The American Volunteer Groups were volunteer air units organized by the United States government to aid the Nationalist government of China against Japan in the Second Sino-Japanese War. The only unit to actually see combat was the 1st AVG, popularly known as the Flying Tigers.
Claire Lee Chennault (1893–1958) was instrumental in the implementation of the AVGs
Douglas A-20 Havoc of the United States Army Air Forces
The Lockheed Hudson (seen in RAF use) was an American-built light bomber and coastal reconnaissance aircraft
The First American Volunteer Group (AVG) of the Republic of China Air Force, nicknamed the Flying Tigers, was formed to help oppose the Japanese invasion of China. Operating in 1941–1942, it was composed of pilots from the United States Army Air Corps (USAAC), Navy (USN), and Marine Corps (USMC), and was commanded by Claire Lee Chennault. Their Curtiss P-40B Warhawk aircraft, marked with Chinese colors, flew under American control. Recruited under President Franklin Roosevelt's authority before Pearl Harbor, their mission was to bomb Japan and defend the Republic of China, but many delays meant the AVG first flew in combat after the US and Japan declared war.
Flying Tigers personnel
Chennault in his Kunming office, May 1942. He wears a US Army brigadier general's star on his left shoulder but Chinese insignia otherwise.
3rd Squadron Hell's Angels, Flying Tigers, over China, photographed in 1942 by AVG pilot Robert T. Smith
P-40 Warhawk painted with Flying Tigers shark face at the National Museum of the United States Air Force