By on June 20, 2011

Do you think that cars have lost their soul? Nina Tortosa, General Motors aerodynamicist for the Voltec/E-Flex programs, says that cars look more and more alike because “we all have to abide by the same laws of physics. It doesn’t matter if we don’t like them,” Nina Tortosa told WardsAuto.

Mere mortals have to contend with two certainties – death and taxes. Car designers are faced with a third one: Cd, or the drag coefficient.

When I was in advertising, countless engineers tried to explain the drag coefficient (a.k.a. “Cw-Beiwert” – we were in Germany) to me, until one found an ingenious solution: “You want a low one.”

They also told me the secret why the final car never looks like that flashy design study. The wind tunnel, or now rather the drag simulator is the big equalizer.  “It’s a drag,” complained one designer to me, “those damned aerodynamics kill all my ideas.”

Joe Dehner, chief of Dodge and Ram Design at Chrysler, had the same experience: “We, as designers in the late ’80s and early ’90s, were in an organic phase, but aerodynamicists didn’t want organic lines,” he told WardsAuto. “We would take it to the wind tunnel and they would put corners on (it), and (we) would say, ‘You’re ruining my design.’”

Larry Erickson, chairman of the Detroit-based College for Creative Studies Transportation Design Dept. and a former Ford designer, says design doesn’t need to become a victim of aerodynamics. He cites the Opel Calibra, built from 1989-1997: “That car had a killer drag number and looked great.” His advice to students: “Good teams work together to come up with a solution that looks good and is aerodynamic.”

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48 Comments on “It’s A Drag: Does Wind-Tunnel-Vision Kill Car Design?...”


  • avatar
    James2

    It could be argued that aerodynamics can also help inspire car design. Look at Ford of the mid-1980s. They were churning out soulless, boxy Granadas and Fairmonts when the first ‘aero’ Thunderbird came out. Might not have been a great-looking car, but Bill Elliott wasn’t complaining. And everyone knows what the ‘jellybean’ Taurus did for the company.

  • avatar
    panzerfaust

    In my opinion most car designs lost their soul a long time ago. Cd is important but it becomes a pressing necessity because of safety standards, CAFE standards, etc. that are constantly pushing for better economy whilst forcing manufacturers to make heavier cars. And really if asthetics are what we as consumers are interested in, then it isn’t that the car is very aerodynamic that catches the eye, but that it LOOKS aerodynamic. The big American domestics of the 50’s and 60’s undoubtedly have a poor Cd-at least compared to today, but the looked like they were slippery. Beauty can also be found in the utter simplicity of a design, its lack of pretentions as much as sophsitication. The desings of early model Japanese imports to the US still hold up today because they weren’t trying to be something they were not. Good teams should work together to find a good looking design that works; but don’t they still have to run the gauntlet of Corporate approval? What if the boss’s boss says ‘yeah it looks good but it doesn’t look like a Ford/Chevy/Dodge/Toyota, we need to keep the brand design DNA, change it.’ I suspect a lot of compromises get made there too.

  • avatar
    CJinSD

    In my opinion, pedestrian crash standards have had a far more negative impact on styling than efforts to improve aerodynamics. There have been many cars improved by their pursuit of aerodynamic purity, but no car’s looks are improved by raising the hood line and blunting the front fascia.

    • 0 avatar
      SVX pearlie

      The Audi R8 still manages a low nose.

      But yeah, crash standards have changed everything.

      • 0 avatar
        CJinSD

        The Audi R8 doesn’t have an engine between the front wheels. If it had one, there would need to be space between the hood and the engine to provide crush space when a crash test dummy bounces off it.

    • 0 avatar
      geozinger

      @CJ: I agree 100%.

      Now everything (in the US) looks like it has the nose of a freakin’ SUV.

      Ugh.

      • 0 avatar
        MoppyMop

        Now everything (in the US) looks like it has the nose of a freakin’ SUV.

        Probably because most mass-market cars share platforms with some sort of CUV now, and SUV design elements are making their way into cars to lure in SUV drivers as well as those who fear getting hit by them and want a lot of steel around themselves when they do.

        Pedestrian safety regs aren’t the problem. For starters, they’re Euro-only (for now), yet cars that are unique to the US market are often among the worst offenders in terms of hood/beltline height (think Taurus, or USDM Accord). Since the gap between the hood and the engine is the biggest factor in pedestrian safety, cars with engines that aren’t very tall (like boxer engines) should be able to meet the standards while providing the ’86 Accord-esque visibility we all know and love, yet the latest Subarus aren’t really much better than the competition in that regard.

