Civil Air Transport (CAT) (IATA: CT, ICAO: CAT, Call sign: Mandarin) was a Nationalist Chinese airline, later owned by the CIA, that supported United States covert operations throughout East and Southeast Asia. During the Cold War, missions consisted in assistance to Free World allies according to the Mutual Defense Assistance Act of 1949.

CAT was created by Claire Chennault and Whiting Willauer in 1946 as Chinese National Relief and Rehabilitation Administration (CNRRA) Air Transport. Using surplus World War II aircraft such as the C-47 Dakota and the C-46 Commando, CAT airlifted supplies and food into war-ravaged China. It was soon pressed into service to support Chiang Kai-shek and his Kuomintang forces in the civil war between them and the communists under Mao Zedong. Many of its first pilots were veterans of Chennault's World War II combat groups, popularly known as Flying Tigers. (Other of Chennault's veterans went on to form another air transport company, the Flying Tiger Line. This was a completely separate operation from Civil Air Transport and the follow-on Air America.)

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