Scourge of the Brown Water Navy

The remains of a B-40 rocket propelled grenade (RPG) round that struck Lieutenant Ron Wolin's river patrol boat (PBR) during the Tet Offensive in January 1968, one of the artifacts featured in the Brown Water section of the Hampton Roads Naval Museum's new exhibit, The Ten Thousand-Day War at Sea, The U.S. Navy in Vietnam, 1950-1975. (M.C. Farrington/ Courtesy of Ron Wolin)

Although most of what Lt. Wolin wrote has since faded from the stabilizing fin of the B-40, the date is still legible (M.C. Farrington/ Courtesy of Ron Wolin)

By A.J. Orlikoff
Hampton Roads Naval Museum Educator

At about 0600 on January 30, 1968, Lieutenant Ron Wolin was shaving when he was alerted of increased enemy activity on the Ham Luong River.  Reports continued to filter in of enemy attacks. This was the beginning stage of what would be known as the Tet Offensive: a massive nationwide assault by the North Vietnamese Army (NVA) and Viet Cong (VC) on Army of the Republic of Vietnam (ARVN) and American forces. 

Lt Ron Wolin with a captured Viet Cong flag aboard his PBR in South Vietnam.  Note the uniform shirt at left with his River Section 534 unit patch, which Wolin designed. (Courtesy of Ron Wolin)

The commanding officer of River Section 534, Wolin ordered his available river patrol boats (PBRs) to deploy and relieve an assault on the U.S. Military Assistance Command, Vietnam (MACV) Compound in Ben Tre.  Upon approach to the compound, Wolin noticed enemy forces crossing a bridge across a large canal and ordered his forces to attack. The PBRs of River Section 534 made several attack runs in the canal, strafing the VC forces on the bridge and on the banks with relentless fire, disrupting the enemy assault on the MACV compound.

on March 26, 1968, a strike force of river patrol boats (PBRs) head down the Bassac River to assault the Viet Cong stronghold on Tan Dihn Island. PBRs adapted their tactics to minimize the threat of enemy rockets, favoring fast moving assaults while utilizing their superior firepower to strafe enemy positions. While casualties were unavoidable given their lack of armor, the adaptability of Navy riverine forces undoubtedly saved lives and helped break the back of Viet Cong forces during the Tet Offensive. (U.S. Navy photo/ National Archives and Records Administration)

On one of their passes, a B-40 rocket slammed into Wolin’s PBR. Wolin recalled “First thing I knew I’m looking up on my back and I didn’t realize for a few seconds what had happened. I was thrown into the armor plate.…I remember looking down at my leg and realizing my pants had been blown open. I thought, ‘Gee, that’s strange.’” The rocket hit had wounded every man on board and completely knocked out their controls. Drifting towards a bank in the canal, only the timely intervention of another PBR saved Wolin and his men from capture. Wolin refused to be taken to a hospital, for he knew that this would mean losing command of River Section 534. As a result of his leadership, bravery, and valor, Wolin was awarded the Silver Star for his actions in blunting the VC assault on the Ben Tre MACV Compound.

Shattered fiberglass and fractured aluminum at the stern of a river patrol boat (PBR) caused by an enemy B-40 rocket is shown in this photo from October 1969. The B-40 rocket was regarded as the scourge of American riverine forces due to its light weight, ease of manufacture, and strong explosive force.  PBR hulls were originally designed for civilian pleasure craft but were adapted into fast shallow water draft vessels capable of engaging the enemy in the vast waterways of the Mekong Delta and the other rivers of South Vietnam. As a result, PBRs had no armor and were vulnerable to B-40 attacks. (U.S. Navy Photo)

Wolin had survived an attack from B-40 rocket, the scourge of the U.S. Navy’s riverine forces. NVA and VC forces used a variety of rocket launchers to counter American riverine forces operating in South Vietnam and the B-40 was by far the most feared of them. Though often inaccurate, the B-40 was an extremely cost effective means to engage superior American naval forces in the Mekong Delta.

