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Comment by Ballas | Hacker News Reader

Yeah, I fail to see how the car being an SUV is a factor in the article. Would a smaller car have made a difference? It would have needed to be a lot lighter to be stopped by the traffic light. (the influence of mass being linear and that of speed being cubic)

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https://scholar.google.com/scholar?hl=en&as_sdt=0%2C5&q=SUV+...

I've seen numbers showing in pedestrian accidents, SUVs are twice as likely to kill the pedestrian than smaller cars. Nonetheless, I'd rather we just phase cars out of inner cities entirely.

SUVs also tend to have much more powerful engines.

If the accident was really caused by an epileptic seizure (as the media speculate), a smaller car with a less powerful engine wouldn't have accelerated as quickly as that Porsche Macan.

But not all SUVs are Porsches. Plenty of smaller cars accelerate much more quickly than SUVs.

SUVs have higher and steeper fronts that tend to hit directly and relatively high on the body, directly impacting vital organs.

With smaller cars the pedestrian often ends up rolling over the front.

Cars are more designed to have the front crumple, and that makes the influence much less, because less kinetic energy is conserved in the collision.

I don't think there is much of a difference in the crumple zone for a German SUV and a German sedan. Do you have any sources?

Look up "Bradsher Bars." They're designed to make sure in a collision with a car, the SUV frame will catch the car and not overtop it, which would be even worse for the car's occupants. BUt they also mean less crumpling because the bars have to connect directly with the frame.

As others have said elsewhere, it's the height that's particularly important. As I understand it, there are two reasons: taller vehicles are more likely to send pedestrians under the vehicle than over it, and the point of impact is likely to move from the legs (unpleasant but usually survivable) to the trunk (often not).

Obviously, a different mass would make a difference in a wide variety of situations. SUVs don't drive slower than other automobiles. Also, kinetic energy has velocity squared, not cubed.

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