Flying Tigers was the nickname of the 1st American Volunteer Group (AVG) that operated within the Chinese Air Force in 1941 and 1942. In essence, the group was a private military contractor, although they have also been called mercenaries. Its members were former United States Army (USAAF), Navy (USN), and Marine Corps (USMC) pilots and ground crew, recruited under Presidential approval and commanded by Claire Chennault. The group consisted of three fighter squadrons that trained in Burma before the American entry into World War II with the intention of defending China against Japanese forces.

The Tigers' shark-faced fighters remain among the most recognizable of any individual combat aircraft of World War II, and they demonstrated innovative tactical victories when the news in the U.S. was filled with little more than stories of defeat at the hands of the Japanese forces.

The group first saw combat on 20 December 1941, 12 days after Pearl Harbor (local time). It achieved notable success during the lowest period of the war for U.S. and Allied Forces, giving hope to Americans that they would eventually succeed against the Japanese. The Tigers were credited with destroying almost 300 aircraft while losing only 14 pilots on combat missions. In July 1942, the AVG was replaced by the U.S. Army 23rd Fighter Group, which was later absorbed into the U.S. 14th Air Force with General Chennault as commander. The 23rd Group went on to achieve similar combat success, while retaining the nose art and nickname of the volunteer unit.

Chennault fighter doctrine
Chennault preached a radically different approach to air combat based on his study of Japanese tactics and equipment, his observation of the tactics used by Russian pilots in China, and his judgment of the strengths and weaknesses of his own aircraft and pilots. The actual average strength of the AVG was never more than 62 combat-ready pilots and fighters. Although he faced serious obstacles since many AVG pilots were inexperienced and a few quit at the first opportunity, however, Chennault made a virtue out of these disadvantages, shifting unsuitable pilots to staff jobs and always ensuring that he had a squadron or two in reserve.

His doctrine called for pilots to take on enemy aircraft in teams from an altitude advantage, since their aircraft were not as maneuverable or as numerous as the Japanese fighters they would encounter. He prohibited his pilots from entering into a turning fight with the nimble Japanese fighters, telling them to execute a diving or slashing attack and to dive away to set up for another attack. This "dive-and-zoom" technique was contrary to what the men had learned in U.S. service as well as what the Royal Air Force (RAF) pilots in Burma had been taught; it had been used successfully, however, by Russian units serving with the Chinese Air Force.

The P-40's good qualities included pilot armor, self-sealing fuel tanks, sturdy construction, heavy armament (two 50-cal. and four 30-cal. machine guns), and a higher diving speed than most Japanese aircraft – qualities that could be used to advantage in accordance with Chennault's combat tactics. Chennault created an early warning network of spotters that would give his fighters time to take off and climb to a superior altitude where this tactic could be executed.

AVG fighter aircraft were painted with a large shark face on the front of the aircraft. This was done after pilots saw a photograph of No. 112 Squadron RAF in North Africa sporting a fierce shark mouth, which in turn had adopted the shark motif from German pilots flying Messerschmitt Bf-110 fighters in Crete. About the same time, the AVG was dubbed "The Flying Tigers" by their Washington support group, called China Defense Supplies.

Throughout the war Chennault was engaged in a bitter dispute with the American ground commander, General Joseph Stilwell. Chennault asserted that the Fourteenth Air Force, operating out of bases in China, could attack Japanese forces in concert with Nationalist Chinese troops. In contrast, Stilwell insisted that air assets be diverted to his command for an offensive to force the opening of a ground supply route through northern Burma to China. This route would provide supplies and new equipment for a greatly expanded Nationalist force of twenty to thirty modernized divisions. Chiang Kai-shek favored Chennault's plans, as he was suspicious of British colonial interests in Burma, and because he was not prepared to begin major offensive operations against the Japanese. He was also concerned about alliances with semi-independent generals supporting the Nationalist government, and was concerned that a major loss of military forces would enable his Communist Chinese adversaries to gain the upper hand.

Good weather in November 1943 found the Japanese Army air forces ready to challenge Allied forces once again and they began both night and day raids on Calcutta and the Hump bases while their fighters struck back vigorously against any Allied air intrusions over Burma.

In 1944, Japanese ground forces advanced and seized Chennault's forward bases, though they were severely mauled by the Fourteenth's air force at the Salween River and other chokepoints. Slowly, however, the greater numbers and greater skill of the Allied air forces began to assert themselves. By mid-1944, Major General George E. Stratemeyer's Eastern Air Command completely dominated the skies over Burma; this superiority was never to be relinquished.

By mid-1944, logistical support reaching India and China via the Hump finally reached levels permitting the long-awaited Allied offensive into northern Burma. In formulating their strategy for defending Burma in 1944, the Japanese failed to appreciate Allied air capabilities. The Japanese Army did not succeed in invading India because it had been unable to establish and maintain the long suuply lines necessary to maintain their troops. The Allies did not depend upon such supply lines, either to support their troops, or to maintain their jungle penetration offensives. Instead, hundreds of Allied transport planes brought food, ammunition, and all manner of supplies directly to Allied troops. If there were no nearby airfields where they could land, the airmen dropped these supplies into rice paddy or jungle clearings. Anything that might break was dropped by parachute; everything else was free-dropped. Thus, the Allies' only supply line came through the air, which they controlled completely. And, having driven Japanese combat planes from the skies, the Allies had no worries about air strikes against their bases in India.

Chennault had long argued for expansion of the airlift, doubting that any ground supply network through Burma could ever provide the tonnage needed to re-equip Chiang's divisions. However, work on the road, known as the Ledo Road, continued throughout 1944, though it was not actually completed until January 1945. Training of the new Chinese divisions commenced; however, estimates of monthly tonnage (65,000 per month) over the road were never achieved. By the time Nationalist armies began to receive large amounts of supplies via the Ledo Road, the war had ended. Instead, the airlift continued to expand until the end of the war, after delivering 650,000 tons of supplies, gasoline, and military equipment.

The Flying Tigers are a business enterprise to some, and a life's worth of private research to others. They are remembered both for when they came and what they did. In the case of transporters who are mistakenly identified as ‘Flying Tigers,' some are even remembered for things they never did.
For most Chinese people, they remember the war as a new vocabulary:

Flying Tigers, Chennault, shark-headed planes, American-Chinese cooperation, volunteerism, love stories, American products, friendship, mutual assistance.