Voice of Russia reported official testing of five of the stealth aircraft from Sukoi is scheduled to begin later this month or in April at Russia's Akhtubinsk flight test center.
The Russian Air Force is to buy 50 to 60 of the aircraft by 2020, the report said. The first few T-50 jetfighters are due to arrive at the Lipetsk training center of the Russian air force for retraining Russian military pilots next year.
The T-50 has a speed of more than 1,327 mph and a service ceiling of 65,000 feet. It will replace the Air Force's Su-27 and some of its Su-30 aircraft. It features an advanced fire control system, including an active phased array radar in the fore-body and more antennas in the wings and the aft-body, ensuring an all-round view.
The Voice of Russia said it is superior to the West's F-35 and will be offered for sale to other countries.