Captain Grisham was the pilot of a F-51D Mustang night fighter with the 20th Weather Squadron, 18th Fighter Bomber Group. On 3 September 1950, he encountered bad weather over Pusan and, after being seen near Tsushima, contact was lost. He was listed as Missing in Action and was presumed dead on 31 December 1953. His name is inscribed on the Courts of the Missing at the Honolulu Memorial.

For his leadership and valor, Captain Grisham was awarded the Distinguished Flying Cross, the Bronze Star, 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.