An unfired, demilitarized B-40 rocket-propelled grenade is shown next to the remains of the B-40 that hit Lt. Ron Wolin's PBR during the Tet Offensive. An additional section (not shown) made of wax-coated cardboard and containing propellant would have extended behind the tail boom fins. (M.C. Farrington/ Courtesy of Ron Wolin)

Closeup of the markings on the warhead of Ron Wolin's B-40. The warhead diameter was 80 millimeters. (M.C. Farrington/ Courtesy of Ron Wolin)

The most effective recoilless weapon used by the Viet Cong was the B-40 rocket launcher. A North Vietnamese copy of the Soviet Manufactured RPG-2 (the less famous predecessor of the ubiquitous RPG-7), the B-40 packed a powerful punch. The B-40 was capable of launching a high explosive fin stabilized 80 mm PG-2 high-explosive anti-tank (HEAT) round at ranges of up to 150 meters away.

This Viet Cong propaganda film frame grab shows the B-40 in launching configuration after the grenade assembly has been inserted into the launcher from the front.  The launcher was a 40mm-wide steel tube equipped with a trigger mechanism and simple sight and was sheathed in wood to protect the grenadier from the intense but brief but intense heat generated at launching. (BBC) 

A close cousin, the B-50, was also used by Viet Cong forces, instead firing the Chinese Type 50 HEAT round. Originally designed by the Soviet Union to penetrate up to 7 inches of tank armor, the B-40 easily penetrate the unarmored fiberglass hulls of PBRs and was even capable of damaging the armored vessels of the Mobile Riverine Force. A single direct hit from a B-40 was enough to completely disable a PBR, as was the case with Wolin’s. The B-40 remained a primary threat to American riverine forces throughout the Vietnam War.

On January 30, 1968, the Viet Cong and NVA launched a massive country wide offensive across South Vietnam. Designed to coincide with the lunar holiday ceasefire, the Tet Offensive surprised American and ARVN forces, with the Viet Cong even directly attacking the US Embassy in Saigon. While Tet was ultimately a crushing defeat for the Viet Cong, the surprise, intensity, and ferocity of the attack stunned the American public and further soured public opinion on America involvement. As illustrated in the above photo, Viet Cong fighters often used the rivers of the Mekong Delta for transportation and it was up to the riverine forces of Task Force 116 and 117 to stymie the Tet Offensive along the rivers of the Mekong Delta. (U.S. Army Photo)

The threat of B-40 attacks forced PBR crews to adapt to an incredibly challenging combat environment. Not only did PBR crews have to patrol the rivers of the Mekong Delta, interdict enemy supply boats, and engage hostiles, they had to so with the threat of a single rocket hit incapacitating the entire boat. This type of vulnerability, unprecedented in U.S. naval history, caused Navy riverine forces to utilize the PBR's advantages of speed, firepower, and communication to counter the threat of recoilless rocket attacks.

This November 1967 photo taken from the cockpit of a Navy Seawolf gunship, captures a low altitude rocket attack on a Viet Cong position along the shore of the Ham Luong River. Established on April 1, 1967, the HAL-3 (Helicopter Attack Squadron 3) “Seawolves” were formed to provide mobile and fast fire support to any beleaguered friendly units in the Mekong Delta. (U.S. Navy Photo  XFV-2053-B-11-67)

While recoilless weapons were relatively accurate against a stationary target, a PBR speeding at 25-30 knots was much harder target to hit, especially when the enemy fighter was under fire from one of the boat’s numerous weapons. PBR crews also used teamwork, communicating with other PBRS and naval assets like HAL-3, “The Seawolves” to counter potential threats with overwhelming force. Recoilless rifles were a potent threat to American riverine sailors yet they never hindered the effectiveness and lethality of American riverine forces in the Mekong Delta. American riverine forces met the challenge of Viet Cong head on and accomplished their missions with bravery and honor.

A shirt that was worn by Lt. Ron Wolin while he was commanding officer of River Section 534, River Patrol Force (Task Force 116) in South Vietnam, currently on display in the riverine section of the Hampton Roads Naval Museum's new exhibit, The Ten Thousand-Day War at Sea, The U.S. Navy in Vietnam, 1950-1975. (M.C. Farrington/ Courtesy of Ron Wolin)

Lt. Ron Wolin's uniform shirt along with the B-40 and B-40 fragment currently on display in the Riverine section of the Hampton Roads Naval Museum's new exhibit, The Ten Thousand-Day War at Sea, The U.S. Navy in Vietnam, 1950-1975. (M.C. Farrington)