Glossary of Technical Terms*

Like most industries, transportation employs technical terms which are not familiar to the lay reader. Certain Army terms also are not understood outside military circles. The following brief nontechnical definitions will save the reader the inconvenience of seeking explanations elsewhere.

A-frame	Device used as a field expedient in beach operations when cranes were not available in sufficient quantity. Usually attached to an amphibian truck or other vehicle, it could lift approximately 4,000 pounds.
Amphibian vehicle	Vehicle capable of operating on both land and water.
Balanced cargo	A mixture of heavy and light cargo, which approximately fills the cargo space and weighs the ship down to its maximum draft.
Balanced stocks	An accumulation of supplies of all classes in quantities necessary to meet requirements for a fixed period.
Balloon cargo	Items, such as assembled trucks, which occupy an exceptionally large amount of space in relation to their weight.
Bareboat charter	A form under which the charterer hires the vessel only and provides the crew, supplies, fuel, and other operating requisites.
Berth	Place where a ship lies at pier, quay, or wharf.
Block loading	System, used extensively in the Pacific from late 1943 for resupply of invasion troops, involving the loading of vessels with carefully organized blocks of supplies such as troops were likely to require soon after landing.
Block system (rail)	System, often used in single-track operation, whereby only one train can operate over a particular section or block at a time. In order to move a train from one station to another, the operator must clear the intervening section with the operator at the end of the block.
Block system (trucking)	A form of relay operation whereby trucks operate continuously from origin to destination and back with changes in drivers at intermediate stations, which are usually located one day’s travel time apart.
Bunkerage	Fueling or coaling of ships.
Cannibalize	The use of equipment or parts from damaged materiel to maintain other materiel.
Combat loader	A vessel especially equipped for combat loading. The Navy provided two types—APA (transport, attack), and AKA (cargo ship, attack).
Combat loading	Loading a ship with equipment and supplies required by assault forces, and stowing the various items in such a manner as to make possible their rapid unloading in the order needed.
Combat zone	Forward area of a theater of operations, where combat troops are actively engaged.
Commodity loading	The loading of vessels with a specific type of cargo such as rations, vehicles, or ammunition, to fill an immediate on-the-spot requirement.
Communications zone	The part of a theater of operations behind the combat zone, where supply, transportation, and other facilities are located and services performed.
Deadline	Remove from action, as for repairs.
Dead-weight tonnage	Actual carrying capacity of a vessel, including stores, fuel, water, and cargo.
Double heading	The use of two locomotives to pull a train, usually over rugged hill or mountain country.
Dry cargo ship	Any ship, except a tank ship carrying liquids in bulk. As used in World War II the term applied to passenger ships as well as freighters.
Dumb barges	Nonpropelled barges.
Echelon maintenance	System of maintenance and repair of materiel and equipment in which jobs are allocated to organizations in accordance with the availability of personnel, tools, supplies, and time within the organizations. Categories range from first echelon, which included simplest forms of upkeep to the fifth, which included heavier types of repairs.
Filler cargo	Packaged and bagged supplies which can be stowed in small and irregularly shaped spaces in the hold of a ship.
Flatting	Bottom stowing and flooring off of cargo in a vessel in order to provide ballast or an emergency reserve.
Full and down	Term indicating that a vessel has all cargo space filled and that the cargo is sufficiently heavy to take the ship down to the legal maximum draft.
General cargo	Broadly used, the term includes all except bulk cargoes, but in Army usage it may include explosives.
Graving dock	Dry dock used for ship repair or construction.
Interior clearance	The movement of tonnage from the port area to the interior.
Landing craft	Any vessel used to carry men, equipment, and supplies ashore.
Lighter	Boat or flat-bottomed barge used for loading or unloading ships.
Line of communications (LOC) hauling	The transporting of bulk supplies of personnel over theater main supply roads in accordance with priorities and commitments of the theater or a comparable command. This hauling was usually intersectional in scope, in contrast with local or base hauling.
Long ton	Weight ton of 2,240 pounds.
Measurement ton	40 cubic feet; sometimes called ship ton, since it was used chiefly in connection with ocean transportation.
Metric ton	Weight ton of 2,204.6 pounds.
Packaged gasoline	Gasoline in cans or drums.
Palletized or skid- loaded cargo	Cargo fastened to a small wooden platform, often equipped with bridle and runners for towing along the ground. Facility in moving pallets on beaches made up for some loss in shipping space.
Passing track or siding	A track adjacent to and parallel to the main track with a switch at both ends connecting it with the main track. Used in single-track operation, the passing track was used to permit trains traveling in opposite directions to pass.
Pier	Structure that projects into water where vessels berth for loading or unloading cargo, usually constructed at right angles to the shore line.
Port capacity	The tonnage that can be discharged daily from ships, based only on evaluation of the physical facilities of the port.
Port or beach clearance	The tonnage that may be transported inland daily from a beach or port by available means of inland communication, including highways, railroads, and inland waterways.
Prestowing	A system similar to block loading, used in connection with the invasion of Normandy.
Quay	Wharf parallel with basin or harbor, with water on one side.
Rail wagon	Railway car.
Reefer box	Refrigerated box, used on board ship or brought ashore.
Reefer vessel	Refrigerated vessel.
Semitrailer	Wheeled vehicle without motive power, intended primarily for the transportation of cargo or equipment designed to be towed and attached to a truck-tractor by means of a fifth-wheel device, a portion of its weight being carried by the truck-tractor. It is equipped with retractable gear to support the front end when detached.
Short ton	Weight ton of 2,000 pounds.
Spotting	Placing railway car on a track for loading or unloading.
Tanker	Tank ship for transporting petroleum products and other liquids in bulk.
Theater of operations	Army command including the area of actual fighting (combat zone) and the adjacent area utilized for supporting administrative and supply activities (communications zone).
Topping off	Top stowing of cargo to complete the loading of a ship.
Trailer	Vehicle designed to be towed, provided with a drawbar or tongue for attachment to a coupling mounted on the towing vehicle.
Train-order system	A method of train operation used generally in conjunction with a timetable, showing where scheduled trains will meet.
Truck-tractor	Wheeled vehicle propelled by a self-contained power unit, designed primarily as a truck chassis, but provided with a fifth wheel for attachment to and for towing semitrailers.
‘Tween decks	Space between the main deck and the hold.
War flats	Flatcars of 56-ton capacity manufactured for the War Department.
Weight ton (British)	2,240 pounds.
Weight ton (U.S.)	2,000 pounds.
Wharf	Structure where vessels berth for loading or unloading cargo, usually constructed parallel to the shore line.
Zone of interior	The area which furnishes manpower and materiel to the forces in theaters of operation. During World War II, the zone of interior consisted of the United States.