WABCO's OptiFlow boat tail

Trailer manufacturers are warning that cab manufacturers could delay the delivery of EU legislation aimed at improving truck and trailer aerodynamics.

The draft legislation, which is out for consultation this month, aims to change current regulations on truck and trailer dimensions to allow for more rounded truck fronts and the addition of aerodynamic devices, such as boat tails, on the back of trailers.

The proposed changes to the regulations could deliver operators fuel savings of up to 10% a year on long distance routes, according to Transport Commissioner Violet Bulc.

If the amendments get the go-ahead truck and trailer manufacturers will be able to begin building these aerodynamically improved cabs and devices as early as 1 September 2020.

The trailer amendment allows aerodynamic devices and equipment up to 500mm in length to be added to trailers, so long as they are not used to increase the cargo area and are retractable or foldable when the vehicle is not in use.

Trailer manufacturers welcomed the consultation this week but raised concerns about the legislation linking trailer aerodynamic devices to cab modifications.

Lionel Curtis, technical director of Cartwright Group, told motortransport.co.uk: “I think this is a great move because the trailer’s improved shape will dramatically reduce drag co-efficient by 5%-6% which could cut operators’ fuel bills by around 3% a year.

“However I am concerned that that the legislation for boat tails could be delayed because it is linked to truck cab modifications. Unlike trailer manufacturers, who are very keen to see this enacted, cab manufacturers will not be interested in introducing these changes on cabs for years because of pressing costs and so their opposition could act as a drag factor on the legislation.”

Richard Owens, Don-Bur group marketing manager, echoed Curtis’s view. He said: “There is a concern in that respect and I think it would be a good thing to separate the two if it means the boat tail legislation can go through the European Parliament more quickly.”