      • 0 avatar
        CJinSD

        articles.latimes.com/2011/feb/24/business/la-fi-court-autos-20110224

        Supreme Court OKs lawsuits over cars’ lack of best safety equipment
        The ruling reverses California court decisions in the case of a man’s claim against Mazda that his wife would have survived a crash if her seat had a lap and shoulder belt, not just a lap belt.
        February 24, 2011|By David G. Savage, Los Angeles Times

        The Supreme Court reversed course and ruled that the nation’s automakers can be sued for failing to install the most-effective safety equipment in their vehicles.

        The unanimous decision Wednesday clears the way for a California man to sue Mazda Motor Corp. because his family’s 1993 minivan did not have a lap and shoulder belt in a middle rear seat.

        —————————————————-

        What does this have to do with hoods? It means that automakers can’t afford to meet safety requirements in some markets or with some new models while not incorporating the technology in other new models without opening themselves up to lawsuits.

      • 0 avatar
        MoppyMop

        They haven’t actually won yet, and all of these cars were designed before that court decision anyway.

      • 0 avatar
        CJinSD

        The accident happened in 2002. This has been in the courts for years with the prospect of it becomming a binding precedent influencing corporate legal departments ever since they found a judge who would hear it.

      • 0 avatar
        MoppyMop

        Euro NCAP first started testing pedestrian safety in some form in 1997, yet go down the list of 2002 and newer cars they’ve tested and you’ll find plenty of cars that don’t score well. If manufacturers were scared of getting sued for not aiming for a higher standard of safety than was required by law, they sure weren’t showing it.

    • 0 avatar
      Acubra

      +1.

      Not to mention how sight lines for shorter drivers suffered through this.

  • avatar
    probert

    citroen ds19 – 21. Now quit your whining and get to work.

  • avatar
    toxicroach

    That Calibra is in the running for the blandest car I’ve ever seen.

    • 0 avatar
      mike978

      In my opinion and from sales charts at the time the Calibra was a well regarded car and design. Much better in person than some small photo.

      • 0 avatar
        CJinSD

        The Calibra in 1989 top of the line roll-out trim was pretty special for the day. Being a GM car, it lost its purity and distinctiveness through detail changes and added dress up packages during its production run.

      • 0 avatar
        Acubra

        Yup. Great design outside.
        But it suffered from a low grade and clumsy Vectra-derived interior and chassis setup. Reliability and longevity were also typical Opel of the time (very average).

  • avatar
    Philosophil

    Drag sucks. (Can I copyright that?)

    If I was a designer, I would have that on my t-shirt and would then simply take it on as a challenge. The best designers/artists are those who can make the most out of the materials/constraints they have to work with and within.

  • avatar
    Zackman

    Cars indeed began to lose their “soul” style-wise with the advent of safety standards, especially with the death of the pillarless hardtops, but the real reason is that the beancounters moved in and took over and de-contented (read: “bright trim”, side badging) the cars to death and forced them to lose their “flash” – that eye-appeal that is all-important to many buyers including this one. Of course this didn’t happen overnight, but the blandness really set in by the mid-to-late 1990’s when much of the “chrome” or bright trim that distinguished the styling largely disappeared.

  • avatar
    Chicago Dude

    Are there any car designers out there that do not yet know that wind tunnels exist?

    These guys are supposed to be professionals. If Chevy asks for a mainstream automobile, they should be able to design a nice mainstream automobile.

    Do car designers express shock when told that factory-standard 26″ wheels are not economically viable on an econobox?

    • 0 avatar
      SVX pearlie

      “If Chevy asks for a mainstream automobile, they should be able to design a nice mainstream automobile.”

      Have you seen the new Cruze?

      It’s a nice mainstream automobile with a Chevy grille, Camaro taillights, and a little sculpted detail to break up the flat areas.

      • 0 avatar
        CJinSD

        I don’t think he meant is an an attack on the new-to-USA Daewoo Lamcetti. A better example would be the Chevy Volt. Remember the show car? It had improbable side glass, which became black tape on the production car. It had obvious RWD architecture, which had no future beyond the show car. It had wheels of massive diameter, something only Fisker would spec on a car that supposedly makes a conservation argument. It made a big splash on the show circuit, and the ignorant masses were impressed. It also had no production future, nor did the design embody ideas of any production use. It did set people up to be unimpressed by the Volt that did reach production though, which looks like a Prius that someone tried to give a family resemblance to the useless show car.

      • 0 avatar
        SVX pearlie

        Wow, you never miss a beat to bash GM, eh?

        Let it go, dude.

      • 0 avatar
        CJinSD

        That’s hilarious, particularly when you jumped in to champion the Lacetti after Chicago Dude merely made a point about design presentations that don’t consider production realities.

