Lieutenant Thomas was the pilot of a F4U-4 Corsair fighter with Fighter Squadron 114 (884) aboard the carrier USS Boxer (CV-21). On 18 April 1951, while attacking targets near Hamhung, North Korea, his aircraft hit a power line and exploded. His remains were not recovered. His name is inscribed on the Courts of the Missing at the Honolulu Memorial.

For his leadership and valor, Lieutenant Thomas was awarded the Distinguished Flying Cross with 2 Gold Stars, the Air Medal with 3 Gold Stars, the Purple Heart, the Combat Action Ribbon, 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.