In Spring 1965, air strikes over North Vietnam intensified, but monsoon conditions severely limited the navigation ability of the aircraft. The Air Force needed a reliable source of pin-point navigation in Vietnam. On 15 January 1966, CAPT Thomas Sargent, USCG, reported to MACTHAI with orders to procure land to construct a LORAN system in Southeast Asia to cover both North and South Vietnam. The Army colonel on duty told him there was no office space anywhere in the city and he would have to wait six months for a phone. Sargent dispatched CWO Baker Herbert to find office space and phones and went to brief senior MACTHAI officers. When he told them he intended to have a LORAN system up and running in eight months, they told him he was crazy. After the briefing, Herbert returned and handed Sargent the address of their new office and the phone number. When Sargent gave the information to MACTHAI, they started to believe he could build a system in eight months.
The chain became fully operational on 28 October 1966. The master station was in Satahip, 80 miles south-southeast of Bangkok on the Gulf of Tahiland. Slave I was in north-central Thailand, near Lampang. Slave II was on Con Son, a five-mile island 45 miles southeast of the delta. On 13 July 1969, the chain was extended by the addition of a chain based at Tan My. This station was manned by 35 Coastguardsmen, but also had a 35-man Air Force security police detachment and a three-man Marine NGFS liaison. A spring 1972 attack by North Vietnamese troops cut off the station and isolated it for about six months.
When the draw down came, Coast Guard personnel trained Vietnamese personnel on station operations. On 22 January 1973, LORSAT Con Son was disestablished and turned over. On 25 January, Tan My followed. On 3 October 1975, after South Vietnam had surrendered, Satahip and Lampang were disestablished.