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 U.S. Pacific Air Forces chief.

Gen. 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.