By on March 8, 2011

Another day, another way to die in a car… and this time, the IIHS blames weak safety standards for semi-truck underride guards for this mangled Malibu [report PDF here]. The IIHS argues that

Under current certification standards, the trailer, underride guard, bolts, and welding don’t have to be tested as a whole system. That’s a big part of the problem. Some manufacturers do test guards on the trailer. We think all guards should be evaluated this way. At the least, all rear guards should be as strong as the best one we tested

But the best underride system they tested (a Wabash) still would have likely decapitated the Malibu driver in a 30% offset hit at 35 MPH. So even if government enact the stricter standards endorsed by the IIHS, you’ll still have to hit the rear of a semi truck fairly square-on in order to reap the benefits. But of the 2,200+ passenger car occupants who died in crashes with large trucks in 2009, we have no idea how many were square-on rear crashes like the one tested. And until the IIHS gets the government to regulate bumpers height, crash test-derived standards will always be less effective when they leave the lab and get into the messy real world of the American road.

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37 Comments on “Be Careful Around Those Semi Trucks...”


  • avatar
    jmo

    But of the 2,200+ passenger car occupants who died in crashes with large trucks in 2009

    Did you see the interview with the woman who had her entire lower face torn off?  You need to keep in mind not only the 2200 fatalities but the 10s of thousands of sever injuries.

  • avatar
    aspade

    Semis don’t exactly stop on a dime.  If you manage to rear end something that takes 400 feet to come to a stop maybe you deserve to be decapitated.

    • 0 avatar
      friedclams

      No allowance for weather conditions, accidents, sudden stops due to mishaps, etc.? Driver negligence isn’t always the cause.

    • 0 avatar

      “semis don’t stop on a dime”
      They do if they run into another one ahead of it.

    • 0 avatar
      Jimal

      I believe this is a jumping the gun proactive response to any comments about the dangers of hypermiling. aspade is correct as are friedclams and Paul.

    • 0 avatar
      PeriSoft

      You have to consider this from aspade’s point of view – which is, as far as I can tell: The government does everything wrong. When government does something right, it’s just because the government failed at doing something wrong. And people in severe car accidents deserve what they get – at least until such time as aspade himself is in a severe accident. Then it’s gonna be law-and-order time for the other party, I suspect… meted out by the government.

    • 0 avatar
      ihatetrees

      Give aspade a break. He wrote, “maybe you deserve to be…”
       

  • avatar
    friedclams

    I disagree with this editorial. I think the video shows fairly convincingly that those guards are obviously failing at their purpose. They are already mandated, so I don’t think this is an example of the IIHS trying to create a new regulation.
    I would assume that the cost differential between the Wabash guard and the lesser ones would be pretty inconsequential in terms of lives lost, my hunch is that the cost/benefits makes sense on this one… even if a guard needed to be devised that could address offset impacts. I think this is low-hanging fruit.

    • 0 avatar
      Alexdi

      Agreed. This should be regulated. The guard should be redesigned to wrap around the sides. The cost difference would be minimal, it would solve the offset problem, and the strength of the guard in full-surface collisions would be improved significantly.

    • 0 avatar
      gslippy

      Agreed, also.  2200 lives is a lot, and it’s a significant portion of those lives lost each year.
       
      This is a relatively simple engineering issue that could be resolved without much effort or extra cost to each trailer.
       
      This isn’t the old “Hummer vs Metro” story, where we rehash the consumer decision to buy small vs large cars.  Rather, it is an obviously overlooked safety issue in an area in which all consumers are at risk, and which mere behavior changes cannot resolve.

    • 0 avatar
      Jimal

      This is what NHTSA should be bothering with, not back up cameras and cell phone jammers.

    • 0 avatar
      PeriSoft

      +1 as well. This is the kind of thing where regulation works: An inexpensive fix that will get ignored or overlooked without a nudge from an external source.
       
      And this is a quintessential example of something that consumer decision can’t fix. With car safety itself, you could (though not always correctly) say that the consumer can choose to get a safer car.
       
      But car buyers can’t choose to have safer trailer guards, and the people making trailers have no commercial incentive to help out people who are buying cars. Pressure via capitalism works great if consumers are informed, educated, and have real choice; in this situation, there’s no way for consumers to either buy a safe alternative (unless they all buy Peterbilts) or to affect the design of safety guards via commercial pressure.
       
      This is a perfect example of a situation where regulation fits.

