Second Lieutenant Walls was the pilot of a F-84E Thunderjet fighter with the 7th Fighter-Bomber Squadron, 49th Fighter-Bomber Group. On 3 March 1952, while on a combat mission, his aircraft received a direct hit by anti-aircraft fire and augured into the ground. His remains were not recovered. His name is inscribed on the Courts of the Missing at the Honolulu Memorial.

For his leadership and valor, Second Lieutenant Walls was awarded the Distinguished Flying Cross, 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.