Russia has developed second stage engine for its PAK FA stealth fighter jets, according to United Aircraft Corporation (UAC) official Sergei Korotkov.
Tass News Agency quoted Korotkov as saying, “Today the next-generation engine has been actually developed and soon trials will begin for it together with the T-50, for which it has been created. The design bureau is carrying out specific work. We are working on these projects together with them.”
The PAK FA, a stealth fighter jet, is also referred to as the T-50.
Currently prototype PAK FA jets fly using upgraded derivatives of Saturn’s AL-31 engines. The jets are powered by a pair of AL-41F1s, referred to as the “first stage” engine.
The AL-41F1s are meant to be placeholders for the “second stage” engine — also called the Type 30 but not officially named — which has been under development. The Type 30 is a clean sheet design, reported to have capabilities far exceeding the AL-41F1. The second stage engine is intended to have greater thrust, better fuel efficiency, and improved reliability, at a cheaper cost.
Though some reports indicated that a prototype PAK FA would test the second stage engines late in 2017, it is possible that these have been pushed into 2018.
Once the engine passes all of its testing, Russia will begin incorporating it into the stealth fighters. The PAK FA is designed to allow installation of the engines afterwards, meaning any models produced with the AL-41F1 can be upgraded later on to integrate the improved engine.