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by Darthy 577 days ago
Be aware that for global NCAP, safety ratings are dependent on the vehicle class. If a subcompact car receives 5 stars, this does not mean it has the same probability of survivability in full frontal crash as a large executive luxury sedan that received 5 stars.

In fact, if there was a head-on crash between this car and Mercedes E-Class, and you're planning to be in one of the cars, I would advise you to chose the Mercedes.

8 comments

Hence the "arms race" of ever huger cars, yes. And, if you value your life, don't even think about cycling or going by foot with such cars around...
Yes. Anyone who has worked on conservation of momentum problems in high school physics should recognize this. Even at low collision speeds if there is a large disparity in mass between the vehicles then the lighter one experiences a lot of acceleration.

For an extreme case think of a low speed collision between a bowling ball and a ping pong ball.

It boils down to "delta-V".

In a mismatched collision, the smaller vehicle needs to withstand a higher delta-V than the larger vehicle.

Also, in many cases the bumper heights are mismatched so the larger vehicle's strong structure runs into higher, weaker parts of the small vehicle, further exacerbating the problem.

Which is why I'd like a wedge car made to go under a large car in a front end collision.

https://i.imgur.com/xHWAeR4.png

There are several things you can do to dramatically reduce your risk. Cycle during the day, while sober, with bright colors, with a helmet, and avoiding multi-lane roads. If you do these things you've statistical eliminated most of the risk.

> victim blaming

It's an exercise in reducing risk, not assigning blame.

> the law says I can cycle on those roads

The law can't bring you back to life, but if you want to take the risk that's your decision.

We need to think more game theoretically. Since our courageous cyclist must already have a deathwish to be on the same roads as these vehicles, he should go all in with a vest packed with C4 and ball bearings so that, in the event of a crash (which will cripple him anyway), at least he takes out Starbucks Mom on his way to Paradise.
I would wear the hell out of a helmet shaped like a nitro crate from CTR.

https://crashbandicoot.fandom.com/wiki/Nitro_Crate

If the risk is 100x and you eliminate 90% of it, then statistically eliminating most of the risk still doesn't make it all that great a choice.
If you do as I suggest then you eliminate a lot more than 90% of the risk. 62% of cyclist fatalities weren't wearing a helmet, so that alone is a huge thing you can do to improve your odds. 22% are drunk. 50% are on major roads. https://www.iihs.org/topics/fatality-statistics/detail/bicyc...

I knew I would get responses about "why don't cars just..." e.g. why should I change, they're the ones who suck. I'm not suggesting or opposing public policy changes here. I'm giving practical advice which makes cycling much safer than the statistical average.

If you do all of what I say, it's a reasonably safe and healthy pastime.

> If the risk is 100x

Where does this number come from?

People who bike for transportation, not just fun, sometimes need to bike at night, on less bike-friendly roads, or without high-visibility clothing. It doesn’t seem to me that the sentence for that should be death.
> or without high-visibility clothing.

Please, try to get some high-visibility clothing. The difference in visibility is between hundreds of meters with high-visibility clothing and meters without.

> It doesn’t seem to me that the sentence for that should be death.

Maybe not death but severe injuries. Being visiblevin the night is a game changer.

At the very least wrap your bike frame in reflective tape ("DOT C2 tape" is what you want to punch into Amazon if you're in the US).
Not really an option for people who mainly ride bikeshare bikes (e.g. me). But those have pretty good lights, at least.
Why don't you paint your car fluo yellow and put a big fluffy bumper around it?

Since it's your car that does the killing in an accident, not the cyclist. Right?

"You" is singular as a cyclist. Wearing appropriate gear can drastically improve your (again, singular) safety.

"You" is plural for motorists. A single motorist deciding to own and operate a soft-and-safe-mobile will not affect your (singular or plural are interchangeable here) risk appreciably.

It doesn't mean you're wrong, and you (singular) can pick your battles, but I think I'd prefer to be alive than correct.

