First Lieutenant Chapman was a crew member of a B-29A Superfortress Bomber with the 325th Bomber Squadron, 92nd Bomber Group. On 13 July 1950, while making a bombing run at Oki-Gunto, bombs prematurely exploded and the aircraft crashed near Dogo Island, Japan. His remains were not recovered. His name is inscribed on the Courts of the Missing at the Honolulu Memorial.

For his leadership and valor, First Lieutenant Chapman was awarded the Distinguished Flying Cross, the Air Medal with Oak Leaf Cluster, the Purple Heart with Oak Leaf Cluster, 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.