On August 15, 1964, the Naval Communications Station Philippines (NCSP) Det Alfa at Phu Bai, RVN was established. NCSP was established at that site circa 1957, and had existed in some form at Sangley Point before then.  Both the Marines and Navy had personnel assigned to Phu Bai prior to the official establishment of the Det and intercepts from Phu Bai were among those related to the Gulf of Tonkin incident that marked our serious involvement in Vietnam. 

Later on, NCSP would establish other detachments in Vietnam, two in Da Nang (Bravo and Delta), and one short-lived detachment (Charlie) in Saigon.

Naval Security Group personnel at NCSP Det Bravo were flying with VQ-1 during missions targeted against North Vietnam. Initially these missions were more strategic in nature, aimed at collecting Electronic Intelligence Order of Battle (EOB) information together with any supporting communications signatures. Once the air war started in early 1965, the mission fundamentally became one of direct support to the air strikes. Simply put, using the information detected onboard, VQ-1 aircraft (radio callsign DEEPSEA) broadcasted warnings of enemy air and SAM hostile intent to Navy and Air Force strikes over North Vietnam. We successfully did this until the end of the war. Though largely unheralded at the time, many of us have received a quiet “thank you” years afterward from a pilot who was warned in time by DEEPSEA.

By LCDR Robert E. Morrison, USN (ret.)