December 17, 2021: The Y20U aerial refueling version of the new Chinese jet transport, the Y20, carried out its first operational flight outside China on November 28th. A single Y20U accompanied five H6 heavy bombers, two KJ500 AWACS (aerial warning and control) a Y9 ECM (electronic countermeasures) aircraft and 18 fighters (six J10s, four J-11s and eight J-16s). The flight was more political than practical since the mission was to violate the Taiwanese ADIZ (Air Defense Identification Zone). Any aircraft that enter the ADIZ and refuse to identify themselves, must be checked out by fighters. In this case Taiwan sent up some fighters to confirm what ground-based sensors had indicated. Taiwan does not send a lot of fighters aloft for ADIZ violations because there are so many of them by China and that consumes over five percent of the defense budget each year. This is justified as training for fighter pilots, especially those assigned to squadrons that would take on hostile aircraft in wartime. The Y20U did not refuel any of the aircraft it accompanied and the flight was short, around Taiwan and then back to China.

In 2019 a Y20U was spotted flying inside China with its aerial refueling equipment, which appears to be Russian made UPAZ-1M refueling pods. This tanker version apparently flew for the first time at the end of 2018. It appears to be equipped with UPAZ-1M refueling pods under each wing. Russian tankers also attach a third one of these pods to the rear fuselage of the aircraft. The Y-20U will probably carry up to 80,000 liters (60 tons) of fuel, as well as cargo or passengers. Up to 3,000 liters a minute can be transferred from each of these pods using the hose and drogue method. The Y-20U will have a crew of six, to include three refueling operators if three pods are installed. China currently has about 24 refueling aircraft, all but three them H-6 bombers converted to tankers as well as three Russian IL-78 tankers, which has the same performance and refueling capacity as the Y20U. The H-6 has a shorter range and carries only about 30 tons of fuel. China needs the Y20U to accompany long- range flights of fighters and bombers against distant targets like the American bases on Guam island. The H6 bombers carry air-to-surface missiles. Closer to China, the Y20U can keep more fighters in the air longer for air defense or attacks on Taiwan.

In early 2013 the Y-20 flew for the first time and it entered service with the Chinese Air Force in 2016 as the Y-20A. So far about 30 have been built, including eight prototypes and at least four Y20Us. The Y-20 was a major milestone because for the first time China had developed a large military jet transport. The Y-20 aircraft resembles the American C-17 and has a max weight of 180 tons and a max payload of 66 tons. The current Y-20 includes many characteristics of the 195-ton Il-76, a Russian heavy transport that can carry up to 50 tons and that the Chinese have been using for decades. The Y-20 can travel 4,500 kilometers with max payload, 7,800 kilometers with 40 tons and at least 10,000 kilometers carrying just passengers or 130 paratroopers. Max speed is 900 kilometers an hour and cruise speed is about 700 kilometers an hour. Max altitude is 13 kilometers (42,000 feet). There is a crew of three; two pilots and a loadmaster. The aircraft is all Chinese made except for the four engines, which are Russian. The Y-20 has been tested with similar, but less effective, Chinese WS-18 engines. China expects to have the superior (to the Russian engines) WS-20 engine ready in a few years and these will replace the Russian ones in new aircraft and in existing aircraft as engine replacement is required. The WS-20 engine consumes less fuel and provides more lift than the Russian D-30KP now used. China expects to eventually upgrade the Y-20 to C-17 performance levels. Currently, 400 J-20s are planned, most of them for cargo.

In 2013 the two existing Y-20 prototypes underwent ground taxi tests two weeks before the first flight. China proudly described the construction of the Y-20, using specially developed composite materials for many components. These strong and lightweight materials were formerly only available from Western suppliers. China expected most of the Y-20 components to come from China and so far, except for the engines, that is the case.

The similar American C-17 entered service in 1996, two years after its first flight, and each C-17 has a useful life of 30,000 flight hours. China has yet to reveal similar performance data for the Y-20. The 290-ton C-17 can carry up to 100 tons (including one M-1 tank) anywhere in the world because of in-air refueling. The C-17 costs about $250 million each while the Y-20 goes for less than $200 million. There are several export customers for the C-17, including Britain, Australia, India, Canada, Qatar and the UAE. The U.S. Air Force operates 203. China wants to stop using Russian IL-76 heavy transports and become the largest producer, and exporter, of these heavy transports in the world. In addition to the tanker version, China is also planning to build its next-generation AWACS (air control) aircraft around the Y-20.

Up until 2005, China was content to buy Russian heavy transports. In 2005 China placed a $1.5 billion order for 38 Il-76 transport planes and Il-78s (tanker versions of the Il-76). But in 2006 China canceled the deal when Russia tried to up the price 27 percent (to $50 million per aircraft). China went looking elsewhere, including urging its domestic aircraft manufacturers to come up with something. That process eventually led to the Y-20, but in the meantime, China needed some more jet-powered military transports. China urged domestic manufacturers to come up with something and by 2011 an acceptable design was presented. Two years later it flew and three years after that it was in service. China did not buy any more Il-76s although it continued to buy the same engines that power the Il-76. Already the Y-20 is competing with the Il-76 and C-17 for export sales.