Warning some may find this disturbing

[cwjohm]

That's a long way different to saying their rigs are designed to act as fuses. I've never seen it discussed in any literature for these production cats, on their websites or handouts or heard it discussed at the boat shows by the manufacturers. Not mentioned in reviews.

Absolutely a long way. A fuse is a completely different beast altogether. I am not sure why you would bring this into the discussion.

By all means talk to the manufacturers at the Sydney Boat Show in regard to the issue of potential capsize. I certainly have and all of them are pretty happy to discuss. However, for obvious reasons it is certainly not something they would want to put in websites or handouts, nor would they under any circumstances want the marketing blowback of capsizing boats.

For a more comprehensive discussion however, you are probably better off talking to riggers who have a much better idea of the breaking strains of every aspect of the rigging. I, like anyone, who has attempted to push their boat to its limits, and paid the financial price as a result, have had many discussions with riggers in this regard and have identified several failure points that will go long before the boat capsizes. Certainly, I have discussed the possibilities of bullet proofing the rigging to overcome these failure points (and theoretically making the boat faster) but this seems pretty unsafe to me, not to mention costly.

[Mr B]

Keep in mind, This Cat was built as a Racing Cat to break records with.
Like all Major Racing boats,
They will have over powered sails, They are built for speed,
Too much power and you have a tendency to Pitch Pole,
Cruising Cats dont have the same sail area, So Pitch poling is near non existant on modern Cats,
If the new owners didnt reduce the sail area, Its still a Racing Yacht, CAT,

[mikereed100]

Originally Posted by Seaslug Caravan

Contrary to the "urban myths" peddled by the "multihull evangelists" catamarans require skill, forethought, concentration, experience and a little luck, to keep from capsizing.

I think that, while there is nothing wrong with all of the above, even more useful is a conservative mindset. Having switched to a cat after 30 years of owning mono's, I am convinced that my cat is a safer ride, providing I don't flip it. Keeping this in mind, we are deeply reefed whenever sailing in the lee of headlands or mountains and whenever in the vicinity of squalls. The incident described in this thread is an excellent example of why we do so. With the boat fully reefed our static stability is something like 65 knots and we really don't lose a lot of speed, even in light air. I don't think there's any reason a novice can't safely sail a cat, as long as they realize where the dangers lie and sail accordingly.

[valhalla360]

Originally Posted by Rustic Charm

To anyone else other than Trolls, I'll ask this question.

If a Vessel of this size, can flip in relatively smooth waters, in winds of say 40 knotts because the crew 'stuffed up', and had too much sail up, then would it not be fair to conclude, that such a boat is not a good option for inexperienced operators?

And secondly, as the article below claims and as many in the others in another CF thread have also claimed, big Cat's are designed to have their rigs give way before reaching a point of flipping. Is this correct?

Reasons to sail a Catamaran | Cruising World

Just like high performance mono's can be dangerous in the hands of an inexperienced crew, so can a high performance cat.

I've saw a demonstration video a while back where they tied off a cat and using a crane winched the boat over to 90 degrees. The mast didn't come off.

I suspect the "fuse" idea is an impractical one because it's too hard to dial it in just right so the rig isn't constantly falling down but does come down if the hull lifts.

[Factor]

Rigs are designed (well on most boats that I know of) to stay up - not fall down. It is impractical to think that built in rig failure would be a safety aspect, apart from the massive damage to the vessel, and consequential issues of a half attached rig, the real world reality is that very very very few boats capsize due to wind alone. I know of only two personally - one was a Lagoon 410, minding its own business until Hurricane Ike happened along and blew it over at its mooring. The other a racing cat. All other capsizes I know of involved pitchpoling rather than capsizing, wave action and vessel speed and placement were all contributory factors. I am unsure how you therefore design a rig to fall down before the boat capsizes in those circumstances.

In any event, a boat designed as a high speed high performance light weight flyer went over, its rig stayed intact and it was back floating in a matter of days - what is the big deal. The fact that it was advertised as a cruising boat doesn't make it so immediately, dont get me wrong, I would happily cruise on it, exactly my style of boat, but there are very many people who require airconditioning etc etc etc to be a crusing boat. Thus suggesting what BWR did given that it was advertised as a cruising boat some how has an application to other cruising boats is highly disingenuous.

The inversion, recovery and relaunch of BWR took less time than this thread has been running.

Dont sail them properly and cats can go over, park them at a mooring and the right wind can send them over, dont sail monos properly and they can sink or do a 360 degree spin etc etc.

