Army Watercraft

The Army has about 300 watercraft of various classes in its fleet. The US Army Tank-automotive and Armaments Command -- TACOM -- manages the Army's watercraft program as part as its mission to provide and sustain mobility. Watercraft fall into two categories, lighterage and floating utility. These two categories are defined according to the mission they perform.

• Lighterage are craft used to transport equipment, cargo and personnel between ships, from ship-to-shore or for intratheater transport. Lighterage are further classified into conventional displacement (landing craft), amphibious (wheeled), or modular causeway systems (powered ferry).
• Floating Utility craft perform operations incidental to water terminal operations, except lighterage service. Watercraft in this category are harbor and ocean going tugs, pusher tugs, floating cranes, barges, floating machine shops, floating causeway and Roll-On/Roll-Off (RO/RO) discharge facilities (RRDF).

Each vessel in the Army's marine fleet bears an individual serial number, preceded by an applicable prefix.

Watercraft are used in four principal roles.

Port and Harbor Support. The most common support craft are tug boats. Modernizing the Army watercraft fleet will result in two sizes of tugs in the inventory. Large tugs are used to dock and undock large ocean ships and to position other non-self-propelled craft in and around the harbor complex. Small tugs assist in docking operations and maneuver barges in shallow or constricted waters where large tugs cannot operate. Additional equipment such as floating cranes unload heavy lifts when shoreside support is not available.

Inland Waterway (IWW). IWW operations are generally characterized by the use of tugs and barges to extend the theater transportation system from deep-draft ports to inland discharge points. Using host nation assets must be strongly considered since those craft are designed for use in their specific countries' waterway system. Landing craft and LSVs can supplement standard tug and barge operations.

LOTS Support. Landing craft and amphibians are the principal craft that transfer cargo from anchored ships to shoreside unloading points. Adverse underwater gradients or offshore obstacles, such as reefs or sandbars, preclude efficient use of landing craft. In these circumstances, using amphibians is more advantageous. Landing craft, on the other hand, are generally more durable; have a greater capability for accommodating heavy, outsize cargo; and are more economical to operate. Floatable causeway components provide interfaces at shipside, particularly in conjunction with the discharge of RO/RO vessels, and also span from the shore outward to landing craft that otherwise would be grounded. These systems complement each other. The planner must develop a LOTS support package that blends the advantages of the different equipment into an efficient force mix package.

Intratheater Support. Intratheater support takes the nature of a transshipping concept that applies to contingency operations in underdeveloped countries. The few available major ports must be efficiently used in conjunction with other ports or limited capacity sites not served by military sealift command operations. Vessels that best support this type of use are craft with relatively shallow draft that can transport a variety of cargoes and whose sustainability permits extended operation. The LSV has been specially acquired for this use. The 2000 class landing craft, utility (LCU), although of far less capacity than the LSV, can augment intratheater support when not required in its primary LOTS role.