The
Brown Water Navy in by Robert H. Stoner, GMCM (SW)(Ret)
The
naval war in At
the same time, the United States Navy found itself embroiled in a war that was
fought at first, off the coastal waters of South Vietnam, and then in the river
deltas, smaller waterways and canals of the country. To combat North Vietnamese infiltration of
men and supplies by sea, three Task Forces were formed: TF-115 called Operation
MARKET TIME; TF-116 called Operation GAME WARDEN; and TF-117 called the MOBILE
RIVERINE FORCE (a joint amphibious Army-Navy riverine operation). MOBILE RIVERINE FORCEIn March 1966 a joint committee of
Army and Navy personnel drew up tentative plans for the establishment of a
Mekong Delta Mobile Afloat Force (MDMAF). On 1 September 1966, the first
administrative unit of the new MDMAF was commissioned at The purpose of the MRF was to support
an infantry brigade and an artillery battalion using modified landing craft,
support ships, and specially designed assault boats. The strike unit would be a self-contained
amphibious assault force with all support elements except aircraft [added
later]. Because the Marines were heavily
engaged in I Corps, a brigade from the Army’s 9th Infantry Division
was chosen as the infantry component of the MRF. The Navy’s component of TF-117 was a
wide variety of ships and boats. The first unit, River Assault Flotilla One
(RivFlotONE) was composed of River Assault Squadron 9 ( In 1967, Task Group 117.3 was
composed of USS BENEWAH (APB-35), USS COLLETON (APB-36), Above: The
headquarters for the MOBILE RIVERINE FORCE was the joint Army-Navy base located
at Dong Tam, just up river from the city of My Tho on the way to Vinh
Long. Below: A detail
map of the Dong Tam base. The boat
turning basin is the square-shaped blue area just off the large canal that
joins the My Tho River. The city of Above: The Dong
Tam base. The Navy side is in the
foreground with the boat turning basin.
The Army side is in the background.
[Photo: Jerry Laviviere] The MRF continued to grow to full
strength during 1968 with the addition of two more River Assault Squadrons ( Boats of the MRF The main craft of the All the riverine boat conversions
were well protected with both conventional and “stand-off” armor. This
“stand-off” or bar armor was a series of 1-inch concrete reinforcing steel rods
set about 12 to 18 inches from the boat’s hull and superstructure. The bar armor was designed to detonate an RPG
(rocket propelled grenade) or recoilless rifle rounds before they hit the armor
plate. “Stand-off armor” proved to be very effective against both hand held and
crew served weapons used by the VC, and significantly reduced casualties and
damage when an riverine craft was hit by enemy fire. Some ATCs were modified with a
helicopter flight deck counted over the troop wells (called Program 5). This
was done initially to provide a platform for helicopters to land on for
delivery of supplies and transfer of personnel. Almost immediately, helicopters
were pressed into service for casualty evacuation since they were often the
only place for a helicopter to land during operations in the Delta. Some of the
ATCs with helicopter pads were designated ATC(H)s. The ATC(H) was fitted as battalion aid
station and carried a doctor and either Army medics or Navy corpsmen. One ATC(H) also carried refrigerated whole
blood and there was always a fully equipped operating table ready to perform
emergency surgery. Each river squadron had an ATC
fitted-out as a refueler. The refueler ATC carried bladders of combat gasoline
(mogas) or aviation fuel (avgas) under the flight deck to refuel the squadron’s
boats, assault craft, and sometimes helicopters. The refuelers proved
indispensable during prolonged operations and pumped huge quantities of fuel to
keep the riverine forces on station. The fire support vessel of the MRF
was the Monitor. These had the same superstructure as the ATC, but were
completely different forward. The
monitor had an open well deck, forward of the superstructure, that contained a
