Hi Dan;
Here is my input. In 1990 I talked my partners Ken Logan and Jerry
Jones into trying ground effects for traction instead of lead. We took all
the lead out (about 800 lbs. I think) and I built skirts for the sides. With
the slope on the underside of the car and tapering up from 36 in wide at the
firewall to 40 inches wide at the back end the aero guys at Lockheed
thought the resulting diffuser would produce about 1200 pounds of downforce.
First run Jerry hits a wet spot at about 220 an it swaps ends so fast he
can't catch it. The car went around 5 times, it turns out that the ground
effects worked just great till the car got a little sideways and the airflow
through the tunnel stalled.
Wings and tunnels add traction with a drag penalty and that penalty
increases with the square of the speed. Lead adds traction with an
acceleration penalty but it is constant and doesn't go away when the airflow
is less than ideal. If I were building a streamliner it would be front
engined, front wheel drive to get the maximum weight on the drive wheels.
Aero managed downforce is neat if you have to turn and accelerate at the
same time, we don't.
Jim in Palmdale, who's rocket scientist reputation was enhanced by the above
incident.
----- Original Message -----
From: Dan Warner <dwarner@electrorent.com>
To: <land-speed@autox.team.net>
Sent: Thursday, June 08, 2000 10:33 AM
Subject: Flying Streamliners
> Interesting conversation concerning streamliners. Ken Walky stated that
> there had never been a ground effects streamliner that did not fly.
> Accumulated wisdom could not refute Ken's theory.
>
> We had to define ground effects as a lifting surface on top of the car
> and/or tunnels or some such device under the car(non-flat bottom).
>
> Any comments?
>
> Dan (looking for air) Warner
>
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