Part 6
- Kapitan Bill Thomas

Bill Thompson adds a postscript to his recent series on submarines.

Submarines. like many  warships, have a high length to beam ratio which inhibits their ability to turn in tight circles. U789  suffered form this drawback also and I decided to  eliminate this it if possible by having the propellers driving in opposite direction on the turn Any twin model would find this facility valuable. The ideal ,solution is to have independent motor  control, but this involves two channels, two servos and two sets of switchgear or speed controllers. This means more expense, and more importantly in a submarine, hull space! I was and am acutely short of both commodities and decided to  make one of my rare ventures into the electro-mechanical gadgetry, using the rudder servo to operate micro switches in the motor circuit when the output arm was at the end .it's travel, or when the rudder trim was used. For those of you who dislike formal wiring diagrams as much as I do, the wiring is displayed pictorially. When the  devise was assembled, I swallowed a few tranquillisers and headed factor lake to try it cut.

 The trials were an instantaneous success of dazzling brilliance! When propulsion and full  rudder were applied, U‑789 spun slowly in her own length. I tried manoeuvring astern, a feat often justifiably feared  by many competitors. No problem. I planted some sticks in the lake and practised steering between them. I as stunned! This was no mere model. this was a  prize-winning machined! Here, I had a boat which could sail with impunity in the wildest conditions, which could slither snake-like through the narrowest gate, with her 5in beam and now could pause in front of the gate and pivot at will to select the perfect approach angle. My eyes narrowed, my jaw tightened. I would show these Englanders the futility of opposing U789.  All opposition would be  obliterated!

But alas, my dreams of shelf upon shelf of glittering trophies were dashed. By unfortunate chance, the rules governing Club Scale Competitions were adjusted round about this time, and U 789 was excluded from entity being 3/4in too narrow in the beam. I  accepted the setback gracefully as being in the best interests of all concerned. especially my good self. For after half a dozen consecutive wins, my gloating would have become insufferable and my trousers would have been forcible in public. In any case, I had other fish to fry Automatic depth keeping! A problem I stall have not solved.

In a way, I hope I do not achieve complete success, as it could make submarine operations boring, but it's fun trying You are all invited to join  in with ideas!. Could a pendulum linked to the bow planes in  conjunction with a pressure  switch from a washing machine be a starring point? But no dragging around of floats on string  mark you, or 3ft. long periscope!  Write with Your solutions to Model Boats. Winning entry gets a signed photo of Me Kapitain Thompsen!

How about that for an incentive. "Kamerden To the drawing boards!"


    Back to U 789 index