According to the latest Russian military doctrine which considers the Russian Armed Forces as defensive forces meant to protect the country and its allies while maintaining a strategic deterrence capability, this fighter follows a different design philosophy when compared to western fifth generation fighter. With its forward-optimized stealth and infrared sensor, the aircraft could be considered as a counter-stealth fighter meant to get as close as possible to adversary stealth jets before engaging them, diminishing the enemy's stealth advantage and forcing them to a close quarter dogfight, where it has the theoretical advantage due to its 3-D thrust vectoring and supermaneuverability.