First Lieutenant Foster was a crew member on a B-29A Superfortress Bomber with the 28th Bomber Squadron, 19th Bomber Group. On 30 December 1952, after delivering bombs on the enemy near Taesong-Dong, North Korea, the aircraft was attacked by MiG fighters, and the crew was ordered to bail out about 25 miles north of Pyongyang. 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.

Foster was awarded the Air Medal, 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.