Sorry, I forgot to delete the trailer.
Howard
----- Original Message -----
From: "Nafzger" <nafzger@vtc.net>
To: "landspeed list" <land-speed@autox.team.net>; "Skip Higginbotham"
<saltrat@pro-blend.com>
Sent: Tuesday, September 10, 2002 7:02 PM
Subject: Re: Race bike Stability and Safety
> Skip,List,
>
> Following is a quote from the book" The Automotive Aerodynamics Handbook"
> written by Henry C. Landa. This is certain to inspire more discussion.
> page T 9-2 & T 9-3.
> "There are many aspects of vehicle design that can cause inherent or
latent
> instability. Suspension systems in total or by component, excessively
> elastic or springy frames, tires, weight distribution both laterally and
> vertically, and steering geometry can cause unstable conditions to be
> present under certain road and operating conditions. These factors along
> with the aerodynamic design should be incorporated into the vehicle design
> so as to produce stability as a natural condition of operation. To expect
a
> driver to provide control forces simply to maintain stability will
virtually
> guarantee a sub- standard and hazardous performance.
>
> Location of the center of air pressure.
>
> For road/sport vehicles: 25-30% aft of front.
> For modern aerodynamic shaped track cars: 30-70% aft of front.
> For pleasure and business automobiles: 30-50% aft of front.
>
> LONG NOSES AND CROPPED REARS TEND TO SHIFT THE CENTER OF PRESSURE FORWARD;
> extending the tails of sport vehicles enhances their stability. Vertical
> vanes used in conjunction with negative lift foils enhance stability only
if
> such vanes are in the rear, ie., behing the center of gravity."
>
> Remember I'm playing Tom Brokaw now and just reporting the news.
> Howard Nafzger
>
> ----- Original Message -----
> From: "Skip Higginbotham" <saltrat@pro-blend.com>
> To: "Bryan A. Savage Jr" <basavage@earthlink.net>; "DrMayf"
> <drmayf@teknett.com>
> Cc: "Waldron, James" <James.Waldron@CWUSA.COM>;
<land-speed@autox.team.net>
> Sent: Tuesday, September 10, 2002 6:26 AM
> Subject: Re: Race bike Stability and Safety
>
>
> > OK then......weather vane principal. CG is the pivot. How much
"variable"
> > area (force?) to put aft of the CG so that the moment is strong enough
the
> > make the vehicle tend to run into the wind and still have enough weight
on
> > the rear wheel(s) (rear drive) to provide propulsion. It isn't easy to
> make
> > it perfect........I think that it is easy to approximate though. The
> forces
> > would add to the effect of the tires trying to make the vehicle run in a
> > straight line (airplanes don't get this advantage). Principal certainly
> > applies to airplanes and rockets to make them stable....designers seem
to
> > try to get the drag minimized by making the tail small and retain
> stability
> > by adding active control systems. We can't do that.....so......weather
> > vane? How should I do it and stay out of a wind tunnel?
> > Skip
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