Technical Sergeant Underwood was a crew member of a F4U Corsair fighter with the Marine Fighter Squadron 214, Marine Air Group 12, 1st Marine Air Wing. He died in Korea from other causes on 19 September 1950.

Underwood was awarded 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.