500: Lagoon 500 Nearly Sunk

[dirkdig]

We had the wet exhaust hose come loose and pump some water into the bildge and the alarm went off quickly to alert us to water level increase.
I wonder if it was factory install alarm or fitted afterwards.

[DotDun]

Originally Posted by Palarran

I don't know about all Fountaine Pajot's but mine is the same. That is why in an earlier post I used a max depth of 2'. Above that and there will be a remake of "All is Lost". The max diameter of the holes put through my bulkhead was 2" not 4" so the total pressure would still be negligible. Also, as has been discussed, I have a water tight stern compartment, then the engine compartment, then the main cabin, then the forward v-compartment. If any single one flooded except the main cabin, it would make a very small difference in my buoyancy.

The reason I'm continuing to beat this dead horse is that this Lagoon isn't the only Cat lost due to water flowing from one compartment to another. I think it was a French guy with a newly purchased Lavezzi or Belize who had both hulls flood due to water crossing over through electrical raceways. I remember it because they had a good video of the rescue. If you own a cat, or any boat for that matter, you should pay attention to what's been drilled through your bulkheads.

I can attest that on the Belize model the FP factory did not drill holes through a bulkhead such that water can transfer from one compartment to another. Nor on the Belize model are there any electrical raceways within 24" of the waterline.

Flooding of any one compartment will not migrate to another, nor sink the boat. Flooding the largest of any compartment (the living space) will cause that hull to go down ~6 inches. (Don't ask me how I know this)

[Palarran]

Originally Posted by djtopper

I've been following this thread since it popped back up and must say it's chilling. I've also read tons about how unsinkable catamarans are by sheer virtue of the construction material. Makes sense, however, that a fully loaded cruising cat with all the comforts of home might in fact be way too heavy.

Makes me wonder, why don't they put some kind of water alarm in the engine bay? Seems like it would be a simple solution. EG., if the waterline goes above a certain mark, sound the alarm! Seems like it would be better than waiting until you notice one hull sagging.

Granted, it might have been useless in the case this thread is about. I honestly can't believe that an engine compartment isn't water tight though. I mean, it's where the boat quite literally transfers energy and force against the water.

It would be half as bad if the boats only sank when "pierced" as such. Having it happen as a result of the saildrive snapping seems like a dangerous design flaw.

I think many boats do have bilge alarms. I have them in both engine compartments. In both my main hulls there is a primary bilge pump, then an alarm, then a second bilge pump. The po used standard float switches for the alarms and they all tie in to one alarm panel.

Dot Dun, really, I have to ask how do you know

[Lagoon4us]

Ideally the bulkhead should have a valve at it's lowest point with a handle outside of the space so it can be opened and closed at will.

The spaces should each have a bilge pump with actuating alarm.

The valve can be opened if the one pump cant cope alone ie sharing tghe load by allowing the water to go elsewhere.

The power supply ie start battery can be isolated and you can use the opposite battery or house battery to keep the pumps going.

Meanwhile the source of water ingress should be dealt with.

Meanwhile a plan is formulated both for the boats safety and the crew.

Don't simply block holes up instead glass a socket and screw a valve into with an extended spindle, do this for the fire extinguishing hole as well OR have a bung tied beside it.....

[Palarran]

Latitude 38 - 'Lectronic Latitude

http://www.cruisersforum.com/forums/...ran-23009.html

[D&D]

Originally Posted by dirkdig

We had ...some water into the bildge and the alarm went off quickly to alert us to water level increase.
I wonder if it was factory install alarm or fitted afterwards.

Hi Peter

We have factory installed bilge alarms, one at the keels in each hull and next to the (both electric and manual) bilge pumps, with drains to take water from the fore and aft compartments down to the pumps.

PS Peter, check out (and enter!) our CF October Giveaway Thread at http://www.cruisersforum.com/forums/...ns-112457.html Who knows...might knock an extra $200 off those solar panels!

[dirkdig]

Will do

[djtopper]

Originally Posted by Palarran

Latitude 38 - 'Lectronic Latitude

http://www.cruisersforum.com/forums/...ran-23009.html

That's an interesting story. It's also yet another example of how your saildrive can get snapped off and cause serious problems. The pics seem to defy logic in terms of that FPs positive buoyancy. But I can also see where that older gen FP and the newer, larger, and much heavier L500 would be light years apart in that respect.

