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The Physics Behind Car Crashes 732

Posted by samzenpus from the drive-a-tank dept.
Guinnessy writes "Physics Today has an article on Vehicle Design and the Physics of Traffic Safety. The article analyzes in detail typical crashes experienced between cars, and cars with SUVs'. According to Marc Ross, Deena Patel, and Tom Wenzel, "The evidence is compelling that body-on-frame light trucks cannot safely coexist with passenger cars under existing conditions. That problem is critical because so many light trucks are used nowadays as car substitutes." They suggest some ways in which both cars and SUVs' can be redesigned to improve safety. Meanwhile Detriot News reports on a Pediatrics journal study says that claims that children are no safer in SUVs than cars because of the rollover risks."
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The Physics Behind Car Crashes More

The Physics Behind Car Crashes

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  • I reckon.. (Score:5, Funny)

    by DeathByDuke ( 823199 ) on Thursday January 05, 2006 @06:45AM (#14399031)
    ..that one of their findings was that cars dont explode upon slightly touching each other!

  • weight& speed are the big issue here (Score:3, Insightful)

    by jacquesm ( 154384 ) <j AT ww DOT com> on Thursday January 05, 2006 @06:48AM (#14399041) Homepage
    you don't have to be Einstein to remember that e=mv^2, and that if you want to reduce the damage to you, yours and the occupants of other vehicles you keep your speed down and your vehicle weight down.


    Driving fast in an SUV loaded with kids is about as unresponsible as it gets, I see it quite often though...


    • Huh? e=mc^2, where c is the speed of light, a constant. I do believe you are talking about the equation for momentum, which is mv(mass times velocity) ie increasing either mass or velocity raises you momentum linearly.....

      • You're both wrong. or right. (Score:5, Informative)

        by tabrisnet ( 722816 ) on Thursday January 05, 2006 @07:04AM (#14399075)
        KE = (m/2)*v^2

        or the more common form: KE = 1/2mv^2

        This incidentally does make it in the same class as E=m*c^2 (due to magnitude/exponentiation) but that's more or less irrelevant.
      • I learned the old school stuff like F=ma.

        Also, from the GP that says "keep your speed down and your vehicle weight down".

        I would rather be in a fully loaded 18 wheeler going 100 MPH than in a Honda Prelude sitting still.

        Now with the SUVs not being any safer for kids, the same is true with antilock breaks. They are both better at reducing injuries in not so hazardous situations, but both are more likely to kill you in serious situations.

        • They are both better at reducing injuries in not so hazardous situations, but both are more likely to kill you in serious situations.


          It is true for the people in your car probably having less injuries when yours has the largest Mass but the question remains of what is the impact when an SUV hits another SUV? Are you still as safe as hitting a car?

          • Re:weight& speed are the big issue here (Score:5, Informative)

            by i_should_be_working ( 720372 ) on Thursday January 05, 2006 @07:30AM (#14399124)
            Whoever is in the car that undergoes the largest acceleration is worse off. Since mass is by definition the resistance to acceleration, the ones in the larger car win. If two equal mass cars collide they both undergo the same acceleration. Ignoring car vs SUV strength, if two cars have a head-on collision at 30mph, the people inside are just as well off (or just as injured) as if it were two SUVs.
            • So as soon as SUVs have taken over, people will buy Sports Utility Tanks to be safe again.

        • Re:weight& speed are the big issue here (Score:5, Insightful)

          by owen_b2 ( 660177 ) on Thursday January 05, 2006 @07:47AM (#14399166)
          the same is true with antilock breaks

          Since when? Are you alluding to the misconception that a good driver can stop faster without ABS than an average driver with? With modern ABS this just isnt true anymore, even if you're a rally driver.

          And ABS systems let an average driver steer their car in a heavy-braking-potential-skid situation, where the non-abs car will be skidding in an uncontrolled straight line. How many drivers are taught cadence braking these days?

        • Now with the SUVs not being any safer for kids, the same is true with antilock breaks. They are both better at reducing injuries in not so hazardous situations, but both are more likely to kill you in serious situations.

          I might have bought into this a decade ago, when people were still unfamiliar with how ABS worked. Early on, people would slam on the brakes, get the feedback, and pull back because it felt wrong. They were then dealing with two issues -- whatever they were trying to avoid, and an unexpect

    • Re:weight& speed are the big issue here (Score:5, Informative)

      by i_should_be_working ( 720372 ) on Thursday January 05, 2006 @07:26AM (#14399114)
      As others have pointed out, this has nothing to do with E=mc^2.

      In addition, in a large vehicle the conservation of momentum is on your side. It's not the crash that kills you it's the sudden acceleration (your body going from 30 to 0 mph in a second). But if your vehicle doesn't change velocity much (because of its large mass, mass==resistance to acceleration) then you're fine. The other guy dies. That's why there don't have to be seat belts on buses (though it would still be a good idea). If a bus crashes into something, it's probably not going to stop very fast.

      Large mass is not why TFA says SUV's are dangerous, it's because they tip over.

      • Re:weight& speed are the big issue here (Score:5, Funny)

        by AndroidCat ( 229562 ) on Thursday January 05, 2006 @09:01AM (#14399379) Homepage
        But strangely, the bus will rapidly gain mass after an accident, from all the people who said they were on the bus [expertlaw.com] and want to file an injury claim. Even stranger, this mass gain happens even when the accident is simulated.

      • In addition, in a large vehicle the conservation of momentum is on your side. It's not the crash that kills you it's the sudden acceleration (your body going from 30 to 0 mph in a second).