  • avatar
    mikey

    In my former life as a shipper reciever for GM, we used that safety bar to lock the trailer to the loading dock.

    Once in awhile, despite the best intentions somebody “forgot” to unlock the trailer. The trucker releases the clutch and 800 hp is applied to the bar. The bar might slightly bend. However the locking mechanism is usually destroyed rendering that dock unusable.

    The result is, maintenance people are called in, and b/c poo flows downhill, all dock personal have to sit through a safety lecture.

    The point of my story is…. “human beings make mistakes” if you rear end a tractor trailer with your Malibu…you lose. If you rear end a Miata with your Suburban the guy in the Miata loses.

     Sh— happens!

    • 0 avatar
      friedclams

      Mikey, just curious (and OT), why would you lock the trailer like that? To keep the trailer from rolling? If so wouldn’t chocks (sp?) have served the same purpose?
       
      I remember one time in MI I flagged down a trucker whose guard had been bent, thereby rubbing against his rearmost tire, which was smoking! Was he coming from your plant? :-)

    • 0 avatar
      Toad

      You lock the trailer to the loading dock so that the trailer cannot be pulled or roll away from the loading dock while it is being loaded or unloaded.  This keeps forklifts from falling into the space between the trailer and loading dock.

  • avatar
    JMII

    All these safety regs and yet this one continues to slip by almost unnoticed. Semis and jacked up 4x4s are on my personal list of “death traps in waiting”. I hope they do something to make them safer.
     
    aspade – I might be able to stop in time but what about someone behind me in traffic on their cell phone? They are not paying attention and plow into me, thus pushing me UNDER the semi. Don’t tell me it doesn’t happen, my wife was involved in such a crash, luckily it wasn’t a semi but her car was pushed under another vehicle. Thankfully it occurred at low speeds so no injuries… but all the damage was done to the HOOD, her bumpers never touched the vehicle ahead. The nature of stopping means the front end nose dives so if anything rear bumpers need to be even LOWER.

    • 0 avatar
      SunnyvaleCA

      +1
       
      Not only should semis and jacked up 4x4s be made more compatible, but all the other “light truck” vehicles on the road.  If those vehicles need 2 feet of ground clearance for off-road,then that’s fine… adjustable suspension and or removable (low) bumpers. Lower the headlight height while you are at it–the fog lights in Escalades are just about right for on-road low beams.

    • 0 avatar
      cackalacka

      +2, although, to be fair, semis do have a functional use in society.
       
      Has anyone invented a rear-mounted laser-beam to direct at light truck drivers with aftermarket Xenon headlights yet?

  • avatar
    mikey

    @JMII….The great news, is that your wife wasn’t hurt. The bad guy here was not your wife, or the guy she got pushed into. It was the guy ,not paying attention. Thats were the problem lies.

  • avatar
    Jerome10

    Hmm.  This is one of those things I think I actually don’t have a problem.  Particularly spending the past year in Europe, I notice their trucks are much lower to the ground.  They at least LOOK more compatible in a crash with a car.  Ours always look like you’d ride right under them, regardless of where the impact takes place.
     
    Could there actually be fuel saving/aerodynamic advantages to fixing this issue as well?
     
     

  • avatar
    tekdemon

    Saw one of these the other day where a car driving on a snowy road had an offset accident with a tractor trailer…it was really ugly since the entire right side of the car was essentially annihilated…we all hoped that there wasn’t anyone in the passenger side since it looked pretty unsurvivable.  

  • avatar
    mikey

     Is there any railroad tracks going into Wall Mart? ….Right if you have it, whatever it is, it came by truck. So lets regulate trucking even more. We can drive consumer goods a little higher.

  • avatar
    CarPerson

    Sad to see that when the IIHS possibly comes up with something good people remember the repeated releases of the pro-traffic camera studies that TOTALLY FAIL close scrutiny.

  • avatar
    mikey

    Truckers spend a lot of time by themselves. When they get to the docks,they love to talk. I spent eleven years doing paperwork and listening to truckers stories.

    One common theme……About 20% of the people on the road shoudn’t have a drivers licence.

  • avatar
    Highway27

    The only gory film we saw in Driver’s Ed (in 1987) was “UNDERRIDE!” which basically showed a bunch of cars that had smashed into trucks with these inadequate guards.
     
    I don’t know if any additional ‘guard’ put on the bottom of a semi-trailer is going to ever prevent this occuring, since the real problem is the bottom deck of the trailer at passenger car head height.
     
