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How well do cars do in crash tests they're not optimized for?

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Re: How well do cars do in crash tests they're not optimized for?

#231

Post by tpmx »

JoeAltmaier wrote: post #187
tpmx wrote: post #183

Earlier quoted context omitted.

I think you're on to something. First: there's vehicle-to-barrier crashes (think trees, etc): Having a vehicle with a large well-designed crumple zone seems obviously good from a survivability POV. Second: there's vehicle-to-vehicle crashes: Is it really a zero-sum game? If a small car crashes head on with a large car, will the people in the small car suffer worse than if they crashed into another small car? To what…

To an amazing degree. In the limit, the large vehicle proceeds nearly unimpeded and the small one is a ball of tinfoil.

I mean, that makes sense if we assume that cars are sphere-shaped with consistent density. Of course, they aren't.

I guess what I was looking for was actual data, not assumptions.

Re: How well do cars do in crash tests they're not optimized for?

#232

Post by sukilot »

zip1234 wrote: post #186
YetAnotherMatt wrote: post #83

Earlier quoted context omitted.

For almost everyone 18-40 year old, driving less is one of the healthiest decisions you can make. A little nitpick: Motorcycling, cycling, and walking are all significantly worse than traveling by car. If this interests you, it's possible to find a lot more interesting research by searching for "microlife" and "micromort".

Motorcycling, cycling, and walking are all significantly worse than traveling by car. Is this because of the chance of getting hit by a car?

Yes, but morticians don't care whose fault it is.

Re: How well do cars do in crash tests they're not optimized for?

#233

Post by BurningFrog »

throwaway0a5e wrote: post #185
BurningFrog wrote: post #174

Earlier quoted context omitted.

Transgender icon J Edgar Hoover did the same. If it was for safety or because he hated lefties is not clear. https://www.nytimes.com/1975/05/27/archives/exagent-says-hoo...

>Transgender icon J Edgar Hoover Citation please. This is the first time I've ever heard him called that. There was some speculation he was gay but nothing conclusive AFAIK. In any case he's one of the last people anyone should pick as a positive representation of their group.

The cross dressing claims are pervasive but not very substantiated. So we can all believe what we want.

I was just trying to be witty when telling a story. Not make any grand statement about anything.

Re: How well do cars do in crash tests they're not optimized for?

#234

Post by nimih »

jacquesm wrote: post #149
nimih wrote: post #139

Earlier quoted context omitted.

On the other hand, when I'm cycling, I'm typically not moving at >15 mph or so. When I'm walking, reduce that to 3mph. That seems like it would do a lot to counteract the car's crumple zones and airbags in terms of severity of injury. In fact, once you take into account severity, the GP's claim seems extremely suspect: maybe the chance of any injury on a bike or by foot is higher, but I'd be skeptical of claims that…

I knew a lot more people that died cycling than I knew people that died in car accidents. And all of the cyclists got hit by vehicles.

I'm in the opposite situation, personally. Irregardless, the point I meant to convey is that I'm able to talk myself into both the original claim and its converse, so it's probably better to actually point to a statistical study than try to provide a causal explanation, no matter how compelling.

Re: How well do cars do in crash tests they're not optimized for?

#235

Post by AgloeDreams »

ghaff wrote: post #35
dangus wrote: post #27

Earlier quoted context omitted.

The way to make yourself safer is to move to one of the few American cities and towns with walking and transit-oriented development. Seriously! You'll spend a fewer hours in the car risking car accident death. A family can easily downsize to one car or less. You'll also spend more time getting light exercise by walking to the bus/train, walking to the store, walking for enjoyment. You'll also save from no longer buyi…

I think it's hard to generalize that living in Manhattan without a car is safer and healthier than living in, say, Vermont with one--especially if you rent cars for weekend and other vacations. Depends of course on location, lifestyle, commute, etc.

Especially with pollution, however there are also social implications that can change your mortality rates. for example a low stress job in NYC could have great social payoff as you are surrounded in a world with anything and everything. Want to play ping pong with random people? Do it! Vermont is extremely isolating unless you are in Burlington or such.

Re: How well do cars do in crash tests they're not optimized for?

#236

Post by Gibbon1 »

t_serpico wrote: post #220
wscott wrote: post #30

The article reminds me of a story from a friend that was an engineer at a major water heater company. Modern electric water heaters are already fairly efficient, but every model gets tested by the government to be given an efficiency rating. The test consists of replacing the anode with a rod that has a series of temperature probes to measure the water at different levels in the water heater. Since water would form l…

Out of curiosity, why would the water form layers of different temperatures?

