The Patrol Craft Fast (PCF), also known as the Swift Boat, were all-aluminum, long, shallow-draft vessels operated by the United States Navy, initially to patrol the coastal areas and later for work in the interior waterways as part of the brown-water navy to interdict Vietcong movement of arms and munitions, transport South Vietnamese forces and insert SEAL teams for counterinsurgency (COIN) operations during the Vietnam War.
Development
Conception
The Swift Boat was conceived in a Naval Advisory Group, Military Assistance Command, Vietnam (NAVADGRP MACV) staff study titled "Naval Craft Requirements in a Counter Insurgency Environment," published 1 February 1965. The study was positively received, and the Navy began to search for sources. Sewart Seacraft of Berwick, Louisiana (Swiftships' predecessor), built water taxis for companies operating oil rigs in the Gulf of Mexico, which appeared nearly ideal. The Navy bought their plans, and asked Sewart Seacraft to prepare modified drawings that included a gun tub, ammo lockers, bunks, and a small galley. The Navy used those enhanced plans to request bids from other boat builders. Sewart Seacraft was chosen to build the boats.
Mark I
The Swift Boats had welded aluminum hulls about long with beam, and draft of about five feet (1.5 m). They were powered by a pair of General Motors 12V71"N" Detroit marine diesel engines rated at each, with a design range from at to about at . The normal complement for a Swift Boat was six: an officer in charge (skipper), a boatswains mate, a radar/radioman (radarman), an engineer (engineman), and two gunners (quartermaster and gunner's mate). In 1969, the crew was supplemented with a Vietnamese trainee.
The first two PCFs were delivered to the Navy in late August 1965. The original water taxi design had been enhanced with two .50 caliber M2 Browning machine guns in a turret above the pilot house, an over-and-under .50-caliber machine gun – 81 mm mortar combination mounted on the rear deck, a mortar ammunition box on the stern, improved habitability equipment such as bunks, a refrigerator and freezer, and a sink. The 81 mm combination mortar mounted on the rear deck was not a gravity firing mortar as used by the Army and Marine Corps, in which the falling projectile's primer struck the fixed firing pin at the base of the mortar tube, but a unique lanyard firing weapon in which the projectile was still loaded into the muzzle. The gunner could "fire at will" by the use of the lanyard. The weapon had been tested in the 1950s and discarded as the U.S. Navy lost interest in the system. The United States Coast Guard maintained the gun/mortar system before the Navy incorporated it into the PCF program. Many boats also mounted a single M60 machine gun in the forward peak tank, just in front of the forward superstructure.
The original order for 50 boats was followed shortly by an additional order for 54 more Mark Is.
Mark II and Mark III In the latter half of 1967, 46 Mark II boats, with a modified deck house set further back from the bow. The newer boats also had round port holes (replacing larger sliding windows) in the aft superstructure. From 1969 through 1972, 33 Mark IIIs, which were a larger version of the Mark IIs, arrived in Vietnam.
Service
Most of the 193 PCFs built were used by the U.S. Navy in Vietnam and the two training bases in California. About 80 of the boats constructed were sold or given away to nations friendly to the United States. The original training base for Swift Boats was at Naval Amphibious Base Coronado.
In 1969, training was moved to Mare Island near San Pablo Bay, California, where it remained for the duration of the war. Though not a deep water boat, PCF training boats frequently transited from Mare Island, through the Golden Gate Bridge to cruise either north or south along the Pacific Ocean coastline. PCF-8 sank in a storm off Bodega Bay, California in December 1969. This was the only Swift Boat lost during training operations. No crewmen were lost in the event.
The most frequent training area for the Mare Island units was the marshland that forms the northern shoreline of San Francisco Bay. This area, now known as the Napa Sonoma Marshes State Wildlife Area, was also used by United States Navy Reserve unit PBRs) up until 1995, when Mare Island was scheduled for base closure.
Vietnam War service
The first Swift Boats arrived in South Vietnam in October 1965. The boats were initially used as coastal patrol craft in Operation Market Time, interdicting seaborne supplies on their way to the Viet Cong (VC) and People's Army of Vietnam (PAVN) forces in South Vietnam. However, the design's shallow draft and low freeboard limited their seaworthiness in open waters. These limitations, plus the difficulties being encountered in the interior waterways by the smaller, more lightly armed PBRs, led to the incorporation of Swifts to patrol the of rivers and canals of Vietnam's interior waterways.Symmes War on the Rivers p. 95 Swift Boats continued to operate along the Vietnamese coastal areas, but with the start of Admiral Elmo Zumwalt's "SEALORDS" riverway interdiction strategy, their primary area of operations soon centered upon the Cà Mau Peninsula and the Mekong Delta area in the southern tip of Vietnam. Here they patrolled the waterways and performed special operations, including gunfire support, troop insertion and evacuation, and raids into enemy territory.
The Mekong Delta is composed of ten thousand square miles of marshland, swamps and forested areas. The region is interlaced by rivers and canal ways. Controlled by the VC, the interior waterways of the Mekong Delta were used to transport supplies and weapons.
Swift Boats generally operated in teams of three to five. Each boat had an officer in charge, one of whom would also be placed in overall charge of the mission. Their missions included patrolling the waterways, searching water traffic for weapons and munitions, transporting South Vietnamese marine units and inserting Navy SEAL teams.
