Select Logistics & Transport has taken another step forward in high-productivity freight with the development of a brand-new PBS approved A-double drop deck skel configuration, purpose-built for the carriage of ISO tank containers.
The design and approval process behind this unit highlights what can be achieved when fleet operators, trailer builders, PBS certifiers and assessors collaborate early.
BTT Engineering was engaged by Select Logistics & Transport in early 2025 to review potential High Productivity Freight Vehicle (HPFV) combination types that would best suit a specialised task: transporting ISO tank containers from Longford, Victoria through to Port Augusta, South Australia.
The route demanded a solution that could deliver genuine payload efficiency while remaining safe, stable, and compatible with the infrastructure and access framework along the corridor.
From the outset, BTT focused on finding the most appropriate PBS combination for both the freight task and access environment. After assessing route constraints, payload requirements, axle groupings, and operational practicality, BTT identified the PBS Level 3A 85.5-tonne General Freight Reference Vehicle 4 as the best fit.
This reference vehicle offered the ideal balance of productivity and performance for the Longford to Port Augusta task. In addition, the project required further In-Principle access permits to enable a total operating mass of approximately 84 tonnes, ensuring Select Logistics could meet payload targets without compromising compliance.
Key to the success of the project was ensuring the trailer design precisely matched the intended PBS reference vehicle.
BTT worked closely with the trailer manufacturer Vawdrey and the assessor through the full development cycle, including configuration selection, dimensioning, axle spacing, swept path and performance alignment.
The drop deck skel arrangement was refined to maintain the required design envelope while also achieving the payload management heights necessary for safe and efficient movement of ISO tanks. This included careful attention to deck height, container support points, and overall combination geometry to ensure stability and compatibility with loading facilities.
The outcome is a modern, heavy-duty A-double skel combination ready to deliver real-world efficiency gains for Select Logistics.
The core benefit of this PBS unit is its ability to transport two ISO containers in a single movement, maximising freight efficiency on long interstate legs.
For Select Logistics, this means fewer trips, improved asset utilisation, and a meaningful reduction in cost per tonne moved. Importantly, the combination also supports shorter shuttle movements between manufacturing sites and key Melbourne depots, giving the fleet flexibility across both linehaul and metropolitan tasks.
PBS approvals are fundamentally about achieving higher productivity without sacrificing safety. This project demonstrates that with the right engineering approach, operators can unlock substantial benefits while meeting rigorous performance standards for low-speed manoeuvrability, high-speed tracking, static rollover threshold, and braking performance. The Select Logistics A-double is a strong example of PBS doing what it is designed to do: enabling smarter combinations tailored to a specific freight challenge and route.
With the unit now completed and ready for service, Select Logistics is positioned to expand its ISO tank task capability and support customers with safer, more efficient freight outcomes.
For more information, visit bttengineering.com.au.