Monitor in 1968 | |
Class overview | |
---|---|
Name | Monitor |
Operators | |
General characteristics | |
Type | River monitor |
Displacement | 66 short tons (60 t) |
Length | 60.5 ft (18.4 m) |
Beam | 17.5 ft (5.3 m) |
Draft | 3.3 ft (1.0 m) |
Installed power | 2×225 hp (168 kW) |
Propulsion | two Gray Marine 6-71 diesel engines |
Speed | 8 knots (15 km/h) |
Range | 110 nautical miles (200 km; 130 mi) |
Complement | 11 |
Armament |
|
Armor | XAR-30-type steel and bar armor |
The Monitor was a highly modified version of the LCM-6 developed by the United States Navy for use as a mobile riverine assault boat in the Vietnam War. Another version served as a Command and Control Boat (CCB or Charlie Boat).
The Monitor was similar in many respects to the Armored Troop Carrier (ATC). The Monitor was 60.5 feet (18.4 m) long with a 17.5 feet (5.3 m) beam and a 3.3 ft (1.0 m) draft. Displacing 66 short tons (60 t), it could achieve a top speed of 8 knots (15 km/h; 9.2 mph) knots with its twin Gray Marine 225-hp diesel engines, however armor and weapons reduced the effective speed to 4-7 knots. High-hardness XAR-30-type steel and bar armor provided ballistic protection for the crew from rounds up to .50-caliber in size and offered some protection against high explosive antitank rounds up to 57mm. Below-waterline hull blisters provided added hull protection, minimized draft, and increased stability. [1] : 175
The chief difference between the Monitor and the ATC could be seen in the well deck area. Monitors had a rounded bow as opposed to a drop-down ramp, making them slightly longer than the ATC (60.5 feet vs 56 feet). They also mounted additional weaponry—a 40mm gun turret forward and an 81mm mortar amidships—and carried four additional sailors to help man those weapons and operate the boat. The 81mm mortar was the only indirect-fire weapon fielded by River Flotilla 1 and, with the assistance of an artillery observer, could hit targets up to 4,000 yards (3,700 m) away. [2] [3] Like any mortar, however, this one had a low muzzle velocity, making it ineffective against hardened enemy positions such as bunkers. The Monitor’s main weapon was the 40mm cannon—a very accurate direct-fire weapon that packed a tremendous punch. The 40mm cannon was the only weapon in the Mobile Riverine Force's inventory capable of smashing mud bunkers, but the rounds tended to damage rather than destroy these fortifications, allowing the Vietcong to quickly repair and reuse them for future ambushes. The 40mm guns also had such great range that Monitor crews had to take great care not to hit friendly forces or civilians when employing them. [1] : 177
The Command and Communications Boat (CCB or Charlie Boat) served as flagships for river squadron and river division commanders as well as command posts for Army battalion commanders. They were similar to Monitors except they contained a communications suite amidships rather than an 81mm mortar. The communications suite had five AN/VRC-46, three AN/GRC 106, one AN/PRC-25, and one AN/ARC-27 radios—giving it the ability to communicate with units on land, air and sea. The CCB also featured Raytheon Pathfinder 1900 radar and a Decca navigation installation. [1] : 178
By the end of 1967 each river assault squadron contained 26 ATCs, 16 Assault Support Patrol Boats (ASPBs), five Monitors, two CCBs and one refueller (a modified LCM). [1] : 174
In mid-1967, when the Vietcong constructed bunkers capable of withstanding 40mm rounds, RIVFLOT 1 began exploring the idea of deploying flamethrowers on riverboats as a potential bunker buster. On 4 October, the M132A1, an Army flamethrower vehicle, was shoehorned into an ATC. Commanders hoped the M132A1’s 32-second burst and 150 yards (140 m) range would not only neutralize enemy bunkers but also deter river ambushes. Tests proved satisfactory, but the M132A1, weighing 23,000 pounds (10,000 kg), was too heavy for the Navy’s needs. Instead, lighter M10-8 flamethrowers were installed on six Monitors delivered in May 1968. Nicknamed "Zippo" after the popular cigarette lighter, these Monitors mounted two M10-8 flamethrowers, each with an effective range of 200–300 yards (180–270 m). With 1,350 US gallons (5,100 L; 1,120 imp gal) of napalm fuel, the M10-8 could lay down a sheet of flame for 225 seconds. Sailors would make napalm by mixing a powder consisting of the coprecipitated aluminium salts of naphthenic and palmitic acids with gasoline. Compressed air propelled the napalm through the flamethrower, and a gasoline lighter acted as the trigger. [1] : 178
In order to provide heavier firepower 8 Monitors were produced with an M49 105 mm howitzer mounted in a T172 turret.
The only surviving boat is CCB #C-18 on display at Naval Amphibious Base Coronado, California.
A monitor is a relatively small warship that is neither fast nor strongly armored but carries disproportionately large guns. They were used by some navies from the 1860s, during the First World War and with limited use in the Second World War.
The Vietnam War involved the People's Army of Vietnam (PAVN) or North Vietnamese Army (NVA), National Liberation Front for South Vietnam (NLF) or Viet Cong (VC), and the armed forces of the People's Liberation Army (PLA), Army of the Republic of Vietnam (ARVN), United States Armed Forces, Republic of Korea Armed Forces, Armed Forces of the Philippines, Royal Thai Armed Forces, Australian Defence Force, and New Zealand Defence Force, with a variety of irregular troops.
