safety behind the wheel - bigger isn't necessarily better
 

The prevailing wisdom on this board appears to be that the bigger my car is, the safer I will be. Specifically, this seems to come up whenever someone mentions the Smart car.

Here's one interesting graph from a recent article in American Scientist. It shows risk to drivers and drivers of other vehicles, and the data comes from IHS accident statistics. Note e.g the relative safety of the BMW 3-series, Nissan Altima and Buick Century. Another interesting trio is the Durango, the Explorer and the Blazer.

http://www.americanscientist.org/Lib...03WenzelF4.jpg

Myself? I'll keep my European mid-size with more airbags than cupholders. :)

/ Johan

ps. The article goes into depth about how the results were produced and what conclusions can be made. Link to the source:

http://www.americanscientist.org/issues/feature/safer-vehicles-for-people-and-the-planet/1

Look at the Ford E series. That is wacked out 20-something delivery drivers.. Always good to steer clear..

Risk to drivers and risk to others - all American made..:(

People seem to like to have the potential ability to kill others with their car/SUV.

Makes them feel all powerful or something.

Top-selling cars? They're trucks
http://www.bankrate.com/brm/news/auto/car-guide-2007/20070801_top_selling_cars_a1.asp

wow, that is really surprising.

I'm baffled by how the North American compact cars (Escort, sunfire, cavalier, neon) fared so poorly... maybe rental cars would throw these numbers off?
http://forums.pelicanparts.com/uploa...1213720806.jpg

My first impression is that Eurpoean safety standards must be higher. This is based on the tighter distribution of European vehicles tending toward the lower left and the large number of domestic vehicles that are scattered around the outside of them.

well it looks like it confirms everyones bias

big cars/truck will cause the car they are hitting more damage.
mass and speed make a big difference, also where the point of impact

explorer's suck anyway you put it. blazer doesnt say if it is the smaller or full size version.
durango is probably the bigger version.

they probably got hit by all those big american SUV's

That graph provokes a lot of reactions - the article goes through some of the possible explanations as to why certain cars may be in different areas. What I find interesting is that similar cars, that are likely used in the same fashion and driven by the same type of drivers perform very differently in actual accidents.

• You're 50% more likely to die behind the wheel of a Corolla or Civic than a Jetta.
• You're twice as likely to die behind the wheel of a Grand Cherokee than a Lexus Rx300.

That's not intuitive, but it appears to be what the data is saying.

/ J

Now if they would just make a Hybrid 4WD Odyssey.

well there must be some genetic programming here...americans always equate bigger as better and safer. It is funny that people think a Smart is not safe because it is small

you get in your Smartcar, I will get in my buddy's 1/2 ton Chevy work truck, we crash them into each other and see who walks away.

If you are in 550 kilo telephone booth on wheels, and I hit you in a 2000 kilo body on frame truck, you are going to walk with a much worse limp than I, physics is a funny thing, and can be a bit of a bearcat. Ever see video of a train hitting something?

This is poorly presented info as it insinuates that an equal number of vehicles in an accident represents the total cross section sampled of each vehicle.

"Because we used actual crash statistics, the values we calculated reflect the risk of involvement in a crash and the speed at which it occurs, which hinge primarily on environmental factors and the behavior of the driver, as well as the risk of fatality once a serious crash has taken place, which depends on belt use, vehicle design and driver frailty. As such, our use of the word "risk" here is just shorthand for "risk as a car or truck is really driven."

So that's really sort of a stretch to graph this on a simple X-Y then isn't it.

Bigger=more mass=safer to the occupant and that's exactly why the Army doesn't make tanks out of mail jeeps.

obviously it depends on the circumstances of any accident...My brother has seen people die in what seems to be minor accidents...very low speed stuff..and yet has seen people walk away from huge wrecks....but he always says that suv's/trucks kill more people(both inside and out ) than small cars except when they hit trees.
He says it is the luck of the draw more than anything

That may be true in a controlled experiment, but in real-life driving I bet the 1/2 ton is far more likely to be in an accident than a Smart car.

Up here where I live, people are convinced they need a pickup or SUV to drive in the snow. Funny thing is when it's snowing, they are the first vehicles scattered along the median, shoulder and in the bushes... pointing backwards, on their sides... stunned drivers crying into their cellphones.

Pickups are even worse. Every now and then I borrow my FIL's pickup for some fiasco or another. That thing is terrible in the snow or rain.

I read a good summary somewhere a while ago:
SUVs are safer if you are going to be in a crash, but crappy if you don't want to be in a crash in the first place

Try this:
One guy gets in his Smart Car and have another get in the 1/2 ton pick-up. Both accelerate up to 60mph then have a semi truck pull out in front of them 120 ft away. Lets see which one gets out of that better assuming they both hit the brakes at the same time.

I just can't believe that there are people who would answer "B" to the following question:

2 cars get into a collision. Which car would you rather be in?

A. The Smart car
B. The 6,000 lb. car

Yes, without knowing any other facts, you could be worse off in the 6,000 lb car, depending on the circumstances. But to say that the chances of serious death or injury, in an accident between 2 vehicles where one outweighs the other by 2-3 times, are equal, or it's just "the luck of the draw," doesn't really work.

