Sailing Visitors Blown Away By Help

[44'cruisingcat]

Originally Posted by CatNewBee

Well after all it floats - doesn't it? I am so sorry for them. Hope they can fix it soon and continue their journey.

Yep, must be terrible for them, being so badly damaged and it wasn't their fault.

I really hope they don't see this thread with some sicko gloating over their misfortune.

[JPA Cate]

In the thunderstorm that passed over Bundaberg Port Marina, I read that two catamarans were blown off the end tie, the upwind one sweeping the one in its lee off the dock as well. One of them scrunched into the stern of a mono, doing a lot of damage. I have not seen figures as to exactly what damage was done to any of the boats.

The news story is predominantly about how grateful the owners of Felix are for pretty wonderful community support, following the event.

***********

However, what I, as a monohullist am curious about, and could learn from was, were the dock lines too light or were the attachment points for the cleats not strong enough? or of a size to accommodate large enough diameter line? Was this a" silver line" failure
[silver line is made from recycled polyethylene, and is 3 strand twisted] or nylon? or something else? What size line were they using and of what material? It was only the cats that came agley. Their end tie position may have left them less protected, too. For me, this is not about slagging catamarans, but the attachments and line sizes also apply for monos--we have boats, and we tie them up, regardless of type.

Ann

[44'cruisingcat]

I heard that the upwind boat had it's headsail unfurl, which caused it to break free, running into Felix.

[arsenelupiga]

Originally Posted by catsketcher

It is interesting to calculate the effect of foam core on a submerged cat. Let's make a few assumptions. Foam weighs nothing. Distance from keel to gunwale - average 2.5m. LOA 12.0m, foam thickness 0.012m. Volume = 2.5x12x0.012 = 0.36 m^3. Multiply by 4 and we get 1.44 m^3. Add in a bit for a bridgedeck floor and you get some reasonable flotation, say enough to float 2 tonnes. For this boat we have 8 tonnes deficit so she sinks very low. I have only calculated flotation till the gunwale goes under but the cabin and interior should provide more flotation.

I don't want to come across as a Polyanna about this thread but cats that don't float well after catastrophic failure are pretty new to the cruising cat arena. The thought used to be that a cat with its bottom ripped out would usually float high enough to provide safety for the crew. So for some lighter, thicker core cats this is probably still the case. Hence why many cats don't have a liferaft, but it seems that the heavier cats don't provide enough flotation to keep the crew safe when the hull is ruptured. So a raft would be an important consideration for these cats. There have been more than a few racing cats that have had large holes made during racing that have gotten themselves home - XL2 once got T boned with a large hole, and they made it to a beach under their own steam.

I like learning more about the boats we sail but maybe there could be a private thread where we could discuss these things without causing owners of sisterships to feel annoyed.

cheers

Phil

this looks more like Lagoon 400.

Boat is allowed to weight up to 15 T .


You are forgetting fiberglass and balsa core that are used for lagoon. They displace water and although weight more than water and sink by itself, underwater weight less for the volume of water they displace. Same for anything else that is on board. 15 T boat stuff displaces say 10 T, therefore there is 5T deficit.

Front bows are watertight and each bow holds guestimate 3m3 of air. So this is 6T. Of course if not aftermarket installation compromised watertightness.

Then we have sacrificial keels that are filled with air and provide flotation. Say 500kg each, so you have extra 1 T, that does not help too much when inverted though.

And then you have watertanks, assuming half empty meaning they provide another 300 kg.

And then dinghy providing another 500 kg.

And then trapped air, more if one keep eye on how to make more air pockets.

So, I think there is enough flotation to keep fully loaded cat above water inverted or not even in fully loaded state.

Cat flip is deadly event, less than 50 % chance of survival regardless of the boat, so one should avoid it at all costs.

[Seaslug Caravan]

With the recently published pictures of catamarans sitting very low in the water it appears as though the days of not needing a life raft on a catamaran
are over.

Its interesting / sad that all the lessons learned from such catastophic events ,that are formalised to a degree in the yacht racing regulations are not taken into account when buying/owning a modern catamaran.

As cruisers we are happy to follow the racers and add square top mains, full length tracks, etc etc.in an attempt to improve performance, yet when it comes to the question of safety ,corners are cut.

For instance, how many have the facility to easily accomplish this..........

