Private First Class Flynn was a member of the 23rd Infantry Regiment, 2nd Infantry Division. He was seriously wounded by the enemy in North Korea on 18 November 1950 and returned to duty on 6 February 1951. He was Killed in Action while fighting the enemy in South Korea on 9 March 1951.

Flynn was awarded the Purple Heart with Oak Leaf Cluster, the Combat Infantryman Badge, 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.