Tuesday, September 10, 2019

Sometimes it's only when you come to teach someone something that you find out if you really understand it yourself.  A couple of weeks ago when our friend Phil was borrowing Herbie for a few days I was explaining to him the best way to steer the boat out of the tight marina entrance and on to the canal.

Turns like this, effectively T junctions, make you think.  When we were moored at Crick, we often used to sit on our grassy knoll watching the boats exiting from the marina.  It was a tight turn, especially for longer boats and we saw a good many boaters make a pigs ear of it.  Funnily enough, the bow thruster users did no better, often worse in fact, than those with only tiller steering.

So I was explaining the technique to Phil, who is OK at steering, the T junction technique, which he quickly understood, and he said "Funny isn't it, it's counter intuitive."  Then I realised that it probably was.  I suppose that's because we're all used to driving vehicles with front wheel steering.  Here's a picture of our marina exit with a boat on its way out, intending to turn left up the canal.

Now if we were in a car, to give ourselves plenty of room to turn we'd stay towards the right of the exit lane, but in a boat it's just the opposite.  Because the boat pivots about its centre, we need room for the back to swing out right when we turn left.  If we hugged the right side of the exit we couldn't begin to turn until the boat until the bow was right across the canal and we'd be in a pickle.  So we have to hug the inside of the bend.

Similarly on tight canal bends we have to keep away from the outside of the bend.  I expect we've all got that wrong sometimes  and found ourselves stuck on the outside of the curve, having to jump off and give the bow a shove.  I know I have anyway.  It's especially easy to do on the second part of an S bend.  In the picture here, the boat can't turn any more and is stuck on the bank. (Unless of course you have a throw buster).

One on the stretch between Braunston and Wigrams Turn springs to mind, where there is a bridge over the top.

Tillers of course are notoriously counter intuitive until you get used to them.  I found the trick of teaching it when Grace (about 8 by then) was learning to steer. I tried various ways of explaining it, including the amusing old adage, "Point the handle of the tiller at the thing you don't want to hit."  In the end, the thing that clicked with Grace was,"As soon as the front of the boat wanders off the line you want, move the tiller handle in the same direction as the front is wandering."  It really works, and now she is a good little steerer.

Now, should you ever have the misfortune to steer a boat like the CRT ones with an archimedes screw propeller and a steering wheel, I'm afraid I cannot help you.  Despite some training and many hours of moving these things, I never really got the hang of it and wandered up the canal like a drunken man weaving fro side to side.  Half of the problem is that the steering wheels have several complete revolutions from side to side and there is no marker to tell how many turns you have made, so you're never sure if you're steering straight or not. The worst is when you go into reverse to stop, everything seems to work the wrong way. I think if I had one of these boats I'd want a brain reset.

Anyhow, there it is.  I know I'm not teaching you anything, but I found it interesting to have to find words to explain these things to 'learners' as it helped me to understand what I'd been learning intuitively.