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Maintenance and repair of Army watercraft pose problems somewhat different from those for other types of Army equipment. Support maintenance facilities for watercraft must be located at or near the water's edge. Rather than being echeloned along the forward axis of a theater as in other systems, these facilities are generally spread laterally along the theater's rear boundary. Except for some inland waterway systems, their orientation is toward the rear.

The Army watercraft maintenance system supports a variety of watercraft that can be classified in two broad categories: lighterage and coastal harbor and inland waterway vessels.

The lighterage fleet consists of amphibians and landing craft, which deliver cargo between ship and shore. Amphibians are small craft that can operate on land and water. They include both wheeled and air-cushion vehicles. Landing craft are shallow-draft vessels designed for beaching, unloading cargo through a bow ramp, and retracting from the beach under their own power.

The Army watercraft fleet consists of small harbor and larger, long-range coastal vessels. Harbor craft consist of small tugs, command control and security boats (picketboats), floating cranes, and barges that generally operate in or around harbors and on inland waterways. Coastal vessels include large tugs and cargo ships that can operate over long distances along coastlines and on inland waterways. These vessels provide volume line-haul intratheater redistribution of cargo.


The US Army four-level maintenance system gives maintenance support to Army watercraft. The four-level maintenance concept for watercraft provides maximum self-sufficiency, supportability, and maintainability with a minimum use of personnel, parts, materiel, and equipment.

The objectives of Army watercraft maintenance are--

  • Early detection and correction of faults that affect safety afloat.

  • Sustaining an operational readiness posture by doing maintenance where it can be most effectively and economically performed.

To achieve these objectives, the four-level watercraft maintenance system provides a flexible, system-oriented supply support structure tailored to the unique character and low density of the single-user Army watercraft fleet.

The principle of performing maintenance at the lowest possible level consistent with the personnel, skills, tools, repair parts, and time available also applies to watercraft. When operational conditions require, watercraft units may be authorized to perform higher level maintenance tasks than those normally authorized at unit level. Some watercraft units have a direct support (DS) maintenance section in the TOE specifically for these requirements.

The maintenance system must remain flexible enough to prevent a backlog of non-mission-capable watercraft and to provide procedures and facilities to absorb increased maintenance requirements during periods of intense operational requirements. Early detection of potential problems during preventive maintenance checks and services will alleviate many situations that cause long maintenance downtime.

A responsive maintenance system is maintained through close liaison between operating units and their designated maintenance support unit. To provide a firm basis for support planning and to ensure sufficient watercraft availability, maintenance unit commanders must be informed of all actual and anticipated operational changes. There must be a constant exchange of capability information between the support maintenance units and the watercraft units they support.

Supported units may request technical assistance at any time, but it should be provided on a regular basis. This ensures more effective and efficient user maintenance, reduces demands on the supporting unit, and increases the unit's mission efficiency. AR 700-4 gives detailed guidance on maintenance technical assistance. Technical assistance consists of--

  • Furnishing instruction and technical guidance to supported units.

  • Providing information on new maintenance and supply techniques, procedures, and publications.

  • Providing guidance to implement maintenance directives and orders.

The strength of a boat unit is measured by the number of craft that are fully mission capable not by the number of landing craft assigned to it. Watercraft are always critical items of equipment. Deadlining (for other than scheduled maintenance) results in a loss of tonnage, a heavy drain on the available stock of repair parts, and a rapid decline in unit efficiency.

Supervision of preventive maintenance is a major command responsibility. It requires careful planning, periodic technical inspections, and a systematic unit preventive maintenance program. The commander should immediately instruct all officers and NCOs upon their arrival in the unit of the importance of a strict preventive maintenance program.

Commanders must not tolerate haphazard servicing and operation. Time must be reserved from operations for unit preventive maintenance which the officers and the NCOs of the watercraft units must supervise. During operations, preventive maintenance is performed at every opportunity.

