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.