A correspondent from Zvezda, the official TV channel of the Russian defence ministry, has been given an extraordinary opportunity to check out just how the Su-57's components are tested at Russia's largest anechoic chamber to calculate the plane's stealth characteristics.
The video shows the plane's nose section as it is irradiated with electromagnetic waves to determine the plane's expected radar visibility (a.k.a. its effective radar cross section) to enemy radar systems.
All of the Su-57's components, including its wings and engines, have been tested at the anechoic chamber, which involves putting them on a stand in the center of the chamber and rotating it, during which electromagnetic waves are applied.
"You can create an airframe out of the radar-absorbing material. This is also an option. This would be the best option, but raises the question of the aircraft's durability," Dr. Lagarkov explained.
Pointing to the example of the B-2 Spirit stealth bomber, Zvezda noted that the tradeoff for impeccable radar visibility characteristics often include reduced speed and maneuverability performance.