        The mass of the vehicles involved is an interesting and significant data point but it's not the whole story. The way the shape of the vehicle changes during a collision is extremely important. The force with which you're whipped around against your various restraints and airbags is important, but none of that matters if th

      • No.. as the article says, deaccleration of the vehicle itself has very little to do with the safety of the occupants. Even in the most forceful collisions the car will deaccelerate at less than 100G's. Human's regularily survive deaccelerations up to 150-200Gs when the force is spread out.

        The problem is peak loads as the occupant collides with the interior of the car. The design goal is to keep the passenger in his seat, and the passenger compartment largely intact. A stiffer vehicle hitting a less stif
    • The special relativity formulation is E=gamma*m*c^2, where gamma = 1/sqrt(1-v^2/c^2), v is velocity of the object, and c is the speed of light.

    • Re:weight& speed are the big issue here (Score:4, Insightful)

      by Vellmont ( 569020 ) on Thursday January 05, 2006 @07:45AM (#14399158) Homepage
      And you don't have to be an Einstein to know that kinetic energy isn't what kills people, it's the sudden stop that does. If I jump out of an airplane and atain terminal velocity, but deploy a parashoot I'm a lot safer than jumping out of a tree. The point is that if all that extra weight is put into engineering stronger cars that absorb the impact and slow you down more gradually then you're going to be more likely to survive a crash.

      That's not to say that SUVs are safer than normal cars. The rollover risks aren't trivial. Personally I think SUVs should be banned, or at least put into some special category of business only use because of the safety risks they put on other cars. The SUV craze is literally killing more people and making driving for everyone else less safe, and this article proves it.

      • Re:weight& speed are the big issue here (Score:4, Informative)

        by boingo82 ( 932244 ) on Thursday January 05, 2006 @12:24PM (#14400871) Homepage
        The point is that if all that extra weight is put into engineering stronger cars that absorb the impact and slow you down more gradually..

        That's not necessarily what's being done.

        Many of the largest SUVs (Suburban for example) are on a longer redesign schedule than your standard passenger vehicle. Going 8 years between a full redesign means you're still getting crash technology that's nearly a decade old.

        Making matters even better, is that the largest of SUVs, by virtue of their GVWR (a number that's made up by the manufacturer) are not required to meet several bare-minimum government safety standards.
        The current Suburban, with a GVWR of 7000-8600 lbs, is exempt from government roof crush tests. (PDF) [nhtsa.com](As is any vehicle with a GVWR over 6000 lbs.) Unfortunately, passing them wouldn't mean much either - as the minimum only requires a vehicle with windshield intact to withstand 1.5 times its weight pressed down on the roof.
        In a rollover, the windshield is usually gone by the end of the crash, and forces can easily exceed 1.5 times vehicle weight.
        The current standard has been in place - and unchanged - since 1971, and many SUVs aren't required to pass even that lax standard. Many are also exempt from other minimum standards, like Steering Wheel Rear Displacement (only applies to cars with GVWR 4,000 lbs and less), and basic braking standards (applies to vehicles with a GVWR of 7,716 lbs and less).

        Detroit, of course, insists the existing rules are adequate [detnews.com] - the rules that often don't apply to their vehicles.

        Even better, it's been shown that they misrepresented data from their own tests to the NHTSA. [consumeraffairs.com]

        Obviously, we all have to be more proactive in researching the safety of the vehicles we purchase - and not just go out and buy something "big" that "feels safe". Often, we may be safer in that type of vehicle, but only in multi-vehicle-non-rollover crashes - and to what expense? Raising the weight of your vehicle may reduce the risk to your family by 1/3 in some wrecks, but you've increased it threefold to the other car.

  • Builders wagon (Score:2, Funny)

    by Anonymous Coward

    funny how driving a builders wagon became fashionable, perhaps milk floats are next, or even a dustcart !, we can only live in hope

  • Physics of car crashes aren't intuitive. (Score:5, Interesting)

    by danamania ( 540950 ) on Thursday January 05, 2006 @06:51AM (#14399046)
    I'm reminded of an accident I almost saw several years ago. It was at an intersection where the east/west road had right of way, and the north/south road had a Stop sign. I was in a friend's shop at the time, and we heard a V8 accelerating hard, then a sudden very loud *thud*.

    Running outside, we saw from the accident that a 1970s V8 Statesman with a P Plate (here, drivers get P plates to tack on their car for the first few years they're driving on their own) had obviously gone through the stop sign and hit the driver's side of a Prelude driven by an elderly driver. The young guy in the statesman was taken off to hospital, but a rescue team was needed to pull the driver out of the Prelude. Later that night the news had a piece about the accident, saying that the p-plater had caused an accident that killed the elderly guy. Even witnesses at the scene said they heard the V8 go through the intersection far too fast, and hit the prelude.

    Then the next night, video shot from inside a building nearby showed the accident - the P-plater had actually stopped at a pedestrian crossing, let the people walk across, then accelerated quickly & noisily... but he was actually moving along the east/west road with right of way. It was the driver in the prelude that had gone through the stop sign at high speed, and the young fellow was just in the wrong place at the wrong time, and hit the driver's side of the prelude hard - both cars went spinning around in an impossible looking way, ending up in a position that looked for all the world like the young fellow had gone through the stop sign, even though in this case the only thing he'd done 'wrong' was make a big ol' noise in first gear. My "obvious" guess at who was in the wrong was completely off.

    There's a massive amount of energy in a car collision, more than most people would expect given how much we take moving a tonne or two of steel from one place to another daily.
    • There's a massive amount of energy in a car collision, more than most people would expect given how much we take moving a tonne or two of steel from one place to another daily.


      well the best way to drive home just how much energy it takes to move a car is mandantary push starts(and pushing it downhill is cheating).
    • So basically what you've got here, is two incompetants that cannot drive properly. One couldn't bring the car into motion competantly, and the other was unable to obey one of the most basic rules of the road.

