Bring on the Quads

Trucking operators could achieve higher operating masses without the paperwork and expense of PBS. A new proposal by the National Transport Commission takes a pragmatic problem solving approach to getting higher productivity trucks on the road.

The announcement suggests operators could increase the payload of certain heavy vehicle combinations by up to 16 per cent on some routes by allowing quad axle groups in place of current triaxles.

“We’re investigating whether quad-axle group vehicles should be able to use higher mass limits without having to go through the performance based standards (PBS) application and approval process,” said Paul Retter, NTC CEO. “This could unlock significant productivity gains for many transport operators by cutting red tape and reducing fuel use.

“Quad-axle group vehicles have the capability to safely carry up to 12 per cent more payload than the current mass limits allow, but are currently restricted to the same limits as tri-axle heavy vehicles under the law, unless they undertake the performance based standards (PBS) application and approval process.”

The NTC’s has proposed an option whereby the road authorities would allow quad axle vehicles to carry increased mass on routes previously assessed as adequate for PBS approved vehicles without having to go through the PBS process.

Under this option, a class 3 notice would be developed to allow vehicles with quad-axle groups (primarily used by B-double and semitrailer combinations) to increase mass by four tonnes at GML to 24 tonnes, and to operate at 27 tonnes under HML, without the current need to obtain approval through PBS scheme.

“The PBS scheme was always intended as a platform where we could test innovative vehicle designs, and this would eventually lead to broader use of these vehicle designs outside the scheme,” said Retter. “After seven years operating safely under the PBS scheme, it is clear we have enough evidence to take these vehicles to the next stage.”

There is also a proposal by the NTC to give concessions to twin steer prime movers allowing an increase in GCM of four tonnes to 46.5 tonnes at GML under the Heavy Vehicle National Law, and to operate with a class 3 notice at 49.5 tonnes under HML.

“For example, currently some shipping containers are double handled once they leave port because twin steer semi-trailers can only carry their full payload capacity in a restricted area, even though these kinds of heavy vehicles are designed to carry this weight safely,” said Retter. “Heavier containers often have to be unloaded and broken down to be transported by multiple vehicles, wasting time and money.”

The NTC said its investigation also explored a change to the mass limits for tri-drive prime movers towing a semi-trailer but found this to be unnecessary, as these vehicles are not widely utilised within the jurisdictions which adopted the Heavy Vehicle National Law.

More detailed explanations can be found at the NTC website, talking about quad axles and twin steers.

Public submissions are open until April 26 and can be made through the NTC website.