The Su-57 with the new AL-51F-1 engine and a flat stealth nozzle could become the most significant upgrade to the Russian fifth-generation fighter. This conclusion was reached by the foreign publication Defence Security Asia, which analyzed the prospects of the modernized version of the aircraft.

According to the authors of the publication, the main difference of the updated Su-57 will be the second-stage engine AL-51F-1 ("Product 30"), which is intended to replace the current AL-41F1. The publication notes that the new powerplant was created almost from scratch and is designed to increase thrust, improve fuel efficiency, and enhance the aircraft's effectiveness during supersonic flight without using afterburners.

Analysts pay special attention to the flat nozzle with thrust vectoring. In their opinion, this design can reduce the radar and thermal signature of the fighter while maintaining high maneuverability. It is this solution, according to the publication's analysts, that could eliminate one of the most noticeable shortcomings of the Su-57 program, which has long raised questions among foreign observers.

The publication emphasizes that engine tests began several years ago, but the program has repeatedly faced delays. Despite statements about the possible entry into service of the updated aircraft by the end of the year, the authors believe that final conclusions can only be drawn after confirmation of the serial installation of the AL-51F-1 on operational aircraft.

Earlier, military expert Evgeny Damantsev stated that the Russian fifth-generation fighter surpassed the F-22 and F-16 in maneuverability in terms of angular turn rate, approaching the best world models.