Before the 5th wheel, we used a steel flat deck trailer, with a straight hitch.  The deck had expanded metal on top.  This trailer seen many uses, including hauling gravel to Meziadin to pour cement footings for the new diesel tanks, in the mid 70's.  It was a killer trailer, since you couldn't get the load balanced on the trailer to give you the right tongue weight on the hitch.  Either it was too heavy or too light.  Both would spell disaster for highway driving.
      I remember the day Brian Wolfe and myself were told to go pick up the load of gravel and take it up to Meziadin.  We stopped at the cement plant, which was located across from where the travel bureau is now, and loaded up a yard or more of gravel.  As it turned out, too much for the axels, and in the wrong place on the trailer.
     As we took off on the highway, once we got to the 40-50 mph range the truck would get a terrible wiggle to it, and start fish-tailing.  With the electric brake control on the trailer, I was able to keep it under control on the flat, and we carefully proceeded at about 40 mph max.  Then came a hill, with an S curve thrown in.  Behind us an ICG Propane Tanker truck, and he was right on my heels.  I guess he got impatient, or seen impending disaster, but he started to pass me in the mid S.  The brakes wouldn't hold the trailer, and it started to fish-tail, bad!, so bad, at one point I looked in my driver's mirror, and seen the trailer, swinging into the other lane, UNDER the propane tankers belly, and then swing back, just as he passed.  Inches to spare, I am sure.  The propane truck floored it, to get away from me.  and remembering what Birke Brookbank told me, to stop a fish-tail, apply full power.  I did, and Brian thought I was crazy I am sure, since we were already going too fast to control this thing.  But it worked, the truck straightened out, and we hit the bottom of the S curve, and into the straight away, doing quite a speed.  But on the flat, I was able to slowly apply the trailer brake, to bring us to a stop, where we cleaned out our pants!
      I am not sure if Brian, or me, was more scared, but we came close to doing ourselves in that day.  We only got up near Brown Bear, and the wheel axle broke on one side, from the heavy load.  It was shortly after that, we got the 5th wheel trailer.  What a difference, you could load anything on it, anywhere, and it pulled like a dream.  Wouldn't mind having that trailer for myself today.  I always wondered what that Propane truck driver was thinking after that!