China’s military is closing the technology gap with the U.S., though the experience of America’s pilots still gives them an “unbelievably huge” edge, according to the Pacific Air Forces chief.

General Lori Robinson, in Singapore to attend the country’s air show, said she felt assured that Chinese pilots would act professionally in interactions with the U.S., citing a September agreement on rules of behavior. U.S. military pilots flying in the contested South China Sea have been warned over radio — sometimes repeatedly — by Chinese voices telling them to leave, while Japanese planes have been challenged in the neighboring East China Sea.

Since coming to power President Xi Jinping has prioritized modernizing the military with a focus on the navy and air force, as he seeks to project power outward and assert China’s claims to territory in the waters of the West Pacific. That has included greater spending on longer-range and higher-tech ships, planes and submarines, while the People’s Liberation Army has also focused on improving training and standards for its fighter pilots.

“The technology gap certainly is closing, there’s no denying that,” General Robinson said Tuesday in an interview. “The difference between that technology gap is the training that the United States air crew get. That training and the way our airmen work every single day, no matter what platform that they are on, and all the people that support those airmen to do that job. That edge is unbelievably huge.”

The Pentagon in a report released in May said China’s rapid military modernization “has the potential to reduce core U.S. military technological advantages.” China is “investing in capabilities designed to defeat adversary power projection and counter third-party —- including U.S. — intervention during a crisis or conflict,” according to the report.

Security analysts, however, have expressed doubt about the ability of China’s military pilots, noting a substantial portion of their training time was spent learning doctrine. That has raised concerns about them acting rashly when in proximity to planes from other nations.

Risky Intercepts

Shortly after she took her post in October 2014, Robinson said the U.S. was concerned Chinese jets may engage in further risky intercepts. A Chinese fighter flew within 20 feet of a U.S. P-8 Poseidon aircraft flying at more than 400 miles an hour near Hainan Island — China’s gateway to the South China Sea — in August of that year, an encounter the Pentagon described as “unsafe and unprofessional.”

The core of U.S.-China air tensions is what activities are permitted within a country’s 200-mile offshore exclusive economic zone, where coastal states have sovereign rights over marine resources. The U.S. says international law permits such flights, which have been a standard practice for decades. China objects, claiming such freedom is reserved for civilian aircraft.

China contests more than 80 percent of the South China Sea, putting it at odds with fellow claimants including Vietnam and the Philippines in a body of water that annually hosts $5 trillion in shipping. In the past two years, China has reclaimed more than 3,000 acres in the sea and is building military facilities there. It has made greater use of fishing and maritime surveillance boats to warn off other vessels in the area, blurring the lines between its navy and coast guard.

‘Excessive’ Claims

Last month the U.S. sent a warship into waters contested by China, Vietnam and Taiwan to challenge the “excessive” maritime claims of all three. It was the second time in less than six months the U.S. has challenged China with a freedom-of- navigation voyage. During the first operation by the USS Lassen, where it passed within 12 nautical miles of Subi Reef in the Spratly island chain, it was shadowed and warned by Chinese vessels.

Robinson said the U.S. would continue to fly in international airspace when required. “Any airplane that we need to go from point A to point B in international airspace will do that,” she said. “It’s not unusual for us to fly throughout the region and international airspace.”

When asked if the Chinese were still warning U.S. military planes away from the South China Sea, she said “they are talking, but mostly in my world from airplanes to airplanes everybody has acted professionally in accordance with the rules of behavior.”

Robinson, who joined the Air Force in 1982, is the first woman to have an Air Force command. She was previously vice commander of the air combat command at the Langley Air Force Base in Virginia before taking her current role in Hawaii, according to her Air Force biography.

She said any discussion of the U.S. having to cede ground to China in Asia as that country’s economic and military clout grows was hypothetical.

“What I depend upon today is our presence in the region, because our presence in the region provides that stability and capability in the region,” she said. “Our presence in the region allows for us to have partnerships throughout the region.”

Speaking also in Singapore, U.K. Defence Procurement Minister Philip Dunne said his country was watching “with great interest” an arbitration case brought before an international tribunal by the Philippines over its territorial dispute with China in the South China Sea.

“We are a maritime nation that has been dependent on open access to the oceans for trading going back several centuries,” Dunne said Tuesday in an interview. “So it’s absolutely ingrained in our being that we believe in freedom of navigation and believe that nations need to respect the rules of maritime law and generally international laws when they go about their business.”