      • 0 avatar
        SVX pearlie

        WTF? Where is the “Daewoo” badge, the “Laecetti” badge?

        I’m not “championing” anything. The Cruze is merely an example, and perfectly fine for what it is – a mainstream car. It’s styling is *exactly* what one would expect for the car, and it’s got a decent Cd number. Nothing too bold, mind you, because it’s for the mainstream.

        One could just as easily look at comparable Hyundai & Kia competitors. Similar drag and family-friendly shapes in a neatly corporate-shaped & styled body. They’re equally good examples as well.

        Give it a rest.

      • 0 avatar
        CJinSD

        The Daewoo Lacetti badges are in plain sight in South Korea, where the car was designed and first built by Daewoo. Does putting different trim on it make it a new car? We’re talking about a car introduced in 2008. You’re holding it up as a symbol of Chevrolet design. Google images of the Daewoo Lacetti Premiere. You’ll see just why your tangent here is not an effective defense of Chevrolet’s designers, particularly when it was totally unnecessary to show off the emporer’s new clothes based on a comment that applies equally to most car designers. I chose the gestation of the Volt to illustrate the absurdity of design at is practiced today, because it is one of the most egregious examples of a design proposal that didn’t have any basis in function or production realities.

      • 0 avatar
        SVX pearlie

        Dude, as I originally quoted the OP:

        “If Chevy asks for a mainstream automobile, they should be able to design a nice mainstream automobile.”

        The OP used Chevy as the reference OEM, and the Cruze is merely the most recent car to come out from them.

        And like it or not, the Cruze is as thoroughly mainstream as can be.

        The notion that Chevy didn’t have a hand in the design is simply foolishness on your part. Perhaps if it were designed by and for Korea, only, you might have half a leg to stand on. However, in reality, it’s a global car, designed to global specifications. The fact that the initial build and shakedown was done in Korea before the US shouldn’t be held against GM.

      • 0 avatar
        CJinSD

        caranddriver.com/news/car/08q3/2011_chevrolet_cruze-car_news

        “The Cruze was engineered at GM’s Russelsheim, Germany, development center, and was designed in Korea by GM Daewoo. The car will be assembled in plants around the world, including the U.S. and Mexico, various parts of Europe including Russia (GM is building a new plant in St. Petersburg), South Korea, and Brazil.”

        Chevrolet didn’t get a mention in the development phase, not from Car and Driver, not from Wikipedia, not from Edmunds. Maybe GM do USA stuck on the crossbar grill. At least the result of Daewoo designing the car seems to be enough for reviewers to give the Cruze a pass on having a lower cost version of the Cobalt’s platform under its Korean skin.

      • 0 avatar
        geozinger

        @CJ: I’m with SVX on this one. You’re being argumentative to the point of being obtuse. I wonder if people on other forums discuss the huge and noisy American-designed and -spec Honda Accord in dismissive fashion as you do the Cruze. Probably not. I would guess they have other things to discuss.

        Your own post points out that the car was engineered by Opel and designed by Daewoo. So exactly how does this make it a Daewoo? (Or an Opel for that matter?) GM is doing the same thing that VW, Toyota, Ford and other global carmakers do, coordination among all of their assets worldwide. What do you have against Koreans? Lots of other folks really seem to like their Korean cars.

        Also, the Cruze sits on a Delta II chassis, not a “lower cost version of the (Delta I) under it’s Korean skin”. Why the perjorative reference to ‘Korean skin’?

    • 0 avatar
      CJinSD

      Amen, Chicago Dude. Designers who use wagon wheels and exaggerated proportions that will, and never should, reach production in order to make their designs appealing should not have jobs as designers.

  • avatar
    chuckR

    One look at an SR-71 shows aerodynamics and style aren’t incompatible. (But no pedestrian standards and precious little bean counting with that.)
    The VW pictured would have fit right in during the 1930s for streamliner testing.
    There are treatments that can reduce drag by decreasing the boundary layer turbulence – Sumon Sinha had a paper – SAE 2008-01-2602 – claiming up to 15-30% or so fuel economy improvement in big rigs, reduced to 4% if the treatment is applied only to the tractor. And the rub is that the treatment is fragile and must be kept clean. Similar treatments have sometimes been used on match race sailboats like the America’s Cup yachts, but those are maintained a little different than most of us treat our cars and trucks.

  • avatar
    stuki

    Even without wind tunnels per se, the higher speeds car travel at today, and the higher expectation of quiet at those speeds, would move design in the same direction.

  • avatar
    FleetofWheel

    For non-sports or performance cars, form should follow function.

    The function of a passenger car: full size humans sitting in ergonomic comfort and easily viewing the world around them through the windows. This is more important than a low drag coefficient.

