TOKYO — Japan has charged that Chinese J-15 warplanes locked fire-control radar on Japanese Air Self-Defence Force, or ASDF, F-15 jets over international waters near the disputed islands of Senkaku in the East China Sea twice, and called “dangerous” the incidents that occurred Saturday, prompting a formal protest to Beijing following their return. The protest was announced in Tokyo by Prime Minister Sanae Takaichi and Defence Minister Shinjiro Koizumi on Sunday, Dec. 7, 2025.
The J-15s took off from the carrier Liaoning — whose last voyage also attracted Japanese warships and planes — and turned on fire-control radar sporadically for a total of about three minutes in the late afternoon and around 30 minutes after dark as the Japanese F-15s tailed at a safe distance while tracking training by the carrier group, Defence Ministry officials said. The Japanese Ministry of Defence said there was no violation of Japanese airspace and no damage or injuries, but officials called the use of the fire-control radar a step that “is believed to be an action that goes beyond what is necessary for safe flight,” details first reported by AsiaOne and other regional news outlets.
Fire-control radar lock raises miscalculation risk.
Fire-control radar is one of the last things a pilot does in today’s aerial combat before a potential shootdown — for locking onto a target and feeding precise data on distance and trajectory to missiles and guns. When pilots receive a fire-control radar warning, they essentially have to act as if we are attacking them, leading to evasive manoeuvres that can escalate what should be a normal intercept into a crisis.
Japanese officials described the lock-ons as the first time they were aware of Chinese and Japanese combat planes locking fire-control radar on each other, although a Chinese navy frigate had previously locked similar weapons-control radar on a Japanese destroyer in the East China Sea in 2013. Beijing has dismissed Tokyo’s version of events, claiming that Japanese planes approached and “interfered with” its carrier exercises east of the Miyako Strait and arguing that Chinese troops operated legally and safely.
Old arguments over fire-control radar reverberate in 2025
The incident in 2013, which saw a Chinese warship guide its fire-control radar onto the Maritime Self-Defence Force destroyer Yuudachi near the disputed Senkaku/Diaoyu Islands, prompted strong Japanese protests and warnings from friendly nations about the risk of miscalculation, as reported by Reuters in 2013. Tension roared back in 2016 when Beijing said Japanese fighters had trained their own fire-control radar on Chinese planes above the East China Sea, part of an aerial spat that USNI News covered, showing how each side now cites past incidents to bolster its stance.
Since then, such close intercepts and aggressive manoeuvres have become more common as Chinese naval and air patrols increase around Japan’s southwestern islands and across the broader Pacific. Chinese aircraft also conducted a dangerous close call with a Self-Defence Force patrol plane near Okinawa earlier this year, Japanese officials said, and the Defence Ministry has reported an increase in JASDF fighter scrambles to intercept airborne Chinese bombers and fighters skirting Japanese airspace.
Taiwan tension and allies’ response
The latest fire-control radar episode comes weeks after the day Takaichi warned that Japan could use military force if a Chinese attack on Taiwan posed an existential threat to Japan, a comment that was rebuked by Beijing and led to a new surge of Chinese ships and aircraft off Japan. Tokyo described Sunday’s protest as a broader effort to prevent “unilateral attempts to change the status quo by force” without provoking further escalation.
Australia, whose defence minister, Richard Marles, was in Tokyo for talks at the time of the news, supported Japan’s call for safe, professional behaviour by regional militaries while mindful of its own need to manage relations with Beijing, according to a report by The Associated Press. With the United States having large air and naval forces in Okinawa and across Japan, diplomats and military commanders warn that the mix of political friction, high-pressure operations, and the provocative use of fire-control radar in congested skies leaves little room for error.
