Interesting Aerodynamic Cars (Mike Vetter's ETV, also Avion)

[kach22i]

Automobile 2 - Odds and Ends pictures by kach22i - Photobucket

[NeilBlanchard]

The individual parts of the car cannot work like the template does. The rear fenders for example only have air flow that is already been diverted by the forward parts of the car, so applying the template is not illustrating anything like the air flow there.

That is a new view of the Panhard sedan. And it is a very different solution than the Panhard LeMans car.

[kach22i]

Originally Posted by NeilBlanchard

The individual parts of the car cannot work like the template does. The rear fenders for example ......

I have yet to pick up or look at the Hugo book, but scaling down the template for protruding elements seems reasonable.

I'd go so far to speculate that the long 1:5 template ratio may be discarded in favor of a more free-flow 1:3 teardrop ratio for certain situations.

The front and rear wheel blisters/flares are so modest that it's more of a styling statement. I tossed the template over them out of curiosity.

The nose on the other hand is something I've practiced before and think there may be something to it. However, like I already said, I need to refer to those books Aerohead listed for me to read.

[NeilBlanchard]

I found some new images of the CD Panhard LM64:

1964 CD Panhard LM64 prototype 24 Heures du Mans 1964 Charles Deutsch (1 of 2) for sale: Anamera







Here's the "money" shot:





Edit: here's an interesting image:

http://imageshack.us/photo/my-images/6/cd003c.jpg/

[Rokeby]

I note that the rear rudders/vertical wings/whatever are not aligned with the cars fore-aft centerline.

Instead, they form a separated V with the open end pointing forward.

Is this because that's the angle of the slipstream at that point?

[Sven7]

Originally Posted by kach22i

I have yet to pick up or look at the Hugo book, but scaling down the template for protruding elements seems reasonable.

I'd go so far to speculate that the long 1:5 template ratio may be discarded in favor of a more free-flow 1:3 teardrop ratio for certain situations.

The front and rear wheel blisters/flares are so modest that it's more of a styling statement. I tossed the template over them out of curiosity.

The nose on the other hand is something I've practiced before and think there may be something to it. However, like I already said, I need to refer to those books Aerohead listed for me to read.

Would you bend the rules of long division if the ending number were nicer? No, so use the template how it's supposed to be used.

[kach22i]

Originally Posted by Sven7

Would you bend the rules of long division if the ending number were nicer? No, so use the template how it's supposed to be used.

It's supposed to be used as a 3D tool as well. When was the last time you saw someone (other than myself) use it in plan view?

Rokeby, good observation.

I think the vert stabilizers are directing the air in order to get the air to leave in a vee or cone shape. This may cause less turbulence in the long run, not sure though.

Neil, I love that car the more I see it. Thank you for posting the additional photos.

http://s184.photobucket.com/albums/x...%20and%20Ends/

[NeilBlanchard]

Originally Posted by Rokeby

I note that the rear rudders/vertical wings/whatever are not aligned with the cars fore-aft centerline.

Instead, they form a separated V with the open end pointing forward.

Is this because that's the angle of the slipstream at that point?

I think you are right -- if the rear wheel track was narrowed, then the air flow would be more straight toward the back. But I think the air does probably flow up and over the rear fenders.

This car is reported to have a Cd of just 0.13; which is obviously excellent. The top speed of ~250KPH / 155MPH with the 1L 2-cylinder engine would seem to confirm this.

I also found a later version of this car from 1967, called the Panhard CD Peugeot 66C:







Panhard CD Peugeot 66C LeMans 1967 | Flickr - Photo Sharing!

Edit: another variation that is obviously "related" but it has significant differences, called Matra 640:

MATRA-SIMCA MS640 V12 - The tyre drop body of the MS640 V12 was the work of Robert Choulet (°1935), a former engeneer at CD, where he introduced already the rear fins. It was an absolutely revolutionary project. Unfortunately the body, tested in the wind tunel, is slightly deformed at high speed. That is what happens on April 16, 1969, when the car is tested on the straight of Hunaudières (the EN138, closed for traffic that day). The air pression makes that the rear of the car rubs the track surface so that Henri Pescarolo looses control over the car being destroyed. Up to now the car remains the centre of heavy polemics. A group of former mechanics, working together with the 69 years old Choulet, rebuilt the 640, and wishes to prove that Jean-Luc Lagardère was wrong when he refused to let built a new MS640 after the first was destroyed. Fact is that Choulet was very unhappy with that refusal and that by October 1969 he quit Matra and co-operated with Porsche on the aerodynamically 917LH tyre drop body. PICTURE: François Hurel, op.cit., p. 62.

Aha! This is the connection the long-tailed Porsche...

[Cd]

Thank you for posting these latest pics of the Panhard and the more modern version, which I had never seenbefore
Absolutely stunning to look at !
Thanks especially for the tuft test picture.
( I wish the car was in motion though ! )

YKYAEM when you find yourself admiring the side skirting on the trailer of that semi in the background ! )

[some_other_dave]

If you look at the right-rear quarter shot, you can see "SERA" on the base of the right tail fin. SERA is or was a wind tunnel in France (near Paris?) that, among other companies, Porsche used to refine designs for a number of their race car bodies. One of the later iterations of the 917LH (langheck, "long tail") was sometimes referred to as the "SERA body".

Been re-reading "Excellence was Expected" recently.

-soD