purchased in 1938 and became the personal aircraft of the American advisor to the Aviation Committee, Claire Chennault who oversaw training and lobbied for the procurement of American aircraft. The entry of the United States into the war with Japan at the end of 1941 led to the receipt of Lend-Lease equipment from the United States, including aircraft. American Lend-Lease aviation equipment had already begun to arrive in China as early as the middle of 1941, though that includes the first shipments before January 1942 which arrived under the guise of purchases. Including previously purchased American aircraft, US soon replaced USSR as the largest supplier for the Chinese Nationalist air force during the war (Including the Second Sino-Japanese War that actually broke out in 1931 when Japan invaded Manchuria). Retraining on American aircraft occurred for the most part in India. (Karachi and other cities), where Chinese pilots were sent both as groups and as entire units. As early as the end of 1941 Chinese pilots, mainly recently graduated from flight schools, began to be sent to the US for longer training and mastery of American aircraft. The first American P-43A fighters were received by the 4th Air Group (21st – 24th Squadrons) in March 1942. They retrained in Kunming, but for the new aircraft the pilots sequentially flew in small groups to India. On 24 April the deputy commander of the 24th Squadron, Wu Zhenhua, crashed on the flight to Kunming. On 12 May, Chen Lokun, the flight commander of the 24th Squadron was killed during a training flight, crashing into a tree during landing. In July for unclear reasons the P-43 of the 4th Air Group commander, Zheng Shaoyu, caught fire in the air and the pilot was killed. On 3 August 1942 during a training flight the deputy group commander Chen Sheng crashed. A similar series of crashes accompanied the mastery by the Chinese of almost every new machine. (It is notable that in Chinese sources the family names are given only of the perished commanders of various ranks, while the losses amongst the line pilots are hardly even noted.) Concluding their conversion to the P-43A in early August 1942, the group returned to Chengdu. In February 1943, preparing for transition to the new American air equipment, the Chinese transferred to India the primary training groups from their flight schools. Only training for reconnaissance and photography continued to