 Private Noonan completed recruit training with the 3rd Recruit Training Battalion, Marine Corps Recruit Depot Parris Island, South Carolina in April 1968, and was promoted to private first class on April 1, 1968.Transferred to the Marine Corps Base Camp Lejeune, North Carolina, he underwent individual combat training with the 1st Battalion, 1st Infantry Training Regiment.Ordered to the Republic of Vietnam in July 1968, he was assigned duty as mortar man with H&S Company, 2nd Battalion, 27th Marines, 1st Marine Division (Rein), FMF.