The Russian Air Force has begun testing of its fifth-generation supersonic aircraft, with the aim of competing with the US's F-22 Raptor and F-35 Lightning II aircraft.
With a range of 5,500km, the Sukhoi-developed PAK-FA T-50 aircraft will enter air force service in 2015.
The PAK-FA T-50 will replace the MiG-29 Fulcrum and Su-27 Flanker of the Russian Air Force, following its development as part of Sukhoi's PAK FA project, in partnership with India.
The air force will conduct PAK-FA's maiden flight in January 2010, following the completion of runway tests, which are currently underway.
The US F-22 Raptor is the world's first fifth-generation fighter, capable of conducting air-to-air and air-to-ground combat missions with near impunity.