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Old 21-08-2010, 07:57   #256
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Originally Posted by MarkJ View Post
You two youngsters just don't listen to moi!

I suggested putting it to a product engineer.
We thought you were too busy drink good red wine and thinking about playing with velvet

The french (open 60's and g class multis) have looked at this problem (actually a slightly different problem . . . their focus is preventing the loads from breaking the boat, not preventing capsize) and concluded fuses were the answer. That does not mean they are right . . . perhaps their engineers are also distracted by red wine and velvet

I don't understand the reluctance to a clew fuse:

1. I am sure in cruising mode you don't want/plan to ever fly a hull, and lets say 5 degrees of flying hull is the most acceptable. If you set the fuse at the 15 degree righting moment you have a 3x safety factor (the righting loads are almost linear at that part of the curve) so, it will 'never' blow in normal conditions but could save you from a capsize.

2. If the fuse breaks, the clew is going to go up (due to leach loads), and the clew/boom is already high on these boats, so the sail is going to pose no safety issue. The boom is going to recoil when the load is let off (as Joli said). I don't have any sense how much/how hard with a low stretch sheet. But it is pretty high and out of the way on these cats (especially the Atlantic's) and you could trap it with a normal preventer. All in all, it does not sound like a serious problem, especially given it will only happen just before capsize.

3. The fuses are cheap and easy to make and cheap and easy to replace. It's just a spectra lashing. We could all make one up next week, without engaging harken to do 5 years of product development. You could call up one of several french riggers who do this and ask them to make it happen, or as any good cruiser would, do it yourself . . . You need the 15 degree load, and the actual breaking strength of some spectra rope. The NA should have the expected 15 degree load, or if not, someone like North sails or Harken could make an excellent estimate. Or you could buy/rent an inexpensive load cell and just go measure them yourself, or do a standard incline test. All of which would give you enough data to size the fuse - remember you have a 3x factor so this does not need to be super precise. Then you call up New england ropes or Samson or Yale and tell them what you want to do and ask if they will make and break some lashings for you to proof test the right number of turns on the lashing (or just go with the rated loads).

4. I personally think the 'automatic' feature of the fuse is better than the 'manual release' approach Mark and others are proposing. First, from a mechanical reliability perspective, the fuse has no moving parts and will certainly still work after several years of not being used (in fact it will work 'better and better' over time due to chafe and uv), while the manual releases are all vulnerable to freezing after not being used for several years. Second, I am looking precisely for something that will work when I am distracted or not paying attention or out of commission for some reason. The manual release does not seem to fit that basic criteria.

Honestly the fuse seems like a 'no brainer' to me. . . . no downside and the possibility it might save a capsize.

The weather awareness/reefing approach to preventing capsize is obviously best. But it's also obviously a delicate balance, much much more than on a mono.

First you have just spent a whole pile of money on this performance machine. Even if you know you 'should', how likely are you to want to 'cripple' it by sailing around with a reef whenever there is a cloud in the sky. This is easy to dismiss sitting ashore, of course we all say, we will do whatever is proper seamanship. But then you are there on passage, in 10kts of breeze, with a few squalls around and you realize you could get in a whole day sooner if you put the full hoist up. You 'know' the boat is very stable and safe, if you can get a little more boat speed you can probably sail around the squalls. Are you going to sit there with a reef in?

Second, as Kettlewell says, the wind/weather is really unpredictable. You can sail around a corner in 20kts and then be surprised by 50kts. You can get a 60kt 'dry microburst' out of an almost cloudless sky. You can be sailing thru a whole series of squalls that all look the same and all have only 20-25kts except the one with 50kts. Very often the gribs (and every other forecast) are just plain wrong. So, sometimes we are just very surprised.

Third, fatigue and distraction are deeply integral to double handed passage making. I at least find it impossible to be 100% alert, and 100% efficient, and 100% making good decisions. I try to save up energy in the 'safe times' so I can be more alert in the unsettled times. But see point #2, sometimes I am simply taken by surprise when I am not alert or thinking clearly. It may simply be that these performance cats should have three or four on board for passagemaking . . . but for us that's not 'cruising' as we know it.
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Old 21-08-2010, 08:39   #257
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First you have just spent a whole pile of money on this performance machine. Even if you know you 'should', how likely are you to want to 'cripple' it by sailing around with a reef
I had a disturbing couple of weeks about a decade ago when I was crewing a guys monohull.
Not only did he refuse to reef but he refused to let the sails out at all when off the wind.

He had sails hard in tight close hauled when on a beam reach. Always.

The reefing actually didn't work in that it was in boom hydraulic system that had no break effective so if you rolled down to the first reefing point it would just unroll itself.

