Development of Chinese Nationalist air force (1937–1945)

The Republic of China Air Force (ROCAF) was formed by the Kuomintang after the establishment of the Aviation Ministry in 1920. As tensions mounted between China and Imperial Japan in the 1930s, a number of smaller Chinese warlord airforce men (including Guangdong Provincial Air Force) and equipment became integrated into the ROCAF in a centralized effort to counter Imperial Japanese military ambitions.

During the Second Sino-Japanese War (1937–1945), the ROCAF participated in attacks on Japanese warships on the eastern front and along the Yangtze river including interdiction and close-air support for the Battle of Shanghai in 1937. Initially, the Chinese frontline fighter aircraft were mainly Curtiss Hawk IIs and IIIs and Boeing P-26Cs. These engaged Japanese fighters in many major air battles beginning on 14th August 1937, when Imperial Japanese Navy warplanes raided Chienchiao airbase; "814" has thus become known as "Air Force Day". Chinese Boeing P-26/281 fighters engaged Japanese Mitsubishi A5M fighters in the world's first dogfight between all-metal monoplane fighters. A unique mission in April 1938 saw two Chinese Martin B-10 bombers fly a mission over Japan, but dropping only anti-war leaflets over the Japanese cities of Nagasaki and Saga. It was a war of attrition for the Chinese pilots, as many of their most experienced ace fighter pilots, such as Lieutenant Liu Tsui-Kang and Colonel Kao Chih-Hang, were lost. Six months into the war, which is considered the beginning of World War II in Asia, the Chinese Air Force inventory of frontline American Hawk IIs and IIIss and P-26Cs were superseded by faster and better armed Polikarpov I-15s and I-16s as support from the Soviet Union grew and American support faded.

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