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This past weekend was a pretty bad one in the SFO bay area, 9 people killed in 7 different accidents.

One of the accidents that resulted in the death of a mother and daughter was between a Chevy Blazer and a Chevy Cavalier. Both the fatalaties occured in the Blazer when it hit the Cavalier head-on and flipped over on hwy 1 near SFO. I think the speed limit there is 45mph.

There were 2 occupants in the Cavalier, it was reported that one person suffered a scratch to his/her hand but both were otherwise ok. The car was a mess so they really had an incredible escape.

If you were going to pick a car to tangle with a Blazer, a Cavalier would not be on the list at all. However, it just makes you think how unsafe these type of vehicles are and how the general perception of their safety is completely the opposite. :tsk:

I know there may be various other factors involved here but this is not an isolated incident. There are numerous instances of suv's flipping over like this. I dare say that if they were driving a sedan, they would be alive today.
 

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Grumpy and Cynical
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I believe that SUVs are classified as "trucks" and therefore, DO NOT comply to the same safety standards as cars. Funny how most people mistakenly think SUVs are somehow safer than cars. Yes, I know that the X5, M-Class, and the MDX are exceptionally safe vehicles.

Ed
 

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Ed, I will concede that SUV's have a higher roll over factor, and that sedans are 4 times less likely to roll over compared to SUV's but I still stand by my statement that giving Mass is better than receiving Mass. (I might add, we did not even consider safety when buying our SUV, we considered the 4WD and high clearance properties that we needed for our Montana property at 7,000 feet altitude!)

http://www.suv.org/safety.html

Of the 5,259 fatalities caused when light trucks (SUV's) struck cars in 1996, 81% of the fatally-injured were occupants of the car. In multiple-vehicle crashes, the occupants of the car are four time more likely to be killed than the occupants of the SUV"
 

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Simple physics solve the mystery.
the reason why you are more likely to die in a sedan, does not have to do with a 60mph crash test or anything, it has to do with the mass of the vehicle you collide with.

a 3500 pound sedan, that hits a 3500 pound sedan perfectly headon at 60 will both have the same 60 - 0 mph time, and cause about the same damage to eachother. ie. hitting a brick wall. :banghead:

a 3500 sedan vs 7000 suv the suv will have a longer 60 - 0 mph time, while the sedan will have a small 60- 0 forward momentum, but from 0 - x back to 0 due to the force of the mass hitting it and actually moving it backwards...


all that is theory stuff, actual accidents are all different, but the fact that the suv is safer has nothing to do with design, its all about mass. but the things are top heavy as well, which leads to the roll overs.

the truth is, a sedan can be the safest thing in the world but when suvs with double their mass hit them, it changes everything... look at a saftey rating of the #1 safe car vs a fully loaded logging truck, how many fatalities involved for the semis... very few but very high for sedan occupants. it is all related to the mass of the vehicle more mass, more safe less mass, less safe

bottom line... suvs are more dangerous to others, yet more safe for the occupants, due to mass advantage, even if the roll factor is weighed in
 

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Actually, the real threat are the DRIVERS, not the SUV's, Cars, or Logging Trucks.

Guns don't kill people....

SUV's don't kill people....

Stupid people kill innocent people.
 

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Ripsnort said:
Yep, kinda like what I said in an earlier thread...anyway, the REAL threat to all of us are the Semi-trucks!
Er... I usually feel safer driving around a semi than I do an SUV. At least the semi drivers get special training to handle those monstrous things before they can get out on the road.
 

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rootkid said:


Er... I usually feel safer driving around a semi than I do an SUV. At least the semi drivers get special training to handle those monstrous things before they can get out on the road.
Unfortunately, their training is often offset by the fact that they are often over-working and drive long distances under chemical augmentation.

Ed
 

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Ed328Ci said:


Unfortunately, their training is often offset by the fact that they are often over-working and drive long distances under chemical augmentation.

Ed
But what about all those sleepy SUV drivers tyring to make it to work on time through heavy traffic while sipping their coffee? :)
 

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i see to many big rig head ons where i live to think that big rig drivers are safe, they always go over 55 (thier speed limit), they always drive longer than they should per day etc.. id rather take on a suv anyday
 

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There are other factors involved than pure mass to mass.