Jury-rig equipment for steering and ramp operation is placed aboard vessels for emergency use. If this equipment must be used, parts must be requisitioned and replaced on the original equipment as soon as possible. The supply system must establish demand data and preserve jury-rig materials aboard the boat for future use.

Normally, depending on the type unit, 25 to 33 percent of the watercraft in a unit are programmed for unit or higher level maintenance. Accordingly, plans should be based on a 67 to 75 percent assigned craft availability for sustained operations. When craft are transported on cargo vessels or in landing ships, dock (LSDs), minor repair and maintenance may be performed en route. However, maintenance during movement must not substitute for the time reserved for maintenance before embarkation. Maintenance before embarkation ensures that the maximum number of craft will be ready at the start of the operation. The following conditions may greatly reduce the number of craft available for employment during an operation:

  • Operation in heavy surf or in waters studded with reefs or full of debris.

  • Long delays on a shallow beach.

  • Storms.

  • Lack of opportunities for preventive maintenance.

  • Other abnormal conditions.


Maintenance allocation charts are the primary means to identify the appropriate maintenance level to perform required maintenance. Charts are developed on a craft-by-craft basis. Authorized crew functions depend on the operating range of the vessel, crew size, and space available for storing tools, test equipment, and repair parts. Based on this criteria, Army watercraft can be divided into three maintenance groupings:

  • Amphibians, small landing craft, and picket-boats (small crews, short operating range, and limited space).

  • Small tugs, large landing craft, and floating cranes (larger crews and greater storage space).

  • Large tugs and other coastal vessels (large crews, greater storage space, and long operating range under open ocean conditions).

The four categories of watercraft maintenance are unit, direct support (DS), general support (GS), and depot maintenance.

The crew or the crew and a shore-based unit maintenance section normally perform all marine unit maintenance. For landing trail and amphibians, separate TOE sections provide backup shore-based unit maintenance and direct support maintenance. Watercraft maintenance other than unit level can be provided by a watercraft maintenance team (detachment) or a watercraft maintenance company. When watercraft are grouped (task organized) into company-sized, mission-structure elements, teams can augment unit level maintenance. A quick turn-around of end items by replacement and minor repair characterizes watercraft unit maintenance. Unit maintenance includes preventive maintenance checks and services, inspection, cleaning, adjusting, lubricating, tightening, and other tasks authorized by the applicable maintenance allocation chart. Unit level maintenance operations provide for mandatory parts list stockage in the form of a prescribed load list (PLL).

With the exception of those craft that have engine room personnel assigned as part of the crew, operator maintenance of watercraft is largely limited to proper operation and before-, during-, and after-operation checks to detect initial defects. Therefore, the bulk of the unit maintenance work load falls to the unit maintenance section. Depending on the type unit and if they are authorized to perform DS level repairs, this section performs all the unit and/or DS maintenance functions indicated in the maintenance allocation chart. Some units have DS maintenance sections in their TOE.

Watercraft unit capabilities are based on an average availability of 67 to 75 percent of the assigned craft, depending on the type unit. A constantly supervised operator and unit maintenance effort is required to sustain this rate. When maintenance at this level is neglected, the nonoperational rate may become so high that the unit mission cannot be accomplished.

A system of daily and scheduled preventive maintenance inspections and services will be established and performed according to applicable technical manuals. When the manuals are not available or have not been published TB 55-1900-202-12/1 provides the minimum preventive maintenance guidance. If scheduled maintenance is performed regularly and properly, the percentage of craft down due to equipment or mechanical failure should seldom exceed the 25 percent rate. When the deadline rate exceeds 25 percent, the commander should ensure that proper watercraft operation and maintenance services are being performed.

The appropriate TMs list repair parts and special tools for each craft. These manuals list allowances of repair parts the unit may maintain. The levels prescribed cannot be exceeded unless properly authorized. If the company commander determines that certain components suffer a higher mortality rate than the stock level will support, the higher command level is informed so they can authorize remedial action. Remember that excess repair parts contribute appreciably to the weight of the unit and creates storage and accountability problems. More importantly, the parts removed from supply channels are denied to units immediately needing them.