Mk 2 Mod 0 Navy 81 mm mortar and two 7.62mm machine guns. A rounded bow replaced the bow ramp of the
ATC. The redesigned bow mounted a 40mm cannon (with a co-axial 50 caliber
machine gun) enclosed in a turret. The 40mm was the main gun of the riverine
forces and it provided a high volume of fire during landing operations. In
addition, at least two Mark 18 grenade launchers were carried along with the
individual weapons of the crewmen. Later, Program 5 Monitors replaced the 40mm
turret with the 105mm turret of the Marine Corps LVT(H)-6 amphibious tractor
(Amtrac). Initially, an ATC was used to test an
Army M132A1 flamethrower armored personnel carrier ( Two Monitors in each squadron were
also fitted out as Command Control Boats (CCBs). The only major difference
between a regular Monitor and a CCB Monitor was the removal of the mortar pit
aft of the 40mm turret. In its place a command and control shelter was fitted
to serve as the command post for the battalion and task group commanders during
an operation. The CCB Monitor was almost identical to a regular monitor and
carried out much the same function. The Assault Support Patrol Boat
(ASPB) was specially constructed for use by the riverine forces. It was also
designed to serve as a minesweeper and was fitted with a mine countermeasure
chain drag. Lighter and faster than the Monitor, the ASPB was not as heavily
armed or armored. It carried a single 20mm cannon and twin .50 caliber machine
guns or 20mm cannon in two turrets, one in the bow, and one atop the
superstructure. The 81mm mortar was mounted in the stern and a combination of
7.62mm machine guns or Mark 18 grenade launchers were also carried in place of
the mortar. The ASPB had a unique underwater exhaust system that made it the
quietest of the riverine boats. The ASPB was employed for ambushes,
patrols, special operations, reconnaissance, and escort missions. Later in the
war, pairs of single .50 caliber machine guns replaced the 7.62mm machine guns
on the stern while the forward gun turret received eight 3.5-inch rocket
launchers (Mk 47) mounted on their sides. Linked to the machine guns the rocket
launchers could be targeted by elevating or depressing the machine guns and
traversing the turret. Ships of the MRF The MOBILE RIVERINE FORCE had a
number of support ships and craft. The self-propelled barracks ships (APBs)
were purpose-built on LST-542 class hulls to berth a battalion of troops. Built in World War 2, they were modified for
use in However, since these barracks ships
could not handle all the men of the infantry battalions, and artillery
batteries, another non-self propelled barracks ship ( To service and repair the various
riverine boats and landing craft a repair ship was assigned to the support
section of the task force. The job fell to the The last major support vessels of
Task Force 117 were 1156-Class LSTs assigned to the flotilla from the 7th
Fleet. These provided additional storage space that was unavailable on the
APBs. The LSTs housed supplemental
supplies of ammunition, weapons, spare parts, and rations for the riverine
forces during prolonged operations. The LSTs were equipped with a flight deck
and carried the brigade’s helicopter detachment of four helicopters and one
company of infantry. The LSTs also supported a River Assault Division. The final components of the MRF were the
artillery and helicopter barges developed by the Army. The Army quickly discovered that the soggy
terrain of the Mekong Delta was not suited to either artillery or
helicopters. An Army artillery officer
had a fire support barge fabricated from sections of two Ammi pontoons that
enabled a pair of 105 mm howitzers to fire while anchored next to the
shoreline. These barges could also be beached if the tide went out. Helicopters faced a similar problem because
there were few areas for them to land. The ATC(H) provided a partial
solution. A helicopter barge was
developed using sections of Ammi pontoons.