OK, I can play this game: 40 mph into an offset deformable barrier - European test procedures. I couldn't find any test results for large PUs, but here are a few examples. The 2007 Smart scored better than a 2005 Jeep Grand Cherokee, but worse than 2003 Saab 9-3.

1. 2007 Smart for two crash:
Front impact
The passenger cell remained stable during the impact. Structures in the dashboard presented a risk of injury to the knees and femurs of the driver and passenger.

Side impact
The dummy's head contacted the rubber window trim on the cant rail, leading to a high deceleration. However, the data recorded by the dummy suggested an adequate level of head protection. A side impact airbag to protect the chest and the head is available as an option but was not fitted to the test vehicle.
source:
http://www.euroncap.com/tests/smart_fortwo_2007/303.aspx

2. 2005 Jeep Grand Cherokee:

Front impact
Structures in the dashboard represented a potential hazard to the knees and femurs of the driver and passenger. Protection of the driver's chest was weak.

Side impact
Although the car was eligible, Daimler-Chrysler did not choose to sponsor a pole test.

source:
http://www.euroncap.com/tests/jeep_grand_cherokee_2005/239.aspx

3. 2003 Saab 9-3

Front impact
The knee impact area is particularly well planned, having a knee bolster that is designed to collapse when struck hard. But testers found that the steering column could transmit impact forces to the driver’s knees. The footwell was not deformed by the impact, posing few hazards to the driver’s feet and ankles. The front belts were fitted with load limiters and reel mounted pre-tensioners. Even so, the driver suffered a high-ish chest loading. The centre rear seat belt was of a three-point type, which provides much better protection than that of a lap-only belt.

Side impact
No points were lost for its side impact performance, including the pole test. The curtain airbag protected all occupants on the struck side. This deploys in glancing frontal impacts where occupants may be be partly ejected as the car rotates during impact.

source:
http://www.euroncap.com/tests/saab_9_3_2002/131.aspx

I think that's because pickups don't have to comply with the same safety standards as passenger vehicles. Please correct me if I am wrong on that, but that should give you an indication of how they might perform.

Do you think that if a manufacturer doesn't have to spend the money to meet a safety regulation that they'd go ahead and spend it out of the goodness of their hearts?

As a point of reference here are some of the same test for pickups trucks.

A 2008 Isuzu Rodeo/D-Max

Front impact
The passenger compartment became unstable in the frontal impact and the D-MAX did not achieve the minimum number of points in this test to get a three star rating, even though it scored enough points overall. Protection of the driver's head was rated as weak. The final star is struck through because dummy readings in the neck and chest indicated an unacceptably high risk of life-threatening injury. Structures in the dashboard presented a risk of injury to the knees and femurs of both the driver and passenger. Protection of the driver's lower legs was jeopardised by excessive upward movement of the brake pedal. Protection of the driver's feet was poor, owing to a ruptured footwell and pedal movement.

Side impact
A head-protecting airbag is not available on the D-MAX so a pole test was not performed.


http://www.euroncap.com/tests/isuzu_dmax_rodeo/316.aspx

A 2008 Nissan Navara - I've even put in the modified version which did well compared to the previous one.

Front impact
Nissan have modified the Navara to address some of the areas that caused greatest concern when the car was originally tested. The software that controls airbag firing has been revised and, in this test, the airbags deployed as intended. As a result, protection of the head and neck was good for both driver and passenger. However, the passenger compartment was again unstable which, combined with the chest compression measured by the dummy, led to protection of the driver's chest being rated as weak. Structures in the dashboard presented a risk of injury to the knees and femurs of both the driver and passenger. There was extensive deformation of the driver's footwell and the car was penalised because the lower chassis rail punched a hole in the toeboard. Dummy readings indicated weak protection of the driver 's lower legs and rearward movement of the pedals led to protection of the feet and ankles being rated as poor. Nissan have instigated a service campaign to upgrade D40 Navaras (from VSKCVND40U0016577) with the revised airbag software. Euro NCAP strongly encourages owners to have their vehicles upgraded if invited to do so by Nissan.

Side impact
The Navara scored maximum points in the side impact test. A head-protecting airbag is not standard equipment so a pole test was not performed

http://www.euroncap.com/tests/nissan_navara_2008_2/319.aspx

These did well in the side impact test but I wonder if that might be because the occupant is sitting higher than the impact device?

I understand why there may not be safety ratings for larger pick-up trucks. I'm not sure how the Euro NCAP decides what vehicles to test, but I don't think it's based on safety regulations, maybe by market size?

Here's a picture of what happened to a 2002 Mini Cooper and a 2002 F150 after hitting the same type of offset barrier:

http://www.bridger.us/pictures/mini_vs_f150.jpg
source: http://bridger.us/2002/12/16/CrashTestingMINICooperVsFordF150/

I think Ford has improved the F150 since.

/ J

M-1 Abrams are not subject to the same safety standards either. You think that gives you an indication of how they'd perform in a crash?

Nope.