Xue Lun was named head of the first Chinese astronaut group, Unit 714, in 1971. He was purged after being accused of involvement in Lin Biao's coup d'etat against Mao Zedong. The group was dissolved soon thereafter. Prior to that assignment he was Commander of the 24th Training Division. Xue began service as an air force pilot in 1951, seeing operations against the Americans in Korea. He was later ordered by Vice Minister for Aviation Yu Zhenwu to conduct test flights of aircraft stall and spinning conditions that were contributing to the high accident rate within the Air Force. Revisions to training were incorporated as a result of these tests, which substantially lowered the accident rate.