The curved-roof trailers are certainly a different approach to streamlining than we see on this side of the Atlantic, where aerodynamic improvers are added to box-shaped vehicles whose roofs remain flat.
The newly ordered units, 60 of them, will be used on secondary runs in cities and towns, Tradeteam said in a statement. Tests show that even in this type of service with a lot of sitting during deliveries and low speeds, a teardrop trailer can save 2% in fuel while covering 50,000 miles per year.
"The new trailers were part of our staged upgrade process," said Gavin Murdoch, managing director at Tradeteam. "We upgrade secondary distribution trailers after around 10 years and wanted to extend the success of our primary distribution teardrops trailers to our secondary distribution network.
"Trailers have a longer lifespan than the tractors we use so it is important to make the right choice and this style is not just eye-catching - it decreases drag and increases efficiency, which is something we are looking to achieve across the board as part of all our operations"
The primary distribution trailers are heavier units used in long-haul operations. Purchased last year after testing in 2010, they save 5% in fuel, the company said.
The curved roof smooths the flow of air over a trailer's top. The trailers are also close-coupled to the tractor to shorten the gap and keep air from getting inside, where it's whipped into drag-inducing turbulence.
Teardrop trailers are showing up around the UK, says the builder, Don-Bur Trailers & Bodies Ltd. It claims they can save 11.3% in fuel, according to fleet tests. Cutting fuel use by 10% reduces carbon dioxide emissions by 8.3 tonnes.
The teardrop shape is an invention of nature, of course. Designers see it also in raindrops, themselves shaped by rushing through the air, and have adapted it to mechanical objects.
In the automotive world, the teardrop goes back to a car designed by a German engineer in 1921 and is now widely used in automobiles like the Toyota Prius, Don-Bur says on its website.
To me the teardrop trailers are reminiscent of the radically streamlined tractor-trailers bought by Labatt's Brewing of Toronto in the 1930s and late '40s. They delivered beer throughout Canada while capturing publicity and attention everywhere they went.
That story and more are told in the upcoming June issue of Heavy Duty Trucking. Watch for it.