      I see these guys that lurch their cars into motion and heave them around corners at unreasonable speeds. I've also seen feckless individuals with complete disregard for stop signs, right of way and even indicators. Both irritate me no end. Quite frankly it secretly delights me when I see these stereotyp
      • I'm learning to drive, and people who treat indicators as an optional extra are nothing more than life threatening. It's difficult enough for me to try keep tabs on everything I should be doing, what other people are doing, and what the road markings tell me to do without some asshole merging lanes without indicating.

        As for the mostly males involved in crashes, it's the same statistical nonsense as mostly red cars are involved in crashes. It's simply because there are more males on the road to be driving da
        • Harg- I remember turning 25 and having my auto ins. drop a bunch. There was a recent study that showed the majority of people who drive while on the cell phone are women, so I am sure someday this will be reflected in the actuarial tables.
          On a somewhat related note, i never understood how gay people who want to get married, but can't here in the US (most states) haven't sued the insurance companies. Married men pay a lower rate than unmarried men, but gays don't have this opportunity. Seems like a great wa

        • Re:Physics of car crashes aren't intuitive. (Score:4, Insightful)

          by Zog The Undeniable ( 632031 ) on Thursday January 05, 2006 @09:26AM (#14399500)
          The insurance companies aren't screwing you (or at least, no more than anyone else). They use actuarial tables which show the average younger driver, or any driver with no clean driving history, is several times more likely to have an accident.

          Now I was never a particularly aggressive driver (and the only accident I ever caused was when I reversed into a concrete pillar) but I can safely say that in 19 years of driving I leave a lot more space in front and anticipate other drivers' bad behaviour better than I used to. Hell, when I was 25 in a little 988cc car I used to drive a section of country lane in about half the time that I would risk it now - in a car with 2.5x the power. It's all about testosterone and perceived invincibility.

      • I would throttle them, but that would make _me_ the bad guy.

        Ha. That made this pop into my head:

        "Ironic, isn't it Smithers? This anonymous clan of slack-jawed troglodytes has cost me the election. And yet, if I were to have them killed, I would be the one to go to jail. That's democracy for you."

        Mr Burns, of course :-)

    • Re:Physics of car crashes aren't intuitive. (Score:5, Interesting)

      by Gordonjcp ( 186804 ) on Thursday January 05, 2006 @07:44AM (#14399156) Homepage
      I've seen pictures of a crash involving a Renault Megane, and a Hummer H2. The H2 ran through a red light and got cokebottled by the Megane. So - SUV versus small European MPV. Sounds like no contest, right?

      Damn Straight.

      The Megane was very severely damaged, with the driver and front passenger sustaining some injuries, mainly limited to cuts from glass and severe bruising. The passenger hit her head on a bent bit of A-pillar.

      The H2 was *destroyed*. The impact knocked it on its side, and pushed the gearbox and transfer box through the floor and out through the roof. The chassis was split in two from about the middle up to the front crossmember.
      I suppose I don't need to draw any pictures of what this did to the four occupants.
      • I find that hard to believe, but even if it's true, it's hardly representative of most SUV vs. passenger car crashes. It's just not. Perhaps the H2 is just poorly constructed in terms of side-impact protection or something, I can't say since I'm not familiar with it, but imagine that same collision occurring head-on. It barely matters what equipment each car has, because the H2, having much more mass, is going to decelerate much less violently. It's just not going to experience as serious a collision as the smaller car will.

        There are many studies which support this (besides TFA), and I've personally seen (as an EMT) some really hideous SUV/Car collisions, and can tell you: the SUV usually wins. Sometimes there are mitigating factors, like the SUV will roll over and throw out and crush anyone that's not seat-belted, while the car will basically stay in one place, but if you have the choice between being in a Honda Civic and a GMC Suburban with similar safety equipment when they run into each other, you'd be insane not to pick the Suburban. Plus, the increased size of the car makes it likely that you'll get extricated from the vehicle a lot faster (again, assuming no rollover).

        The biggest problem with SUVs, traditionally and still, is that they tend to roll over during hard panic maneuvers, or when hit from the side. Where I used to live, the biggest risk was people driving them too fast for conditions (no, your SUV does not mean you can drive on ice) and laying them over -- generally nonfatal though. But in a straightforward front-end or rear-end collision, there's something to be said for surrounding yourself with several thousand extra pounds of steel. Granted, you get that advantage at the expense of the person in the smaller car, and you have to be more careful taking it around a corner, but it's there nonetheless.

        • Re:Physics of car crashes aren't intuitive. (Score:5, Insightful)

          by the_bard17 ( 626642 ) <theluckyone17@gmail.com> on Thursday January 05, 2006 @08:45AM (#14399327)
          The biggest problem with SUVs, traditionally and still, is that they tend to roll over

          Not from my point of view... their problem is this: the SUV usually wins. From my meager time in life, I've seen plenty of reckless drivers. Not all of them were teenagers... I've seen my share of reckless soccer moms, businessmen, and delivery drivers. Quite a few of these drive heavier vehicles. I suppose it makes them feel safer, being in a heavier vehicle (which they probably are).

          They continue their reckless driving habits, however, now becoming that much more of a threat to the general populace driving smaller cars. They may be more likely to survive, but they're decreasing the chance of survival for everybody else.

          Until everybody "wises up", goes out and buys an heavier vehicle... at which point we're right back at square one, with worse gas mileage.

