Upon his high school graduation, he was able to attend Illinois Institute of Technology with a Navy ROTC scholarship.

In 1955, he earned a degree in Physics and was commissioned an Ensign in the United States Navy upon his graduation.

At sea, he was the commander of Fighter Squadron 84, Carrier Air Wing Six, and a fleet oiler (the USS Truckee (AO-147)).

[3] On September 19, 1980, Libyan Air Force planes engaged in an unprecedented number of sorties in the vicinity of USS John F. Kennedy's Battle Group over international waters.

In 1988, Vice Admiral Diego E. Hernandez as Commander, Third Fleet, coordinated RIMPAC '88, a massive naval exercise which included more than 40 ships, approximately 200 aircraft and more than 50,000 sailors, airmen and Marines from the United States, Japan, Australia and Canada.