CGRONONE consisted of 26 82’ Patrol Boats operating with Operation Market Time from 30 July 1965. The WPBs were designed to operate offshore in heavy weather. The Navy Swift was not. Since the WPB remained on station in weather that forced the Swift home, TF 115 decided the boats would shift patrol areas seasonally, the WPBs would follow the monsoons and the Swifts would follow the sunshine. This decision was not popular with Coast Guard crews. When not on patrol, the cutters nested alongside LSTs converted to tenders. The mission was to board and search as many vessels as possible. As with most patrol duty, it consisted of hours of boredom punctuated by moments of stark terror.
On its fist night of patrol, Point Orient took mortar and machine gun fire near the 17th Parallel. White cutters were easy targets in moonlight. On 21 September, all boats were painted gray. The first action came on 19 September. Point Glover and Point Marone were both fired on while attempting to board different junks. Both cutters returned fire and sank the junks.
On 10 May 1966, Point Grey shadowed a 110-foot trawler near Ca Mau. After observing what appeared to be signal fires on the beach, Point Grey hailed the trawler, but received no response. The trawler ran aground. When Point Grey crewmen attempted a boarding, they were met with heavy machine gun and mortar fire from the beach. Point Cypress joined the battle. During the fight, the trawler exploded. Navy salvage teams recovered the largest single cache of weapons and supplies intercepted during the war. Three Coastguardsmen were wounded in the action.
On 11 August 1966, Point Welcome, patrolling near the DMZ, was attacked by U.S. Air Force aircraft. The cutter’s CO and another crewman were killed. The XO, two other crewmen, a Vietnamese interpreter, and a freelance photographer were wounded. BMC Richard Patterson was awarded a Bronze Star for saving the cutter and assisting the injured crewmen.
In September, Point League responded to an SOS from SS Dragonfly.
In October, Point Comfort provided NGFS to break up a VC attack on an Army Special Forces camp.
In May 1967, Point Ellis rescued the crew of a survey boat that had been hit by fire form the beach and Point Kennedy rescued a sailor who had fallen overboard from USS Princeton.
The largest single naval engagement of the war came on 29 February 1968. Four steel-hulled trawlers attempted to deliver supplies to forces engaged in the Tet Offensive. The first trawler was sighted and challenged by USCGC Androscoggin near Da Nang. A firefight broke out and Point Welcome and a Swift closed in to deliver supporting fire. At 0230 1 March, the trawler beached and exploded. USCGC Winona, Point Grace, Point Marone, Point Hudson and two Swifts destroyed a second trawler off the Ca Mau peninsula. Swifts sighted and destroyed a third trawler Nha Trang. USCGC Minnetonka sighted the fourth trawler as it crossed into South Vietnamese waters and challenged it. The trawler tuned about and sped north.
Point Banks rescued nine soldiers trapped by VC. Point White and Point Cypress combined to rescue three Swifts that had grounded. Point White crewmen repaired an evaporator that had been declared unserviceable and gave Ha Tien their first fresh water in over a year. In early 1970 over 300 vessels were boarded.
January 1969 began a massive stand down and turn over of equipment to South Vietnamese forces. VNN officers reported aboard the cutters to be assume command. On 16 May 1969, Point Garnet and Point League were turned over. On 15 August 1970, Point Marone and Point Cypress, were turned over. CGRONONE was disestablished.