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[quote user="tree68"] A vehicle travelling at 70 MPH is covering 102.67 feet per second.  Per <a target="_blank" href="http://www.csgnetwork.com/stopdistinfo.html" title="http://www.csgnetwork.com/stopdistinfo.html">this site</a>, reaction time at 70 MPH will mean travelling 154 feet, with actual braking accounting for 234 feet, a total of 388 feet, well under your hypothetical 500 feet.  I believe those numbers assume an automobile and "normal" road conditions.  In addition, the site suggests that the gates generally take between 5 and 10 seconds before being fully lowered.  My own experience with local crossings indicates that the gates don't begin to lower until several seconds after the lights begin to flash. From all of that, we can conclude that if one were 500 feet from a crossing when the lights activated, travelling at 70 MPH, a driver should either be able to safely stop his automobile, or even clear the crossing before the gates were down if he maintained his speed. <div style="clear:both;"></div> [/quote]  <o:p></o:p> I need to clarify something about my example above.  I should have stipulated that it applied to a truck such as the one involved in the crash.  However, it is not an example based on the exact circumstances of the crash.  My example deals with what happens when such a truck approaches the crossing at 70 mph and the signals activate when it is 500 feet away.  In this example, there is no collision.   <o:p></o:p> The point of my example is to highlight a defect in the crossing setup.  However, this defect will not lead to a crash, but rather, it places the driver into dilemma, which might cause the truck to skid and jackknife.  The issue is a crossing protection system presenting a driver with a “red board” right in the face at 70 mph with the additional prospect of the gates lowering before the driver can get across.     <o:p></o:p> Regarding my 500 ft. stopping distance assumption:  <o:p></o:p> You are also right that the average stopping distance is 388 feet, but that is for cars.  The average stopping speed for trucks is 465 feet.  The category “truck” is broad, so I don’t know what how the stopping distance is affected by the range from large trucks to small trucks.  But I thought it fair to pick a round number of 500 feet, considering that this was a big truck, and it was pulling two trailers in tandem.  The actual stopping distance for such a truck is fairly likely to be higher than the average, and it might be much higher.  The driver skidded 320 feet and still has some speed left over.   <o:p></o:p> It may well be that the driver can get across before the gates are far enough down to foul the vehicle.  But a driver does not know that ahead of time.  The UMTCD says there must be at least a 3-second delay between the activation of the flashing lights and the start of the descent of the gates.  So an informed driver would know that he or she has at least three seconds for that to occur.   <o:p></o:p> But three seconds is not enough for the 70 mph road.  At the 500-foot example I have outlined, the driver would crash through the gates if he or she kept moving at 70 mph, or if he or she attempted to stop, but found that 500 feet was not enough room to stop.   Therefore, because the three-second delay is not enough, the owner of the crossing should have set the equipment to provide a longer delay.  However, there is no way for a driver to know what that actual delay is.  So a driver can only assume a three-second delay and hope for more.   <o:p></o:p> Therefore, I don’t think a driver is likely to know how much time he or she has between the activation of the red lights and the decent of the gate.  Any conclusion as to this interval must be an assumption unless you just might happen to be privy to the technical information for that particular crossing.  <o:p></o:p> However, in the final analysis, the questions of the stopping distance and the timing of the gate descent are beside the point because the driver cannot know the answer to those questions.  That is the point.  That is what produces a dilemma for the driver.  So it is not an issue of getting hit by the train in this example.  The issue is requiring a driver to perform a panic stop in what is fundamentally a life or death situation in the mind of a driver assessing what the signals mean.  From a driver’s point of view, he or she is confronted with amounts to a traffic light changing from green to red, with no yellow in between.    <o:p></o:p> According to your assumption about the gate timing, and your stopping distance, you concluded that a driver should be able to stop in time, and then you apply this to all drivers.  From that, you conclude that there is no issue.  But I asked what you would do if you were the driver, and you did not answer my question.  You have to put yourself into the position of a driver to understand my example.  You cannot just passively project your knowledge of what you think drivers should do onto drivers confronting this situation.   <o:p></o:p> So I ask again.  What would you do if you were driving that truck at 70 mph approaching that crossing and the lights activated when you were 500 feet away?  <o:p></o:p> So far, nobody has answered that question.  I can’t even answer it for myself if I were the driver.  The inability of anyone here to answer the question makes my point.    <o:p></o:p>  <o:p></o:p>
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