          • Re:Physics of car crashes aren't intuitive. (Score:4, Interesting)

            by skaffen42 ( 579313 ) on Thursday January 05, 2006 @10:14AM (#14399773)
            Too true... unfortunately it seems that SUV drivers believe the hype that they are invincible. I'm "trail-rated" so I can go anywhere at any speed!

            I saw the result of this last Saturday when there was some freezing rain early in the morning. Driving down Route 80 I counted 14 accidents in the space of about 20 miles. The majority of the vehicles involved were SUVs, and when a car was involved it was usually because an idiot in an SUV had rear-ended them. Worst accident was some large SUV that looked liked it had rolled end-over-end. Couldn't have been more squashed if it had been hit by a train.

            The combination of vehicle weight and perceived driver invincibility seems to make SUVs deathtraps in anything other than perfect driving conditions. Ironic, when you think about it.

          • Re:Physics of car crashes aren't intuitive. (Score:5, Insightful)

            by killjoe ( 766577 ) on Thursday January 05, 2006 @10:28AM (#14399867)
            "Quite a few of these drive heavier vehicles. I suppose it makes them feel safer, being in a heavier vehicle (which they probably are)."

            They probably are safer in their huge SUV. Too bad they are not thinking about the people they will murder though. If they were driving a lighter car which would more effectively crumple and absorb impact the people in the other could maybe survive.

            I guess it re-inforces the stereotype of the SUV driver as the guy who doesn't give a shit about anybody else except themselves. Don't care about the environment, don't care about foreign oil dependency, don't care about the survival of the other guys in the crash.
          • I do not believe people are going to wise up anytime soon, without some impetus. Historically, money has been a good influencing factor on purchasing decisions.

            What I propose is that all vehicles that are not commercially owned (that is a separate issue) be grouped together. No distinction between the fuel consumption and crash standards for cars versus pickups & SUV's. Rate them all on the same scale, provide the same penalties to anyone who violates the accepted standards. If we applied the same s

      • Re:Physics of car crashes aren't intuitive. (Score:5, Informative)

        by arivanov ( 12034 ) on Thursday January 05, 2006 @09:17AM (#14399453) Homepage
        Meganne safety rating is off the scale. The occupant safety level is so good that they are having to redesign the tests because of it. At 35 mph collision of any type (front, side flat, back and side pillar) there is no damage to the occupants. At all. The test result is all green with a possible minor spot of yellow (which corresponds to a bruise). Just look at the EUROncap safety tests http://www.euroncap.com/ [euroncap.com]. Same for every Renault made in the last 3 years.

        At the same time the Hummer is not even on the list. In fact if it was, it would have pulled a 2-2.5 star rating at best. Same as a suicidal box like Fiat Ceicento. I have seen a crashed Hummer so this unscientific opinion is based on seeing what happens when it smashes. If you are driving this POS you have a death wish.

        Essentially even being in a something microscopic by American standards (like Modus http://www.euroncap.com/content/safety_ratings/det ails.php?id1=1&id2=201 [euroncap.com]) is safer then being in a Hummer.

      • Re:Physics of car crashes aren't intuitive. (Score:4, Funny)

        by Karma Farmer ( 595141 ) on Thursday January 05, 2006 @12:37PM (#14401028)
        I suppose I don't need to draw any pictures of what this did to the four occupants.

        This is how we know you're lying -- no H2 has ever had four passengers at the same time.

        Unless you mean the driver and three bags of groceries.

  • European car security (Score:5, Interesting)

    by sucker_muts ( 776572 ) <sucker_pvn@hotmCHICAGOail.com minus city> on Thursday January 05, 2006 @06:52AM (#14399050) Homepage Journal
    The newest european cars nowadays come with an extra protection agains collisions with pedestrians: The hood in front of the car is lifted a few inches after 40 or so milliseconds so the pedestrian gets lifted as well and won't get run over by the car but lands on the softer hood and might hit the car glass.

    The powertrain generally takes up considerable space in the engine compartment, leaving little room between the engine and the bonnet.
    To remedy this, the C6 comes with an active bonnet system as standard that automatically raises the bonnet in the event of pedestrian impact. Thanks to an impact sensor and pyrotechnic mechanism, the bonnet rises 65 mm in 40 milliseconds. A second mechanism maintains the bonnet in its raised position despite the impact and thus absorbs the deformation energy.

    Example from Citroen. [citroen.com]

    • The hood in front of the car is lifted a few inches after 40 or so milliseconds so the pedestrian gets lifted as well and won't get run over by the car but lands on the softer hood and might hit the car glass.

      Wow! That's great! Now instead of plebs getting messily caught in my undercarraige, they'll just hit the bonnet and windshield and bounce right off! I can just turn on the sprinklers and wash the blood right off while I sip on my latte! This is genius!

      The only downside I can think of is that they may b

      • Re:This Is Genius! (Score:3, Informative)

        by 10Ghz ( 453478 )
        The idea is pretty simple. When the bonnet raises, there's more room to absorb the impact-energy. Earlier, the only things absorbing the energy were the metal on the bonnet and engine, and the bones in the pedestrian. With this system, the bonnet can absorb more of the impact-energy, sparing the pedestrian.

        Here [euroncap.com] is the EURO-NCAP test-report for Citroen C6. As it happens, it's the first car to achieve the maximum score for pedestrian safety.
      • so, what you really want is a whacking great big cow-catcher to shove them to one side or the other...

  • Well, that settles it then... (Score:5, Funny)

    by shmlco ( 594907 ) on Thursday January 05, 2006 @06:52AM (#14399051) Homepage
    "The evidence is compelling that body-on-frame light trucks cannot safely coexist with passenger cars..."

    Well, that settles it then. It's obvious we need to outlaw passenger cars. Not only will that remove millions of unsafe cars from the road, it will give a much needed economic boost to the SUV manufacturers.

