After receiving his NFO wings in June, 1980, Ensign McNamara was assigned to the World Famous Screwtops of VAW-123, making deployments to the Mediterranean and the Indian Ocean on the USS Saratoga and USS America. In 1980 he was assigned to Fleet Combat Direction Systems Support Activity in San Diego as a project office for E-2 software development. His next tour was as Anti-Air Warfare Officer on the staff of Commander, Cruiser-Destroyer Group FIVE on the USS Kitty Hawk, deploying yet again to the Indian Ocean and North Arabian Sea. This tour included a two-month SOCAL deployment on the USS New Jersey.
He returned to FCDSSA as a department head in the E-2C software development group. After refresher training at VAW-110, LCDR McNamara returned to the fleet as Safety Officer and Operations Officer for the VAW-117 Wallbangers, participating in the 1991 deployment that included Operation FIERY VIGIL (the Philippines Mount Pinatubo evacuation) and Operation DESERT STORM.
After a shore tour at AIRPAC, CDR McNamara deployed to the Arabian Gulf and Operation DESERT WATCH on the USS Constellation as the Command and Control and Air Operations Officer for Commander, Cruiser-Destroyer Group ONE. His final tour in the Navy was as department head for tactical data links at the Navy Center for Tactical Systems Interoperability.
Since retiring in 2000, he has worked in the defense industry, where he has specialized in advanced communications and airborne networking initiatives for the E-2C and other Navy and Joint Aircraft. During this time he had the privilege of working with CAPT Dan Allen and CAPT Pence Parsons.