During the Korean War, the USSR sent "volunteer" fighter pilots to assist Chinese and North Korean pilots fight against the US. The Soviet pilots primarily served as instructor/advisors. On occasion, the Soviet pilots who undoubtedly had accumulated a wealth of experience fighting against the Germans less than ten years earlier were allowed to fly MiG-15s with Chinese markings against US F-86s. The American pilots could tell when an experienced (Soviet) pilot was flying. They were much harder to get an advantage over. The American pilots referred to these "experienced" pilots as Honchos. Some of these guys were probably aces who had seen abundant combat action fighting against FW-150s, Bf-109s and Me-110s.