Hi Glen. In principle that should work, but in practice it may be harder
to implement. If you made something "breakable" and it got worn down or
weakened over time, would it still work?
My thrusters don't penetrate the hull (except for the electrical wires)
so a breakable shaft is still possible, but I'd be concerned about
reliability.
My thoughts gravitate more toward a release mechanism rather than a
planned " failure point".
With a breakable shaft, maybe you bump into something like a rock or even
the dock, and there goes your thruster.
My rear motor/rudder mounts could be adapted so they could drop free with
the removal of a pin where there's a 1/2 inch stainless bolt right now.
The side thruster/dive planes could be modified in much the same way.
Other than those two places, there's no where on my sub to snag something.
It's pretty smooth on the outside. I need to get some pictures up for you
guys, but it doesn't look much like a K boat. I have eliminated the legs/skids
because of the snag hazard and replaced it with a smooth keel shape which
doubles as the drop weight and has some rollers in it for moving the sub on
land and launching from a trailer. Not really anywhere to grab on that
thing.
Frank D.