty Images)

AFP via Getty Images

A second shot at sales to India, however, might be the ultimate prize, as New Delhi might be tempted to purchase a fully developed Su-57 two-seater, provided it was made compatible with indigenous Indian weapons.

However, such prospects remain murky due to uncertainty as to how India will balance its relationships with Washington and Moscow, and the many years before any export-model Su-57s, let alone two-seaters, become available. By then, Ankara and New Delhi may well prefer to spend money on domestic stealth fighter programs instead.

Furthermore, the Su-57E may have to compete with Sukhoi’s cheaper, export-oriented Checkmate single-engine light stealth fighter built using many Su-57 systems—though full development of Checkmate too is far from guaranteed.

Given the concerted public statements and compelling rationales, a two-seat Su-57 seems distinctly possible. However, its development beyond the prototype stage should not be taken for granted due to how financial and industrial base constraints have led to huge delays and dramatically curtailed procurement for so many big-ticket Russian defense programs entering into the 2020s.

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