Sinking ??????

[Lagoon4us]

So often sinkings, explosions and fires and such occur soon after SOMETHING has just been installed, quite often the installer has no experience and/or no consideration for systems marine.

I have seen cable trays secured against a 40mm GRP hull in a forepeak using 50mm PK's.....

The saddest was a Prop stuffing gland secured by single hose clamps at each end, the torque alone would have tested them.. The heat initially generated enough to embed them into the synthetic hose that was used...

As i said before many times suspect the most recent work done, as Dan say's it ain't rocket science.

Cheers

[Lagoon4us]

I'll share another form of sinking with you, it's called 'Sinking by Desperation' it happens now and then and usually/initially is inexplicable to the general public.

As an accredited ship builder i was involved with most marine insurance companies in Australia, this is a true story however it is 20 years old and i'll change names and places.

Two guys were in their dinghy fishing, both had shared a carton of tinnies (24 beers) and were having a great afternoon. They noticed a fellow in a tender go out to an anchored 70 foot charter motorboat nearby and very hurriedly leave 20 minutes later.

Another 30 minutes expired when the Charter boat exploded, the explosion so violent the bottom of the boat embedded it self in the Harbour mud 10 feet below, the top half/deck and cabins went airborne some 60 or 70 feet. Debris rained down for an eternity..

Within a half hour the water police were out asking all in the area for info, these guys were half cut and concerned with being charged however the moment sobered them somewhat and they gave police the info needed, they couldn't testify because they were drunk.

The 'sinking' was by way of a candle in the engine room set 3 or so feet up from the top of bilge, an LP Gas bottle was set in the bilge and opened with candle lit.

In demolition the air/gas mixture is crucial and this guy 'got it right' too high and it's a burn ie too rich, too low and it fizzes BUT at correct ratio it is a huge bang.

How do i know, the insurance company paid out and just waited, human nature dictates all criminals such as this usually just have to tell their mates how smart they were and this is what occurred, a year later he was in court all funds were seized and he paid for his stupidity by a record for fraud and a jail term.

Sometimes sinkings are a result of desperation.......The boat suffers, it was a twin engine reef charter boat quite famous on the coast, enjoyed by many........

Frank

[micah719]

So, that would fit in the 4% "other" reasons in Cap'n May's post. Was wondering about those...

I read a story once about a GRP boat sinking because someone left a bottle of nail-varnish remover (acetone) open in the heads compartment: it tipped over, leaked into the bildge, ate a hole in the hull and sank it. I'm fairly sure it was in a book by Peter Kemp.

Must remember to be careful with my nail-varnish remover. And no lpg-sniffing sessions by candlelight in the engineroom.

[CnC40sailor]

Man, I really love my diesel, even if that gas was setup. Really makes me greatful, at least I know one way my boat won't sink....

[Lagoon4us]

Originally Posted by micah719

So, that would fit in the 4% "other" reasons in Cap'n May's post. Was wondering about those...

I read a story once about a GRP boat sinking because someone left a bottle of nail-varnish remover (acetone) open in the heads compartment: it tipped over, leaked into the bildge, ate a hole in the hull and sank it. I'm fairly sure it was in a book by Peter Kemp.

Must remember to be careful with my nail-varnish remover. And no lpg-sniffing sessions by candlelight in the engineroom.

A mere bottle of acetone wouldn't do that... A marine myth?

[Lagoon4us]

Originally Posted by CnC40sailor

Man, I really love my diesel, even if that gas was setup. Really makes me greatful, at least I know one way my boat won't sink....

Agree there BUT the most destructive is a secondary explosion to further burn the airborne dust/particles it is much more destructive, BUT you will always be caught.... It's beens 'so done before' and the least charge is fraud if no one gets hurt. Many boats have gone this way, i know of 3 and i come from a small populace....

[belizesailor]

Originally Posted by foolishsailor

I love it when Gord brings facts to the discussion that match my own anecdotal experience. Makes me feel smart

...

Yes, the Boat US stats match what I have seen as well. Most boats sink in the slip.

I was approaching a transient slip once, and something just did not look right. I went forward on the bow to have a better look...lying on the bottom in the slip was another boat! And, the dock master had directed me to this slip -- apparently they didn't pay much attention to what went on in their marina.

