Originally Posted by chuck65
This is something that will blow your mind. I saw a show on PBS I think it was Nova, that dealt with the handling of Indy cars and the wings that they use on the front and back. They must be adjustable to get just the right amount of balanced down pressure. Too much or too little on the front leads to serious steering problems, understeer and oversteer.
Here's the really cool part. (Is "cool" a scientific term. Ha!)
The Indy car, at track speed, over 200 MPH, has so much down force on the car from the wings, that if physically possible you could turn the track upside down and the car would stay on the track.
Thanks to all of the above responses I now understand the differences between a spoiler "spoiling" the airflow to eliminate lift and a wing creating down pressure.
Maybe this Nova program is available on DVD.
A Formula 1 car can also theoretically be driven on a ceiling due to downforce created by it's wings.
The wings on F1 cars, etc are highly adjustable and set to different angles depending on the track. Tracks with very long, high speed straights (Monza) are considered low downforce circuits so the wings are set flatter to reduce drag and increase speeds on the long straights. Tighter tracks (Monaco) are considered high downforce tracks so the wings are set at such an angle as to maximize downforce. Top speeds are generally much lower so there is no speed penalty for such a setting. Watch a Formula 1 race and you can tell by the angle of the rear wing whether they are on a high or low downforce circuit - on a high downforce circuit the wing angle is so steep you can easily read the sponsor logo on the wing when viewed from in front of the car. On a low downforce circuit the wing is so flat you need be above the car to read the sponsor logo!
A couple of the greatest examples of aerodynamic wizardry were the Chaparral sports cars and Brabham F1 cars that made use of a large fan to suck air out from under the car and greatly increase downforce. The Brabham F1 cars ran a single race (and won it) before being banned. I've heard that sitting in the pits in neutral, if the driver revved the engine so that the fan spooled up, the car would drop 3/4" just sitting there!! Imagine a mechanical failure of that fan halfway through a highspeed corner!!