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Comment by tankenmate | Hacker News Reader

The Model X has such a low centre of gravity that you'd need to be driving almost deliberately to rollover; the only exception to that would be driving the car with negligently low tire pressure and/or overly soft suspension (I always wondered why rollover rates in the US were so high until I realised that cars that ship in America tend to have much softer suspension than they do in the rest of the world).

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This could actually be even lower on the highway as well due to the smart suspension (optional, but common) that lowers the car at highway speeds.

Why are suspensions softer in the US? Is that simply related to the fact that a large slice of the rural market is driving on unpaved roads frequently? I would assume this would be an issue elsewhere in the world also, but perhaps not in Europe.

I don't know that cars in the US necessarily have softer suspension than their European counterparts, but I can attest to the fact that it is not due to the rural population. Much of the rural population will be driving pickup trucks or truck-based SUVs, which have much stiffer suspension than a normal car.

I know that older Cadillac models would have very soft suspension (that's why people refer to them as boats, they take bumps like they were riding waves). I can't attest to that being a factor in any higher incidence of rollovers. If there was in fact a higher percentage of rollover accidents in the US, I would put more money on this being due to the fact that the US really likes truck-based SUVs (Jeep Grand Cherokee, Jeep Wrangler, Chevy Blazer/Tahoe, Toyota 4Runner, etc) with lots of weight really high up. My 1998 4Runner even had a warning sticker saying you can't corner like you would in a car without risk of rollover.

In short, people buy cars they don't know how to drive.

Oh right, I guarantee you this is correct. It's the popularity of high center of gravity cars like SUVs combined with a lack of driving ability. Nice thinking.

There are plenty of cases where you can roll without intending to roll. If you are forced off the road (by another driver, by ice, poor reaction to deer crossing the road, etc), hitting a ditch at 50mph at the right angle will almost surely launch your car sideways. Being hit by another car running a red light could easily launch you sideways as well.

Even with the softest suspension, you usually have to spin out and catch a wheel rim on a curb to get a car to roll over, unless you have really high center of mass (like some non-crossover SUV's, like the 1990s Jeep Grand Cherokee).

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