> would increase fuel economy by 15-25%
Makes you wonder if/why truck companies don't have aerodynamics experts on their payroll.
Makes you wonder if/why truck companies don't have aerodynamics experts on their payroll.
The reality is just that with the drive cycles and costs and tradeoffs of implementing all this it's not worth it to go this far.
Second, this sort of "round the whole thing" approach has mostly been replaced with "the simulation says we can do a 90/10 if we just do X, someone print up a block and toss it in the wind tunnel and see how it does" type approach so the result tends to be more surgical modifications and use of dead air and less "smooth out the whole thing with fairings".
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?
One of them must be better aerodynamically though, must'n it?
Furthermore Europe has relatively strict speed limits on trucks, which makes aero something of a lesser factor since drag grows to the square of speed: european trucks at european speeds have a pretty significantly higher efficiency than US trucks at US speeds.
And that assumes the speed limits are respected at all, but the EU has required a hard 90kph limiter since 2005, tampering with the limiter is a criminal offense, so is tampering with the (also mandatory) tachograph which would reveal the first.
So while nothing prevents speeding up to that (and it very much happens) going higher becomes extremely dicey.
I fear even that is misleading. Yes, the speed limits on undivided highways are often 55 in the north-east (or even 50 in a couple), but the speed limits on divided highways are all higher, ranging from 65-75 mph. See the two maps on the top right: https://en.wikipedia.org/wiki/Speed_limits_in_the_United_Sta.... I suspect that the majority of truck miles are on divided highways.
I've seen truck speed limits of 55 pretty much everywhere I've been except Texas, though.
But that goes directly against TFA, doesn't it? The final image is closer to the European design than the American one? Or am I misunderstanding the article?
> they are potenitilly safer
Maybe for the occupants, but for everyone else they seem strictly worse, not to mention the visibility much be much much worse, making it a somwhat iffy tradeoff.
The air may be the same everywhere, but roads and safety laws aren't.
No I just meant that drag was a second thought when the regulation was conceived on either side of the ocean. The regulation was not created "because of drag". The main driver was road safety. Efficiency and pollution were secondary. There are other ways to achieve them like improving aerodynamics or power trains, and much of this cost is paid by the freighter alone. This is why speed limits didn't increase as trucks got more efficient and drag went down. Because there's no way to reduce the potential energy of a 40-50t vehicle (or up to almost 90t Finland) travelling at 130km/h.
Again, not relevant.
> The regulation was not created "because of drag".
That is not a claim I made. Please do not involve me in your fights against the ghosts you made up.
Are they? I mean by intuition I'd assume the same, but seems it isn't considered so black and white as far as I can tell, I can find reasonable research pointing both ways, but I'm guessing you're basing that on something more conclusive? Mind sharing the link so I could too read up on it?
TFA literally has NASA doing research and seemingly reaching a different conclusion than "long-nosed trucks are vastly more aerodynamic", seems to be about more things than just the hood, and those can be/are optimized on both variations.
But again, I know little about all of this, but would welcome being educated on it more.
Also American truckers do a lot more long-haul work and American roads are noisier, so they prefer being more insulated from the engine.
There is also suspension between the axles and the chassis which is 99% of the time air on the rear, leaf spring front.
I haven't come across a cab that is suspension isolated from the frame of a conventional, even though the axles are on air. Theoretically as the driver is in the sweet spot of a much longer wheelbase, rather than sitting directly over an axle.
They are very often on a simple suspension. The cab will have a pivoting mount at the front and sit on air springs in the back.
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.
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
I don't understand why you put such a negative spin on this. Who loses when trying to become more energy efficient?