Su-57
Recent leaked videos show Russia is testing the Su-57, a new fighter jet, with flat engine nozzles. This indicates a big advancement in the jet’s development. The footage appeared in a documentary marking the 85th anniversary of the Sukhoi and MiG design bureaus, confirming earlier thoughts that the Su-57 would feature these new nozzles.
This change aims to boost the jet’s stealth by lowering its radar cross-section (RCS) and infrared (IR) signature, which are key in today’s aerial combat. The new flat nozzles support stealth while keeping the Su-57’s strong thrust-vectoring abilities, ensuring it remains agile and dominant in combat.
What Are Flat Engine Nozzles?
Flat nozzles are an important upgrade in fighter jet engines. Unlike round nozzles, which reflect radar signals strongly, flat nozzles disperse radar waves in less predictable ways. This makes it tougher for enemy radars to spot the jet, enhancing its low visibility in contested air areas. Furthermore, flat nozzles can lessen the jet’s infrared signature, which is vital for avoiding heat-seeking missiles. For the Su-57, using flat nozzles is a major improvement in its design and stealth capacity, bringing it in line with next-gen fighters that focus on survivability and effectiveness.
Why the Su-57 Needs Flat Nozzles
The Su-57 is Russia’s top fifth-generation fighter, competing with the U.S. F-22 and F-35. The Su-57’s battlefield performance is crucial, and the new flat nozzles aim to enhance its stealth and capabilities. Here’s why these upgrades matter:
- Radar Cross-Section Reduction (RCS): Radar easily detects round nozzles because they reflect signals back. Flat nozzles scatter radar waves in various directions, making it tougher for enemy radars to track the aircraft.
- Infrared Signature Management: Fighter jets produce a lot of heat, especially from engines. The flat design distributes heat more evenly, lowering the overall infrared signature. This helps the jet avoid detection by heat-seeking missiles, an important factor in modern air warfare.
- Aerodynamics and Efficiency: The flatter design could enhance exhaust airflow, cut drag, and improve fuel efficiency. For a multirole fighter like the Su-57, these enhancements could allow for longer operational ranges and better performance in combat.
Su-57’s Engine and Nozzle Improvements
The Su-57 currently uses the AL-41F1 engine, derived from the one in the Su-35. However, the jet’s future relies on the newer “Izdeliye 30” engine, also known as the AL-51F1. This next-gen engine is expected to offer better thrust and performance with improved efficiency and thrust vectoring.
The flat nozzle version of the Izdeliye 30 engine shown in the documentary is a key change from the serrated nozzle designs in prior tests. This shift signifies a focus on stealth, vital for keeping the Su-57 ahead of other fifth-generation jets. The new nozzles have a smaller shape, which boosts stealth and manoeuvrability.
How Flat Nozzles Affect Stealth and Agility
One major benefit of flat nozzles is their ability to maintain thrust-vectoring features, setting Russian fighters apart from many Western models. Thrust vectoring allows the Su-57 to direct engine exhaust in various directions for enhanced agility. The Su-57’s design includes flat nozzles, which boost its ability to quickly change directions and manoeuvre.
This feature is important for dogfighting because it helps the Su-57 evade enemy jets and missiles. Even with its flat design, the jet’s nozzles maintain thrust-vectoring capabilities, providing agility in close-range fights. The mix of stealth and performance provides the Su-57 a special advantage in aerial combat situations.
Future Applications
The use of flat nozzles on the Su-57 may impact other Russian military systems. The Izdeliye 30 engine could be adapted for use in other advanced fighter jets and unmanned combat air vehicles (UCAVs). For example, the Su-75 Checkmate, which is a lighter fifth-generation fighter, could use similar nozzle designs to boost its stealth and overall performance.
Furthermore, Russia’s S-70 Okhotnik UCAV, known for its stealth features, might also adopt flat nozzles to enhance its effectiveness in challenging air conditions. This innovation reflects a broader movement in Russian aerospace, focusing on flexible technologies applicable across various platforms to improve performance and cooperation among different military systems.
Comparing Global Innovations in Flat Nozzles
Russia’s development of flat nozzles is significant, but it follows others who have already used this design in their fighter jets. The United States’ F-22 Raptor, the first fifth-generation stealth fighter, has featured flat nozzles for years. These nozzles are part of the Pratt & Whitney F119 engines, aiding the Raptor’s stealth and agility.
Additionally, the Boeing X-32, which competed in the Joint Strike Fighter programme, also had flat nozzles, although it lost to the F-35 Lightning II. Yet, the design work on the X-32 likely influenced future nozzle designs, including those seen in the F-22 and F-35.
China is investigating flat nozzle technology, with designs emerging in the Chengdu J-20 Mighty Dragon. Although current J-20 models use round nozzles, future versions might adopt flat nozzles for improved stealth and performance. Japan’s Mitsubishi X-2 Shinshin technology demonstrator is also looking into advanced nozzle designs, including flat nozzles, as it develops next-generation stealth fighters.
Conclusion: Advancing Air Superiority
The addition of flat nozzles to the Su-57 represents a major advance in Russian jet technology. These nozzles enhance the aircraft’s stealth, lessen its infrared visibility, and maintain thrust vectoring, improving agility and survival in combat. Although Russia has made great strides with these technologies, it needs to keep innovating to match the rapid aerospace advancements of other countries.
As Russia nears final production of the Izdeliye 30 engine and the integration of flat nozzles on the Su-57, the consequences for air combat and military strategy are substantial. The ongoing evolution of the Su-57 will likely ensure its role as a leading fifth-generation fighter in global aerial warfare.
References
- TASS News, “Russia’s Sukhoi Su-57 Tests Flat Engine Nozzles,” 2024.
- Military Aerospace Review, “Flat Nozzles in Fifth-Generation Fighters”, 2023.
- Aviation Week, “The Evolution of Thrust-Vectoring and Stealth,” 2024.