The thing is, the L500 is one of my favorite boats right now. I feel it represents one of the best values in terms of price and size. I'm looking forward to chartering a few next year. I hate the fact that there are potential hazards like this lurking about. I guess it would be something to check for before heading out (ie., has anything been drilled through the bulkheads from the engine bay).

Regardless, the story seriously calls into question which cats will remain afloat and which ones will not. Guess I'll have to keep putting stacks of $100 bills in the piggy bank as I save for 5X or a Gunboat. ;-)

[Therapy]

Originally Posted by djtopper

Regardless, the story seriously calls into question which cats will remain afloat and which ones will not.
;-)

My guess is that after loading for a "trip" the answer is; NONE.

[jeremiason]

Just out of curiosity... Where are you getting this information? I don't see any news on the Internet.

[Palarran]

Originally Posted by djtopper

The thing is, the L500 is one of my favorite boats right now. I feel it represents one of the best values in terms of price and size. I'm looking forward to chartering a few next year. I hate the fact that there are potential hazards like this lurking about. I guess it would be something to check for before heading out (ie., has anything been drilled through the bulkheads from the engine bay).

There are hundreds of them. That's the problem with reading this forum. It can freak you out with all the "what if's" and "should have's".

The positive is that you do develop a sense of what to look for. I really don't think sailing/boating/cruising is an innate skill.

[Captain Bill]

Originally Posted by minaret

Read it again, both hulls were lying on the bottom. And they specifically state repeatedly that there was no reserve buoyancy left above the point to which she filled, only rigging. This boat sank. The skipper who brought the boat out from France, and who salvaged her, stated repeatedly that the boat would have sunk to the bottom if it hadn't been beached.

Ok I read it again. The guys that refloated her said the keel on the compromised hull sank into the mud after the tide went out and there was not enough buoyancy to unstick it until they closed the hole in the hull and pumped her out. I've lost shoes to deep mud myself and know that the effort required to unstick something from it can be tremendous. The water rose to the roof because the hull was being held down by the mud. I would doubt any cat has enough reserve buoyancy to unstick itself from soft mud when the hull is full of water. I stand by my previous statement that we do not know from this example if a lagoon 50 would stay on the surface awash or sink to the bottom.

[minaret]

Originally Posted by Captain Bill

Ok I read it again. The guys that refloated her said the keel on the compromised hull sank into the mud after the tide went out and there was not enough buoyancy to unstick it until they closed the hole in the hull and pumped her out. I've lost shoes to deep mud myself and know that the effort required to unstick something from it can be tremendous. The water rose to the roof because the hull was being held down by the mud. I would doubt any cat has enough reserve buoyancy to unstick itself from soft mud when the hull is full of water. I stand by my previous statement that we do not know from this example if a lagoon 50 would stay on the surface awash or sink to the bottom.

The skipper of the boat, who knew it well and was actually there, doesn't seem to agree with you.

[Sand crab]

Originally Posted by minaret

The skipper of the boat, who knew it well and was actually there, doesn't seem to agree with you.

Minaret, I love ya man but Is this the same skipper who ran over the dinghy painter several times before finally getting it "right"

[Captain Bill]

Originally Posted by minaret

The skipper of the boat, who knew it well and was actually there, doesn't seem to agree with you.

The skipper was not testing the boat to see if it would float full of water he was saving his butt and rightly so. He did the right thing by beaching it and getting himself and his crew off safely. The boat never even got close to "sinking" before he beached it. If it had he would have had no way to get it to the beach. Just because he can captain a boat does not mean he knows how much reserve buoyancy it has. If you remember, the captain of the Titanic thought his boat was unsinkable. Given the credence you give to the captain's untested opinion surely the Titanic must floating around somewhere. The FACT is that this instance does not tell us one way or the other if the Lagoon has enough reserve buoyancy to stay on the surface when fully flooded or not. I seriously doubt that any owner is going to go out in the ocean and swamp his 50 ft cat to find out either. The Captain's opinion is just an untested supposition which may be right or may be wrong, but we'll never know from this incident.