In mid-April 2025, photos of two new fifth-generation Su-57 fighters with tail markings "25" and "26" appeared in Russian Telegram channels dedicated to military equipment. Although there has been no official statement from the United Aircraft Corporation (UAC) or Rostec, experts believe that these aircraft are part of ongoing production, despite sanctions and technological challenges.
According to Defence-Blog, the new Su-57s may have upgraded avionics and a modified design. "Visible changes in the markings indicate that these are fresh copies, possibly released after the production line was modified," the publication notes.
It is believed that at the end of 2024, the Kremlin had between 22 and 42 Su-57 fighters in service. Despite the fact that Rostec and UAC announced the fifth-generation fighter had reached full production capacity, it is believed that less than twenty, and most likely no more than a dozen fighters, were produced last year.
Military expert Suciu attributes the slow rate of fighter production to difficulties in importing electronic components. The National Interest previously reported that Russia is using Siemens KLE 360 CNC machines, originally intended for civilian industry, to compensate for the shortage of specialized equipment.
The appearance of two new Su-57s confirms that Russia continues to develop the fifth-generation fighter program, despite external restrictions. However, the key question remains not only the quantity, but also the quality of these machines — how much their characteristics correspond to those declared, and when they will become truly mass-produced. For comparison: the American F-35 is already being produced in the hundreds, and the Chinese J-20, according to open sources, has exceeded the mark of 200 units. Whether Russia will be able to increase the production rate of the Su-57 remains to be seen.