Each of these helicopter barges could accommodated three UH-1
helicopters and was equipped with a refueling system that carried 1,500 gallons
of JP-4 aviation fuel. Army LCM-8
landing craft were used to move the artillery and helicopter barges about and
to supply the barges with fuel and ammunition. The MRF did not lack for
artillery or helicopter support. Ships of the MRF: APBs (4), USS
BENEWAH (APB-35) - class Self-Propelled Barracks Ship Above: The 328-foot USS BENEWAH ( Below: BT2 John Hardy stands next to his .50 machine gun on USS BENEWAH in 1968. The arch-shaped tubes are limit stops for the machine gun. Personal radios were common entertainment aboard ship. [Photo: John Hardy] Below: USS BENEWAH shown with her brood of riverine craft nested alongside the Ammi pontoons tied to her starboard side. [Photo: John Hardy]
Below: USS NUECES ( Below: The Above: KALISPELL (YTB-784) closest to camera, USS WINNEMUCCA
(YTB-785) inboard of YTB-784, and a Light Salvage Lift Craft (YLCC-1) of Harbor
Clearance Unit Below: YRBM-17 (left) and Above: A composite photo of USS ASKARI ( Above: The LST
– Landing Ship Tank, LST-542 class, LST-1156 class The
ships that brought the supplies to the various ships of the MRF and acted as
floating supply, fuel, and ammunition storage were the LSTs. The MRF always had at least one LST-1156
class (and sometimes two) assigned to it from Amphibious Ready Group
BRAVO. The LST-1156 class ships were
improvements over the LST-542 class World War 2 designs. These later LSTs came into service towards
the end of the Korean War and shortly thereafter. They were quite different in appearance from
their World War 2 cousins. Below: USS KEMPER COUNTY (LST-854) off Vung Tau in 1967. Most of the WW2 LSTs carried a crane on the
top deck to assist with off-loading of supplies or lifting large, heavy objects
aboard ship. Like all LSTs, Above: USS WINDHAM COUNTY (LST-1170) off the coast of AKL
– Attack Cargo Light, Camano-class Above: Two of the hardest working ships of the MRF were the
USS BRULE (AKL-28), shown here, and the USS MARK (AKL-12). Both were small Camano-class light freighters
built for the ASPB
– Assault Support Patrol Boat The
ASPB was designed for operations in Above: A drawing of a typical ASPB as it appeared in 1967. The Mk 48 Mod 2 turret on the bow carried two .50 machine guns, the Mk 48 Mod 0 turret aft of the coxswain’s station carried either a Mk 16 Mod 4 20mm gun and a Mk 21 Mod 0 7.62mm machine gun or a Mk 19 Mod 0 40mm grenade launcher. [Drawing: Windjammer Arts] Below: A nest of Vietnamese ASPBs alongside YRBM-20 about 1970. These boats are showing signs of a lot of hard use. Note the muddy water. [Photo: Kent Hawley] Above: In late 1969 many ASPBs were fitted with eight (4x2) 3.5-inch rocket launchers Mk 47. This boat has the Mk 48 Mod 2 turret with the twin .50 machine guns. Rockets were either HEAT (high-explosive, anti-tank) or WP (white phosphorus). [Photo: Tom Lefavour] Below: The Mk 48 Mod 2 turret with Mk 47 3.5-inch rocket launch tubes. The Gunner’s Mate holding a 3.5-inch rocket is explaining the new modifications to the boat crew. The “lumps” on the back of the rocket launch tubes are the contactor latch groups. Each one holds a rocket in the tube and provides a firing contact for the rocket motor. [Photo: Tom Lefavour] Below: A Mk 48 Mod 0 turret on the bow of an ASPB
mounts a 20mm Mk 16 gun and a 7.62mm Mk 21 machine gun. [Photo: Mike Gregory] Above: The MSR (Minesweeper, River) was a conversion of the standard ASPB. These were used as a command and control boat for the MSD (Minesweeping Drone). The MSD was a 23-foot remote-controlled minesweeping boat powered by a 327 Chevrolet gasoline engine. The MSR differed from the standard ASPB by the addition of specialist minesweeping gear and electronics. Also the upper 20mm turret was replaced by two 7.62mm machine guns. Mine Division 113 of Mine Squadron 11 used the MSR boats. This boat is MSR-7. [Photo: Jack T. Walker] Below: Three MSDs of Mine Division 113. The MSD was designed to sweep different types
of river mines and not put a crew at risk.
