alt Hacker News> They absolutely do design trucks for aerodynamics
I know next to nothing about trucks, and vehicles in general, but something I've noticed, and probably everyone else, is that trucks in the US looks very different from trucks in Europe, it's very easy to identify which one is a US-like truck vs a Europe-like one, because of the shape of the "cab" or whatever that part is called.
So one design has to be clearly better than the alternative, given that aerodynamics works the same all around the world, but still the designs are uniquely... unique.
But why is it like this? If trucks were designed for aerodynamics, shouldn't one of the designs have "won" by now, or are they truly equal in terms of aerodynamics?
Replies
Mostly length regulation, and the prevalence of "sleeper" cabs and other trip length related factors. Economies are a little more self contained and less overland-transcontinental in Europe as well - the amount of freight going Rotterdam to Istanbul is a lot smaller than the amount of freight going LA to Boston, and it's a significantly shorter journey regardless.
Front-engine designs are much easier for a mechanic to work on. Cabovers are much more length-efficient.
If we were overly concerned with aero, you would see multiple unit designs like Turnpike Doubles or triples (or in an extreme, Australian road trains) - https://www.fhwa.dot.gov/policy/otps/truck/wusr/chap02.cfm. For areas where we're too operationally locked in to singles, you would see 60 footer container trailers like they have in a few states in the western US.
You would also, in 2026, hopefully see multi unit designs where the trailers are self-propelled vehicles that can separate and dock automatically at half a mile an hour.
Videos can show the difference visually and note some wider patterns where Euro trucks continued to evolve in other ways -
https://www.youtube.com/watch?v=WpenLsHEHaY
https://www.youtube.com/watch?v=GZRHjhoURz0
https://www.youtube.com/watch?v=LVDIGe0y-to
https://www.youtube.com/watch?v=C0iUiyQOn5E
All trucks have standard shipping container trailers. Europe has strict length limits for the overall cab/trailer that preclude a hood in front of the cab. There is great resistance to changing the law, even though long-nosed trucks are vastly more aerodynamic, because the law provides protection for european truck makers from American competition.
My understanding is that in Europe regulations focused on the length of the whole vehicle, whereas in America the length of the cab and trailer were regulated separately.
Also American truckers do a lot more long-haul work and American roads are noisier, so they prefer being more insulated from the engine.
Did a bit of research: https://news.ycombinator.com/item?id=47121031 - different countries have different legal requirements, despite air being the same everywhere.
This is down to regulations. The total length of the vehicle is capped in Europe so to get more useful cargo space, the cab is shortened to a cab over engine design with a completely flat (short) nose. Making the cab longer or more pointy/aerodynamic cuts from the length available to the trailer. There’s usually more money inside the trailer than in the fuel savings so everyone accepted this solution.
> If trucks were designed for aerodynamics, shouldn't one of the designs have "won" by now,
Because aerodynamics is not the only concern the manufacturers are thinking about.
The difference is in the regulation. The maximum allowed length for a semi-truck is shorter in the EU than in the USA. And since they both want to transport the same length of container the European truck had to be designed shorter.
My dad used to drive concrete delivery trucks in europe. Most were the european arrangement with the cab over the engine, but one of them he drove had the American style long-nose. It was so unusual that they nicknamed the truck after this feature. They called it "csőrike" which is hungarian for "the one with the beak".
He also said it was a lot easier to maintain the long-nosed vehicle. With the european cab-over design you have to first secure everything in the cab and then tip the cab forward to have access to the engine and transmission. While with the long-nosed concrete truck you could just open the hood and get to work.