[micah719]

A mere bottle of acetone wouldn't do that... A marine myth?

Myth? Perhaps...I'll dig in my cellar one of these days, I'm certain I have the book I'm thinking it was in. From what I remember he had it hearsay as well. If it ran into the bilge I can only imagine a nasty mess, but if it dripped continuously on the one spot I assume it could eat a hole. Maybe something to experiment with to see if it works. Mythbusters?

[Cheechako]

Unfortunately Gord's results appear to include your average water skier.... probably way off for sailing cruisers..
"Drain Plug Missing: 12%
Navigation Error (Grounding): 10%
Boat Construction (Hull Split Open): 6%
Leaks at Outdrive Boots: 4%"

hmm.... how does your drain plug end up missing in "open water" ...?

[Mr B]

Drain plug missing at the end of the ramp, Just after launching your speedboat,

How many have sunk that way,

[Cheechako]

I dont know about sunk.... but very wet inside!... quite often I think... last minute rush at the launch ramp etc...

[Mark Johnson]

Originally Posted by CnC40sailor

I know I'm going to be chastised for this, but how on earth do boats get to the point of sinking? If you have hoses properly fitted and replaced when needed, seacocks in working order, and other simple maintenance things, how the heck does it happen (don't tell me you hit an iceberg)?

I have worked on HUNDREDS of boats for 43 years, and other than my own, which I built, never seen such a "safe" boat. ALL production boats, even high end ones like Caliber & Pacific Seacraft, use cheap hose clamps, rather than all 316SS AWABs. It baffles me. What are they thinking?

They regularly put mediocre hoses where you can't even get close enough to the end to see them directly, much less a close inspection. You can't tell much in looking for micro cracks, from 3' away, with a swivel mirror.

Production boats are built down to a price, and NO regard is given to the guy like me, who later works on them.

PS boats, for example, mount the head to the pan before mounting the pan into the boat. You can't replace the head, because the nuts underneath are not captive. You have to drill a large inspection plate sized hole, just to hold the mounting nuts from spinning!!!

It just goes on and on. Every single piece in most production boats is put in there in a way that saves the builder money, and simplifies construction. To hell with ownership later.

FAR less than 1% of all boats built, ever go out of sight of land, so they assume that to be the case.

High end boats go out of business first, more often than not. People want quality, but won't pay for it. It is usually the "pretty good, but for a REALLY good price" boat companies, that survive for decades.

If I ever switch from my self built (litterally unsinkable) trimaran, to a production monohull, I would re-wire and re-plumb it from stem to stern. Then I would rely on just ONE good seacock and a manifold to supply the other needs.

Then I would watch everything like a hawk!

I find leaks & "sinkings about to happen", all of the time...

[belizesailor]

Originally Posted by Lagoon4us

I'll share another form of sinking with you, it's called 'Sinking by Desperation' it happens now and then and usually/initially is inexplicable to the general public....

Had a similar, but not quite so dramatic experience. Used to work for a small charter company. One of their boat owners was a naive new boat owner and her dream of owning a boat was quickly turning into a nightmare. So she enlisted her not too bright boyfriend to solve the problem. We noticed him on the boat briefly one afternoon and then later noticed the boat listing a bit. Went below to discover a very obviously cut hose below the water line.

We pumped her out, repaired the hose, sent the owner a bill. And, advised her that this was a really bad idea.

[rtbates]

1. You forget to close the head seacock
2. The intake anti siphon valve was clogged.
3. Head is the 'normal' kind; ie NOT VACUUM type like the LAVAC...

Fortunately for us we DO have a LAVAC

The LAVAC's vacuum seal stopped the water ingress when it met the lid seal

When my wife opened the lid water went everywhere.

I OWE MY BOAT NOT SINKING TO OUR LAVAC HEAD and LUCK...

[rgscpat]

1. Poor maintenance, lack of inspection, bad design and/or manufacture contribute to leak in boat in marina slip.

2. Owner relies on electric bilge pump to "solve" the problem -- perhaps not even realizing how serious the leak is, or the leak eventually becomes worse -- perhaps suddenly, and perhaps when the owner is absent for a prolonged period.

3. The bilge pump fails after a long period of over-use, or the power goes off for an extended period (during a storm, because of an electrical short, whatever).

Bye-bye boat.