The People's Liberation Army Air Force has commissioned the YY-20, a large aerial refueling aircraft, which observers said will extensively enhance the service's operational capability.

Senior Colonel Shen Jinke, spokesman for the PLA Air Force, said at a news conference on Sunday in Beijing that the YY-20 tanker aircraft recently carried out aerial refueling exercises with the J-16 strike fighter above the sea, and the operations helped to improve combat training.

The tanker is a variant of China's Y-20 strategic transport plane. Like the Y-20, the new tanker is a product of the State-owned defense contractor Aviation Industry Corp of China.

As China's latest aerial refueling hardware, the YY-20 can effectively strengthen the PLA Air Force's long-range mobile capability and, like the Y-20, can also undertake personnel and cargo transportation tasks, Shen said.

This was the first time that the Chinese military confirmed the existence of the YY-20, though the plane has already appeared in information published by Taiwan defense authorities that claimed the YY-20 has taken part in at least two patrol operations over the Taiwan Straits.

Before the YY-20, the PLA Air Force deployed a small number of HY-6 tankers, refitted from the decades-old H-6 bomber aircraft. It also operates several Ilyushin Il-78 aerial refueling jets bought from Russia.

However, those planes are far from enough to meet the demands from the PLA Air Force and also are not good enough to fit into modern air operations, highlighting the need for a new, domestically developed model that can be deployed on a large scale.

Wang Ya'nan, editor-in-chief of Aerospace Knowledge magazine, said a large aerial refueling plane is as important as a stealth strategic bomber to the PLA Air Force, because it will extensively extend the flight radius of its fighter jets, bombers and support aircraft such as early-warning and electronic warfare planes.

"The YY-20 can enable our combat planes to stay longer in their target airspace, giving more flexibility and options to mission commanders. With the new tanker, fighter jets, bombers and support planes can also carry more weapons and equipment," he said.

Wu Peixin, an aviation industry observer in Beijing, said the YY-20's service means that China has become the fourth country in the world capable of building large tanker aircraft, following the United States, Russia and France.

"In the past, the shortage of aerial refueling platforms had been an outstanding weakness of the PLA Air Force for a long time, and it hindered the force from conducting large joint operations," Wu said.

He also said the plane can amplify the PLA Air Force's fighting prowess over high seas, adding that it is turning the service into a world-class force with long-distance strike capability.

In another development, Shen said at Sunday's news conference that multiple types of the PLA Air Force's aircraft have flown around Taiwan, and their pilots have honed their skills to safeguard the country's sovereignty and territorial integrity.

The spokesman also said that the PLA Air Force has organized many long-range patrols and exercises to improve its combat power and will continue to do so.