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Mercedes is planning to sell cars with a drag coefficient of less than 0.20 within the next five years.

With pressure to build greener cars, manufacturers are again focusing on aerodynamics to save fuel and Mercedes believes there is still a lot more to learn.

The German car maker has just launched the E-class coupe, the world’s most aerodynamic car, which has a Cd figure of 0.24.

Today project manager for the car, Rainer Tiefenbacher, said: “There is still plenty more to co...Read the full article

We shouldn't really be surprised by this.  The cooling requirements (which are one of the biggest causes of drag in the modern motor car) are going to change radically over the next couple of years, especially with the adoption of hybrid and all electric vehicles.

 

TegTypeR:

especially with the adoption of hybrid and all electric vehicles.

Electrical systems need cooling as well.   If anything if you have a hybrid car you've got to consider two different cooling schemes covering maximum for the normal engine and maximum for the eletrical system, even though you hope it will be a mix of both you'll need.

Drag reduction is most welcome though.

A fully electric car requires far, far less cooling than a petrol/diesel or hybrid car though.

Also, Cd alone is of limited value - the 'drag area' or Cd.A is a better 'figure of merit' for comparing different vehicles. Still, not to belittle what Mercedes have achieved.

Twenty years ago when Merc was celebrating its 0.30 Cd, Vauxhall already had the Calibra with a Cd of 0.25 and its taken Mercedes that long to catch up - and they're proud of that?!

The other thing they don't mention is the CdA figure - the frontal area of the car has as much to do with the overall drag as the coeficcient - if the car is big it will have more drag, so reduce the size of the car, not just work on how slippery the shape is!

TegTypeR:

We shouldn't really be surprised by this.  The cooling requirements (which are one of the biggest causes of drag in the modern motor car) are going to change radical

 

Years ago , air intakes were getting progressively smaller , as traditional grills were abandoned . Even the E-type 4.2 litre Jag only needed a modest opening.Then someone invented the under-bumper secondary air intake and all hell broke loose.

You guys have a short memory, forget 20 years ago, 26 years ago the Audi 500 (called 100 in some markets) had a 0.29 or 0.30 CD, it was the most aerodynamic saloon in the world, possibly the most aerodynamic car in the world.

Yup Audi! Many conveniently forget this fact.

GM got to 0.19 with its EV1 in 1996 but as it wasn't offically reseased for public sale and just leased out I guess it doesnt count. 

Mission accomplished by Herr Tiefenbacher, to get publicity for the on-sale start of the E class coupe.

manicm:

You guys have a short memory, forget 20 years ago, 26 years ago the Audi 500 (called 100 in some markets) had a 0.29 or 0.30 CD, it was the most aerodynamic saloon in the world, possibly the most aerodynamic car in the world.

 

 

I thought the original 2.0 litre 8 valve Calibra had a cd 0.26 with the 16v having a 0.29? Or am I wrong?

JontyB:

I thought the original 2.0 litre 8 valve Calibra had a cd 0.26 with the 16v having a 0.29? Or am I wrong?

You're right. And it had tiny wheels too, to help achieve that figure, as did the only Audi 100 to reach 0.30 (the base model). So Mercedes achievement is impressive, despite the usual naysayers ...

Impressive yes, but as per horseandcart's post above, is it being flagged to the press by way of a cheap, green marketing tool? I'm sure if CD was the only thing on their minds they could achieve lower figures...

 

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