The Sukhoi group surprised many observers during the release of the first photos showing the S70 Okhotnik stealth combat drone prototype during rolling tests in November 2018, few of them imagined that the Russian program was so advanced. The new drone performed his first flight at the beginning of the month of August. But certain aspects of the prototype, notably its propulsion provided by an AL31 engine which equips the Su30, and the shape of the nose, suggested that stealth was not the priority for Russian engineers.
A new model of the device unveiled at the MAKS2019 air show, which is taking place this week near Moscow, suggests a completely different reality. Indeed, the model, presented as the final form of the S70, seems to correct many of the reservations expressed about its stealth. Thus, the nose of the drone is elongated and refined, so as to create the break necessary to broadcast the radar waves at angles favoring radar stealth. Likewise, the general profile of the drone seems refined compared to the prototype, again so as to reduce the reflection surface and reasoning phenomena with respect to certain radar frequencies.
Above all, the propulsion of the device seems to no longer have any connection with the prototype currently being tested. Gone is the imposing nozzle coming out of the cell, the model shows an air outlet recessed in the fairing, and designed to reduce the infrared signature of the drone, according to a much more traditional approach for this type of drone. If this new overall aspect will undoubtedly strengthen the stealth of the Okhotnik, there is no longer any question of trans or supersonic flights, as one could imagine regarding the current prototype.
It remains to be seen whether these changes will actually be made to the S70, and when. As such, the Tupolev group announced ahead of the MAKS2019 show that all preparatory work concerning the PAK DA stealth strategic bomber program had been validated, and that construction of the prototype had begun. There is no doubt that the two programs, S70 and PAK DA, will enrich each other, both aircraft having the shape of a stealthy flying wing.