    Besides, if a car is unsafe around a light body truck, it must be a death trap around a standard truck or a semi-tractor trailer rig...

    • "The evidence is compelling that body-on-frame light trucks cannot safely coexist with passenger cars..."
      Strangely, a body-on-frame light truck has been safely coexisting with a (subcompact) passenger car in my garage for the past two years. Amazingly, they both go out and coexist with all other vehicles on the roadway, ranging from bicycles to 18 wheelers, without incident.

      I find it amusing when the vehicle is blamed rather than the operator.

    • Besides, if a car is unsafe around a light body truck, it must be a death trap around a standard truck or a semi-tractor trailer rig...

      And the trucking industry constantly lobbies for greater weights for their trucks. Which cause lots of wear and tear on the roads if nothing else. But now they can't stop as quickly, and they can't get out of their own way on a hill, resulting in mini traffic jams and high speed differentials, which are a dangerous situation.

  • Canyonero! (Score:3, Funny)

    by Life700MB ( 930032 ) on Thursday January 05, 2006 @07:01AM (#14399068)

    12 yards long, 2 lanes wide,
    65 tons of American Pride!

    Canyonero! Canyonero!

    Top of the line in utility sports,
    Unexplained fires are a matter for the courts!

    Canyonero! Canyonero! (Yah!)

    (Entire lyrics here [saiyine.com])


    --
    Superb hosting [tinyurl.com] 20GB Storage, 1_TB_ bandwidth, ssh, $7.95

  • Chinese SUV (Score:5, Interesting)

    by lovebyte ( 81275 ) * <lovebyte2000@gmail3.1415926.com minus pi> on Thursday January 05, 2006 @07:04AM (#14399076) Homepage
    I don't know for the USA, but a chinese SUV is being imported into Europe and it received a 0 rating for safety [timesonline.co.uk].
    So be careful! If you see one on the road, stay well clear.

    • Re:Chinese SUV (Score:5, Funny)

      by bobdotorg ( 598873 ) on Thursday January 05, 2006 @07:24AM (#14399111)
      Overheard at a cafe in Stockholm:

      Volvo Engineer: But your SUV is so dangerous - it has no crumple zones.

      Chinese Car Salesman: Silly Swede. You Volvo my crumple zone.
    • ""This car seems to belong in the 1990s in terms of engineering,""

      As someone who drives a 1990s car, which replaced a 1980s car which was designed in the 1970s, that doesn't sound too bad to me...

      Of course if it's anything like the asian 4x4 I rented one time when my car was being fixed (asked for a smaller car but that was all they had left when I got there to pick it up), they won't be able to go fast enough to do much damage in a crash without rolling the thing.

    • Re:Chinese SUV (Score:3, Informative)

      by AtomicBomb ( 173897 )
      How bad? Probably as bad as a similar vehicle the 1990s... And, it is probably the sort of vehicle most driver are with if they are in the budget sector. Check the link below for a comparison [bootnetworks.com] between different SUVs + the Landwind. The Volkswagen survive well, the Landwind fails miserably. But, the 2003 Ford Explorer and the Isuzu Rodeo are not much better off. Based on truck design, the protection of a lot of SUV are jsut not up to it. Before laughing out loud, most of us should realise that we are si

  • PDF warnings (Score:2, Informative)

    by simpsone ( 830935 )
    Hows about a warning of some sort about the pdf lurking behind the first link there? Maybe a little something in parentheses would do.
  • can't safely coexist with anything, but I still love mine.

  • People will always buy an auto they feel safe in (Score:5, Interesting)

    by fantomas ( 94850 ) on Thursday January 05, 2006 @07:13AM (#14399091)
    People are always going to consider their own selfish personal safety as a purchasing factor when choosing a road vehicle; for many people this is a very significant issue, and is played upon by advertising for autos.

    We need to focus on methods of ensuring safety that don't threaten other road users: win-win situations rather than soccer moms driving trucks and declaring "I know I will win in a collision" (vaguely remembered quote from a National Geographic article on SUVs). This can only lead to a sort of arms war where we all end up driving 38 tonne truck rigs....I was particularly scared by the picture of the SUV built on what is effectively a couple of forward facing railroad rails - that's going to hurt if you're hit side on in a little compact by one of those.

    The annoying thing is I am sure most of the safety issues can be solved with little cost and by improving social as well as technological aspects of road use, e.g. severely enforcing low speed limits round residential areas. As long as its cool to drive like a bastard people will.

    I always like the story about how there were a lot of fatal accidents in early autos because of the bolt protruding in the middle of early steering wheels, head on crashes meant drivers suffering lots of chest damage; while this was then changed to make life safer, it's been pointed out that if there was a big spike compulsorily welded onto the middle of all steering wheels pointing at drivers then everybody would drive a whole lot more carefully and there would be a lot less accidents.....

    • Re:People will always buy an auto they feel safe i (Score:5, Insightful)

      by dkleinsc ( 563838 ) on Thursday January 05, 2006 @08:34AM (#14399299) Homepage
      The SUV craze is actually the same phenomenon as the crowded theater phenomenon (where someone stands up to get a better view, so soon everyone is standing to see at all, and no one sees any better than when they were sitting). The idea is "If my vehicle is heavier than the other guy's, then in an accident I'll be in better shape than him." End result: Everyone will go out and get a bigger vehicle, because it appears that will make them better off, and as a result no one is safer.

      Of course, the heavier vehicles always create a false sense of security. Trucks and large vehicles are more prone to rollovers, can't stop or swerve easily to avoid trouble, and hit stationary objects with more momentum. But like Homeland Security or MS Windows, it makes you feel safe, so people choose to go with it even if the facts are completely against them.

