First Lieutenant Bull was the pilot of a F-80C Shooting Star Fighter-Interceptor with the 25th Fighter-Interceptor Squadron, 51st Fighter-Interceptor Group. On 18 March 1951, while on a combat mission, his aircraft received a direct hit by anti-aircraft fire, the bombs toggled, and the aircraft inverted and crashed. He was listed as Missing in Action and was presumed dead on 10 February 1952. His name is inscribed on the Courts of the Missing at the Honolulu Memorial.

For his leadership and valor, First Lieutenant Bull was awarded the Distinguished Flying Cross, the Air Medal with 3 Oak Leaf Clusters, the Purple Heart, the Korean Service Medal, the United Nations Service Medal, the National Defense Service Medal, the Korean Presidential Unit Citation and the Republic of Korea War Service Medal.