With electric bikes there is the possibility of adding safety gear to bicycles since the extra drag can be offset by motor power. Even just the simple example of allowing the rider to wear better, motorcycle-style protective gear would be a massive improvement - since they aren't pedalling so hard. Such gear could be actively heated/cooled as well.
I'd rather be in a small car and hit a tree/electrical pole than in a massive vehicle.
Since the heavier vehicle has higher momentum, it would decelerate slower when hitting a semi-static-object, which decreases the forces on your body. The smaller vehicle would stop much quicker and you would jerk forward. So a heavier vehicle at the same speed would probably be better, all else being equal. And that's neglecting the additional material a larger vehicle typically has that deforms over longer distance than with a shorter car.
>it would decelerate slower when hitting a semi-static-object

You just changed the problem.

Did I? Trees and electrical poles aren’t completely rigid, right?
To a car? Many trees are! They are quite rigidly affixed to the ground.
Yeah, the point was deliberately to show that a small car performs better in such situations.

If you had to change the problem, it shows you were avoiding the uncomfortable truth.

Not really, the car itself is a semi-static object, even if you're driving a block of raw steel.
I did automotive safety and I can assure you, these act as static for all intensive purposes.

Being a skeptical Socrates doesnt change that the momentum is significantly higher, and you arent moving that pole any significant distance.

I'm not sure why there is such a strong denial of reality here. Is it ego?

I'd rather be in a tank and flatten the tree / pole.
I`d rather there were more trees and fast, affordable public transport options.
Interesting to hear the rationale in this choice ?
Might save the tree...
Good point.
awesome, i will only buy ford f150s from now on so i can have the most mass during any collision and thus will never be on the worse end of a collision. is it really american if you aren't screwing over your peers?
you should lookup the size comparison of a sherman tank and a modern f150, it's crazy
I was curious (but also lazy) so I went and checked Wikipedia. According to that source, the newest model of Ford F-150 is the fourteenth generation one, so let's look at the numbers for the top-of-the-line Raptor (or what I assume is the top, I'm not a pickup person). Assuming largest manufactured dimensions in all cases for the truck and smallest for the tank:

Ford F-150 Raptor length 232.6" width 118" height 80.7" curb weight 5,540 lbs.

Sherman Tank length 247" width 103" height 108" mass ("curb weight") 66,800 lbs.

So in terms of size, sure, they're kind of comparable, although in a head-on collision I think I'll still take my chances with the F-150.

Just a thought process.. how bad would a f150 <~> f150 collision be, compared to say VW Golf <~> VW Golf? If everybody went with f150, and the chances of colliding with another heavy one increases right? In the end, the edge is only short lived right?
Should probably go for an F-450 in that case.
I guess this means "vehicle safety ratings" only take into account the safety of those inside the vehicle? In a better world the safety of those outside of the vehicle would not only be taken into account but weighted more heavily, which would mean small cars that are safe for the occupants would get the highest ratings. Sadly we not live in that world.
Pedestrian safety is a factor in the ratings.
They only take into account the safety of those inside the vehicle, assuming they hit a static barrier or have a collision with the same vehicle.
YEs, and so I think higher weight classes of cars should require more licensing and higher fees to own.

For safety, we should be limiting the size discrepancy of vehicles where we can.

In a tragedy of the commons, without top down intervention, people either choose to be part of the problem or part of the solution.
relative rating or not, it has been successful at pushing car manufacturers to make safer cars, at least in the region the article talks about.

recently it has become a selling point to have a 5 star safety rating for cars in the market, which has finally made basic aspects like airbags part of the cheaper trims.

This seems like a clear case for government regulation over libertarianism, because who else holds the interest of this sort of social good at the scale of all cars driving the roads?

The personal moral dilemma here is crazy. Are you willing to risk your own life and the lives of anyone else in your car over the lives of the people in the other car? It's so terrible but you also can't fault anyone individually for choosing a larger car for safety reasons. (Those reasons being, I would prefer to kill someone else than kill myself or others in my car.)

That's why everyone in North America drives or aspires to drive a Ford F150 or Hummer