The LCM-8 is a river boat and mechanized landing craft used by the United States Navy and Army during the Vietnam War and subsequent operations. They are currently used by governments and private organizations throughout the world. The acronym stands for "Landing Craft Mechanized, Mark 8".
Patrol Boat, Riverine, or PBR, is the United States Navy designation for a small rigid-hulled patrol boat used in the Vietnam War from March 1966 until 1975. They were deployed in a force that grew to 250 boats, the most common craft in the River Patrol Force, Task Force 116, and were used to stop 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 weapons shipments. In this role, they frequently became involved in firefights with enemy soldiers on boats and on the shore, were used to insert and extract Navy SEAL teams, and were employed by the United States Army's 458th Transportation Company, known as the 458th Sea Tigers.
In the Vietnam War, the Mobile Riverine Force (MRF) (after May 1967), initially designated Mekong Delta Mobile Afloat Force, and later the Riverines, were a joint US Army and US Navy force that comprised a substantial part of the brown-water navy. It was modeled after lessons learned by the French experience in the First Indochina War of Dinassaut and had the task of both transport (of soldiers and equipment) and combat. The primary land base was at Đồng Tâm Base Camp, with a floating base which operated in the major rivers of the Mekong Delta. Soldiers and sailors went out in river boats from the floating base to assault the Viet Cong. During part of the 1968-69 period, there were two such mobile bases operating in different parts of the Delta, Mobile Riverine Groups Alpha and Bravo. The MRF played a key role in the Tet Offensive.
The Patrol Craft Fast (PCF), also known as Swift Boat, were all-aluminum, 50-foot (15 m) 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.
River monitors are military craft designed to patrol rivers.
The landing craft mechanized (LCM) is a landing craft designed for carrying vehicles. They came to prominence during the Second World War when they were used to land troops or tanks during Allied amphibious assaults.
Armored Troop Carriers (ATC), often called Tangos from the phonetic alphabet for T, were LCM-6 landing craft modified for riverine patrol missions. They were used by the Mobile Riverine Force (MRF) of the United States Army and Navy in the Vietnam War. They were also used by Republic of Vietnam Navy (RVNN) and Khmer National Navy.
The Cambodian Civil War was a military conflict that pitted the guerrilla forces of the Maoist-oriented Communist Party of Kampuchea and the armed and security forces of the Nonaligned Kingdom of Cambodia from 1967 to 1970, then between the joint Monarchist, Maoist and Marxist-Leninist National United Front of Kampuchea alliance and the pro-western Khmer Republic from 1970 to 1975. Main combatants comprised:
USCGC Point Welcome (WPB-82329) was an 82-foot (25 m) Point-class cutter constructed at the Coast Guard Yard at Curtis Bay, Maryland in 1961 for use as a law enforcement and search and rescue patrol boat.
The Mk 18 Mod 0 was a 40x46mm grenade launcher used by the United States Navy during the Vietnam War and also the last known hand crank operated firearm since the Gatling gun. It was replaced by the Mk 19 grenade launcher in service with the United States Armed Forces.
The Dinassaut was a type of riverine military unit employed by the French Navy during the first Indochina War. It's an example of Riverine artillery.
Operation Kentucky was a multi-battalion operation conducted by the United States Marine Corps in the area south of the DMZ in Quảng Trị Province. This was another operation to secure the Con Thien area from the People's Army of Vietnam (PAVN). The operation ran from 1 November 1967 until 28 February 1969.
USCGC Point Caution (WPB-82301) was the first 82-foot (25 m) USCG Point class cutter constructed at the Coast Guard Yard at Curtis Bay, Maryland. She was built and commissioned in 1960 for use as a law enforcement and search and rescue patrol boat. Since the Coast Guard policy in 1960 was not to name cutters under 100 feet (30 m) in length it was designated as WPB-82301 when commissioned and acquired the name Point Caution in January 1964 when the Coast Guard started naming all cutters longer than 65-foot (20 m).
Operation Coronado XI was the eleventh of the Operation Coronado series of riverine military operations conducted by the U.S. Mobile Riverine Force (MRF) and units of the Army of the Republic of Vietnam (ARVN), designed to secure Cần Thơ in the aftermath of the Tet Offensive. It ran from 12 February to 3 March 1968.
Operation Coronado X was the tenth of the Operation Coronado series of riverine military operations conducted by the U.S. Mobile Riverine Force (MRF) and units of the Army of the Republic of Vietnam (ARVN), originally planned as a sweep of western Dinh Tuong Province and eastern Kien Phong Province, however with the outbreak of the Tet Offensive on 31 January 1968 it instead became the MRF reaction to eject Vietcong (VC) forces from Mỹ Tho and Vĩnh Long. It ran from 23 January to 12 February 1968 and resulted in 269 VC killed for the loss of 12 U.S. killed.
The Assault Support Patrol Boat (ASPB) (also known as the Alpha Boat), was a heavily armed and armored riverine patrol boat developed by the United States Navy for use in the Vietnam War from late 1967.
San Diego Marine was a shipbuilding company in San Diego, California. To support the World War 2 demand for ships San Diego Marine built: minesweepers and sub chasers. San Diego Marine was opened in 1915 as San Diego Marine Construction shipyard Captain Oakley J. Hall. The company was sold to Campbell Industries in 1972. It was sold again in 1979 and renamed Southwest Marine. Boatbuilding ended in 1983. Southwest Marine was sold to U.S. Marine Repair in 2003. The named changed to BAE Systems Ship Repair in 2005. The shipyard is located at 2205 East Belt Street, San Diego.