Rick Curtis wrote:
Essentials of a Marine Boat Alarm System

How To Avoid The Realization That Your Boat Insurance Company Isn't
Your Friend.

by Captain Dan Donaldson

Over the last couple of years it has been my awakening to have seen 3
boats sink in our 40 slip condo marina. As a boat owner, if you have
ever witnessed a boat sinking at the dock you know it will scare you
into action. In all three cases the boat floated fine with little or
no indication that momentarily it would find the bottom.

The last sinking was a 43' Wellcraft Portofino parked right behind its
owner's condo unit. I walked by the imminently doomed Wellcraft on my
way to the swimming pool and it half registered that the boat appeared
to be listing ever so slightly to starboard. Without giving it much
thought, as I walked by the boat it started gurgling and within 30
seconds it found its place on the muddy bottom with only the bow
exposed. I ran to the owner's condo and found the owner sitting in
his home office, not more than 50 feet from his boat, at his desk with
a full view of his nearly disappeared pride and joy.

Snip

It's nice to live in a latitude (56 deg N.) where the summers are short, and
most boats have to come out of the water end October until the following
Spring!

I didn't realise that much of your concern arises out of the vessel's
prolonged immersion, with the consequent need for fairly frequent year-round
attendance.

Our main concern at this time of year is of water freezing in the engine and
fresh water tanks, finding a warm enough day to commence the annual
bottom-scraping task, and making sure the boat is not blown off it's cradle
by a violent storm!

Your excellent treatise on this system has been noted here in the UK. No
doubt the company concerned can export such a system, even for use during
4-5months we are not shivering and dreaming of better days on the water
3-months hence!

It would be interesting to have your comments once the system has completed
a couple of years in use, and to see whether any unforseen snags have arisen
in that time. Incidentally, a lot of marine burglary can be prevented by
having as many systems as possible installed on a laptop, which can be taken
ashore at the end of each trip, but that's another story!