NOVOSIBIRSK, March 1. /TASS/. The trials of the second-stage engine for Russia’s fifth-generation PAK FA fighter jet will begin in 2018, the vice president of the United Aircraft Corporation, Sergei Korotkov, told reporters Wednesday.

"At the moment, works are being carried out within the framework of contacts with the Russian Defense Ministry. Flight tests are under way. We plan to enter the second stage of trials next year," he said. 

United Aircraft Corporation chief Alexandr Artyukhov earlier said that trials of the PAK FA main engine are due to begin in 2017, with the entire project to be completed by 2020.

PAK FA is a Russian fifth generation fighter jet that made its maiden flight in 2010.