I think because with a modern water heater especially electric models the heat loss is so low convection often stops completely. So the water in the tank doesn't mix. I think you can get situations too where the water at the level of the heating elements gets hotter and hotter and the water away from it gets cold. My water heater strongly suggests adding a mixing valve for that reason.

Re: How well do cars do in crash tests they're not optimized for?

#237

Post by nimih »

zodiac wrote: post #154
nimih wrote: post #139

Earlier quoted context omitted.

On the other hand, when I'm cycling, I'm typically not moving at >15 mph or so. When I'm walking, reduce that to 3mph. That seems like it would do a lot to counteract the car's crumple zones and airbags in terms of severity of injury. In fact, once you take into account severity, the GP's claim seems extremely suspect: maybe the chance of any injury on a bike or by foot is higher, but I'd be skeptical of claims that…

You can cycle at 15mph and have a car crash into you at a much higher speed

Yes, exactly: there would seem to be factors that both increase and decrease the risk of both activities, so the relative danger of each one is an empirical question, not something which can be deduced from first principles.

Re: How well do cars do in crash tests they're not optimized for?

#238

Post by AgloeDreams »

JoeAltmaier wrote: post #17
laegooose wrote: post #5

The whole car safety topic is very confusing. Car accidents is top1-top2 death reason in US for people in 20-40 age group [1]. Probably less in Europe but still one of the leading ones. I was thinking about how I can make myself safer. Which car brand/model is better? Which seat is better for passenger? How much riskier it is to drive during the night? In the rain? How dangerous is it to overtake on road with 1 lane…

Drive the largest vehicle you can. When in a collision the momentum is converted to crushing force, you want to be in the less-crushable vehicle. Hey this may be an unpopular choice, but it is the one with the biggest safety impact! And that was the question.

This has had little to no real evidence in specifics to SUVs. Plus it increases the risk on others, which is something one should have to realize.

Pluuus, Larger vehicles suffer from worse handling, worse braking distances and higher accident rates. It's all just dumb.

Re: How well do cars do in crash tests they're not optimized for?

#239

Post by AgloeDreams »

frosted-flakes wrote: post #74
dangus wrote: post #21

Earlier quoted context omitted.

On the other hand, all car makes have become much more reliable than they were in the past. Mostly, what you're looking out for is cost of parts and difficulty of labor. For example, a lot of Audi/Volkswagen products suffer from simple repairs being made more complicated by the need to pull things apart for the mechanic to reach them.

In some cases, absolutely. Having to completely disassemble the door to repair a failing lock module is seriously annoying, as is making it impossible to remove the engine mount while the engine is in the car (seriously complicates timing belt changes on VW mk4 cars, because the belt loops around the engine mount). But on the GTI (2009 in my case), they did something rather ingenious: instead of welding the outer doo…

Speaking of timing.. .you got that Timing chain Tensioner replaced right? Mine blew on my 2009 Eos and lunched the motor.

Re: How well do cars do in crash tests they're not optimized for?

#240

Post by Nasrudith »

alistairSH wrote: post #200
henryfjordan wrote: post #85

Earlier quoted context omitted.

VW actively detected if the car was on a treadmill testing setup and electronically changed the engine parameters to make it run cleaner. The water heater was designed with the test in mind but functions the same regardless. VW was clearly cheating whereas the water heater is taking advantage of known deficiencies in the test (is that cheating?).

I'm not sure that's an accurate description of VW's cheat. VW knew the parameters of the test (stationary car, no steering input, prescribed throttle inputs, etc). And they configured the car to pass the test. Water-heater engineer knew the parameters of the test (number and location of probes). And he configure the water-heater to pass the test. Same-same. In both cases, an engineering team willfully committed fraud…

One added difference is that the water heater. The intent may be deceptive but they provided what was asked for and what they claimed. It is almost malicious compliance. Dickish gaming and probably worth suing over but not sure if it is criminal fraud per se.

It is like the joke about Soviet factory metrics for some item like nails. They set the quota on numbers and got useless ones better described as needles. They wised up a bit and set the quota by weight next month and got one useless massive nail instead. It isn't even too far from the truth given actual management involved things like a train line circularly shipping coal between depots instead of retrieving from source or distributing to end users to boost their "metric tons transported kilometers" metric.

VW meanwhile had a covert illegal configuration while claiming mileage and lack of maintenancd urea. The claims are outright false - that it provides all three benefits instead of two of three.

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