In The Tracks...
NASCAR Safety Spotlight:
Why Did Kenseth Flip at Talladega?
April 27, 2009

We all sit down and watch the NASCAR coverage on TV at Daytona and Talladega and they constantly talk about the safety features on the cars to keep the Bobby Allison and Richard Petty wrecks of the past a thing of the past. Then, we see Matt Kenseth in the Nationwide race at Talladega flip violently and catch fire. Why did he flip with all that safety equipment?

Well, it's no fault of NASCAR's current safety equipment. To explain this we'll look at the safety equipment.

First, running down both sides of the car between the tires are the side skirts that block air from going under the car.

Next, on the right side of the car there's a window in the right side/passenger door, but it is inset in the frame to make the air turbulent as it goes up onto the roof. This turbulence pushes the car down instead of creating lift.

Then, on the roof on both sides running front to back is a short metal air deflector, which on the driver side continues as a plastic piece down the rear window.

Finally, in the roof are the roof flaps. The passenger side roof flap is angled so that as the car spins counter clockwise it opens before the car gets turned around very far and the flap then catches the air and slows the car to speeds that aren't fast enough for the car to lift off the ground. The car will continue to spin out, but as it does the driver side roof flap that is parallel to the back window opens to also continue to slow the car to speeds below lift speeds.
The car on the upper right shows the side fender skirt in bright red along the bottom between the tires. The cut out section is the location where the jackman places the jack during pit stops. The lower right car shows the roof rails above and below the number in the bright red as well as the piece down the driver side of rear window also in bright red. You can also see these roof pieces on the car in the lef that is also showing the roof flaps deployed.

So, with all of these safety features, why did Kenseth flip? Simply it was the fact that he spun clockwise as he turned to the right to avoid running straight into the inside wall down the back straight.

Most of these safety features are designed if the car spins counter clockwise as if a car is always turning left in the turns, except at the road courses where speeds are much lower than those that create lift, it is much more likely that the dangerous spins will be counter clockwise spins.

However, the rail on the roof and down the back window that deflects the air on the driver side are the ony real items to stop a clockwise spinning car from achieving flight. Plus, the open driver side window allows air into the car with nowhere for it to escape, which assists in the lifting of the car. The driver side roof flap directed straight backward is designed to work with the other roof flap so you can't angle it opposite the passenger side roof flap to prevent the car from flipping if it spins the opposite direction.

Also, you can't put a window in driver side as in Kenseth's case, the car was on fire and even if the car doesn't flip it can still catch on fire and the driver needs to have a quick exit.

Overall, there's not a whole lot NASCAR can do other than continue to slow the race cars down so that they don't reach speeds that are conducive to achieving flight. However, cars have been getting up in the air since the beginning of racing and the likelihood of preventing it all the time is unrealistic. What we have to be thankful for is the continued safety inprovements that NASCAR has with the HANS (Head And Neck Safety) device, strong roll cage and other driver safety features that protected Matt Kenseth and Carl Edwards at Talladega this weekend, and Michael McDowell last year at Texas after violent flipping wrecks. Notice in the photos of Kenseth's wrecked car above that despite the extensive damage to the front and rear of the car, the structure of the driver area held up while the car rolled and slid on it's roof. The important thing is Kenseth, Edwards and McDowell all walked away from the wrecks uninjured.

In The Tracks...

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