The Kamm research cars

[JulianEdgar]

There's lots of crap often talked about these cars, but even with that, they remain extraordinarily significant.

https://www.youtube.com/watch?v=Q2uLwNq4jZo

[aerohead]

Kamm / Koenig-Fachsenfeld were able to reproduce Walter E. Lay's,1933, Cd 0.12, with an otherwise identical model, excepting for a cambered, aft-body roofline addition, compared to Lay's straight taper, beyond the lead-in curvature.
The 2020 Chevrolet C8, Corvette Stingray uses Kamm's 1935 roofline.

[JulianEdgar]

Originally Posted by aerohead

Kamm / Koenig-Fachsenfeld were able to reproduce Walter E. Lay's,1933, Cd 0.12, with an otherwise identical model, excepting for a cambered, aft-body roofline addition, compared to Lay's straight taper, beyond the lead-in curvature.

I am not sure what you are talking about? But drag figures on small models in the 1930s are notoriously inaccurate, so to use still more of them in support of something isn't a great idea!

[aerohead]

Originally Posted by JulianEdgar

I am not sure what you are talking about? But drag figures on small models in the 1930s are notoriously inaccurate, so to use still more of them in support of something isn't a great idea!

So true! Many, tested later, in superior facilities, returned even lower coefficients than originally published.
If you have case-specific examples, that would be useful.

[JulianEdgar]

Originally Posted by aerohead

So true! Many, tested later, in superior facilities, returned even lower coefficients than originally published.
If you have case-specific examples, that would be useful.

Examples? The drag of nearly every model in the 1930s / 1940s / 1950s has been shown to be grossly inaccurate when later tested. Same for full size cars - with just one or two exceptions. Just look in all the normal references.

[freebeard]

Thanks for covering the golden oldies.

You like #1's esthetics, but I see that picture of the #3 monocoque and think it needs a rat rod treatment — Delete the front sheet metal and do the interior in patina'd bare metal with Mexican blanket seat covers on low-back bomber seats.

[aerohead]

Originally Posted by JulianEdgar

Examples? The drag of nearly every model in the 1930s / 1940s / 1950s has been shown to be grossly inaccurate when later tested. Same for full size cars - with just one or two exceptions. Just look in all the normal references.

If some of the most important research models were ever re-tested, I'm unaware of that.
We know that the Jaray small car returned lower drag at AVA than was originally reported at Zeppelin.
Hucho got essentially identical Schl'o'rwagen results,@ 1/4-scale, as originally reported at AVA 1:1-scale, if memory serves me.
Hucho wasn't shy about Jaray's Cd 0.13 pumpkinseed.
Or Wolfgang Klemperer's numbers from Zeppelin.
Or Lay.
These would be useful investigations.
CUER returned Cd 0.11 at one of the aeronautical tunnels. It's very reminiscent of the 1920-1939 research models.
Kamm's lowest drag car didn't survive the war.

[JulianEdgar]

Originally Posted by aerohead

Kamm's lowest drag car didn't survive the war.

There you go again...

Again, I am not sure if you are being deliberately misleading - or that's your genuine belief.

You said: Kamm's lowest drag car didn't survive the war.

Let me put that a different way: The car that did in fact survive the war proved to have a very much higher drag coefficient than the pre-war tests showed.

To assume, therefore, that the other pre-war data is correct is a bit simplistic.

I am not sure why you pursue this fable that all significant car aero happened in the 1920s and 1930s.

I can draw similar parallels with car suspension eg the work of Messrs Lanchester, Olley and Milliken. They are incredibly significant people, and what they discovered we use every day - but they don't dictate the suspension rates I chose on my Insight. They certainly help inform those decisions, though.

And it's exactly the same with car aero.

Great to know about what the heroes of the 1920s and 1930s discovered, but only within the context of today's knowledge.

[aerohead]

Originally Posted by JulianEdgar

There you go again...

Again, I am not sure if you are being deliberately misleading - or that's your genuine belief.

You said: Kamm's lowest drag car didn't survive the war.

