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by windexh8er 2503 days ago
Source?

A minivan has a higher center of gravity so in an example where a minivan is cornering aggressively, say to avoid a collision, the rollover likelihood is higher than that of a sports car. As I understand it safety ratings are generally after occupancy protection and aren't concerned with the class of vehicle which goes against what you've claimed.

From the NHTSA website [0]:

"Can I compare vehicles from different classes?

Side crash rating results can be compared across all classes because all vehicles are hit with the same force by the same moving barrier or pole.

Rollover ratings can also be compared across all classes. Frontal crash rating results can only be compared to other vehicles in the same class and whose weight is plus or minus 250 pounds of the vehicle being rated. This is because a frontal crash rating into a fixed barrier represents a crash between two vehicles of the same weight."

And again they are, generally, looking for impact to occupant, for example for the "Side Pole Crash Test Scenario" under "Test Details" they are looking at "Evaluation of injury to the head, chest, lower spine, abdomen, pelvis".

Just because a sports car is a different class of vehicle does not make it inherently less safe. The driver input can change that for any class of vehicle.

[0] https://www.nhtsa.gov/ratings

2 comments

> Source?

A minivan weighs over 4500 lbs, while a sports car probably weighs 3000 lbs. In most collision situations, the heavier car is safer.

Frontal collision tests (and frontal overlap tests) are against stationary objects. So a minivan is tested with 4500+lbs of weight, while a sports car is only tested with 3000 lbs of weight.

Some tests are weight dependent. Others have a static weight.

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I know some friends who survived getting hit by a bus. Riding in a 5000lb+ vehicle helps in these situations. There is a huge degree of safety that is afforded by just having a heavier vehicle.

While that's a great anecdote it's not a source. We could counter your argument by saying that the power to weight ratio of large vehicle is less than that of sports cars. Also because of softer suspensions not tuned for aggressive handling makes for vehicles that get into more crashes due to characteristics that make them worse with regard to stopping before a crash, unable to accelerate out of a compromising situation, or at at odds with a much higher likelihood of rollover due to aggressive maneuvering.

As an aside I have lots of friends who own fast cars who haven't gotten into accidents by avoiding them. Thankfully they were driving lighter vehicles.

I won't berate survivorship bias here.

> As an aside I have lots of friends who own fast cars who haven't gotten into accidents by avoiding them. Thankfully they were driving lighter vehicles.

And we all have friends who regularly avoid accidents in motorcycles. The difference is that you HAVE to avoid an accident to survive them, especially for motorcyclists (the extreme case of smallest but most agile vehicle). While if you're in a big car, you can have an accident and survive.

Its a very big difference. If you ever are a bit tired or distracted, the "trust my reactions to save me" technique will fail.

But if you're tired / distracted, but armored up in a 5000lb or 6000lb vehicle, you'll probably survive whatever hits you.

The survival rate of 18-wheelers (even when they're distracted and tired from driving 10+ hours a day) is quite high. Multi-ton armor just makes things safer.

He's right that heavy vehicles are statistically much safer across the board. If you search for list of cars with lowest accident fatality rate it's almost all giant trucks and SUV's.

You're heavier than the cars around you which helps a lot, but the extra weight also smashes through a lot of obstacles.

> As an aside I have lots of friends who own fast cars who haven't gotten into accidents by avoiding them.

As in driving aggressively and avoiding accidents they were about to create ? Statistically most accidents are rear ends and side collisions, both of which you most likely won't see coming with enough time to react let alone move your car. And getting plowed by an SUV when you're sitting in a sport car means your head is on the absolute worst position you could think of.

Bikers say the same "I'm small, agile and fast, no accidents for me", yet they're disproportionally represented in crash stats.

You're example assumes everyone is the victim. Except that all side collisions and rear ends could be avoided by the stiking vehicle stopping faster. Which vehicles are statistically more often found as being the striking vehicle? It's likely that larger vehicles which can't stop quickly are. And in your example you use an SUV as the plowing vehicle, probably because it's mostly assumed you'll be hit by that type of vehicle, partially for the reasons I just stated.

Again, with the biker statement, since you'll never find a data set that would show accidents avoided on the particular vehicle there's a huge swath of underrepresentation of the reality. And one can argue proportionally bikers are in more crashes because there are less of them overall on top of the fact that most drivers of cars and trucks do not pay considerate attention to smaller vehicles.

And finally my comment about the "friends with fast cars" was a tongue in cheek response to the fact that the parent I was replying to made a large jump by saying SUVs are safer because of size and weight.

> Except that all side collisions and rear ends could be avoided by the stiking vehicle stopping faster

Or you know, not being on distracted autopilot: https://www.theguardian.com/technology/2016/jul/01/tesla-dri...

People get distracted, and when they're distracted they'll crash into things.

Are you implying distracted driving is unique to only Tesla vehicles? The link you posted implies that, and then you immediately generalize your argument.
If we're actually talking about Tesla sports cars here, Model 3 weighs 20%-30% more than 3000 lbs. Model S weighs 4,700 lbs.
Not sure about all the downvotes here, seems like big/heavy car = better. https://www.technologyreview.com/s/413018/laws-of-physics-pe...
Big has benefits for the occupants in terms of larger crumple zones etc, heavy does not. What’s important is jerk and acceleration not your final velocity.

Electric cars actually weigh more due to batteries, but that’s not particularly helpful.

>Side crash rating results can be compared across all classes because all vehicles are hit with the same force by the same moving barrier or pole.

That is incorrect. Your statement is only true in the case of single vehicle inelastic collisions, which is the only type tests NHTSA conducts.

No, actually you are incorrect.

What I wrote is in quotes and directly taken from the NHTSA site. Those are not my words. Try taking a look at the site first.