Photo taken in June, 2016 shows two Y-20 planes, China's homegrown large transport aircraft, taxiing to airport runway. Two Y-20 planes officially joined the People's Liberation Army Air Force on July 6, 2016. (Xinhua/Xing Guangli)

The development of the aerial tanker variant of China's domestically developed Y-20 large cargo plane is apparently entering the final stages, as a recent photo captured what seems to be a Y-20 tanker variant conducting aerial refueling for a J-20 stealth fighter jet, media reports said.

Combinations of the Y-20 aerial tanker with the likes of the J-20 fighter jet and H-6N strategic bomber can significantly expand the operational range of the Chinese People's Liberation Army (PLA) Air Force and defend China against military aggression from West Pacific, analysts said on Tuesday.

The photo, which circulated on social media platforms over the past few days, although its authenticity hasn't been verified, shows a Y-20 dragging a refueling hose in the air, with a J-20 approaching from the rear in a move that looks similar to aerial refueling, Ordnance Industry Science Technology, a defense magazine based in Xi'an, Northwest China's Shaanxi Province, reported on Monday.

If the photo is verified, it would be the first sighting of a Y-20 tanker variant conducting aerial refueling for a J-20 fighter jet.

Judging from the photo, the Y-20 aerial tanker was using a hose-and-drogue refueling system, while the J-20 was using a fuel-receiving probe, Fu Qianshao, a Chinese military aviation expert, told the Global Times on Tuesday.

Now that the Y-20 tanker has made it to the sky and tested its capabilities with the J-20, this type of aerial tanker variant is likely technically mature and can enter test service, Fu said.

In February, Teng Hui, commander of an Air Force aviation regiment of the PLA Western Theater Command and Y-20 pilot, said on China Central Television that "The Y-20 cargo plane has variants like the Y-20 aerial tanker and Y-20 aerial early warning aircraft. I believe that people will see our Y-20 aerial tanker debut on the battlefield in the not too distant future."

It is widely expected that the tanker variant of the Y-20 will work together with and eventually replace the PLA's very few imported Il-78 tankers and the domestically developed but less capable HU-6.

Upon receiving aerial refueling from the Y-20 aerial tanker, the J-20 can extend its range to more than 8,000 kilometers and combat radius to more than 3,000 kilometers, Ordnance Industry Science Technology magazine said, noting that with several refuels, the J-20 can travel more than 10,000 kilometers for intercontinental flights.

The combination of the Y-20 tanker variant and the J-20 can cover the entire first and second island chains, becoming the PLA Air Force's sharpest spear in both attack and defense, the magazine said.

Fu said that the Y-20 tanker version can refuel not only tactical warplanes like the J-20, but also strategic ones like the aerial refuel-capable variant of the H-6 bomber.

Making its first public debut at the National Day parade in Beijing on October 1, 2019, the PLA Air Force's H-6N bomber can receive aerial refueling. Media reports suggest it can carry weapons including air-launched ballistic missiles and hypersonic missiles.