Japan's air force faces a 'relentless' burden, imposed by China

A Chinese H-6 bomber and Y-9 transport aircraft photographed by Japanese fighters on intercept missions.

Tokyo (CNN)Japanese fighter pilot Lt. Col. Takamichi Shirota says his country is under increasing pressure from the air. Analysts say it's a pressure faced by few other nations.

More than twice a day, Japanese fighter pilots hear a siren blare, bolt up from their ready-room seats, run to their jets, and scream aloft, ready to intercept a potentially unidentified incursion into Japanese airspace.
It happened to Japan's Air Self Defense Force (JASDF) 947 times in the last fiscal year ending in March. The culprit in most of those cases, warplanes from China's People's Liberation Army Air Force (PLAAF).
    And Shirota says the number of potential incursions is growing.
    Lt. Col. Takamichi Shirota.
    "The number of scrambles against airspace violations has been increasing rapidly over the past decade -- especially in the southwest air zone," said Shirota in an exclusive interview with CNN. "About 70% of the scrambles done by Japan's SDF annually are conducted in this area."
    That southwest area includes the Senkaku Islands -- known as the Diaoyu Islands in China -- a rocky, uninhabited group of islands under Japanese administration but claimed by China as its territory.
    It also includes Okinawa, home to the United States Air Force's Kadena Air Base, which touts itself as the "Keystone of the Pacific" and is a key US installation for flights over the contested waters of the South China Sea.