General Motors "Aero X" Experimental Aerodynamic Car, 1981
One of the more notable features of the Aero X was the absence of exterior moldings and the use of flush glass all around the car. This study in aerodynamics represented the latest example of a fuel-efficient car, designed without sacrificing aesthetics or comfort. The hood sloped down in a steady curve and used a unique cooling air inlet under the nose. The wheel covers were flush with the wheels, which were mounted in line with the body sides to give the car a "slippery" configuration. The rear of the body was specifically shaped to let air flow smoothly over it. The car underbody - from the air inlet rearward to the axle - was carefully shaped. A pair of progressive widening wedge forms began under the nose and reached their maximum width at the front of each wheel opening. This insured that the air which was not used for engine cooling was deflected efficiently under the fiberglass car. Aerodynamic tests showed that the wheelhouse space usually required for wheel movements in bumps and turns contributed to overall drag coefficient. In the Aero X, each wheel opening incorporated a unique flexible spacer which smoothed the airflow along the entire body side and permitted all the required wheel motions.
Concept Car Central
Aerodynamic and attractive
There are many aerodynamic features on production cars today that go unnoticed, but in the early eighties the same ideas were visionary.
The fiber glass-bodied Aero X included design features such as flush glass and door handles, a grille-less front with under-the-bumper air inlets for engine cooling, and wheels positioned outward, flush with the body panels. Those features and more would be passed along to subsequent concepts and production vehicles.
As seen in the photo it was fitted with flush wheel covers but what is not easily visible are the flexible spacers that were incorporated into each wheel well. The spacers smoothed airflow around the wheel openings, without interfering with wheel movement.
Although less innovative, another design factor contributing to reduced wind drag (at least when supplemental lighting wasn’t needed) were concealed, pop-up headlights.
Although this is a General Motors (i.e., no specific division) concept, the rear designs shares quite a bit with that of Pontiac’s soon to be released 1982 Firebird and Trans Am (which, anecdotally, was GM’s most aerodynamic production vehicle through 1983).
The Aero X also gave attention to airflow movement under the car as there were wedge-like deflectors under the front end that moved un-needed air under the car and around the tires.
Mike Rosa - autosofinterest.com