Leopard 46: Leopard 46 sinks after collision

[Richard5]

Originally Posted by chris smith

I am quite surprised that the Captain did not feel any impact when they hit ‘something’. If you ever hit the dock while docking at low speed, you feel the whole boat shake, I would expect an impact like this would throw one out of his bunk, or at least the helmsman would notice.

On a trip up the coast of California we hove to in violent weather. Sometime that night something metal, painted gray hit the bow and smashed down the stbd side. 3 planks were missing and the bow stove in. None of the 3 aboard felt a thing. No alcohol or drugs were involved. The damage wasn't even discovered for hours later when the fwd berth was found to be sopping wet.

[s/v Jedi]

Originally Posted by SVNeko

Man, I can just see the mess this would make in a saltwater environment after its adhesion breaks down and it starts to disintegrate into a powder.

yes LOL. I already gave up this discussion because expanding foam to fill voids around floors in houses has nothing to do with a sinking Leopard 46

[cwyckham]

Originally Posted by mcarling

No, but it could be used for adding buoyancy. Filling nooks and crannies with closed-cell spray foam will prevent water from entering those spaces.

Let's keep this to actual materials and techniques used by actual boat builders, shall we?

[Mr B]

Can any one on here tell me what the best material is to fill voids with on My Cat, Stuff that actually floats in water,

I had six supplied bilge pumps with mine, and a manual 1 and a 1/2 inch pump, Total waste of time,
If you have a hole in your boat, you need a very big pump to get the water out,

[David_Old_Jersey]

Originally Posted by SVNeko

Man, I can just see the mess this would make in a saltwater environment after its adhesion breaks down and it starts to disintegrate into a powder.

The cathedral hulled dories (popular in the 70's - pre RIBS) that were filled with foam discovered the joys of waterlogged and disintegrating foam - the only "cure" was complete removal.

[SVNeko]

Originally Posted by Mr B

Can any one on here tell me what the best material is to fill voids with on My Cat

I rely on empty jerry jugs.

[lhsmith]

Originally Posted by virgincapt

I was the delivery captain on this boat, and this is true. I had a quick glance underwater and saw the core, assumed foam, but maybe it was balsa.

Also, and very important, is that I never saw nor stated that the boat sank. Most likely she turned turtle and drifted back down wind to Roatan or other Honduran shore. When we abandoned her, she was heavily down by the stbd stern with both eng rooms flooded.

In all these cases of a breached, cored hull, if the production process does not include vacuum bagging, then the interstices of the core are open and so will allow water to travel throughout the core, thus seriously altering flotation qualities of the foam. Thus a cat can surely sink.

Thank you very much for your response. I salute your reported brave responses to the emergency, which undoubtedly saved the lives of the crew and set an example for us all.

If you have the time I have a few questions. Were you able initially to locate inside the starboard hull where water was getting in or were there multiple spots? What prompted you to go overboard to look for a breach? Did she list heavily to starboard first or just mainly sternward? Thus what was the main pathway of water into the port hull? Why do you think you did not hear/feel any impact?

Fair winds,
Larry Smith

[Andrew Troup]

Just a thought here: if you're planning to waterproof gaps around wiring conduits and such running into 'waterproof' compartments, you might want to reflect on the pressure they might be exposed to. There may be an appreciable static head, (even if the gap is under the deck, the vessel might be inverted, and the adjacent compartment virtually full) I'd be more inclined to think about the hydraulic shocks from sloshing, which can blow hoses off watertanks, even with the hoseclamps tight, if the connectors are smooth instead of barbed....

So as a minimum, I'd be cutting split flanges (from thinnish material) each with a semicircular cutout to go around the conduit, to be glued to the bulkhead on each side, helping to hold the sealant from being extruded by pressure spikes either way.

If the material was flexible and the conduit small, a single washer-like flange, with a single slit from outer to inner...

[Palarran]

Originally Posted by virgincapt

I was the delivery captain on this boat, and this is true. I had a quick glance underwater and saw the core, assumed foam, but maybe it was balsa.

Also, and very important, is that I never saw nor stated that the boat sank. Most likely she turned turtle and drifted back down wind to Roatan or other Honduran shore. When we abandoned her, she was heavily down by the stbd stern with both eng rooms flooded.

In all these cases of a breached, cored hull, if the production process does not include vacuum bagging, then the interstices of the core are open and so will allow water to travel throughout the core, thus seriously altering flotation qualities of the foam. Thus a cat can surely sink.

Virgincapt,
So the hull breach was midship and the water ingress flooded both engine compartments? Did the watertight bulkheads not work?

Could you find the source of the water inside? Like, you knew exactly where the hull was breached outside, what was on the opposite inside?

Would larger bilge pumps, or a crash pump such Jedi has have prevented the flooding?

Thanks for any additional info you can provide.