In article ,
The Natural Philosopher wrote:
Or an aircraft designer. Enough to create a pressure difference big
enough to keep a plane up.

Planes have wings specifically designed to produce lift. Only the most
stupid card designer would use the same effect.

I am beginning to wonder about you Dave.

You aren't Drivel under a new name are you?

Just answering your irrelevances with some of my own...

All of formula 1 is about aerodynamics - using air pressure to produce
lift downwards..

Which makes for inefficiency. It may well help the car to corner faster -
but in doing so will use more energy. You don't get out for nowt.

Air pressure changes are inevitable in any body moving through air. When
these result in turbulence and vortices these become where the energy
goes that causes the actual profile drag.

Skin friction is also an affect, but at car sizes and speeds is not a
huge component.

What dominates low speed drag is a more or less constant rolling
resistance due to tyre deformation: What dominates higher speeds is air
resistance associated with pressure changes and vortex formation round
the bodywork

If it were only tyre rolling resistance, how do you explain 4WD being
markedly heavier on fuel than 2WD?

--
*If you try to fail and succeed, which have you done? *

Dave Plowman London SW
To e-mail, change noise into sound.