J-20 Mighty Dragon vs Su-47 "Berkut" Firkin

China’s Chengdu J-20 and Russia’s Sukhoi Su-47 exist on opposite ends of the procurement spectrum. The J-20 is an active low-observable air superiority platform with 300 units built, functioning as the primary deep-penetration interceptor for the PLAAF. The Su-47, limited to a single prototype completed in 1997, acted strictly as an aerodynamic testbed to evaluate forward-swept wing (FSW) technology.

Development and Design

Chengdu finalized the J-20’s aerodynamic configuration around a canard-delta layout with diverterless supersonic inlets (DSI) to optimize transonic pitch authority and reduce forward-aspect radar cross-section. Early production blocks relied on Russian AL-31 turbofans before Chengdu transitioned to the domestic WS-10C, and eventually the WS-15. Sukhoi built the Su-47 around an FSW made of 90% composite materials. The design sought high pitch authority at high angles of attack and delayed stall characteristics. However, aeroelastic divergence—where structural twisting forces at high speeds risk wing failure—restricted its flight envelope. Sukhoi discarded the FSW configuration for the conventional planform later utilized on the Su-57.

Specifications and Performances

The Su-47 theoretically outpaced the J-20 with a claimed maximum speed of 2,500 km/h compared to the J-20’s 2,130 km/h, but structural load limits on the FSW prevented sustained high-speed operations. The J-20 outweighs the Su-47 with a 37,000 kg maximum takeoff weight versus 35,000 kg. Powered by twin WS-10C engines generating a combined 28,968 kgf of thrust, the J-20 relies on supercruise capability for long-range intercepts up to 5,500 km. The J-20 uses internal weapon bays to maintain its low-observable profile:

• Main ventral bay accommodates four PL-15 beyond-visual-range missiles
• Lateral bays house two PL-10 short-range missiles

The Su-47 had zero operational weapons capability, carrying no radar or armament payload during its test flights.

Deployment and usage

The PLAAF integrated the J-20 into active service in March 2017, distributing the aircraft across all five theater commands. Its doctrine dictates maritime patrols in the East China and South China Seas, penetrating hostile airspace to target support assets like AWACS or tankers. Intercepts of USAF F-35s over the East China Sea in 2022 confirmed its operational status in contested airspace. The Su-47 possesses no operational history. Sukhoi flew the sole unit during the late 1990s and early 2000s exclusively to gather telemetry on fly-by-wire software and composite manufacturing.

Conclusion

The J-20 has the absolute edge in every combat scenario. The Su-47 is an engineering dead-end; physics dictate that forward-swept wings cannot withstand sustained supersonic combat maneuvering without heavily reinforced, overweight structures that destroy the aircraft's thrust-to-weight ratio. Chengdu produced a viable platform that fulfills PLAAF mass-procurement targets and beyond-visual-range doctrine. Sukhoi extracted necessary control-law data from the Su-47 demonstrator, but rightfully abandoned the airframe in favor of conventional geometry for operational combat aircraft.