The Russian military has signed the first contract to receive 12 fifth-generation Su-57 stealth fighters. The state-of-the-art jets are to be delivered to the armed forces next year.

“The first contract for 12 aircraft has been agreed on, and the deliveries under this contract will begin shortly,” Deputy Defense Minister Alexey Krivoruchko told reporters in Komsomolsk-on-Amur.

Praising the pace of the work by the Sukhoi aircraft manufacturer on the production of the new state-of-the-art, single-seat fighter, Krivoruchko added that engineers are finishing tests on the second-stage engines of the Su-57. The jet was known as the PAK FA and T-50 during development.

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The Su-57, whose avionics system allows autonomous battlefield calculations to assist the pilot, is expected to eventually replace the iconic, but aging, Su-27 multipurpose fighters. After making its maiden flight in 2010, and after years of research and development, Russia's fifth-generation stealth fighters could come into service in 2019, CEO of Russia's United Aircraft Corporation Yuri Slyusar stated on Friday.