Facing an economic crisis accelerated by the invasion of Ukraine, Russia is advancing the development of its first (and only) 5th generation fighter, the Sukhoi Su-57. Last week, the state-owned conglomerate United Aircraft Corporation (UAC) managed to register a patent for the two-seat version of the jet “invisible to radar”. 

The document RU No. 280764 was approved by the Federal Intellectual Property Service last Saturday (17), although it was originally submitted to the body in May this year. The patent describes the Su-57 as a “two-seat multipurpose aircraft […] with a complex of equipment on board,” to “detect and destroy air, surface and ground targets at super- and subsonic flight speeds over a wide range of altitudes, as well as act as an airborne command post for network-oriented operations of mixed groups of aircraft.”

One of the missions assigned to the two-seater Su-57 is air command post, as highlighted by the patent itself. The rear cockpit is “equipped with controls for transferring control priority from one pilot to another and at least two multifunctional panoramic indicators for controlling the aircraft and weapons”, indicates the patent. 

As suggested in the past, the rear seat crewman can perform a number of roles, including managing other aircraft on the battlefield, manned or unmanned. Russia has been working on integrating the Su-57 with the S-70 Okhotnik drone, also stealth, and which should operate alongside the manned jet autonomously. Western countries such as the USA and the United Kingdom have also invested in this technology, commonly called “Ala Leal”. 

Although the patent was only registered in the last few days, there has been talk of a two-seater version of the Sukhoi Su-57 since when the Russian jet was still called by its project name, T-50 PAK-FA. However, this was India's desire and not Russia's. 

Under the FGFA program, the Indians would participate in the development and later purchase of the then T-50, including in a two-seat version for training. India, however, was dissatisfied with the delay in the project, abandoning the partnership in 2018. New Delhi chose to invest in the development of its own stealth aircraft. 

In 2021 Russia spoke again about a possible twin-seater Su-57, again with an eye on the export market.

In any case, China came out ahead, which is flying a two-seater version of the Chengdu J-20. Spotters spotted the jet at an air base in 2021, but the plane has not been officially presented until today.