It was designed to be run remotely from a control boat and was
considered expendable. The MSD was also
capable of manual operation. [Photo: Tom
Lefavour] Above: MSDs of Mine Division 113 operating in manual mode with crews. Keeping the main waterways swept of mines was hot, dirty, tiring, tedious and punctuated with moments of sheer terror. [Photo: Tom Lefavour] Below: The MSD used a 327 Chevy engine and MerCruiser
stern drive. The circular tube is a
propeller guard. The hull of the MSD was
non-magnetic. [Photo: Tom Lefavour] ATC – Armored Troop CarrierThe
ATC was a modified LCM-6 landing craft.
It was 56 feet long by 14 feet wide and was powered by two diesel
engines driving twin propellers. All
versions carried a chain minesweeping dragline for cutting cables of
command-detonated mines in canals. The
ATC had an armored superstructure that had gun tubs for .50 machine guns, 20mm
cannon, or 40mm automatic grenade launchers.
Early ATCs [Program 4] were called “rag tops” due to the fabric cover
over the well deck of the boat. Later
boats replaced the soft top with a hard top [Program 5] capable of landing a
UH-1 helicopter. Called the ATC(H) for
helicopter, some of these boats were pressed into service as a battalion aid
station with doctors and medics to take care of wounded sailors and soldiers. Each
squadron had a refueling boat using an ATC boat. Instead of troops, the well deck of the boat
carried pumps and rubber fuel bladders with diesel fuel for boats or JP-4 for
helicopters. During long operations,
these boats would help keep the boats of the squadron running and the
helicopters flying. Early
on, two ATCs were modified to field flamethrowers. The flamethrowers would burn away the dense
foliage along the riverbanks to reveal enemy bunkers. The Zippo was hated and feared by the
VC. The simplest conversion was the
removal of the soft top on the ATC (T-91-8 and T-112-5) and an M132A1 Another
ATC conversion was the “Douche Boat” that was armed with two high-pressure
water cannons. The water cannons were
used to wash away enemy bunkers and fortifications along the riverbanks. The boat had an auxiliary diesel engine
mounted in the well deck that drove the high-pressure water pump that fed the
two water cannons. A water induction
tube was located on the left side of the boat with a pivoting pickup strainer
head for river water. Above: Below: “Irma La Douche” was a “rag top” ATC with two water cannons. The tall, curving pipes just in back of the soft top are the water cannons. [Photo: Ray F. Longaker, Jr.] Above: A test run of the converted Douche Boat. The water inductor pipe is down (left corner
of stern) and its right water cannon at full pressure. In this photo, the soft top has been removed
from above the well deck. The water
pressure from the cannon is actually causing the boat to list to port. [Photo: Mike Harris] Below: A model of the Douche Boat shows the location of the third engine and water pump for the water cannons. The inductor and its pipe are shown running along the top, portside of the hull. The brown boxes behind the bar armor are C-ration cases. [Model: Ray F. Longaker, Jr.]
