Russia is working on the development of new two-dimensional nozzles for the second-stage vector engine of the Su-57 Felon, an innovation that will enhance its stealth capabilities in the rear section without compromising the high maneuverability characteristic of next-generation Russian fighters.
The current production Su-57 and the Su-35 use the same AL-41F-1 engine, an upgraded version of the AL-31 that powers the Flanker family of fighters. This engine incorporates a three-dimensional thrust-vectoring nozzle, also known as a thrust-vectoring axisymmetric nozzle, enabling control of the pitch, yaw, and roll axes, which provides outstanding maneuverability.
For the improved version of the Su-57, called Su-57M, the AL-51F1 engine (also known as izdeliye 30) is under development. This is a next-generation turbofan engine that will offer greater thrust, reduced weight, and lower operational costs compared to its predecessors. Additionally, it will feature new two-dimensional nozzles, specifically designed to improve stealth capabilities, particularly in the aircraft’s rear section.
Initially, the AL-51F1 featured a “traditional” round nozzle with a faceted design, similar to that used in the F-35 Lightning II, but with three-dimensional thrust-vectoring capabilities. However, recent images revealed in the trailer for the documentary “Lords of the Sky”, produced by Russian Channel 7 to commemorate the 85th anniversary of the Sukhoi and MiG design bureaus, show that the final configuration of the Su-57M engine will include a new two-dimensional nozzle, a key feature to enhance the aircraft’s radar and infrared stealth.
Unlike the F-22 Raptor’s nozzle, which provides excellent pitch control by directing exhaust gases upward or downward, the Russian two-dimensional nozzle features an inclined configuration, likely designed to also enable roll control when mounted asymmetrically.
Finally, the video also showcases a new pilot helmet with a helmet-mounted display (HMD) system, currently under development. This system, already being implemented in the latest combat aircraft worldwide, is expected to be available for the Su-57M and other Russian combat aircraft in the future.
