Aviation Ordnanceman Airman Macklin was a crew member of a PBM-5S Catalina patrol bomber with Patrol Squadron 47. On 26 December 1952, while participating anti-submarine patrol over Korean waters, his aircraft engine malfunctioned and crashed, killing 10 of the 14 seamen on board. His remains were not recovered. His name is inscribed on the Courts of the Missing at the Honolulu Memorial.

Macklin was awarded 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.