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Comment by thematt | Hacker News Reader

I thought we were done with the ugly "covered up rear wheels for electric cars" thing.

It's unfamiliar, not ugly. Give it a few years and you'll think they're perfectly fine, just like we heard endless complaints about "melted" cars when more aerodynamic designs were first introduced.

(partially) covering the wheel doesn't have to be as ugly as it is in this particular VW. I submit the first generation Plymouth Fury as evidence:

http://en.wikipedia.org/wiki/Plymouth_Fury

Ugly or not, covering up the rear wheels can give a meaningful improvement to fuel economy.

An early Saab also had covered front wheels, to improve economy. It was problematic though because it under certain conditions it could get packed with snow and hinder turning.

With wheel no more than a few inches wide, it won't be driving in the snow anyway.

Actually unless you're trying to drive on TOP of feet of snow, narrow is better than wide for normal driving as you cut through the snow and get to the road. Typically people will run snow tires that are 10mm narrower than their summer tires on the same rims.

Curious to see how that could possibly look, I scrounged up these pictures of a 1947 Saab prototype. Beautiful.

http://www.thelocal.se/gallery/news/806/

wow. That, is a beautiful car.

Well, the request was simply to see some data on how "meaningful" the improvement is.

I think the covered up rear wheels are not just a optical gimmick, but safe fuel.

It looks kind of sexy (and expensive)!

Probably the expensive part is true. :(

The car may be expensive, but covered rear wheels are not expensive.

It's hideous; I agree. The prevailing argument here for the covers is fuel economy (i.e. reduced drag). Show me the numbers with and without the covers, but, I'd bet they're not so different that I'd sacrifice the look of the automobile by adding them, especially considering the 250+ MPG claim here.

Here are some stats: 0.4-6.25% http://ecomodder.com/wiki/index.php/Rear_wheel_skirts

It's highly dependent on speed.

Small gains can add up. I had a 75 minute commute for a while and ran some MPG experiments on my truck. Adding a wedge shaped tonneau cover, a chin spoiler, and inflating the tires more boosted my MPG from 18-26. It was ugly so I took them off and got distracted before I built them again. It was much quieter and seemed to "roll" along at faster speeds.

HN is certainly not the place I expected to find a comment criticizing the aesthetics of a useful engineering decision.

I'm excited to see a car that was actually designed up-front with aerodynamics in mind. This isn't the first of course but they're pretty rare. Even for the Bugatti Veyron and Nissan Leaf, where you'd think drag forces would be the first consideration for the body, the overall look was determined first and aerodynamic engineers had to work within those limits.

I don't know about the Bugatti, but think of the use case for a Leaf -- urban commuting and errands. Does aerodynamics matter for city driving?

Here in snow country, the last thing I would want is for my wheels to be covered like that.

Not everything is snow country and it might make perfect sense in warmer or more densely populated places.

There’s no reason why one car would have to be fit for every climate on every continent.

I figured someone would make that comment. I'm just giving one example of why this may not be a good engineering decision. It also makes it hard to access or inspect the wheel/tire in general. You can't just optimize for one thing like aerodynamics without taking into account the big picture (and I personally think aesthetics). I have seen many solar cars and high efficiency cars over the years that are highly impractical because they've optimized one efficiency dimension too far.

Of course you have to take maintenance and aesthetics etc. into account, but depending on your target market and the value you put on fuel efficiency, you can still come to the conclusion that covered wheels are the way to go for this particular vehicle.

Nobody would put covered wheels on some off-road car, mostly because these aren’t exactly known for efficiency in the first place.

Aesthetics have a lot to do with building a successful car. A simple example? The VW New Beetle shares the same platform as the Jetta, but ask 100 men if they would own one.

Sure, but the extremely dismissive tone of "lol ugly" is not at all what I'd expect from a crowd interested in building great things.

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