 Led by Claire Lee Chennault, their early combat success of 300 kills against a loss of 12 of their newly introduced shark painted P-40 fighters heavily armed with 6X50 caliber machine guns and very fast diving speeds earned them wide recognition at a time when the Chinese Air Force and Allies in the Pacific and SE Asia were suffering heavy losses, and soon afterwards their "boom and zoom" high-speed hit-and-run dissimilar air combat tactics would be adopted by the United States Army Air Forces.The Sino-American Cooperative Organization was an organization created by the SACO Treaty signed by the Republic of China and the United States of America in 1942 that established a mutual intelligence gathering entity in China between the respective nations against Japan.It operated in China jointly along with the Office of Strategic Services (OSS), America's first intelligence agency and forerunner of the CIA while also serving as joint training program between the two nations.