Above: Tango T-91-8 is shown with an M132A1 flame Below: A close-up of the M132A1 “flame track” Below: Another Tango boat, T-111-7, was converted to mount two M10-8 flame guns on top of a modified bow. The fuel bladder for the liquid napalm and compressed air tanks were put under armor in the well deck. This is the ATC conversion to a Zippo boat after its turnover to the Vietnamese. The bar armor has been extended around the bow to protect the flame guns, the two are shown on the raised platform on the bow. The deckhouse behind the flame guns is for the boat crew. [Photo: Tom Lefavour] Above: Another Zippo was a conversion of a Below: A nest of ATC(H) boats. The Program 5 boats were assigned to Above: An ATC(H) of Below: A Program 5 ATC(H), Tango-152-1 of Below: Another landing platform for helicopters was the helicopter barges of the Army’s 9th Division. These were made from two Ammi pontoons. Here is one of the division’s OH-23 Raven helicopters on one of those improvised landing platforms. The barges were towed by Army LCM-8 landing craft. [Photo: Larry Webb] Above: Brigadier General William B. Fulton, 2nd Brigade, 9th Infantry Division, confers with one of his officers. The starboard bow of the helicopter barge pusher LCM-8 is shown in the foreground with its bow ramp down. The converted Ammi pontoon helicopter barges could land three helicopters and could provide 1,500 gallons of JP-4 to refuel them during action. [Photo: Larry Webb] Below: Sometimes the helicopters couldn’t set down on the barges and pilots had to improvise. Here a UH-1D medical evacuation helicopter (“Dustoff”) hovers above an Army LCM-8 pusher boat to pickup wounded troops. [Photo: Lee Wahler] Monitors, CCBs, and Zippo Boats The first Monitors and Command and
Control Boats (CCB) were very similar in construction. The main recognition point was the 81mm
mortar pit aft of the 40mm turret on the Monitor and a radio communications
shelter in place of the mortar pit on the CCB.
Initially, two of these Program 4 Monitors were converted by replacing
the mortar pit with two M10-8 flame guns to become Zippo boats. Later, Program 5 Monitors were converted to
Zippo boats by replacing the forward gun turret with two M10-8 flame guns. As originally built, the Program 4
Monitors of Above: Monitor M-92-1 in 1968 showing the lines of the first Program 4 Monitor boats. The tube sticking up to the left of the standing sailor is the 81mm mortar. A 7.62mm machine gun is under the gun cover to the rear of the mortar. [Photo: Ron McAbee] Below: CCB C-91-1 in this 1967 photo shows the similarity to the Monitor. The CCB had multiple radio antennas around the communications shelter that replaced the mortar pit on the Monitor. CCB C-91-1 was a Program 4 boat and the first command and control boat delivered to the newly formed MRF. Note the armored doors of both the turret and communications shelter are opened due to the oppressive heat and humidity. [Photo: Dan Dodd] Above: The first of the Program 4 boats of the MRF were Monitor M-91-1 (left) and CCB C-91-1 (right). This side-by-side shot shows both similarities and differences between the two kinds of craft. [Photo: Doug Lindsey] Below: The Program 4 Monitor M-92-2 became a Zippo with the addition of two M10-8 flame guns behind the 40mm turret. This series of photos shows the Zippo conversion clearing the shoreline growth to expose bunkers. [Photos: Don Blankenship]
Above: Below:
Above: The aft Mk 48 Mod 0 turret on a Program 5 Monitor was surrounded by bar armor. In the left photo, the crew has installed sandbags between the bar armor and armor plate to increase the armor protection. The improvised sandbag armor was not particularly effective. The right photo shows the business end of the 20mm Mk 16 gun and the co-axial 7.62mm machine gun. As seen in the photos, some gunners took the cone-shaped flash hider off their guns (left), while others kept it on (right). [Photos: Steve Lovey (L), Dave Hazelett (R)] Below: A good close-up bow shot of Monitor 2 at SEA FLOAT in early 1970. Note the protective bar armor around the 105mm turret and the twin .50 machine guns mounted on top. This was an uncommon field modification but very wise considering operational area. [Photo: Bill Patterson] Above: A still closer look at the 105mm turret and
twin .50 machine guns of Monitor 2. This
boat was turned over to the Vietnamese in November 1970. [Photo: Bill
Patterson] Below: The Program 5 Monitor and Zippo boats were very
similar. Here are two sitting
side-by-side for comparison with the Zippo on the left (flame guns covered) and
the Monitor on the right. Above: A close-up photo of Zippo Z-132-1 showing both M10-8 flame guns. The flame tube is on the right and the co-axial 7.62mm machine gun is on the left of the flame tube [as seen from the front]. The Zippo could carry over 1,100 gallons of napalm. [Photo: Dewey Pollack] R3 Back to Part 2 End of Part 3 Continue to Part 4 |