From the commencement of the Viet Nam war the tactical and economic standing of the South’s extensive inland waterways dictated that the U.S. Navy should lead the allied forces during the conflict. 

Intertwined with approximately 3,000 nautical miles of rivers, canals, and streams, the lush Mekong Delta region located south of Saigon had the largest segment of the South Vietnam population and so it constituted the country’s “rice bowl” that produced the majority of the country’s crop of rice.

 

Northward along the coast to the DMZ large rivers stretched inland past vital population centers such as the old imperial capital of Hue that originally rose to prominence as the capital of the Nguyễn lords, a feudal dynasty that dominated much of southern Vietnam from the 17th to the 19th century. Since the country’s road and rail systems were rudimentary it was the waterways that permitted ready access to the region’s most significant resources.  So, whoever could control the rivers and canals acquired the tactical advantage to control the heart of South Vietnam.

 

 Therefore, USN leaders were resolute to have allied forces seize control of the waterways and so they established a plan to initiate the River Patrol Force and designated it Task Force 116 on 18 December 1965 to meet their objective. When the operation took effect the Navy divided Task Force 116 into two separate task groups and assigned them to specific regions within the Delta with Task Group 116.1, a force of 80 PBRs,  assigned to patrol the heart of the Mekong Delta and operate out of river’s edge bases in My Tho, Vinh Long, Can Tho, Sa Dec, and Long Xuyen. And, the second division, Task Group 116.2, which was roughly half the size designated to protect the Rung Sat Special Zone using base areas in Nha Be and Cat Lo. 

 

Consequently, in March 1966 the Navy commenced procurement of river patrol boats (PBRs) built in the United States and then trained their crews at the USN Coronado and Mare Island, California training center, and then deployed the units to Southeast Asia to begin Operation “Game Warden.” The River Patrol Force was also designated River Patrol Squadron 5 for administrative and supply purposes and by August 1968 the force consisted of five river divisions with each commanding two 10-boat squadrons that operated from combat bases along the key rivers, or from Navy ships stationed in the rivers that served as floating base facilities for each PBR section and a helicopter detachment.

 

Operation Game Warden was a joint operation of the United States and South Vietnamese navies in order to deny Viet Cong access to resources in the Mekong Delta. Game Warden and its counterpart Operation Market Time are considered to be two of the most successful U.S. Naval actions during the Vietnam War.

Patrol Boat River or PBR, is the United States Navy designation the small rigid-hulled patrol boats employed during the Vietnam War from March 1966 until the end of 1971. They were deployed in a force that grew to 250 boats and were used to intercept and search river traffic in areas such as the Mekong Delta, the Rung Sat Special Zone, the Saigon River and in I Corps in the area assigned to Task Force Clearwater in an attempt to disrupt enemy weapons shipments. In that role they frequently engaged in firefights with enemy soldiers on boats and on the shoreline, were used to insert and recover Navy SEAL teams, and were employed by the United States Army’s 458th Transportation Company, known as the 458th Seatigers, the  and only Army Unit to employ the Navy River Patrol Boat in Vietnam.

 

The  Rung Sat Special Zone was the name designated during the Vietnam War by the South Vietnam Government and American forces to a large area of the Sác Forest in Viet Nam which is today known as the Cần Giờ Mangrove Forest and was also known as the “Forest of Assassins”.

 

The I Corps Tactical Zone was a corps of the Army of the Republic of Vietnam (ARVN) was one of four corps that made up the ARVN. The area encompassed the northernmost region of South Vietnam, bordering North Vietnam. And, it included five provinces: Quảng Trị Province, (Khe Sanh, Đông Hà, Quảng Trị City), Thừa Thiên-Huế Province, (Phu Bai, Huế City), Quảng Nam Province, (Đà Nẵng, Hội An), Quảng Tín Province, (Tam Kỳ, Chu Lai) and Quảng Ngãi Province, (Quảng Ngãi). The region included the DMZ area where 3rd Marine Division intelligence estimated the combat strength of NVA and VC forces in January 1968 was 40,943 troops. 

 

The PBR proved a versatile watercraft having a fiberglass hull and propelled by a water jet drive that enabled it to operate in shallow and weed-choked rivers. It had a draft of just two feet of water when fully loaded, and the drives could be rotated in order to reverse the boat’s direction, turn the boat within its own length radius, and it come to a stop from full speed in the distance of just a few boat lengths.

The PBR was manufactured in two versions with the first having a 31-foot length and 10 foot, 7-inch beam. And the second, the Mark II version, at 32 feet long with a one foot wider beam and that had enhanced drives to reduce engine fouling, along with aluminum corrosion resistant gunwales.

 

The PBR was typically manned by a four-man crew consisting of a First-Class Petty Officer serving as the boat captain, a gunner’s mate, an engineman, and a seaman. Additionally, each crewman was cross-trained to be able to function in each other’s job in the event one became incapacitated or otherwise unable to carry out his duties. Customarily, PBRs operated in pairs under the command of a one patrol officer stationed on one of the two boats.

 

PBRs were powered by twin 180 Detroit Diesel 6V53N engines linked to Jacuzzi Brothers pump-jet drives that propelled them to top speeds of 28.5 knots, approx. 33 mph.  Their typical armament configuration included twin M2HB .50 caliber machine guns situated forward in a rotating shielded tub, a single rear M60, one or two 7.62 mm light machine guns mounted on the port and starboard sides, and a Mk 19 grenade launcher. Additionally, their small arms complement included M16 rifles, shotguns, .45 ACP handguns, and hand grenades. And, some were equipped with a “piggyback” arrangement of a .50 cal. machine gun on top of an 81mm mortar; while others had a bow-mounted Mk16 Mod 4 Colt 20 mm automatic cannon. 

 

However, what the boats benefited in heavy firepower they lacked in armor or shielding, and although the .50 cal. machine guns had some ceramic armor shielding and the Coxswain’s flat had some quarter inch thick steel armor plating, the boats were designed to depend on rapid acceleration, 

In addition to the PBRs the Navy employed Patrol Craft Fast (PCF) In Viet Nam, also so-called  Swift Boats that were all-aluminum, 50-foot long, shallow-draft vessels that  initially  were deployed to patrol the coastal areas and later worked in the interior waterways as part of the brown-water navy to prohibit Vietcong movement of arms and munitions, transport Vietnamese forces and to insert SEAL teams for counterinsurgency (COIN) operations during the Vietnam War.

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PBRs were retired from active duty by the U.S. Navy immediately following the Vietnam War during the early 1970s. However, they continued operating with the U.S. Naval Reserve units up until 1995 at Mare Island, California prior to the base’s closure due to Defense Base Closure and Realignment Commission (BRAC) action that year. During the Vietnam War, Mare Island was home to the U.S. Navy’s Repair Facilities, Mothballing Operations, Submarine Operations, and Riverine Training Operations for both Swift Boats and PBRs.

 

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