Rear Adm. Pat Hannifin is a native of San Diego, California. He was commissioned in 1991 after earning a Bachelor of Science in Mechanical Engineering from the University of Pennsylvania and Master of Arts in International Relations from the University of San Diego. He is also a graduate of the Joint Advanced Warfighting School (JAWS) and the U.S. Air Force Test Pilot School.
Hannifin flew the F/A-18C Hornet with Strike Fighter Squadron 27 (VFA-27) “Royal Maces” from USS Independence, and then again with VFA-81 “Sunliners” for both department head and executive officer/commanding officer tours from USS George Washington and USS Nimitz, transitioning to F/A-18E Superhornets while in Command. He served as executive officer of USS Harry S. Truman (CVN-75); commanding officer of USS Arlington (LPD-24) and commanding officer of USS Ronald Reagan (CVN-76).