Between the hours of 1800-1900, 12 April 1969, at a well-camouflaged sector along the narrow Duong Keo, southernmost in South Vietnam’s vast system of navigable waterways, U.S. Navy PCF’s (“swiftboats”) then supporting Vietnamese Marine river operations under the aegis of SEALORDS incurred their most devastating and demoralizing setback to date. A well-planned and perfectly executed Viet Cong heavy weapons ambush inflicted heavy material damage to every swiftboat unit involved in the action and accounted for thirty-nine wounded in action, many seriously and requiring immediate medical evacuation. Vietnamese Marine casualties were of equal severity. One of the eight boats involved, PCF 43, was totally destroyed during the encounter. Its mangled, blackened carcass still rests on the ambush site. Her seventeen-member crew included ten members of an underwater demolition team, two were killed: Only three of the remaining fifteen escaped unscathed.[Source: By LTJG Peter N. Upton, UDT-13, article supplied by Steven L. Waterman, mwweb.com/ndc/SwiftBoats]

LTJG Peter N. Upton wrote: “Vietnamese mornings are singularly beautiful… However, this morning elegance passed quickly, when word was passed to UDT promulgating the modus operandi and logistics requirements for the upcoming three-day SEALORDS operation. It was about 1630 hours when UDT personnel scampered down the sagging cargo net, consummating the already bulking load. Rendezvous with the PCF units involved in the mission took place approximately one hour later, one thousand meters outside the gaping mouth of the Duong Keo, the watery path which would lead to the day’s assigned sweep area. Forty-three informed the command boat of her special cargo, then took her assigned station as the rear element of a stately file of eight units. Flak gear was donned and battle stations manned on the fantail as the boats proceeded to enter the foreboding jaws of this river, infamous for its demonstrated hostility to allied units who dared venture into her inner reaches. 

“On this day a Viet Cong heavy weapons company, consisting of approximately seventy-five hard-core guerrillas, was located in the area of the Duong Keo when they received warning through an elaborately contrived signal system that a swiftboat incursion was underway. A well fortified sector, up the river about five kilometers, interlaced with freshly built bunker, trench, and spider-hole emplacements and permeated with thick mangrove vegetation provided excellent cover for their weapons positions. Almost guaranteed of success, the enemy set up and waited.

“Discipline was perfect: the Viet Cong patiently awaited the greatest possible number of boats to be encompassed in their kill zone, then triggered the ambush with a claymore mine aimed at the lead boat. All hell broke loose as a murderous fusillade of rocket, recoilless rifle, machine gun, and small arms fire ensued. Every boat in the file received immediate hits and personnel casualties, but each roared back with her full arsenal of heavy .50 caliber machine guns. One by one the boats maneuvered upstream, out of enemy range. seeking open ground on which to set up an emergency medical evacuation station.

“PCF 43 never made it. Her position as last unit in the file, aggravated by her heavy load, combined to seal her doom. For, as the lead boats were exiting the kill zone and scrambling to safety upstream, the 43 was just arriving; as the first seven boats churned and leapt forward in violent reaction, throttles to the wall, the 43 succumbed to her bulk, falling farther and father behind until she was relatively alone, hopelessly alienated in the center of the kill zone. Viet Cong gunners then focused on the hapless intruder. Singled out for the kill, the 43 was ripped asunder, inexorably, and with lightning-like quickness: cascading water spouts signaled the near misses, though gunners at point-blank range will miss but once. One B-40 rocket found the fantail, instantly killing Doc Worthington. Hinson and Piper received frag wounds from the blast, Piper’s helmet perforated and blown off by a piece of shrapnel. AK-47 rounds raked the deck, one piercing Sandlin’s left leg, leaving a clean, though gaping wound. Another rocket exploded in the pilot house, mortally wounding the OIC and knocking the coxswain unconscious for precious seconds. Naked, without a guiding hand, 43 gesticulated wildly and careened into the north bank of the river, coming to her final, alien rest, high and dry amidst the mangrove foliage directly in front of the Viet Cong emplacements.