Donoghue served in the Navy from 1942 to 1946 and the Navy Reserve from 1947 to 1960. He was an Aeronautical Engineer who served aboard several aircraft carriers as an Engine Ring Officer for a Fighter Squadron and as a Structural Engineer. He served aboard the U.S.S. Intrepid, U.S.S. Hancock, and with CASU-5-NAS San Diego, VF-36-FPO, San Francisco, VF-18-FPO, San Francisco, and EuAer, Navy Dept., Washington DC.