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Fatal Rear-end Collision Reported on BNSF

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There are different ways to dissipate the impact energy of a collision, but all of them utilize a cushion.  The cushion can be part of the moving object or a part of the object that is struck.  With energy-absorbing cushions on the back of highway maintenance trucks, the cushion is a part of the object struck.  The same is true with energy absorbing guardrail systems built up around concrete bridge columns. Likewise with an airbag where the cushion is part of the object, which is the steering column.  The moving object in the case of the airbag is the driver.   <o:p></o:p> On the other hand, in the case of shock absorbing bumpers on cars, the cushion is part of the moving object rather than part of the object that is struck.  Following the same principle, there are some rather outlandish proposals to add big airbags to the front of locomotives in order to protect pedestrians, which amounts to a cushion on the moving object.   <o:p></o:p> In a collision between railroad equipment, the impact-absorbing cushion is the softest part of either the moving locomotive or rolling stock, or the locomotive or rolling stock that is struck.  Usually, it is a combination of both, as in this case of the Iowa crash.   <o:p></o:p> Since the point of crash protection is to safeguard the crew personnel, it would be most cost-effective to place the impact-absorbing cushion on locomotives rather than on every freight car.  But the larger problem is the extreme amount of impact energy that needs to be absorbed when one train collides with another.  The amount of momentum energy in a 15,0000-ton train, for instance, is hundreds of times greater than what could possibly be absorbed in any reasonably sized locomotive-borne cushion.  When this coal train in Iowa plowed its way through all those flat cars of maintenance equipment, it was only moving 23 mph, when it first hit.        <o:p></o:p> The way to absorb collision energy in a train crash is to make the freight cars of the train being struck absorb all of the energy.  But you don’t do this by adding cushions to freight cars.  You do it by making locomotive cabs so strong that they cannot act as cushions by being crushed.  That way, all of the energy will be dissipated by the freight cars being struck.   <o:p></o:p> The problem is a little different in the case of locomotives striking other locomotives in head-on collisions.  But if the locomotive cabs are strong enough, they will not crush each other.  Both will be protected while the impact is absorbed by the trailing rolling stock.   <o:p></o:p> The locomotive frames are stronger than freight car frames, and locomotives weigh more than freight cars.  The only problem is that locomotives are as soft as freight cars in locations above the level of the frames.  So you have to provide a rigid structure that effectively raises the height of the locomotive frame at the front end where crash impact will occur.  <o:p></o:p> There is nothing technically difficult about this workable crash protection system, but it adds cost to the locomotive.  I would not be surprised if it increased the cost by 50%.  The added cost is not only in the extra steel and labor, but also in the engineering and design modifications needed to fit this crash protection into the locomotive.  Particularly problematic would be reinforcing the area around the windshield without significantly reducing the size of the cab interior or reducing the visibility.  So the real problem is paying for a system that should not be necessary if railroaders are doing their job.  I can see where railroad companies would come down on this.  The problem is that you have regulatory bodies that can call the shots, and for such organizations, it is so easy to be all about safety.  Public safety is the mother’s milk of growing bureaucracies.   <o:p></o:p> And when it comes to crash protection for railroad workers, nothing could so dramatically drive home the point that more is needed than this crash in Iowa.  They say that all railroad rules are written in blood, meaning that the need for them is unknown until someone is hurt or killed.  It is that way with most safety measures.  People need to be shown what can go wrong before they see a need to protect against it.  So I suspect that this Iowa crash will lead to a collision between the call for mandated safety features and the need to pay for them.
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