The People’s Liberation Army Air Force (PLAAF) earlier said on its Weibo account that its reconnaissance aircraft, during a preplanned training exercise, took off from an air base in northern China and flew "to places they had never been before," Asia Times quoted Chinese agency Sina.
With Seoul still keeping silent, speculations have emerged that the Korean intelligence agencies may have failed to track the Chinese planes allegedly gathering information on the air drills, involving the Pentagon’s top-notch F-22 ace warplanes. This raises the question of which plane managed to come and go totally undetected.
"If that’s the case, then the only Chinese plane that was so stealthy that [it] could come and go totally undetected must be the J-20," one commentator said, as delivered by Asia Times.
"One or two J-20s may have flown with the group, which first headed to the East China Sea in a freedom-of-navigation patrol, but the fighter then turned northeast and pierced Seoul’s airspace, taking advantage of its cutting-edge stealth coating without triggering any alarm on Seoul’s radars."
Other sources suggest that there was a whole, though small, batch of J-20s, which just entered service this year, at the key air force base in Cangzhou, in the northern province of Hebei.