3.20.2 Multihulls shall have provision to pump out all watertight
compartments except those filled with impermeable
buoyancy.

or........

3.05.1 Adequate watertight bulkheads and compartments (which
may include permanently installed flotation material) in
each hull shall be provided to ensure that a multihull is
effectively unsinkable and capable of floating in a stable
position with at least half the length of one hull flooded.

From http://www.sailing.org.au/wp-content...-Keelboats.pdf

Anyone want to start a thread on marina mooring cleats, how to tie catamarans to said cleat, or "Character assessments of people who leave furled headsail aloft when not in attendance

"??

[smj]

Originally Posted by Seaslug Caravan

With the recently published pictures of catamarans sitting very low in the water it appears as though the days of not needing a life raft on a catamaran

are over.



Its interesting / sad that all the lessons learned from such catastophic events ,that are formalised to a degree in the yacht racing regulations are not taken into account when buying/owning a modern catamaran.



As cruisers we are happy to follow the racers and add square top mains, full length tracks, etc etc.in an attempt to improve performance, yet when it comes to the question of safety corners are cut.



For instance, how many have the facility to easily accomplish this..........



3.20.2 Multihulls shall have provision to pump out all watertight

compartments except those filled with impermeable

buoyancy.



or........



3.05.1 Adequate watertight bulkheads and compartments (which

may include permanently installed flotation material) in

each hull shall be provided to ensure that a multihull is

effectively unsinkable and capable of floating in a stable

position with at least half the length of one hull flooded.



From http://www.sailing.org.au/wp-content...-Keelboats.pdf

How about you post a picture of a holed cruising cat that is floating to your specs? I think that would be a positive contribution to this thread and possibly open up good debate on how to achieve better flotation.

[44'cruisingcat]

Originally Posted by arsenelupiga

Cat flip is deadly event, less than 50 % chance of survival regardless of the boat, so one should avoid it at all costs.

What an absolutely ridiculous statement!

By your statistics I'd be dead many times over! So would hundreds of Hobie, Maricat, Nacra etc etc etc etc etc sailors!

[smj]

How about this one? If I remember correctly it floated from the eastern Caribbean to Panama. Seems as if the majority of flooding is in the hulls making the bridgedeck livable.

[44'cruisingcat]

Plenty of cruisers sail boats that, if holed badly enough, will sink like a stone. Yet it doesn't seem to attract hundreds of stupid threads. Why?

[Seaslug Caravan]

Originally Posted by 44'cruisingcat

Yet it doesn't seem to attract hundreds of stupid threads. Why?

As the most PROLIFIC poster in most of these threads i was hoping you could answer that.

[smj]

Originally Posted by Seaslug Caravan

As the most PROLIFIC poster in most of these threads i was hoping you could answer that.

Come on slugster, show me some pics

[Paul L]

Felix is at least still floating. She was beached and at low tide, the hole was patched and the hull pumped out, then refloated. The forward watertight bulkheads kept her afloat. The starboard hull had an 18-24 inch gash just below the waterline midships caused by powering around the end of the dock that boat was pushed down on. The starboard hull flooded relatively quickly. Then water started to cross to the port hull through the cavity that has the steering gear.
It was very windy and visibility was near zero during the storm. We had 50-55kts sustained gusting to 67kts just down the dock. So what exactly happened is up to the insurance companies to work out. The other cat that came loose from the dock headsail unfurled after the bowsprit was broken on contact with the boat ahead of it.

[44'cruisingcat]

Originally Posted by Seaslug Caravan

As the most PROLIFIC poster in most of these threads i was hoping you could answer that.

Because you seem to focus your vendetta on catamarans.

[DumnMad]

Originally Posted by Seaslug Caravan

With the recently published pictures of catamarans sitting very low in the water it appears as though the days of not needing a life raft on a catamaran
are over.............

Cats are great for puddling around in shallow water full of coral bommies. They go where monos would never venture and with their vulnerable thin hulls its very sensible that they don't sink when the hull gets ripped. In these situations a dinghy on davits is more use than a life-raft. Liferafts are for offshore.
The Sail to Freedom Vlogger Plukkie was living on his half sunk boat in the Kimberlies while working out his next move.

[StuM]

Originally Posted by Seaslug Caravan

As cruisers we are happy to follow

We?