How about we all settle down and accept the realities that seamanship must be in the seaman, not the boat. I get why Seaslug is concerned - he sails a boat that will in fact capsize at a whim. It is right that he is concerned given his knowledge is limited to an overgrown hobie. (great boat the Seawind 24 - just not a stable cruising platform). Those with more varied experience know that the sea demands respect still, but perhaps not the paranoia that un educated folk might have.

[44'cruisingcat]

Originally Posted by cwjohm

The wire size is irrelevant and is not the weakest point. You have the wire attachments to the tension adjusters. You have the attachment to the hulls, You have the attachment to the mast. You have the sails. You have the mainsheet. You have the blocks. You have the sheet locks. All of these can fail.

The reality is that there are many examples of rig failures in production cats as a result of too much sail in high winds. Sails blow out. Blocks blow out. Sheets strip. Mast attachments fail.

If you discard pitchpolling, then there are no examples that I have heard of flipping due to high winds alone in production cats (NB I do not regard a Chris White Atlantic as a production cat).

Actually, the wire IS the weakest point, in the standing rigging. All the rigging screws, swages, toggles and pins will be sized to match the wire.

Yes rigs have come down. Due to crevice corrosion, metal fatigue etc, the rigging can, over time, become much weaker than it was originally designed and built to be.

The first time I heard of rig failure being a "fuse" was in Gregor Tarjan's book. I asked Bob Oram about this, and he said it was simply impractical. Later conversations with other Cat designers confirmed this.

Momentary shock loadings can greatly exceed the amount that would lift a hull. If the wire was sized to break at this load, rigs would be falling down constantly.

[JPA Cate]

Originally Posted by StuM

But Evans suggestion doesn't involve sheet or boom release. If the "fuse" is at the clew/outhaul, all that will happen is that the foot of the main will blow out downwind.

Exactly, the "fuse" is at the clew to outhaul connection, and the material to be used was very light spectra line, and it was the number of turns which established when it would break. I don't remember the maths involved, but I'm pretty sure anyone could calculate a reasonable fuse, given the data, which they would have to dig out for themselves, or hire an engineer to do it for them.

Ann

[Seaslug Caravan]

Originally Posted by mikereed100

I am convinced that my cat is a safer ride, providing I don't flip it. Keeping this in mind, we are deeply reefed whenever sailing in the lee of headlands or mountains and whenever in the vicinity of squalls. The incident described in this thread is an excellent example of why we do so. With the boat fully reefed our static stability is something like 65 knots and we really don't lose a lot of speed, even in light air. I don't think there's any reason a novice can't safely sail a cat, as long as they realize where the dangers lie and sail accordingly.

Good points Mikereed100, but therein lies the crux of the matter.

Staying alert and making rational decisions, for the cold, wet, scared, seasick newbie, can be a real problem. Feeling confident , safe, and making the correct decisions regarding appropriate sail area comes with experience. Relying on instruments (such as the "scare-a-mometer") for a reefing cue can be a prescription for disaster. Only experience and feel will lead to one making the correct decisions more often. ( Some of the roll-cloud formations in the Gulf of Carpentaria give one little warning at night for instance., not to mention late season tropical sailing with thunder storm activity).

I must however disagree with you regarding...

" With the boat fully reefed our static stability is something like 65 knots and we really don't lose a lot of speed, even in light air."

Sail area is "king" when it comes to speed. Even trying to maintain way and drive to windward in waves requires a surprising amount of sail on a high windage cruising cat.

I suggest you do a little club racing and you will understand.

Now cranking up the motor is a whole different story, but that is not sailing.

[Factor]

Originally Posted by Seaslug Caravan

Sail area is "king" when it comes to speed. Even trying to maintain way and drive to windward in waves requires a surprising amount of sail on a high windage cruising cat.

I suggest you do a little club racing and you will understand.

I suggest you get more racing experience, reefing appropriately increases speed and VMG, it doesn't limit it. An overpowered multi will have depressed leeward hulls and increasing poor sail shape and be making more leeway, in racing it is critical to have just the correct sail area and no more, for speed and VMG, and in Cruising similar performance gains can apply with concomitant safety improvements.

I worry when I see ill-informned advice like yours, it may lead to some novice sailors failing to adhere to basic sensible multihull seamanship principles.

[Seaslug Caravan]

Originally Posted by Ann T. Cate

Exactly, the "fuse" is at the clew to outhaul connection, and the material to be used was very light spectra line, and it was the number of turns which established when it would break. I don't remember the maths involved, but I'm pretty sure anyone could calculate a reasonable fuse, given the data, which they would have to dig out for themselves, or hire an engineer to do it for them.

