The Military Load Classification (MLC) is a system of standards used by

NATO The North Atlantic Treaty Organization (NATO, ; french: Organisation du traité de l'Atlantique nord, ), also called the North Atlantic Alliance, is an intergovernmental military alliance between 30 member states – 28 European and two No ...

to classify the safe amount of load a surface can withstand. Load-carrying capacity is shown in whole numbers for vehicles, bridges, roads, and routes. Vehicles are classified by weight, type, and effect on routes. Bridges, roads, and routes are classified by physical characteristics, type and flow of traffic, effects of

weather Weather is the state of the atmosphere, describing for example the degree to which it is hot or cold, wet or dry, calm or stormy, clear or cloudy. On Earth, most weather phenomena occur in the lowest layer of the planet's atmosphere, the ...

, and other special conditions.STANAG 2174. Military Routes and Route/Road Networks. 10 August 1978. Latest Amendment, 16 February 1987.

How the system is applied

Usually, the lowest

bridge A bridge is a structure built to span a physical obstacle (such as a body of water, valley, road, or rail) without blocking the way underneath. It is constructed for the purpose of providing passage over the obstacle, which is usually somethi ...

classification number (regardless of vehicle type or conditions of

traffic flow In mathematics and transportation engineering, traffic flow is the study of interactions between travellers (including pedestrians, cyclists, drivers, and their vehicles) and infrastructure (including highways, signage, and traffic control devi ...

) sets the load classification of a route. If no bridge is located on the route, the worst section of road governs the route's classification. Vehicles having higher load classifications than a particular route are sometimes able to use that route if a recon overlay or a special recon shows that a change in

traffic control Traffic management is a key branch within logistics. It concerns the planning control and purchasing of transport services needed to physically move vehicles (for example aircraft, road vehicles, rolling stock and watercraft) and freight. Traffic ...

, such as making a bridge a single-flow crossing, would permit use of the route by heavier traffic. Whenever possible, the basic

military road {{Use dmy dates, date=November 2019 The following is a list of military roads worldwide. Australia * Part of the A8 (Sydney) between Neutral Bay and Mosman * Military Road, part of Route 39, Melbourne * Military Road, off Wanneroo Road just north ...

network is composed of average routes and includes a number of heavy traffic routes and a few very heavy traffic routes. The class of a military road maneuver network is fixed by the minimum route classification of the network. Individual routes are grouped and identified in broad categories. The MLC scale is defined in terms of a set of 16 hypothetical standard wheeled vehicles and a set of 16 hypothetical tracked vehicles. Originally, these hypothetical vehicles were typical of actual

military vehicle A military vehicle is any vehicle for land-based military transport and activity, including combat vehicles; both specifically designed for, or significantly used by military and armed forces. Most military vehicles require off-road capabiliti ...

s used in NATO countries. Standard tracked vehicles are designated by MLC numbers ranging from 4 to 150, which correspond to the gross vehicle weight in

short ton The short ton (symbol tn) is a measurement unit equal to . It is commonly used in the United States, where it is known simply as a ton, although the term is ambiguous, the single word being variously used for short, long, and metric ton. The vari ...

s. Each standard tracked vehicle is also defined in terms of track width, length, and spacing. Standard wheeled vehicles are designated by the same MLC numbers (4 through 150), which correspond to about 85% of the gross weight in short tons. Each standard wheeled vehicle is defined in terms of gross weight, number of

axle An axle or axletree is a central shaft for a rotating wheel or gear. On wheeled vehicles, the axle may be fixed to the wheels, rotating with them, or fixed to the vehicle, with the wheels rotating around the axle. In the former case, bearing ...

s, axle spacing, and axle load.

Maximum single-axle load

In addition to the standard hypothetical wheeled vehicles, a maximum single-axle load is specified for each MLC. This is used to represent the loading on very short spans, when only one axle is on the span at a time.

References

{{reflist NATO Standardization Agreements Military vehicles Roads Standards of the United States