Riverine artillery

Riverine artillery refers to artillery employment on a river, generally on floating barges. Transport of field artillery is difficult through the moist ground and riparian forest adjacent to low-gradient rivers. Traditional naval artillery is mounted on deep-draft vessels unsuited for operations in shallow rivers.

France developed the Dinassaut (assault river division) concept early in their effort to fight communist guerrillas in French Indochina. The value of artillery was demonstrated by French ships when coastal Mon Cay became the only French garrison along the Chinese border to survive a 1950 Viet Minh offensive.

During the Vietnam War, the United States employed riverine artillery due to the difficulty of transporting and emplacing artillery pieces in marshy areas. The formation of a riverine task force (composed of 2d Brigade of the 9th Infantry Division and the U.S. Navy River Assault Flotilla 1) increased the importance of artillery support in riverine areas, and fixed locations near river areas proved unsatisfactory. In December 1966, 1st Battalion, 7th Artillery positioned M101A1 105mm howitzers aboard LCM-6 landing craft, with the intent that the craft be towed to a supported area and moored to a riverbank.

Later, it was established that the LCM-6 was too small to serve effectively, and howitzers were positioned on Navy AMMI pontoon barges. When these proved to difficult to move and to have too deep of a draft, barges formed of Navy P-1 pontoons were the workable solution. M101A1, and later M102 howitzers were mounted onto a baseplate welded to the barge deck, allowing the howitzer to be traversed 360 degrees.

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