Staff Sergeant Viveiros was the tail gunner of a B-26B Invader bomber with the 8th Bomber Squadron, 3rd Bomber Wing. On 25 March 1951, while on a night intruder mission as the aircraft approached the target, contact was lost. He was listed as Missing in Action and was presumed dead on 31 December 1953. His remains were not recovered. His name is inscribed on the Courts of the Missing at the Honolulu Memorial.

For his leadership and valor, Staff Sergeant Viveiros was awarded the Distinguished Flying Cross, the Air Medal with 4 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.