Let me put that a different way: The car that did in fact survive the war proved to have a very much higher drag coefficient than the pre-war tests showed.

To assume, therefore, that the other pre-war data is correct is a bit simplistic.

I am not sure why you pursue this fable that all significant car aero happened in the 1920s and 1930s.

I can draw similar parallels with car suspension eg the work of Messrs Lanchester, Olley and Milliken. They are incredibly significant people, and what they discovered we use every day - but they don't dictate the suspension rates I chose on my Insight. They certainly help inform those decisions, though.

And it's exactly the same with car aero.

Great to know about what the heroes of the 1920s and 1930s discovered, but only within the context of today's knowledge.

1) Excepting the Everling car, the FKFS contructed six ( 6 ) K-form cars.
2) Kamm's personal car was Cd 0.23. A diesel-powered, 4-door, drop-nose, fully-skirted, long rear overhang, with overdrive transmission, and Kamm's patented low-drag engine-bay cooling system.
3) The Landenburg Castle car tested by VW is nothing like it. And as you know, that car had a mutilated belly pan, so it's Cd was corrupted.
3) the only photograph of this car is in HOT ROD Magazine, from 1963. Some of the HOT ROD staff met Kamm in Florida, when Dr. Kamm was consulting on what became the Briggs Cunningham, C4-K Le Mans coupe, which swept the field o the first lap in 1953. ( probably inspiration for Pete Brock's Shelby Daytona Coupe, as Brock studied all the European aerodynamics research leading up to WW-II, when at General Motors ).
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I'll address early Cds elsewhere, as I believe we already have a dedicated thread for that.
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As to 'fables,' all I'm saying is that, the 1920s and 1930s Cds of 'basic' bodies have been verified in modern laboratories, with 'identical' results in some cases. You have used some of them, perhaps unwittingly, in your anti-template thread.

[JulianEdgar]

Originally Posted by aerohead

1) Excepting the Everling car, the FKFS contructed six ( 6 ) K-form cars.
2) Kamm's personal car was Cd 0.23. A diesel-powered, 4-door, drop-nose, fully-skirted, long rear overhang, with overdrive transmission, and Kamm's patented low-drag engine-bay cooling system.
3) The Landenburg Castle car tested by VW is nothing like it. And as you know, that car had a mutilated belly pan, so it's Cd was corrupted.
3) the only photograph of this car is in HOT ROD Magazine, from 1963. Some of the HOT ROD staff met Kamm in Florida, when Dr. Kamm was consulting on what became the Briggs Cunningham, C4-K Le Mans coupe, which swept the field o the first lap in 1953. ( probably inspiration for Pete Brock's Shelby Daytona Coupe, as Brock studied all the European aerodynamics research leading up to WW-II, when at General Motors ).
--------------------------------------------------------------------------------------
I'll address early Cds elsewhere, as I believe we already have a dedicated thread for that.
-------------------------------------------------------------------------------------
As to 'fables,' all I'm saying is that, the 1920s and 1930s Cds of 'basic' bodies have been verified in modern laboratories, with 'identical' results in some cases. You have used some of them, perhaps unwittingly, in your anti-template thread.

You didn't actually address any of the points I made. Maybe read them again? (I've numbered them so you can address each in turn, if you wish):


1. You said: Kamm's lowest drag car didn't survive the war.Let me put that a different way: The car that did in fact survive the war proved to have a very much higher drag coefficient than the pre-war tests showed. To assume, therefore, that the other pre-war data is correct is a bit simplistic.

2. I am not sure why you pursue this fable that all significant car aero happened in the 1920s and 1930s.

3. I can draw similar parallels with car suspension eg the work of Messrs Lanchester, Olley and Milliken. They are incredibly significant people, and what they discovered we use every day - but they don't dictate the suspension rates I chose on my Insight. They certainly help inform those decisions, though. And it's exactly the same with car aero. Great to know about what the heroes of the 1920s and 1930s discovered, but only within the context of today's knowledge.