Ann

Anne, I keep responding to your fuse posts because you have a lot of offshore sailing experience on MONOHULLS so many newbies on her possibly put weight in your posts.

With your position comes a responsibility to not advocate half baked cheepo DANGEROUS fixes with no actual experience in the field of MULTIHULLS.

Have you actually thought through how you are going to impliment this "FIX"
at all reef points, to recognise the difference between shock loads and the difference in stability of a catamaran between fore/aft/ diagonal and lateral axis, and between light displacement with tanks empty, to fully loaded ( do some stability calcs, the righting moment can vary enormously),

Many smarter more experienced minds in the MULTIHULL field have discredited this idea.

A multihulls ability to sail up -right with lots of open space is condusive to the crew moving freely around the boat on most points of sail and not just cowering in one corner of the cockpit, which would make defending the unheralded fusing easier to defend on a monohull.

You may find EVANS was just pondering out aloud.
You may find he's left sleeping dogs lie , so to speach.

[cwjohm]

Actually, the wire IS the weakest point, in the standing rigging. All the rigging screws, swages, toggles and pins will be sized to match the wire.

Yes rigs have come down. Due to crevice corrosion, metal fatigue etc, the rigging can, over time, become much weaker than it was originally designed and built to be.

The first time I heard of rig failure being a "fuse" was in Gregor Tarjan's book. I asked Bob Oram about this, and he said it was simply impractical. Later conversations with other Cat designers confirmed this.

Momentary shock loadings can greatly exceed the amount that would lift a hull. If the wire was sized to break at this load, rigs would be falling down constantly.

We will have to agree to disagree. Several rigs that I know of have come down on newish production boats. Nothing to do with the rig and definitely due to operator error but nevertheless the rig came down before the boat capsized. Many more with blown out sails, stripped sheets, damaged blocks etc.

I can turn your logic around and state that if the rigs were designed such that something did not give way before capsize then we would have production boats capsized all over the place where literally hundreds of inexperienced sailors are buying them. It simply is not the case.

Yes, momentary shock loadings can greatly exceed the amount that would lift a hull, and in the case of a light boat like yours it may well flip - with a production boat - highly unlikely, as there will be a failure point somewhere else.

I believe that calling a rig failure a "fuse" confuses the matter. The reality is that in terms of overall specification production boats are not designed to create circumstances where a capsize is likely. You could argue that this is a side effect of cost minimisation in the production boats, but nevertheless the overall effect is the same.

It is a real issue that as you make the boat lighter and faster you take more risk in this regard. Whilst you may get a fast boat going at windspeed at 5kn whereas the production boat will not sail, commensurately a faster boat will require significantly more handling skills at higher wind speeds and if not carefully managed has the possibility of flipping. Clearly, this was the case with BWR.

[44'cruisingcat]

Originally Posted by cwjohm

I can turn your logic around and state that if the rigs were designed such that something did not give way before capsize then we would have production boats capsized all over the place where literally hundreds of inexperienced sailors are buying them. It simply is not the case.

Well no, because on most production boats the SA/Displacement ratio is so low it would take SERIOUS mismanagement for them to be in danger of capsize.

To put this in perspective, we once sailed past almost an entire fleet in a production boat "regatta" with TWO reefs in our mainsail, (we really didn't need even one reef, but we weren't going far and I was lazy) while they were all under full sail. Which would suggest our SA/D was greater with 2 reefs in than theirs was under full sail.


Anyway, it's easy enough. Check out the breaking strain of the rigging on a production boat and compare it to half the displacement.


We could lift our entire boat, fully loaded, on one stay. I doubt if that's exceptional.

[tp12]

Originally Posted by cwjohm

Absolutely a long way. A fuse is a completely different beast altogether. I am not sure why you would bring this into the discussion.
.

Umm, have you read the last two pages? Your comment straight after that looks in support of that design requirement. Apologies if it wasn't.

These boats do not have their rigs designed as a fuse. It's as simple as that.

[tp12]

Originally Posted by Factor

Dont sail them properly and cats can go over, park them at a mooring and the right wind can send them over, dont sail monos properly and they can sink or do a 360 degree spin etc etc.

How about we all settle down and accept the realities that seamanship must be in the seaman, not the boat. I get why Seaslug is concerned - he sails a boat that will in fact capsize at a whim. It is right that he is concerned given his knowledge is limited to an overgrown hobie. (great boat the Seawind 24 - just not a stable cruising platform). Those with more varied experience know that the sea demands respect still, but perhaps not the paranoia that un educated folk might have.

Amen. Thanks for that.

[cwjohm]

These boats do not have their rigs designed as a fuse. It's as simple as that.

Nobody made this claim.