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This video gets a lot of play among traffic safety engineers. All of these downward tapered end treatments such as this or the "Texas twist" guardrail are notorious for launching or flipping vehicles.

Must have been inspired by the Dukes of Hazzard stunts...

This video gets a lot of play among traffic safety engineers. All of these downward tapered end treatments such as this or the "Texas twist" guardrail are notorious for launching or flipping vehicles.

Notorious, yes, but isn't the whole purpose of these tapered ends to redirect the energy of impact up, so that gravity counteracts it... rather than to just slice through the car?

I imagine that these are only designed to be particularly effect up to a certain speed... Once your doing 80+ mph, all bets are off... you're probably going to launch into a bridge abutment or something.

Even so, it always about limiting damage... as once a car is hitting this, its toast anyway. At least it hopefully will stop or slow the vehicle before hitting something worse... at that point, being upside down and slowing might be a blessing over the alternative.