Well, I was once a high school physics student, and I've also built roads. This assumption is the root of a fatal error is this goof's analysis: </font><blockquote><font size="1" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">quote:</font><hr /><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">For this example, we will consider a vehicle turning in a circular course, to the right, approximately like circling clockwise in an intersection, with a circle radius of 20 feet. </font><hr /></blockquote><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">The almost universal standard for a residential, thoroughfare, or arterial intersection for the radius to BACK OF THE CURB is a radius of 25'. To turn with a radius of 20' means you're off the pavement on the inside of the curve with ALL FOUR WHEELS! To attempt a turn in a right angle corner at 25mph is total driver insanity, and you deserve to die. KevinC makes another salient point about the coefficient of friction. F1 cars get insanely high coefficients of friction by artifically increasing their downforce with aerodynamic aids like wings and specially shaped underbodies that push or suck the car to the pavement. In the late 60's, Jim Hall's Chapparals used a second engine to run a fan to suck the air from under the car, and contained that vacuum with ground rubbing skirts, to achieve the same effect. The dunce uses what looks like a sane speed of 25mph in his example, but as he says in his first paragraph (though clouded in disguise of other problems you "might" - translate as would - encounter as you entered the inevitable slide) an unintended off road expedition is in your future, probably followed very shortly by an instantaneous decelleration caused by a fixed object.
The suv would most likely understeer right thru the intersection, rotating slowly to the right, until the wheels encountered a curb or soft dirt and did in fact roll, all because of the initial driver error of too much speed for the corner.
I was in a hurry, pushing the FJ55 Cruiser (a VERY top heavy beast) down an unfamiliar road in the dark. I entered a corner at what appeared to me to be a high but doable speed, and the corner turned out to have an off camber (tilted to the outside) decreasing radius (gets tighter as you go around). The fronts broke loose first, and I came off the power and dabbed the brakes to transfer weight to the front to get some bite, and as the rears unloaded in that maneuver, they broke loose, and I slid 3/4's sideways around the corner, staying on the pavement all the way. My tires were properly inflated, so they kept thetread on the road instead of rolling it under and losing most of their bite or tearing off the bead and digging the rim into the asphalt.
I'm sorry, but all this is too reminiscent of the Audi "unintended acceleration" cases, where idiots mashed the gas instead of the brake, and claimed the car just "kept going faster no matter what I did".
I have said before and I say it again. If you roll your SUV, it's YOUR FAULT. You didn't keep your tires aired up, or you drove it too fast for conditions or the maneuver attempted, or you failed to properly anticipate the stupidity of those on the road with you, and didn't keep an escape route open. If that hurts your feelings, it's too damn bad. "To suffer ove the sensibilites of fools is to be a fool yourself." Maybe you'll quit driving and I'll have one less idiot to worry about.
