Road Trains – the mammoth haulers of goods

Road trains unitrans africa

Road Trains – the mammoth haulers of goods

Road trains or land trains, also known as Long Combination Vehicles (LCVs), are most suitable for countries with large expanses of remote land, in continents like Australia, the US, Canada, Africa (including Malawi, Zambia, Tanzania, Mozambique, Namibia and Madagascar) and some parts of Europe. Products ranging from livestock, grains, fuel, salt and ore to construction materials are suitable for bulk handling and haulage. Road trains are becoming a more common feature in the Southern African mining landscape for the efficient transport of both raw and treated minerals over distances between five and 100km.

Types of Road Train Combinations

Road trains vary in configuration, depending not only on the requirements of the job, but also on the regulations of the country. The basic configuration is a lead truck or conventional tractor unit, called the prime mover, which has one or more trailers attached. Trailers can be fitted with steering axles, allowing the rear axle on each trailer to pivot slightly while turning – this prevents rubbing the edges of the tyres due to the heavy loads placed on them. Road trains (especially in Australia) can be up to 53.5 metres long, which is about 10 car lengths. The combinations described below have different names in countries around the world.


This is a prime mover truck towing a normal lead trailer with a coupling or hitch at the rear. Attaching an additional standard trailer is easily done using a fifth wheel dolly, which is connected to the hitch.

A B double combination
Figure 1: A-Double (source:


A B-double combination consists of a prime mover towing a specialised trailer that has a fifth-wheel mounted on the rear towing another semi-trailer, resulting in two articulation points. In South Africa this is called an interlink.

B Double trailer
Figure 2: B-Double (source:


This is the same as a B-double, but with an additional lead trailer behind the prime mover. Most states in Australia allow these double road trains on public roads under the PBS regulations.

triple road train
Figure 3: B-Triple (source:


An A-Triple or triple road train is similar to the A-double, but with a third dolly and semi-trailer attached. Combinations also exist where B-trailers are hitched to A-Trailers to form AB doubles or AB triples. These extra-long trailers are restricted to large stretched of remote roads due to their poor turning circles. However their large payloads make them a popular choice for mines.

A Triple
Figure 4: A-Triple (Source: wikipedia)

Benefits of Road Trains

  • Greater payloads (current operational payloads of up to 200 tons per road train)
  • Reduction in fleet requirement
  • Decrease in environmental impact with decreased emissions
  • Decrease in rate per ton
  • Increased safety standards

Abnormal length vehicles and performance-based standards (PBS)

High transportation and fuel expenses make up the major portion of logistics costs in South Africa. Industry stakeholders are constantly looking for an alternative solution within the regulatory framework governing heavy vehicles transporting fuel. They are using a performance-based standard to look at regulating heavy vehicles with an increased payload, while still achieving stringent safety standards

If PBS vehicles can be used optimally, the potential savings could exceed tens of billions of Rands each year in fuel savings, reduced damage to roads, as well a reduced number of heavy vehicle accidents.

Current road regulations define a ‘prescriptive box’ that vehicles must fit into (height, width, length). By contrast, PBS aims to design the vehicle to perform at certain levels. Truck and trailers have to pass a set of 16 performance tests, which comprise a combination of low and high-speed manoeuvres, such as emergency lane changes, turning circles, acceleration and braking.

PBS regulations are split into four levels, each having slightly different performance requirements and subsequent route restrictions:

Level 1

Vehicles are allowed to travel on all routes.

Level 2 and above

Requires a detailed route analysis and vehicles are restricted to only drive on those designated routes.

Levels 3 and 4

Vehicles are typically only used on private or very remote roads such as in mines or on large agricultural estates.

As of 2020, PBS vehicles are still part of the Smart Truck Pilot Project and are thus required by law to be part of the RTMS (Road Transport Management System).

Unitrans Africa is a leader in the fuel transportation industry in Africa with a strong footprint in countries like Namibia, Botswana, and Mozambique.  PBS forms part of Unitrans Africa’s overall SHEQ (Safety, Health, Environment and Quality) and Performance strategies. The company is ISO-certified, complying with all the relevant safety, quality, health and environmental standards and is additionally registered on the RTMS.

Customers can be assured that Unitrans Africa strives to save on costs wherever possible and keeps the environment safe by using the PBS system in fuel transport operations.

Unitrans Africa offers land train services for agricultural produce and road train haulage for the mining industry. Find out more about their values of innovation, honesty, excellence, unity, safety and constancy, as well as their ability to provide comprehensive contributions to bulk transportation by contacting them via email.

1 a trailer having wheels at the back but supported at the front by a towing vehicle.