This guy did not have much experience but had taken a yacht club commodore out on a 500 miler and the saying that came back from that was: "Frank, you just can't do that!" (I've changed his name).
But Frank just did as he wanted.
Funnily enough the boat went reasonably well on a beam reach with sails closehaulled. I dont think we ever went deep downwind.
He did tell me on a couple of occasions to "make the boat sit flat" so he and his girlfriend could have lunch.

Some people who are self made men of wealth have made themselves through all sorts of adversity. They don't want to be told 'you just can't do that' either by man or by the elements, physics or god.




Needless to say god must have spoken to me and I decamped at the next port.

Mark
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Old 21-08-2010, 10:08   #258
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Going a little off topic. I sailed with a guy not frank but a close relative. About 3 days out were caught in a blow and as I'm leaning hard down on the wheel in the gusts he tells me he fused the steering gear because the chain kept breaking. Close relative if frank caused me hours if anxiety as we surfed down the side of the rollers. I don't want to cruise with someting that's designed to break ever again. I m getting lower tech by the year.
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Old 22-08-2010, 21:11   #259
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Thanks for posting the link to the rescue Tao. It's the best one i've seen yet. I'm amazed by how high ANNA was sitting in the water. The escape hatch is well above water level.

I think it was interesting for me to view her bottom side as my assumption was that cat's with daggerboards don't have keels, and yet they do.
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Old 22-08-2010, 21:37   #260
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. I'm amazed by how high ANNA was sitting in the water. The escape hatch is well above water level.

Hi Palarran,

I've looked and looked at that photo posted by Tao and I cannot see the escape hatch. I probably need glasses as I am probably just having a "man look" and it will probably jump out at me when you point me in the right direction as to what part of that photo of the upturned Anna it can be seen in.

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Old 23-08-2010, 03:14   #261
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Designer speaks.

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Old 23-08-2010, 05:17   #262
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The reason this Cat flipped is because the LEE daggerboard was deployed.

As the Windward hull lifts a board deployed on that side allows the boat to slide and slew around the rudders so turning mainly downwind, the recommended tip avoidance manouvre.
It wasn't a bad design, an over complex boat or anything else, just that the WRONG DAGGERBOARD WAS DEPLOYED.

I think I saw early in this thread that the boards were asymmetric section, ie designed to lift more one way than the other. Had they been fitted to the right side? Did this crew fit them? What is the designers view on this.

And take note, you dagger cat men, an UPWIND DAGGERBOARD IS SAFE.
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Old 23-08-2010, 05:21   #263
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I think there is a certain point in every disaster where someone somewhere thinks to themselves.....

This just doesn't quite feel right......

Its kinna like a radar built in! I have friends without this feeling and they are the ones that are continuously breaking and hurting themselves.

I think if you get that feeling it's time to do something....if not just before you get that feeling is also a good time to do something!
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Old 23-08-2010, 05:43   #264
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Ozbullwinkle, watch the video. It's the black square right next to the guy on the dingy. There would be another one on the other side, which you can't see.
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Old 23-08-2010, 08:27   #265
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Quote:
Originally Posted by Palarran View Post
Thanks for posting the link to the rescue Tao. It's the best one i've seen yet. I'm amazed by how high ANNA was sitting in the water. The escape hatch is well above water level.

I think it was interesting for me to view her bottom side as my assumption was that cat's with daggerboards don't have keels, and yet they do.
Some do, some don't. It varies according to the designer and the design goals. For example, our Maine Cat 41 has daggerboards, but no keel. The smaller Maine Cat 30 has two keels and a single daggerboard.

Fair Winds,
Mike
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Old 23-08-2010, 09:20   #266
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I found two things interesting:

"And they (anna) had the same sail up as Javelin did in the squall I just mentioned, a single reefed main and the full self tacking jib."

I had not realized that they had capsized with one reef already in the mainsail! I went back and reread the log and that is correct. Some of the thread discussion has suggested/implied they had a fully hoist main. That makes this case even more worrisome.

"If the boat is sailing against the wind (true wind forward of the beam) and a dangerous gust occurs it is normal practice to turn into the wind enough to de-power the sails. If the cat is sailing down wind (true wind aft of the beam) normal practice is to alter course away from the wind."

Chris seems to place equal emphasis on turning up (when the wind is forward) to spill sail loads rather than always turning down (to lose apparent wind) as many have suggested in this thread.