      Really your best defense while driving is to actually use everything you learned in Driver's Ed, or if you don't remember than find books or classes on safe driving. And if there are any teenagers reading this, remember that Driver's Ed is the one class most likely to determine at some point whether you survive a situation. You know, driving at reasonable speeds (somewhere around the speed limit is usually good), slowing down before you take corners, being aware of the drivers around you, good signalling so other drivers are aware of you, etc.

  • On SUV safety (Score:5, Interesting)

    by Oldsmobile ( 930596 ) on Thursday January 05, 2006 @07:37AM (#14399139) Journal
    Funny thing anout SUV's. They really are a hazard. Not only is the center of gravity higher, but they usually have misdesigned suspension (Ford Exploder, Mitsubishi Montero) that actually encourages rolling over, SUV's have higher bumpers, so cars running into them slide under, killing the occupants in the lower car. SUV's use more gas and cause more pollution. A very big problem is roof crush. SUV roofs are notorious for being frail and crushing in a roll over accident, squishing the people inside.

    I for one don't like the idea of dying by having my spinal column driven into my skull.

    Many of these things of course could be mitigated. There could be a standard lane change test to determine suspension quality, there could be rules on the center of gravity, there could be rules on bumper height (like on regular cars) and there could be rules on pollution, perheps making all SUV's except the kind with frugal modern common rail diesel engines (with particle filters) financially impposible to own/buy.

    But this is not the case. Infact, with GM and to some extent Ford in financial trouble (and with all their profits coming from SUV's) the current US administration wil do nothing about the laws, that infact make SUV's above the law.

    Right now, SUV's are excempt from current fuel efficiency laws (that are not very good in the first place, mind you), they are excempt from bumper laws (making SUV's lousy and expensive to fix in even the smallest parking lot accident) and there are no laws governing roll-overs (only tests).

    With all these problems, I don't see why they even allow these on the road.

    The funny thing is, I really like the idea of sitting up high in my car and being able to see further. That is probably the only reason SUV's are so popular. Looks like they could accomplish that in a macho looking vehicle without these problems.

    Cross-over anyone?

    • Re:On SUV safety (Score:3, Insightful)

      by RosenSama ( 836736 )

      Many of these things of course could be mitigated. There could be a standard lane change test to determine suspension quality, there could be rules on the center of gravity, there could be rules on bumper height (like on regular cars) and there could be rules on pollution, perheps making all SUV's except the kind with frugal modern common rail diesel engines (with particle filters) financially impposible to own/buy.

      The car buying market in the US is pretty democratic. People buy what they want. We do

  • Insurance costs could fix this (Score:2, Interesting)

    by Anonymous Coward
    My insurance company charges more for cars whose occupants are likely to be injured. I would propose the opposite approach. They should charge more for vehicles who are likely to injure the occupants of other vehicles. The driver of the giant pickup truck would be penalized for putting my life at greater risk. That would get a lot of those vehicles off the road. If you need something to boost your ego, you could drive a luxury import; it's actually the safest thing you can drive.
  • I'm happy with my moonbuggy, the safest vehicle out there. http://moonbuggy.msfc.nasa.gov/images/mbmid.gif [nasa.gov]
  • The UK has seen an explosion in the numbers of people driving around in ridiculously proportioned vehicles. America has lived with them for decades so your cities are built around them. The UK is not. Parking spaces are a lot smaller.

    I was waiting outside a supermarket the other week, in a parking slot, and one of these tossers shows up and stops in front of me to let out his passengers before moving into a space. The reason was obvious. His car was too damned big to get the doors open properly when it was
  • 1/ I consider myself to be a safe, knowledgeable and alert driver. Therefore I'd prefer to be the one on top if someone who was less so hit me.

    2/ "Top Gear" in the UK ran a piece about how SUVs run over other cars, thereby causing lots of damage. The pointed out that in most collisions, one car will run over the other anyway, even identical models with different tyre pressures or suspension wear.
    • 5th Gear did a test a while back on 4x4's in near-miss conditions. They took a couple of normal cars, drove them along at motorway speeds and simulated a motorway incident with the front car slamming on it's brakes and the back car having to swerve to avoid it. Nomatter what they did they could only make the car spin, not roll over. They then re-ran the test but this time at only 40mph and with a 4x4 as the second car - it rolled right over as soon as the driver swerved to avoid the stopped car. Certain

  • what is the definition of "safely" ? (Score:5, Insightful)

    by tjic ( 530860 ) on Thursday January 05, 2006 @08:07AM (#14399218) Homepage

    "The evidence is compelling that body-on-frame light trucks cannot safely coexist with passenger cars "


    The author of the study is making the mistake that safety is a boolean, and that things are either safe or unsafe.

    In fact, everything is unsafe, to varying degrees. ("Life", in the words of Warren Zevon, "is gonna killa you").

    The important thing, when contemplating questions of public policy, is to COMPARE one risk to the next, and make sure that we're making reasonable decisions and tradeoffs.

    For example, over the last 10-15 years, a lot of states have dropped the DUI (driving under the influnce) BAC cutoff (blood alcohol content) from 0.1% to 0.08%. Lower is better, right?

    Well, as it turns out, having a BAC in the 0.08 - 0.10% range has the same effect on driving ability as (a) having a cold; (b) getting a poor night's sleep; (c) being over the age of 50.

    If we're going to make a 0.81% BAC illegal (and punish it with major fines), should we not also have the same punishments for driving while having the sniffles, or while being 51?

    The answer is that one behavior gets a penalty because it sounds good, makes politicians look like They're Doing Something(tm) and has moralistic overtones ("get those damn drunks off the road!").

