Page 7 - Combined_26_OCR

INTRODUCTION

The recently developed nFn Series Race Charger has considerably lower drag
than any other race vehicle currently campaigning on the NASCAR circuit.
However, potential speed, increases based on drag reduction alone will not
be fully realized unless adequate means of controlling vehicle handling
at the higher speeds are developed* Recent wind tunnel tests and theoretical
studies of the use of aerodynamic control surfaces have been focused on the
development of such a handling capability.

Use of aerodynamic control surfaces on automobiles is not new. Many Land
Speed Record vehicles have been equipped with such devices and considerable
work has been done on the effects of stabilizers, airfoils, etc. on vehicle
handling in cross-winds and during cornering maneuvers.

The recommended. aerodynamic controls package discussed in this report con­
sists of two vertical stabilizers mounted at the rear of the rear quarter
panels with an airfoil section mounted between them approximately 2h inches
above the rear deck. Control of rear lift and front to rear lift distribution
is the primary function of the airfoil section, while the vertical stabilizers
are used to reduce the front to rear side force differential and, to a lesser
extent, increase lift on the right.side and reduce lift on the left side
during cornering. Naturally, all of the control benefits associated with
these devices are- only meaningful if the drag penalties associated with them
are relatively small®