Marine intermediate maintenance units are allocated functions on a return-to-user basis according to the basic Army four-level concept. These functions vary for each craft as a consequence of the crew and unit functions (authorized by range, crew, or space criteria). Watercraft support maintenance units provide backup supply and maintenance support and perform those functions too time-consuming or operationally burdensome for the operating unit. The support maintenance unit provides one-stop support from its base location and forward on-site service via floating maintenance teams. Its maintenance operations are aboard a floating machine shop. It is located in a harbor or port facility where there is a high density of watercraft. Marine intermediate maintenance units are assigned to either a terminal group or a terminal battalion.

Contract personnel normally perform marine depot maintenance. The depot maintenance activity is responsible for drydocking and associated repairs particularly for larger craft, unless haul-out facilities are available at the unit level.


The operating unit is responsible for recovery of disabled watercraft. It is normally accomplished by sister vessels. The support maintenance unit is responsible for recovery requirements beyond the operating unit's capability. Disabled watercraft are normally evacuated to the nearest repair facility. When this is not feasible, watercraft are moved to the nearest haven for protection during repair or until further recovery or evacuation is completed. Within the immediate area of operations, the terminal battalion is responsible for recovery and evacuation. Outside the immediate operational area, the in-theater controlling authority provides recovery and evacuation assistance.

The operating unit classifies disabled watercraft and coordinates their evacuation to a support maintenance or other facility. The marine intermediate maintenance unit also functions as a maintenance collection point. Permanently disabled watercraft will be cannibalized as much as possible before final disposition.


The transportation company (watercraft maintenance) (GS) provides direct and general maintenance support for US Army watercraft and their organic navigational equipment. The unit also receives, stores, and issues watercraft-peculiar repair parts and items.

The transportation company (watercraft maintenance) (GS) is normally assigned to a transportation command (TOE 55-601L) or a transportation terminal group (TOE 55-822L). However it may be attached to a transportation terminal battalion (TOE 55-816), or it may operate independently under an appropriate commander's supervision.

At Levels 1, 2, and 3, the unit can provide the approximate man-hours of production maintenance shown in Table 9-1. The unit receives, stores, and issues about 9,000 line items of watercraft-peculiar repair parts and other items. This unit also performs watercraft and marine salvage operations.

The TOE authorizes 207 personnel and about 533,600 pounds (67,000 cubic feet) of equipment requiring transportation. Non-TOE equipment and supplies make up about 71,400 pounds (2,000 cubic feet). In one lift using organic assets, the unit can move about 230 personnel and 1,692,000 pounds (136,000 cubic feet) of equipment and supplies. All equipment is transportable by air, except--

  • Barge, deck cargo.

  • Crane, wheeled, 20-ton.

  • Chamber, recompression, 100 pounds per square inch (psi).

  • Landing craft, mechanized, 69 feet.

  • Landing craft, utility, 115 feet.

  • Repair shop, floating marine equipment, nonpropelled.

NOTE: This unit has a requirement for approximately 63,000 annual productive manhours of diving support which is provided by an engineer dive detachment (TOE 0550 LA00). The detachment provides area support on a required basis and can tailor the support package with a number of different types of engineer dive teams.

Although shore-based repair facilities may be established if required, the bulk of the unit's work is done aboard the floating repair shop. This shop contains all the facilities necessary to support the company mission. Three repair sections, a supply platoon, and a repair control section normally function aboard the floating repair shop.

Because the floating repair shop requires a protected berth, the company normally operates in an established port terminal that is centrally located to other terminals.

The transportation company (watercraft maintenance) (GS) requests its repair parts directly from the theater materiel management center, which directs the field depot that stocks the requested items to ship them. Items this company repairs are either returned to the using unit, to supply stocks within the company, or to the appropriate field theater supply activity that stocks marine and/or watercraft items.


