Chinese People’s Liberation Army (PLA) Air Force J-20 fifth generation fighters have encountered, intercepted and driven away unknown fighter jets during combat patrols over the East China Sea, according to reports released on October 13. Although the class of foreign aircraft encountered was not confirmed, they were referred to as “advanced warplanes like the J-20 and others” indicating that they were likely fifth generation fighters. The F-35, which is the only other class of fighter in the world of that generation that is in production and fielded at squadron level strength, is the most likely culprit and actively operates in the region in both the U.S. and Japanese fleets.

An encounter between J-20s and F-35s would be far from unprecedented with the first confirmation of such encounter having come in March 2022 from Commander of the U.S. Pacific Air Forces, Air Force General Kenneth Wilsbach. He stated at the time that the Air Force was “relatively impressed with the command and control associated with the J-20,” with the service having since invested more heavily in training F-35 units specifically to counter J-20s.

The two fighters are considered effectively in a league of their own in terms of performance, with their combination of advanced avionics and stealth capabilities being beyond those of any rival. The F-35 is a much lighter single engine aircraft which is produced on a much larger scale, while the J-20 benefits from more firepower and a significantly longer range, higher operational altitude and greater manoeuvrability.

J-20s began to be used for patrols of East and South China Seas in April, with modernised fourth generation classes such as the Su-35 and J-16 previously having shouldered the burden of such operations. The J-20s involved in the most recent encounter were from the 9th Air Brigade at Wuhu, and reportedly warned incoming aircraft as follows using radio communications: “This is the Chinese Air Force. You have approached Chinese airspace, leave immediately!” Senior Colonel Li Debing, a pilot of the brigade, informed state media outlet CCTV after the incident: “Our naval and air forces have now achieved routine management and control over the East China Sea Air Defense Identification Zone, with J-20s carrying out routine combat alert missions.”

The J-20 has formed a fast growing portion of Chinese fighter units with production having expanded considerably since the aircraft was first delivered to the PLA in 2016, and expected to expand significantly further still. The fighter’s capabilities have improved markedly, with new levels of manoeuvrability recently demonstrated fuelling speculation that the aircraft has likely integrated trust vectoring engines.

The integration of WS-10C engines from mid 2019 also introduced a supercruise capability – a key feature which the F-35 notably lacks. China and the United States are the only counties to field full squadrons of indigenous fifth generation fighters, and are currently in a neck to neck race to field the world’s first sixth generation fighters which are expected to be introduced around 2030. Technology trends portend that the gap between the two leaders’ aircraft and those produced in the rest of the world will only grow.