MOSCOW, Dec. 23 (UPI) -- Russian air force Commander Lt. Gen. Viktor Bondarev said Sunday tests are under way on a fifth version of the T-50 stealth fighter jet.
Bondarev said three of the planes are undergoing factory testing at the Zhukovsky airfield near Moscow and all will be flown to Akhtubinsk in the Astrakhan region in March for more extensive examination, RIA Novosti reported.
Bondarev said the air force hopes to deploy the planes, also known as protect PAK-FA, by 2015 or 2016.
Sukhoi, which made the fourth prototype T-50, said the plane flew for the first time last week, a 40-minute flight at the Komsomolsk-on-Amur factory in Siberia. The T-50 was first unveiled in 2010 and shown publicly for the first time at the 2011 Moscow Air Show.
RIA Novosti said the plane features stealth technology, super-maneuverability, supersonic flight without afterburners and advanced avionics.
The Russian Defense ministry said it plans to buy 10 evaluation aircraft and then contract for 60 production models after 2015.