Hatch-bars.....downside is if they can see you they may be able to shoot you, or get you to unlock the bars. Also denies rapid deck access to you, especially in case of fire, or using the outside
head. Still, a good thing, especially when you're not there, without turning the
cabin into a sauna.
Motion detector.....ultrasound detector like on convertibles? Could be a useful thing....but false alarms will make the thing annoying, or have the kid-crying-wolf effect. On the positive side, if you leave it set when you're away it could go off and drown out the
noise of windmills and halyards slapping, or the
dinghy wars between the sloopies & ketchies/rocnas & mansonites.
Deterrent....The Dog.....probably room for a thread about our furry friends. In my opinion, that wonderful nose and ear combo is hard to beat, possibly more important than the ripping-off-limbs ability. Plus,
dogs are just cool. Er, I hear sharks love them too, so careful when swimming....
Notification....I guess you mean alerting the world that something is amiss. As long as Mr Artillery doesn't think he's being shot at and hose you down.....or you set your boat on fire. Foghorn & Siren & Deck lights would be easier and less risky, and also last longer than a fleeting flare. Now a trip flare across the easiest access point, the sugarscoop stern or swim platforms, might be a nice Welcome Aboard surprise....as long as you remember to deactivate it on your rocking boat in the morning when you go for your morning ablutions. Revolver flares on the
mast....fire...short signal duration....still, would be an interesting setup, especially for illumination.
Radar....good, but false alerts/missed contacts. There may be other dinghies moving about, unless it is really isolated where it would be good idea. Hydrophones with
software recognition of
engine (ie not natural) noises, but that's my pet
project...
Innovation...by all means! But watch out for
radio operated stuff, such as someone opening their garage door on land....ooooh, looky, fireworks on a boat in the harbour.
Radio....wonderful idea. Comms are great....as long as nobody can listen in and get info on where the weak spots are, or join in the chat pretending to be someone else. Watch out for codes, especially when written, too obvious, too complicated, or past use-by date. Light signals (everyone kows morse and has a signal light and filters) and
flags don't need explanation to sailors, and the hydrophones are available at Micah's
Marine for a tidy, er, affordable sum.
But the one thing you missed is keeping the suckers off the boat in the first place...the world starts trespassing at the rail, not the hatches. Boarding net, like those compact luggage nets...preferably
not with a
DIY Ol' Sparky enhancement either, too much risk of a Crispy Cruiser, Charcoal Customs-dude, or horror of horrors, the ac and
freezer crapping out at midnight in the tropics because the
batteries are flat. Oh, and toasted seagull is fishy and stringy....not like chicken at all. Needs a marinade first...
Weapons....there are ways and means to slay the wicked, or persuade them to behave, or to buzz off, other than the cartridge-fed kind. Bowfishing, anyone? Or, you can be like The Jackal and make your artillery look like something else, but watch out for
customs doggies, they'll find nitrates easy. Unless of course your projectile projector uses something else other than burning propellant to deliver the good news. If it goes hand to hand, better the blunt implements than the sharp ones, and keep in mind it may be below decks; so no two handed Conan swords, and if you're in the mood for
saloon kendo or baseball practice make sure you can swing your implement. Boarding pikes were popular in the old days too, and the Zulus had an interesting little spear for close quarters. Souvenir from
Africa, your honour. Any problem that can't be fixed with a hammer is probably an
electrical problem....so if it refuses to go away after a thorough application of hammer, give it a squirt of fire-extinguisher, or you may wish to squirt first and then hammer. If you have no hammer, use the extinguisher.. Mono-ammonium phosphate (wood, paper etc) or Bicarb of Soda (oil, fats etc) in those powder extinguishers makes a nice dense white cloud, stings in the eyes and other mucous membranes, and also screws up
electronics and fine machinery and takes three billion years to clean out of nooks and crannies, so weigh the risk. CO2 extinguishers might cool off an attacker, or at least a sixpack or three (heh heh), but using them below decks might sufficate you. NAF-III smells sweet and I think is not so good for eyes either, again, gassing yourself is not safe, but at least there isn't a white
christmas in the
saloon. Those good old yellow BCF 's, the same, though I'd save that for fires if the ecofascists haven't taken yours already. Pepper-spray etc....in a small space, you might get as much enjoyment out of that as your guest....but you have a gas mask handy too, seeing as how there are other ways of making a whole lot of smoke and unpleasant fumes; perhaps by
cooking for the visitor. Tasers can be useful for
washing.....throw the volunteer
laundry crew in the
dinghy with the socks and undies, add
water and tazer away. Don't forget to rinse after. Or, just set the Taserto medium-rare and let him know how you appreciate surprise company dropping in unannounced.
Bear in mind the saga is not over when the guests are gone....there may be explaining to do, or messes to be cleaned up. Or, a relocation before your hospitality makes the local rumourmill and you get more visitors looking for some interaction with foreign cultures.
Just use your imagination and common sense, be friendly, and clean up after yourself. Nothing to see here, just another boring poor cruiser on a shoestring
budget, minding his own business...with his eyes and ears open, and his mouth shut.