    I do wonder how much could be helped by education of drivers: Increase your following distance!  No, it won’t fix everything, but it’s something that’s actually achievable.  Yeah, if we increase regulations on trucks, that might help some.  But it will also cost everyone.  And will the benefit outweigh the costs?  And even then, better education about following distance and paying attention to the traffic around you will still have a benefit.
     

    • 0 avatar
      psarhjinian

      I don’t know if any additional ‘guard’ put on the bottom of a semi-trailer is going to ever prevent this occuring, since the real problem is the bottom deck of the trailer at passenger car head height.

      I don’t think you’ll ever see this fixed because we’ve got a more or less standard dock height that most trailers are built to and changing it is not an option.

      Moving trucks (which are never docked) have a much lower floor.  They’re more aerodynamic, too. Anyone know if European and Asian docks are lower to ground there?

    • 0 avatar
      PeriSoft

      Good luck increasing your following distance on the Long Island Expressway or I81 during rush hour. You’ll end up going backwards.

  • avatar
    YYYYguy

    Don’t mandate new bumper guards, simply require a rear set of wheels to be within 2 feet of the rear of the trailer.  Simple problem, simple solution. 

    I think given the choice, most folks would rather crash into air and rubber rather than slide under a truck.

  • avatar
    mikey

    With a 53 foot tandem trailer the rear wheels will slide back. At GM we demanded that the driver slide his wheels, before we would put an 8000 lb lift truck on the trailer. However the driver had to re position his wheels before going back to the highway. I have no idea why.

    • 0 avatar
      Bimmer

      I guess it has to do with maneuverability and weight distribution. With wheels closer to the truck on the trailer, it makes smaller radius turns (just look on the large school bus rear overhang).
       

    • 0 avatar
      Toad

      Speaking as a truck owner:  Weight distribution is the answer.  If most of the load weight is in the front of the cargo area the trailer tandems can be slid forward to put more weight on the (back) trailer axles, and vice versa.  Highway weight restrictions dictate how much weight can be on each truck axle, and sliding the trailer axles evens out the weight.  You also want weight distribution as even as possible to increase traction and prevent skidding/wheel lockup when braking.
       
      Mikey, when you were loading trailers the tandems need to slid all the way back at the dock so they do not act as a fulcrum when the loaded forklift enters the rear of the trailer.  Otherwise, when it is entering the back of the trailer the weight of a heavy forklift plus the pallet it is carrying could lift the front of the trailer like it was a giant teeter-totter, causing the forklift to slide back out along with any cargo in the trailer; havoc ensues.
       
      In addition, you cannot have the ICC bumper too low or it will scrape pavement on an incline when the rear tandems are slid forward.  You see these scratches in the pavement near steep railroad track inclines.
       
      This proposed rule may be a good idea, or it may not.  For example, some states have different speed limits for trucks and cars because it sounds intuitively good, but every bit of research on the subject shows that the resulting “speed differentials” are more dangerous than trucks going at the speed of traffic.  The bumper rule may fall into the same category.  We need research, not feel good legislation/rule making.
       
      PS: I hate the jacked up 4×4’s on both safety and aesthetic grounds.  They handle worse than my dancing and look at least as stupid.

  • avatar

    FWIW, the Canadian regulations on the strength of these back undercarriage assemblies are different and more stringent than the US ones.

  • avatar
    roger628

    Well it’s better than none at all, which is the way it used to be until the death of Jayne Mansfield spurred the legislation for them  in the first place. Read more about it here.
    http://www.findadeath.com Sorry can’t direct link the page-Look her up in the directory if interested .

    • 0 avatar
      friedclams

      Paul wrote a nice article about Jayne Mansfield and her Buick, see below. I didn’t realize her death is what spurred the regulation, thanks for that.
      https://www.thetruthaboutcars.com/2010/04/curbside-classic-1967-buick-electra-225-the-jayne-mansfield-of-convertibles/

  • avatar
    krystalkid

    That under-ride guard is set at 22″ from the ground to the bottom of the bumper by the Federal Government.  But there are a lot of pickup trucks you can drive off the lot with bumpers higher than that.  You are two times more likely to die from a post collision vehicle fire to a pickup truck (because the bullet vehicle underrode the bumper and hit the gas tank) than backing over someone with it (yet we have back up sensors) – so how about an under-ride guard for pickup trucks like these energy absorbing ones from sparebumper.com…

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