When the Swift Boats began making forays up the waterways into the interior of the delta, they initially took the carriers by surprise, causing them to drop their materials and run off into the overgrowth. Occasionally a short firefight would break out. As it became clear that control of the waterways was being contested, the Viet Cong developed a number of tactics to challenge the U.S. Navy. They set up ambushes and built obstructions in the canals to create choke points and began to place mines in the waterways.
For the Swifts, coming back down river was always more dangerous than going up river. The passage of a patrol assured their eventual return, providing an opportunity for the VC. Ambushes were typically short lived affairs, set up at a river bend or in a narrow canal that restricted the maneuverability of the boats.Symmes War on the Rivers p. 148 A wide variety of portable weapons were used in attacks, including recoilless rifles, B-40 rockets, .50 caliber machine guns and AK-47s, often fired from behind earthen bunkered positions.Symmes War on the Rivers p. 136 Engagements were brief and violent, with the ambushers often slipping away into the undergrowth when the boats located the source of attack and began to concentrate their return fire. When attacked the boats would accelerate out of the hot zone, turn and then return as a group, firing as many of their guns as they could bring to bear. They would power past the ambush point, turn and return to attack again until the ambushers were either killed or slipped away. Though most cruising and patrolling was done at 8 to 10 knots, the boats could reach a top speed of 32 knots. Thick brush and vegetation in the delta provided excellent cover for the escaping ambushers. Casualties taken among the river crews were high. Casualties suffered among the VC were difficult to assess, as they would take their dead and wounded away from a firefight. Discovering newly dug graveyards was one of the few ways to confirm VC losses.Symmes War on the Rivers p. 173
The first Swift Boat to be lost during the war was PCF-4, which was lost to a mine in 1966. Two boats, PCF-14 and PCF-76, were lost in rough seas at the mouth of the Cua Viet River near the DMZ, and a third, PCF-77, was lost in a rescue effort during a monsoon at the mouth of the Perfume River on the approach to Huế. All three of these boats were lost in 1966. PCF-41 was lost that same year in an ambush when it was hit by fire from a 57 mm recoilless rifle. Its controls destroyed and coxswain killed, it ran aground at speed. When the crew ran out of ammunition it had to be abandoned. It was recovered the next day but was too badly damaged to be repaired, so was salvaged instead.
PCF-43 was lost to a rocket attack in 1969.Symmes War on the Rivers pp. 120–22 Several other Swift Boats had been lost to river mines, but had been salvaged and either repaired or used for spare parts.
When Vietnamization was implemented, several Swift Boats were turned over to the South Vietnamese Navy.
Controversy over loss of PCF-19
On the night of 15/16 June 1968, U.S. Marine Corps aircraft spotters on the ground began reporting unidentified helicopters near the DMZ. The first report stated that four helicopters had been detected and were proceeding toward Tiger Island, just off the North Vietnamese coast at an altitude of . These spotters observed the aircraft visually, using Starlight Scopes and by radar. Over the course of the night, Air Force pilots reported 19 additional helicopter sightings. On this same evening the guided missile heavy cruiser , operating near the DMZ, also began reporting helicopter activity in the vicinity of Bến Hải, Cap Lay and Tiger Island. At 00:10 on the 16th, an unidentified aircraft fired three rockets or missiles at Boston, but none hit the vessel.
At 01:00 on 16 June 1968 in the same area, PCF-19 was struck by two missiles, one struck the cabin just below the pilothouse on the port side, the other hit the engine room. The boat sank in four minutes. Four of its crewmen were killed, and two others badly injured.Steffes, pp. 68–71, official U.S. Navy OinC (Officer In Charge) PCF-12 After Action Report The remaining crew managed to swim free from the sinking craft and cling to a life raft until arrived on scene at 01:30. As soon as the survivors were on board, Point Dume departed the scene to drop them off at the Cua Viet Base for a medevac to Danang. In the meantime, the crew of PCF-12, which had arrived on the scene at 01:50 to continue the search for survivors, noticed illumination rounds being fired that were not their own. Opting to investigate, the officer in charge ordered the boat to speed to the Cua Viet River. When PCF-12 was from the river mouth, crewmembers observed two sets of aircraft lights off the port and starboard beam, about away and above the water. The boat commander immediately got on the radio and requested permission to engage the aircraft. At 02:25, PCF-12 received a single rocket from seaward at a low trajectory. The rocket passed a couple of feet over the main cabin and exploded in the water ten feet from the boat. PCF-12 came about, increased speed and moved away from the kill zone while bringing its .50-caliber guns to bear against an aerial target hovering at with lights blinking. The aircraft decreased altitude and turned off its lights. After a short time, PCF-12 stopped to observe the scene and saw two aircraft appeared off its beams again with lights on. The boat commander contacted the marine observer and inquired about their status. The marines told him that they could not identify the aircraft because they did not have their identification, friend or foe (IFF) transponders turned on. At 02:35, the aircraft near the beach fired 40–50 rounds of .50-caliber tracer fire at the PCF. All rounds landed astern. PCF-12 responded with machine-gun and mortar fire.