Twelve pallets of bagged sand on the flat-deck
Tama holds a full Class 3 licence and drives a 2018 rigid flat-deck, GLM 23,000 kg, tare 9,800 kg. The axle ratings are 7,100 kg on the single steer axle and 16,000 kg for the tandem drive group. He picks up 12 pallets of bagged sand at 1,000 kg each, 12,000 kg in total. The forklift driver loads all 12 hard against the headboard, but the deck is only long enough for ten, so the last two are stacked on top of the front two, making a 2.6 m high block. Tama secures the load with two ratchet straps, each rated at 2,500 kg lashing capacity, running straight over the top of the stack. He drives 40 km to site without stopping. At the site gate the weighbridge shows 21,800 kg total, with 8,900 kg on the steer axle.
1. Is the truck within its legal mass limits? Work through the numbers.
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Total mass: tare 9,800 kg plus 12,000 kg of sand = 21,800 kg, which is under the 23,000 kg GLM. The truck is legal on total mass.
The axles tell a different story:
- Steer axle: 8,900 kg against a 7,100 kg rating - 1,800 kg over. That is an axle overload offence even though the total is fine.
- Drive tandem: 21,800 − 8,900 = 12,900 kg against a 16,000 kg group rating - comfortably within.
This is a classic heavy-vehicle problem: legal overall, illegal at the front, because heavy pallets loaded hard against the headboard put mass ahead of the steer axle. The fix is load position, not less load - move the rear pallets back over the tandem, drop the stacked pallets to the deck if the length allows, and reweigh. Persistent steer-axle overloads also chew out steer tyres and shorten the life of steering components, so it is a maintenance problem as much as a compliance one.
2. Is the load restrained to the required standard? Show the arithmetic.
Read the worked answer
No. The standard figures for load restraint are 0.8 g forward, 0.5 g sideways and 0.5 g rearward.
- Forward: 0.8 × 12,000 kg = 9,600 kg of restraint required.
- Sideways: 0.5 × 12,000 kg = 6,000 kg required.
Two straps at 2,500 kg lashing capacity give 5,000 kg in total, and that is the theoretical figure before allowing for the angle of the strap over a 2.6 m high block, which reduces the effective hold. So forward restraint is roughly half of what is needed, and sideways restraint is short as well.
The 2.6 m stack compounds the problem: pallets of bagged product stacked two high can move as a block and topple as a unit. The load needs either substantially more rated straps in a proper pattern, or a rated headboard or barrier plus straps, and the stacked pallets should be re-stacked or banded so they behave as one stable item rather than two loose ones.
3. What should happen before the truck moves, and who carries responsibility for the load?
Read the worked answer
Before it moves: unload or reposition the front pallets rearward, take the stacked pallets down and band each stack, re-secure with enough rated straps to meet 0.8 g forward, reweigh to confirm the steer axle and total are within ratings, and only then depart. If that cannot be done at the pick-up point, the truck does not leave loaded.
Responsibility is shared, and the exam expects you to say so. The driver is responsible for the load he drives and has both the right and the duty to refuse to move an overloaded or inadequately restrained vehicle, even under pressure from a loader or dispatcher. The operator holds the primary duty to ensure loads are positioned, secured and within mass limits, and the loader who placed the pallets is part of the same chain. In practice, a photograph of the secured load before departure and a load sheet recording the weights and strap ratings are cheap protection if something goes wrong later.