    To say that "light trucks cannot safely coexist with passenger cars " is purest nonsense. We've had light trucks coexisting with passenger cars for 70 years, and the fatality rate drops every single year. Sure, if you could snap your fingers and get every pickup truck, minivan, delivery van, and SUV off the road, things would get incrementally safer for the average driver of a passenger car. ...but how much safer?

    I don't know off the top of my head, but is it a level of safety comparable to every passenger car driver making sure that their tires are fully inflated before each trip? Or more, or less?

    Absolutist boolean statements like "X can not safety coexist with Y" do not answer questions like this. These statements are public-policy-by-press-release and deserve to be condemned.
    • Well, as it turns out, having a BAC in the 0.08 - 0.10% range has the same effect on driving ability as (a) having a cold; (b) getting a poor night's sleep; (c) being over the age of 50.

      If we're going to make a 0.81% BAC illegal (and punish it with major fines), should we not also have the same punishments for driving while having the sniffles, or while being 51?

      Being convicted of a DUI is a crime in most states. In mine, you get 3 years in prison after the third one. Here is an account of such an unfortu

  • Mini vans vs SUV's (Score:5, Interesting)

    by pease1 ( 134187 ) <bbunge@ladyandtr ... m minus language> on Thursday January 05, 2006 @08:46AM (#14399330)
    I've always been struck (pun intended) how the day I grew up and traded my SUV in for a mini-van that is about the same weight and gets about the same miles per gallon, I suddenly became more policitically correct, safer and less of a risk to everyone one else on the road.

    And they say there is no free lunch.

    Funny thing is, other then the "coolness factor," I do everything I used to do in the SUV with the van, and the van is actually better at it since it carries more. This likely includes more off road travel then most SUV's ever see.

    • You could also do the same by buying a pickup truck. I remember a Biology class (taught by an Ecology professor) I took in college where I called out my professor for not mentioning pickups when he asked who in the classes owned SUVs and tried to convince them that they shouldn't.

      What's funny is that he started asking what the students needed their SUVs for and then quickly stopped when three of the first four students he asked actually needed their SUV for summer jobs (towing a large landscaping trailer,

    • Re:Mini vans vs SUV's (Score:3, Informative)

      by stienman ( 51024 )
      The main difference is the body style and bumper height. The bumpers for minivans are close to or at the height required for passenger vehicles. This results in crashes that are much different than an SUV crash. Further, the center of gravity is lower on a minivan than an SUV, though not a lot.

      Of course, one can always mine the data [dot.gov] oneself. The query function is fairly easy to use.

      -Adam

  • Obligatory Simpsons quote (Score:3, Funny)

    by ning ( 763275 ) on Thursday January 05, 2006 @09:04AM (#14399386) Homepage
    Can you name the truck with four wheel drive,
    smells like a steak and seats thirty-five..

    Canyonero! Canyonero!

    Well, it goes real slow with the hammer down,
    It's the country-fried truck endorsed by a clown!

    Canyonero! (Yah!) Canyonero!
    [Krusty:] Hey Hey

    The Federal Highway comission has ruled the
    Canyonero unsafe for highway or city driving.

    Canyonero!

    12 yards long, 2 lanes wide,
    65 tons of American Pride!

    Canyonero! Canyonero!

    Top of the line in utility sports,
    Unexplained fires are a matter for the courts!

    Canyonero! Canyonero! (Yah!)

    She blinds everybody with her super high beams,
    She's a squirrel crushing, deer smacking, driving machine!

    Canyonero!-oh woah, Canyonero!

    Support your local lyrics site [stlyrics.com]!

  • Truck designation (Score:3, Informative)

    by B5_geek ( 638928 ) on Thursday January 05, 2006 @09:50AM (#14399618)
    "The evidence is compelling that body-on-frame light trucks cannot safely coexist with passenger cars under existing conditions. That problem is critical because so many light trucks are used nowadays as car substitutes."


    This might have something to do with the way that the government allows trucks to be classified.

    A truck is a utility/cargo vehicle, not a passenger vehicle.
    Trucks are required by law to have a 5 mile/h bumper, cars 10~15mile/hour.
    Fuel effiency/emmisions standards are not as stringent on cargo/utility vehicles.
    Mini-vans are also classified as utility/cargo vehicles.

    The only reason that there is an appearance of improved saftey is the higher kinetic energy + higher sitting position that these monsters have over a standard family-sedan.

  • Crash Ratings don't say what you think (Score:5, Interesting)

    by CFD339 ( 795926 ) <{andrewp} {at} {thenorth.com}> on Thursday January 05, 2006 @10:21AM (#14399826) Homepage Journal
    As a firefighter and first responder I can state that there's a big problem with the safety crash test ratings most consumers see. These 4 star and 5 star ratings don't tell the real story at all.

    These tests emphasise not just the human safety but also the cost of repair. To some extent, the cost of human repair is the factor added to the vehicle repair to make the rating. Interesting data, but not what most of us care about, and it results in very poor decision making information.

    Example: I have seen personally how effective "crumple zones" combined with airbags and safety brackets on hoods which prevent the hood from sliding directly back into the windshield in the case of a head on collision can work. I see completely destroyed cars all the time where the occupants are well protected and suffer only minor injuries. That's because much of the force of impact is used up in the act of crumpling the car. These crumple zones are amazingly effective.

    The problem for insurrance companies is that crumple zones and the like TRADE vehicle damage for human damage. The low-speed destruction of bumpers, fenders, hoods, and entire engine compartments mean that these cars are a "total loss" much more frequently.

    If you REALLY want to promote SAFETY -- and like me, you could care less about the damage to the vehicle if the humans are better protected -- than we need a safety rating system which ignores all things other than damage to the occupants of the vehicles.

