[VAC] Re: winter towing

["Richard P. Kenan" <as5368@xxxxxxxxxxxxxx>]

Bob:

         I agree, apples to oranges.  Well put.
         Unfortunately, Don's demo could not be applied simply to an 
articulated vehicle and give meaningful answers.  Don uses a toy car on a 
ramp, and runs it down freely; then with the front wheels fixed by a rubber 
band, so that they slide; then with the rear wheels fixed to slide, again 
with a rubber band.  The result is clear and more or less independent of 
residual (sliding) friction on the fixed tires - fixing the rear tires 
causes instability, fixing the front ones does not.
         With a trailer on dry pavement, even if the trailer tires skid 
they will still provide a stabilizing frictional force because sliding 
friction is not zero.  So, if the tow vehicle is not skidding too, a 
skidding trailer could still be stable.
         On ice, the residual friction is much reduced, nearly to zero, and 
the skidding trailer will probably try to jackknife.  If you are able, 
accelerating the tow vehicle (but not enough to break *its* tires loose) 
should help; even without much tire friction at the road, the trailer 
inertia will still tend to straighten the rig out.  Trailer brakes are 
unlikely to be very effective on "glare ice," although every little bit 
will help.
         Running on packed snow rather than "glare" ice, especially if it 
has developed a rut, should give more stability.  Your experience in Alaska 
seems to bear this out.  Glad you had no trouble.
         Seems to me like "stay at home if you can" would be good advice.

>No way did I want to have my rig all over the road in -40 weather.

         Yeah... the weather itself is a life threatening at that temperature.

- Dick
(5368)