The pure physics answer given assumes that the masses impact exactly together, like two billiard balls. A higher SUV doesn't hit a lower sedan with maximum energy transfer.

Also due to the difference in crash standards (as mentioned) between cars and trucks, cars have are designed with a controlled crush. First seen on BMW and Volve AFAIK. This means that while hitting a much heavier vehicle is like hitting a brick wall, the controlled crush reduces the G forces in the car substantially. Look at the change at Indy to the outer walls to reduce crash loads.

And then the lack of stability of SUVs means they tend to roll, and in most accidents where SUVs roll, any occupant not wearing a seatbelt is killed.

Overal, the idea that SUVs are safer than cars is comparing apples to oranges. Each have their advantages, each has their disadvantages. Me, I prefer to use the superior performance of my BMW to not be there when the accident occurs. :)
 

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Pinecone said:
Overal, the idea that SUVs are safer than cars is comparing apples to oranges. Each have their advantages, each has their disadvantages. Me, I prefer to use the superior performance of my BMW to not be there when the accident occurs. :)
About 8 or 9 years ago, I was on a freeway in LA. It was normal traffic with the #1 lane moving along bumper to bumper at about 75-80 and a little slower with each lane change to the right. I was in the #1 behind a Camry and, for some reason, no one was too close directly behind me. Up ahead a little bit a bobtail started to skid to the left from the #4 lane and almost instantly, everything up ahead disappeared in tire smoke. I was braking at the verge of lockup in my (shhhhh.....) 92 Civic Si. When the smoke cleared, literally, the Camry had hit the cab, which was now pointed the wrong way, I had come to a stop about 18 inches behind the Camry. And another 4 cars and pickups were caught up in it as well. The other car in my stable at the time was a 91 Taurus SHO. If I had been driving that one at the same unsafe following distance, I would have been into the rear of the Camry. While I had the Civic, there were a couple other times where I was able to swerve around things when I would have run into something with a larger vehicle.

I have an uncle with about 3.75 million miles under his belt. the one crash that he's been in while driving, he was stopped at a stop sign (or light, I can't remember) in a Ford Fiesta :banghead: and was slammed by an out of control dump truck. Not only did my uncle emerge relatively unscathed, but that the car was fixable.

Anecdotes don't count for shit, though. I don't see any wisdom in buying a vehicle with worst case scenario thoughts guiding the purchase. It's very unlikely that the worst case will happen. It's much more prudent to look at what's likely to happen. If the vehicle comes into contact with something, it will probably be at a relativley slow speed and there won't be much damage, and more importantly, no serious injuries will be suffered regardless of what you're in and what the other thing is.

When you (the generic "you") buy/drive an SUV, you do block my and everyone else's visibility through (same for you f*ckers with tinted windows) and around you, making the roads more dangerous for all the rest of us. You use up more than your fair share of the world's petroleum reserves and you don't use the vehicle for what it was designed for. If you do actually go off road, haul crap, or tow shit, then that's fine. Only a very, very few are doing 12,000-15,000 miles a year of that driving though.
 

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pinecone your very wrong and heres wwhy....

even with reduced Gs and crush velocity etc... the higher the mass the worse it will be

you could attach 30 hr racing springs to the front of your car , the suv with more mass will still have a greater stopping effect, regardless of anything
 

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dredmo said:
pinecone your very wrong and heres wwhy....

even with reduced Gs and crush velocity etc... the higher the mass the worse it will be

you could attach 30 hr racing springs to the front of your car , the suv with more mass will still have a greater stopping effect, regardless of anything
Not necessarily. If two same cars hit head on, one with higher mass you would be correct. But vehicle dynamics don't work that way. As long as the CGs are at significantly different heights, the energy transfer equation gets VERY complicated. Also you have to factor in what hits what? As most car to SUV collisions are not bumper to bumper. This will effect whether the collision is an elastic or non-elastic trasnfer of energy.

Add to that the reduced G from the controlled crush (not the same thing as mounting springs on the front), and the very high likelihood of SUV roll over, and it comes out that you cannot say that overall SUVs are safer. Nor can you say categorically say they are less safe either.

It is not an apples to apples comparison. Too many other variables to call.

But you can always say, if you can avoid the accident, you are much better off than in ANY accident.

BTW my background is over 18 years as a safety and health professional. My current job includes motor vehicle safety worldwide.
 
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