  • avatar
    DC Bruce

    C/d always gets the ink, but, in fact there are two numbers which matter; and C/D is only one of the them. The other number that matters is frontal area. C/d simply expresses the drag generated by the DUT with a flat surface (“barn door”) of the same area. So, a car with a c/d of 0.3 generates 30% of the drag of a flat surface of the same frontal area. Theoretically, it would be possible for a big SUV (with a big frontal area) to create more drag than a small sedan, even though the SUV has a better c/d. Similarly, it would be interesting to compare the drag of a fairly upright sedan, like the Chrysler 300, with a sedan that is lower, even though the two may have the same c/d.

    It would be interesting to compare the percentage decrease in fuel economy with increasing speed — say from 40 mph to 80 mph — of a big, though aerodynamically efficient SUV and an aerodynamically efficient sedan with a small frontal area (like a Prius).

    • 0 avatar
      SVX pearlie

      You’re talking about Cd (shape, ignoring frontal area) vs CdA (true drag for the actual size).

      A bicyclist has a Cd of about 1.0. A SUV has a Cd of about 0.5.

      A SUV has much larger frontal area (A), so the SUV CdA is worse than the bicyclist.

      You can do a similar comparison between a small, high-drag Caterham (Lotus) Seven and a much larger, aero-bodied sedan like a Volt / Pious.

    • 0 avatar
      Zackman

      “It would be interesting to compare the percentage decrease in fuel economy with increasing speed — say from 40 mph to 80 mph — of a big, though aerodynamically efficient SUV and an aerodynamically efficient sedan with a small frontal area (like a Prius).”

      @DC Bruce: I put forth a rhetorical question a few months ago, that it would be nice to see the “suggested” ideal cruising speed of every vehicle based on that vehicle’s drag co-efficient, so you know whether you were getting the maximum possible fuel economy driving at a constant 60, 65, 70, 75 mph or so. Of course, how much weight the car would be carrying at a given time would impact any figures, but it could be based on a full tank of fuel with a driver and a passenger and a target weight combining passengers and fuel of say, “X” number of lbs. above curb weight.

    • 0 avatar
      colin42

      Wow I’m amazed I had to read 80% of the comments before anyone mentioned frontal area. Top marks to DC Bruce (& SVX pearlie)

      Anyone who studied any fluid dynamics should know that the simple form equation for aerodynamic drag force

      = 0.5 x Density x Velocity^2 x Area x Cd

    • 0 avatar
      HiFlite999

      Yep, the whole C/d thing ignores it being a multiplier in the net drag equation. Frontal area is just as important. It also ignores that proper aero design has to incorporate appropriate lift (or downforce) distributions, plus make allowances for sidewinds. This will often increase measured C/d. The original Honda Insight, while having a very low Cd (and frontal area) also generated a lot of bad press for lousy handling at speed and in crosswinds.

      • 0 avatar
        SVX pearlie

        Crosswind stability has been an issue for most aero-bodied cars. Like an unflyable airplane, the Cp (center of aerodynamic pressure) can move too close (or ahead!) of the Cw (center of mass), leading to very low crosswind stability (or instability!).

        To fix this, we need more Audi R18-like cars with giant wings running to the rear!

        Or, at least big, Caddy-style tailfins…

  • avatar

    Styling went south after the ’60s. If C/D is really cutting the heart out of nice styles, then the stylists need to learn more about what makes a car have a good C/D so that they can go with the flow instead of having the flow wash the style away. But I suspect that most of today’s stylists just aren’t nearly as good as Harley Earl et al.

  • avatar
    Zarba

    Alfa Romeo 4C.

    Or for that matter, 1960’s Alfa Romeo Giulia Berlina.

  • avatar
    ttacgreg

    I can cite a sort of a reverse case personal experience. In ’03 when i got my 2.0 4-cyl 5 speed manual 3000 lb Suzuki Vitara 4 door, I still had an ’87 3200 lb 3.0 v-6 4speed automatic Mercury Sable.
    On two consecutive days I made the same 180 mile round trip interstate run in each vehicle. This was done at 10mph over the speed limit, thus 75 and 85 mph cruising. I fully expected the 30+% smaller 4-cyl in the lighter vehicle would get the better fuel economy. It was no contest, the Sable won by about 5 mpg.
    Aerodynamics would seem to be the best explanation for this difference.

  • avatar
    ttacgreg

    cancel edit

  • avatar
    M 1

    I don’t know what the Italia’s CD is, but I suspect it’s good, and it’s still sporting homewrecker good-looks.

    The obvious solution is to make everything mid-engine. Problem solved.
    I will post my forwarding address for royalty checks later this afternoon.


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