The maximum weight and dimensions of heavy vehicles on European roads are set by common rules. This framework remained fixed for many years; but emission targets and efficiency pressure have brought the rules' update onto the agenda. The change has two main axes: flexibilities granted to aerodynamic equipment, and the opening of the way for longer vehicle combinations.
Room Is Opening Up for Aerodynamic Devices
Under the classic rules, maximum length banned every extra centimetre added to the rear of the trailer, which in practice blocked proven solutions such as boat tails. The updated approach allows folding aerodynamic devices, under certain conditions, not to count towards vehicle length. Similarly, room is being granted for streamlined, extended cab forms; efficiency thus stops conflicting with the legal dimension limit.
Implications for Design
- The rear door and hinge area must be designed together with folding panel mechanisms
- Lighting and marking must remain visible in both the open and closed positions of the device
- Axle loads and manoeuvrability must be reverified for longer combinations
- Country-to-country crossing rules must be factored into the operation plan on international routes
Some member states are already trialling longer vehicle combinations on their own networks; the debate is now moving towards their cross-border use. The message for the trailer manufacturer is clear: those who design modular, aerodynamic platforms adaptable to new length scenarios are preparing for tomorrow's market today.
References
- Van Raemdonck, G. M. R. & Urila, I. (2019). A Study in Options to Improve Aerodynamic Profile of Heavy-Duty Vehicles in Europe. Sustainability, 11(19), 5519. DOI: 10.3390/su11195519