    AP

  • low quality vehicals (Score:3, Insightful)

    by plopez ( 54068 ) on Thursday January 05, 2006 @11:07AM (#14400144) Journal
    Remember that one of the main reasons that SUVs were sold was that they exploit loop holes in pollution, safety and fuel efficiency standards. They are by their very nature low quality vehicals.

    Minivans were the same way until too many people were killed and the rules tightened. If you take a close look at modern minivans they are essentially reinventing the station wagon.

    Instead of exploiting loops holes, non-US manufacturers developed hybrids and high efficiency vehicals. SO now while US car companies are in trouble, foreign car companies are gathering up more market share. Just another sign that US business leadership is screwed. No vision, no intelligence, no ability or concern that we have known that world oil productuion would peak about 2005 (we have known this for about 30+ years). Just business as usual, play golf, out source and go for the short term.

  • Size is important. (Score:3, Interesting)

    by MaWeiTao ( 908546 ) on Thursday January 05, 2006 @11:18AM (#14400244)
    I personally hate SUVs. I think the fundamental problem in the United States is that drivers licenses are given out too easily and the base license gives a driver access to too many different kinds of vehicles. SUVs should require special licenses with extensive driver education.

    The problem comes down to driver ignorance and stupidity. This, however, isn't something unique to SUV drivers. Around where I live there have been countless idiots crashing into various objects in their beat-up, riced-up small Japanese imports. The city can't do anything to beautify the city without one of these morons coming along and destroying it. They sure do a good job of flipping those cars over too.

    That said, mass is a huge factor in determining passenger safety. Of course there are situations where people in a smaller car fare better than in the larger car, but that's the exception.

    We have all these crash tests which award the same high marks to a small car that they do to a large car. But these tests are performed under controlled conditions in the kinds of impacts people rarely encounter in real life. These tests are also conducted at relatively low speeds. The kinds of speeds drivers on the road are exposed will completely destroy a car regardless of all the safety features car makers install. And a driver in a large car has one simple advantage: there is more of the car to crash before the impact reaches the driver. I've heard from a few sources that a driver in a small car is up to 13 times more likely to die in a small car compared to a large one.

    Of course, if you're driving something as poorly built as that Jiangling nothing will help you, but that's another story. I'm surprised that Europe, with all it's regulations even allows the thing to be sold there. Then again, considering some of the things I've seen on the road there, it's not too surprising. The US is fairly strict. The ride height for the new Golf GTI was raised .5 inches to meet US bumper height regulations. And there are countless other vehicles not allowed here because of things like lacking 5mph bumpers. I guess the US government needs to make up for the fact that Americans are generally poor, irresponsible drivers.

    • Re:Size is important. (Score:3, Interesting)

      by b0s0z0ku ( 752509 )
      Of course, if you're driving something as poorly built as that Jiangling nothing will help you, but that's another story. I'm surprised that Europe, with all it's regulations even allows the thing to be sold there. Then again, considering some of the things I've seen on the road there, it's not too surprising. The US is fairly strict. The ride height for the new Golf GTI was raised .5 inches to meet US bumper height regulations. And there are countless other vehicles not allowed here because of things like

  • Body-on-frame vs. Unibody construction (Score:3, Informative)

    by Faeton ( 522316 ) on Thursday January 05, 2006 @11:29AM (#14400355) Homepage Journal
    This is an interesting article not because of the SUV vs car crashups, but an overall look at how techniques of making cars can create a disparity between 2 automobile classes.

    The last 25+ years, there has been a huge push for increased gas efficiency for cars, due to public consciousness, laws, etc. The easiest way to do this is to move less mass, and thus, the unibody car design is pretty much standard across the board for cars. I believe the Ford Crown Vic was probably the last car to be built using body on frame. But before this period, a vast majority of cars were built using body-on-frame, as it was easy, robust and survived crashes well (think of the boats like a Buick Estate).

    Trucks are govern by a different set of rules, and technically speaking, cannot transition to the unibody design that well for practical purposes. The loads they are designed to haul and tow (whether or not they do that in real life is irrelevant) demand that a body-on-frame design be used. There are exceptions like the Honda CRV, the 99-04 Nissan Pathfinder, the new Honda Ridgeline, but in the vast majority of cases, they use body-on-frame.

    So, over the last 25 years we've created 2 classes of vehicles. Unibody and Body-on-frame. The article suggests that this class difference cannot be reconciled and needs to be eliminated. But we all know that this won't happen, at least not right away. It seems like Honda is the sole pioneer of this conversion, and it was limited in part by it's lack of experience with the body-on-frame design. We need to encourage more companies to try a different route, and use more of the neat materials that science has given us in the last 25 years to bridge that gap.

    Think we're still getting light? Then look at motorcycles and how they've embraced technology far better than any car out there. Ever wonder why the spark plug is so big in the car? Ever wonder why car batteries use 19th century technology and a wimpy voltage? It was because of standards created long ago, where they didn't care about size and weight and didn't have the materials andn technology that we do now. The cost and weight savings are all within grasp. Someone just needs to take the lead.

    • Motorcycles (Score:3, Interesting)

      by b0s0z0ku ( 752509 )
      Then look at motorcycles and how they've embraced technology far better than any car out there.

      Sort of. The ignition systems, engine designs, suspensions, and brakes of bikes are often more advanced and weight-optimized. However, many bikes still use carbs instead of fuel injection since the pollution standards for bikes are laxer and it's expensive to make a fuel injection system that works well at over 10k RPM.

      Furthermore, bikes don't normally last as long as cars (100k miles is a long lifetime for

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