The transportation floating craft maintenance detachment (TOE 55550AL00), performs DS/GS maintenance on Army floating craft and marine equipment.

The detachment is normally assigned to a headquarters and headquarters company, transportation terminal group, TOE 55822L or to a headquarters and headquarters company, transportation terminal battalion, TOE 55816L. It can augment a transportation company floating craft maintenance (GS), TOE 55613L000 or may operate independently for a limited time where needed.

This detachment performs all types of maintenance on floating craft, including hull and engine repair. It can provide the personnel, skills, and equipment to perform the following annual manhours of productive maintenance:

    Hull Repair and/or Inspection 3,100
    Hydraulic Repair 3,100
    Machining 6,200
    Marine Engine Repair 27,900
    Metal Work 18,600
    Plumber/Pipefitter 3,100
    Radio/Radar Repair 3,100
    Refrigeration/Air Conditioning/ Heating 3,100
    Carpentry/Masonry 3,100

NOTE: This detachment requires about 6,200 annual productive manhours of diving support for underwater reconnaissance missions, welding, cutting, salvage, hull repair, and structural inspection and/or repair. An engineer dive detachment (TOE 05530LA00) provides it on an area support basis. The support can be tailored with a combination of different types of dive teams.

This unit receives, stores, and issues approximately 2,000 line items for watercraft and marine related repair and/or replacement parts and performs minor marine salvage operations in geographically limited conflicts.

This unit depends on the unit to which it is attached for food service support and on other appropriate elements of the theater for health, religious, legal, finance, and personnel and administrative services.


A maintenance warrant officer on the terminal battalion staff provides staff supervision of unit and direct support levels of maintenance for watercraft and marine equipment. He conducts periodic inspections, prepares reports of inspections, disseminates technical information, and provides technical guidance and maintenance assistance when required.

A maintenance officer on the terminal group staff provides staff supervision over maintenance functions for the command. The commanders of the attached maintenance units act as special advisors on floating craft maintenance to the watercraft and/or marine maintenance officer and to the terminal group commander.


Maintenance management requires the combined efforts of all operating and maintenance personnel to ensure an effective and efficient program.

The terminal group and battalion commanders to which the unit's operating craft are attached are responsible for watercraft maintenance management. Watercraft maintenance management
includes --

  • Establishing the requirements and procedures that allow adequate time to perform operator preventative maintenance checks and services and to train personnel to recognize conditions that, if not corrected in a timely manner, will lead to serious maintenance problems and excessive downtime for watercraft and marine equipment.

  • Providing tools, test equipment, facilities, funds, and repair parts and other maintenance supplies that are essential to the maintenance mission.

  • Planning, programming, and budgeting for proper use of maintenance resources.

  • Providing technical supervision and management control over maintenance programs and activities.

  • Reviewing accomplishments relative to effective and economical uses of maintenance resources.

  • Evaluating maintenance concepts, policies, doctrine, plans, and procedures to ensure that they help to accomplish the overall military mission.

  • Recommending new maintenance concepts, policies, doctrine, plans, and procedures for the Army maintenance system.

  • Coordinating with the maintenance element of the appropriate materiel management center and providing it with information on maintenance programs, status, requirements, and performance.


The maintenance management update contains DA Pamphlet 738-750 which establishes equipment record keeping procedures and describes in detail the use of forms and equipment records for watercraft and marine equipment maintenance. The forms are used to record the operation, maintenance, and historical data to manage the Army watercraft fleet.

Within the unit itself, the records are a maintenance management tool for the commander. This information permits the commander to properly evaluate--

  • Equipment operations.

  • Modification work orders (MWOs) required and applied.

  • Equipment availability.

  • Frequency of equipment failure.

  • Repair parts requirements.

  • Unit materiel readiness.

  • Equipment shortcomings and deficiencies.

  • Support requirements.

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