Trial Launch and Reteieve

Refurb mostly finished I turned my attention to the trailer and launching procedure.

The trailer is a tipping type, or break back trailer. The drawbar, normally rigid is, while still hitched to the car, partly unpinned and allowed to pivot downwards. As the loaded section of the trailer now has a weight bias towards the aft, the trailer tips aftwards, the extra gradient thus given to the the boat helping to initiate the launch. Control would then be via the winch so the boat could be lowered safely down the extra gradient.

That’s the theory. Load calculations followed the theoretical analysis and I decided against using this trailer in such a manner.

I had my doubts about this from the start since it’s such a heavy boat and frankly sounded positively dangerous thing to do with a one and a half tonne boat. I reckoned with a lighter boat, say 750kgs this would have worked like a charm and I’ve seen videos of this kind of launch on you tube that make it seem effortless.

So the plan was to float on and off, which meant getting the boat out about 12 feet further than possible without getting the wheels wet.

We booked a slot at a local marina on the nearest canal to perform a trial launch and retrieve. Something that caused a lot of interest at the time since it’s an unusual craft to enter the canal. So embarrassingly we had an audience. It is after all a trial in order to determine the process and make sure everything went according to plan and of it didn’t, to make the necessary adjustments to the trailer and/or the procedure.

So what I learned from this excercise was when launching there’s no way to push the boat off it’s rollers it’s just to heavy. The trailer rollers are not designed to take this weight and are partially crushed and simply refuse to roll. So the only option is to float off. Adding more rollers might help.

When retrieving a slightly different scenario, it is necessary to get the boat lined up on the rollers. This turned out to be tricky and several attempts would be necessary with the potential of incurring some damage if not aligned properly. The trailer does have launching guide poles, but they only positively engage with the hull sides when almost fully loaded on the trailer so there’s nothing to stop the boat moving around and several attempts had to be made to get the keel aligned with the rollers.

Both these operations require the trailer to be in much deeper and much further into the water than would be possible with the trailer still hitched to the car. To push the rig out further an improvised launching pole was used to test this out but this would be replaced with a proper one once this method had been proven.

So the trial went ok and a number of lessons learned. A bit of a rethink was needed of the process was to work in a reasonably short time. I particularly needed to think about alignment especially on retrieve. And the launching pole needed to be upgraded. All in all a very useful exercise.