Retired Major General G.D. Bakshi, a well-known Indian military analyst, recently asserted that Russia's Su-57 "Felon" fighter jet, despite lacking the stealth capabilities of the American F-35 Lightning II, possesses superior overall performance compared to China's J-20 and J-36 fighters.
Bakshi made these remarks at a defense symposium held in New Delhi in February 2025. His assessment highlights the Su-57's strengths, particularly in areas beyond stealth, which is a crucial factor in the ongoing development of fifth-generation fighter aircraft.
This analysis is particularly relevant as India considers technological collaborations, such as incorporating Russian engine technology (like the Product 177S) into its own defense programs.
The Lockheed Martin F-35A is widely considered the benchmark for stealth technology. With more than 1,000 units delivered worldwide by 2025, its design minimizes radar detection.
Its radar cross-section (RCS), a measure of how detectable an object is by radar, is estimated to be between 0.001 and 0.005 square meters. This is achieved through its angular shape, the use of radar-absorbent materials, and internal weapons bays.
The F-35 also boasts an advanced AN/APG-81 Active Electronically Scanned Array (AESA) radar and a Distributed Aperture System (DAS), enhancing its ability to detect and engage targets from beyond visual range (BVR) while remaining undetected.
General Bakshi acknowledged the F-35's superior stealth, a view supported by defense experts.
The Su-57's RCS is estimated to be significantly higher, between 0.1 and 0.5 square meters, due to factors like exposed engine components, riveted panels, and, in earlier models, external weapon hardpoints.
However, Russia has been actively working to improve the Su-57's stealth characteristics. The latest versions, powered by the AL-51F1 (also known as Izdeliye 30) engine since 2022, incorporate stealth-treated thrust vector control (TVC) nozzles, which help to reduce the aircraft's infrared signature.
The aircraft's frame contains a good amount, 25% of composite materials. The composite materials and radar-absorbent coatings are a part of Sukhoi's claim of achieving a Radar Cross Section (RCS) "several orders below" that of fourth-generation fighters like the Su-35 (which has an RCS of 10-20 square meters).
While not matching the F-35's stealth, these improvements make the Su-57 a "low-observable" aircraft, which, according to Bakshi, gives it an advantage over its Chinese counterparts.
China's Chengdu J-20, the primary stealth fighter of the People's Liberation Army Air Force (PLAAF), had over 200 units in operation by 2025. Its design, featuring a tailed delta wing and forward canards, suggests a better RCS (estimated between 0.02 and 0.1 square meters) than the Su-57, according to some analyses, largely due to the extensive use of composites and radar-absorbent materials.
However, the J-20's engine development has faced challenges. Initially using WS-10C engines, the transition to the more powerful WS-15 (producing 142 kN of thrust) has been plagued by reported reliability issues, and the presence of thrust vectoring remains unconfirmed.
The J-20 is equipped with PL-15 missiles, providing a BVR engagement range of 150-200 kilometers, but its Type 1475 AESA radar and overall sensor fusion capabilities are considered less advanced than the F-35's highly integrated system.
General Bakshi's central argument rests on the Su-57's superior maneuverability and firepower. Powered by two AL-51F1 engines, providing a combined 176 kN of thrust with afterburner, the Su-57 can achieve supercruise (sustained supersonic flight without afterburners) at speeds of Mach 1.3. Its three-dimensional thrust vectoring control (3D TVC) provides exceptional agility, surpassing the heavier J-20 (which has a maximum takeoff weight of 32 tons).
The Su-57's K-77M missile has a range of 200 kilometers, comparable to or exceeding the PL-15. While the N036 Byelka radar is less sophisticated than the F-35's radar, it offers 360-degree coverage through the use of cheek-mounted arrays.
Bakshi emphasized that the Su-57 trades some stealth for enhanced performance, a compromise the J-20 cannot match, particularly in dogfights and in scenarios where heavier external payloads (up to 10 tons compared to the J-20's 8 tons) are required.
General GD Bakshi claims J-35A is also trumped by the Su-57 because of maturity, and the Russian jet's versatility. While over 20 of the Russian jets were produced by 2025, and has seen combat experience in Ukraine, J-35A is still a prototype.
While the N036 Radar and its hardpoints provide a great level of flexibility, J-35A's WS-19 engines are yet to be proven. Bakshi underlined on readiness over specifications, claiming that, "China's jets look Stealthy, but Russia's flies better".
There are dissenting opinions to Bakshi's assessment. Some analysts point to the J-20's larger production scale (200 units compared to the Su-57's approximately 20) and the J-36's potential for export as indicators of China's growing momentum in this field. They also highlight the Su-57's remaining stealth limitations, such as exposed rivets and the lack of full utilization of internal weapons bays, which could diminish its advantage over time.
However, in a South Asian operational context, where within-visual-range (WVR) engagements remain a significant possibility (as evidenced by events like the 2019 Balakot airstrike), the Su-57's superior agility could potentially outweigh its stealth deficiencies against China's less combat-proven designs.
