The J-20 stealth fighter is not equipped with a Luneburg lens, a radar reflector used to make a stealth aircraft visible to others in training or non-combat flights

J-20 stealth fighter jets affiliated with multiple Chinese People's Liberation Army (PLA) Air Force units started the year with intensive mock combat training sessions against other types of warplanes including the J-11B and the J-16, with many details revealed by official media reports displaying that China's most advanced aircraft has a high level of combat readiness, experts said on Sunday.

A brigade with the PLA Northern Theatre Command Air Force organized an aerial confrontation exercise on the first training day of 2022, with the two sides involved in the mock combat both having ace pilots that have won the Golden Helmet - the most realistic combat-oriented air battle contest, China Central Television (CCTV) reported over the weekend.

Two J-20 stealth fighter jets were pitted against an unknown number of non-J-20 warplanes, including a J-11B fighter jet, the report shows, which also gives an indication that a J-20 carried a Luneburg lens, a radar reflector that makes stealth aircraft visible to others in training.

Under a complex electromagnetic environment, the two J-20s had a fierce confrontation with their opponents. In a round of intense engagement, a J-20 and an opposing aircraft had each other locked on head-to-head after a series of tactical manoeuvres, and both pilots opened fire almost at the same time, which was also when the two both performed high-G manoeuvres that saw them evading the mock attack, CCTV reported.

The J-20 side eventually emerged victorious thanks to the pilots' smart use of the aircraft's advantages, the report said.

This brigade received delivery of the J-20s only last year, as the second ace force in the PLA Air Force to be equipped with the country's most advanced fighter jet, according to media reports.

The Northern Theatre Command brigade is not the only unit to hold mock battles with the J-20, as another Air Force training base also held similar drills recently.

Marking the start of 2022, multiple types of aircraft including J-20 and J-16 fighter jets took off in the drills and conducted drills including aerial mock combat and live-fire attacks against ground targets, CCTV said in a separate report on Thursday.

Two J-20s faced two J-16s in a mock combat, the report revealed, without disclosing the result of the match. The report also shows that a J-20 had a Luneburg lens on it.

"We aimed at demands in real combat and trained at the highest level of the training program," Wang Zhen, a regimental commander at the training base, was quoted by the report as saying.

Liu Jinrui, commander of the training base, said in the report that the training explored and verified new approaches to generate combat capabilities.

The intensive mock combat sessions across different PLA units display the J-20s' high level of combat readiness, a Chinese military expert who requested anonymity told the Global Times on Sunday.

Using Luneburg lenses means the J-20s gave up their stealth advantages to focus on training on other capabilities, the expert said, noting that in real combat, it is also possible that a powerful enemy could find a way to detect stealth aircraft, so such training is practical.

Other types of aircraft could also get chances to practice against advanced fighter jets like the J-20 and figure out ways to deal with opponents stronger than themselves, the expert said.