Disobeying The Laws of Physics

AccelerationYou may be able to disregard the rules in the Motor Vehicle Act and survive, but flouting the laws of physics when you drive will eventually result in a collision. I spent a decade dealing with concepts like perception - reaction time, coefficients of friction and maximum acceleration when I did a forensic examination of a collision scene. This gave me some insight into what you can and can't do as a driver and the need to never put yourself in a position when your vehicle tried to ask more of the laws of physics than they would allow.

The driver I watched yesterday either had no consideration for the physics involved in driving, had a very high risk tolerance or both. He was following a larger vehicle travelling 90 km/h with what looked like enough room to comfortably parallel park between them had they been standing still. I'm always happy when these drivers roar off into the distance and are no longer near me. I guess my tolerance of risk is not a high one, particularly when the risk is imposed on me by others.

90 km/h is 25 metres per second. Accepted perception - reaction time in collision reconstruction is 1.5 seconds. That means this driver travels 37 metres between the time something happens and he first applies the brake. No slowing has occurred yet. If the vehicle in front slows suddenly, a crash is inevitable.

Not a problem, I'll just steer out of the way you say. Remember that perception - reaction time? It means that you will just begin to turn the steering wheel after having travelled that 37 metres. Again, a crash is inevitable.

The vehicle in front doesn't have to slow to be a problem either. It may be blocking your view of what is ahead. If the driver waits until the last minute to move out of the way of a hazard, we're back to that 37 metres or 1.5 seconds again. Are you feeling like a crash test dummy yet? The laws of physics are not forgiving.

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Tail gating

Tail gating is an all too common practice on the main roads of Metro Vancouver and on the freeways of BC. 

On the main roads of Metro Vancouver I believe many drivers tail gate to prevent other drivers from cutting in front of them.  Cutting in front of other vehicles with only a few inches to spare and often without signaling is dangerous and rude.  If these drivers were pushing a shopping cart would they cut in front of another shopping cart in a line up?  Likely not, because others would speak up.  But inside their vehicle these drivers feel entitled to cut in and they are often quick to extend their middle finger if another driver honks his displeasure.

On the freeways of BC I believe many drivers tail gate, not to prevent other drivers from cutting in front, but to pressure the driver in front to go faster or move to the right lane.  Some drivers may tail gate so they are in the "slip stream" of the vehicle and front.  They seem to believe that avoiding the head wind will save on fuel.

Regardless of the reason for tail gating, it is a dangerous practice that, sooner or later, will bite those who do so and, unfortunately, other drivers in the vicinity.


     Tailgating is unfortunately quite common, especially on multilane roads in B.C.  The new, Keep Right Except to Pass law, should go a long way to alieviating this, as drivers are made aware that the left lane is for passing, not continuous driving, regardless of speed, thus preventing bottlenecks and driver frustration.

     The rule of thumb for a safe following distance is generally accepted as being 2+ seconds, regardless of speed, and more in poor weather conditions due to increased stopping distances.  This guideline used to be part of public service announcements many years ago, but I'm afraid all too many drivers are currently unaware of how close is too close.

Bumper Sticker

I have often thought of making a bumper sticker that reads :

"The closer you are, the slower I will have to go."

It just makes sense !

What doesn't make sense are the rubber neckers who slow down to look at the carnage from a highway  crash, then speed away, dodging and weaving for "position".

The Main Problem is Driver Attitude

I agree totally with your opinion on impatient drivers driving to closely. The calculations you stated are great, however does not solve the problem. Any police officer observing this type of behaviour should stop the tailgater, Give them a steep fine and should take away the offenders license until he has gone to a defensive driving class. I personnely would rather see a jail time, instead of fine to get the message across.

Also, on driving to slow in passing lane. I personnely drive in the right lane at the suggested speed limit and only use the left passing lane when required. Most of these impatient drivers that have to drive faster than the posted limits, somehow believe that they will get to their destination a few seconds faster than the traffic on the right lane doing the speed limit. Not true within the city limits. Often, these speedy drivers end up at the same red light I do.

Also those drivers that end up behind a slower vehicle in the left lane don't know the reason for it. Perhaps that driver is going to make a left turn in the next few blocks and doesn't want to leave the lane change for the very last minute. Many times I have seen vehicles in the left lane bumper to bumper, without leaving any room for a person in the right lane to get into that lane to make an upcoming left turn. However, if this driver was not intending to turn left soon, then he is in the wrong lane.

Finally, should we be concentrating on giving bad drivers tickets or be looking at better ways to resolve the issue and  perhaps save some lives. Perhaps automatic licence suspensions which double if driving while prohibited, to possible jail terms.

Our main overall goal should be to get ignorance off the road. Bad and impatient drivers should not be allowed to drive until they go through a defense driving school or some method of attitude adjustment, before they are allowed to drive again. Driving attitudes are the root of bad decisions drivers make. Instead of concentrating on speeding tickets, impaired drivers, etc., lets fix the main problem. Driver attitudes.

An Ongoing Problem in the Lower Mainland

As many BC drivers are aware, this problem is near-universal on the Trans-Canada between Chilliwack and Vancouver during all busy hours.

In attempting to maintain a sane following distance, I continually lose ground due to drivers from the left lane zipping in front of me because there is "space" for them. I must therefore slow down and increase my following distance accordingly, only for the same thing to occur repeatedly. I tend to give myself plenty of time to get somewhere, so I'm not upset about losing a few minutes; rather that so many people seem to think that this is acceptable behaviour on the road!

It seems almost a daily occurrence that there is an accident somewhere along the route slowing down traffic, and I'll bet that most of them are due to tailgating.

Almost Like Driving in Reverse

I agree with you and have experienced exactly the same thing. It's almost like leaving the space is an invitation to fill it and they more often than not fail to gain ground by doing so.

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