One question for you large multi-hull sailors - can you reef while sailing downwind? If you get into a squall and turn down and are running in 40kts and it continues to build can you then drop in a reef or do you have to turn up to do that? In most (largish) monos the mainsail will hang on the lazyjacks and spreaders and rigging and you simply can't drag it down to reef in over about 30kts true, but a multi rig will have somewhat less stuff (although I presume the same lazy jack stuff) for the sail to hang on.
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Old 23-08-2010, 10:06   #267
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Some do, some don't. It varies according to the designer and the design goals. For example, our Maine Cat 41 has daggerboards, but no keel. The smaller Maine Cat 30 has two keels and a single daggerboard.

Fair Winds,
Mike
My Malcolm Tennant Timeliner 47 has twin daggerboards AND minikeels. The minikeels also help when beaching to protect the saildrives & rudders. I would also like to see more opinions on whether the lee or windward board should be down when close reaching in strong winds (25 kts apparent and above). I have heard arguments for both sides. I usually put the weather board down, but that's just my 2c FWIW
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Old 23-08-2010, 10:49   #268
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I would also like to see more opinions on whether the lee or windward board should be down when close reaching in strong winds (25 kts apparent and above).
Perhaps mostly a racer vs cruiser split.

The racers use the lee board because they plan to fly the windward hull and so its board will not do much good, and in any case the lee board will be submerged deepest and so produce the most lift.

Cruisers might use the windward board because they do NOT plan to fly a hull, and if they do get a hull flying they want the boat to sideslip as a safety factor.
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Old 23-08-2010, 10:58   #269
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Actually, Estarzinger, there have been many posts on the this cite where it is made clear that with true wind forward of the beam, it is best to head up, rather than off, as:

1. your sails will quickly luff and depower, whereas by heading off from a beat/close reach, the sails keep pulling and there is, in fact, an increase in the side (heeling) vector to the force from the sails (typically about 10 - 15 degrees forward of a right angle from the boom/foot of the sail).
2. It is easier to reef when headed up into the wind (although with batcars and a downhaul, most cats can be reefed downwind).
3. If the seas are following the general wind direction, you risk turning the side of the boat into the seas and thereby increasing the risk of capsize.

Those who suggest that you should always head off when overpowered in a cat are not only in the minority, they are wrong for all of the above reasons. Yes, a turn to windward does increase the centrifugal force to leeward and the apparent wind; however, only a very sudden/sharp turn would cause any significant centrifugal force and by then the sails would already be depowered, and the waves hitting the boat at a less harmful angle.

When on a broad reach/run and overpowered, turning off the wind is the preferred course of action as it again keeps the side of the boat out of the waves, reduces the apparent wind and, in conjunction with a slackening of the sheets, moves the force vector from the sails forward rather than to the side.

Agreed, the boat clearly had a single reef in the main - although the size of that reef is unclear. Some first reefs are only 10 per cent of the whole; even at 20 per cent, it is clearly not enough for that boat with unsettled conditions and approaching squalls. Even still, if as soon as they felt overpowered they had headed up, luffing the sails, then let out the sheets, started the diesels to keep her into the wind and reefed, we wouldn't have been reading about this.

Relying upon an autopilot while staying below with that much sail up and unsettled (at best) conditions is and was a recipe for disaster.

Brad
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Old 23-08-2010, 12:31   #270
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I am a bit confused about what you would have done.

Their log says: "suddenly we were on a beam reach"

and you say : "When on a broad reach/run and overpowered, turning off the wind is the preferred course of action"

So, I guess here you are agreeing with the thread recommendation to turn down, rather than with their attempt to turn up.

but in your last post you seem to be saying they should have turned up: "if as soon as they felt overpowered they had headed up . . . . we wouldn't have been reading about this."

Which do you in fact think they should have done, turn up or down?

"Some first reefs are only 10 per cent of the whole; even at 20 per cent, it is clearly not enough for that boat with unsettled conditions and approaching squalls."

It actually looks like a quite deep 1st reef - see attached photo - I have added red line where 1st reef is - I am guessing that's a 15% of hoist (25% of area) reef. I guess you multi-hull guys already knew all this, but I find that even more eye opening - wind capsize with 25% of the mainsail down! The balance here is even more delicate than I had guessed. This thread is doing a great job recalibrating my whole sense of the trade-offs with these machines.

"Relying upon an autopilot while staying below with that much sail up and unsettled (at best) conditions is and was a recipe for disaster."

Hmmm . . . perhaps this would be something we would have to change if we go multi-hull, but we essentially never steer when on passage. We have enough going in sail handling in squalls with just the two of us to be pleased to let the autopilot handle the steering. And quite honestly in squalls at night (which the Anna incident was not) I am more likely to get confused and disoriented (and jibe or tack accidentally) than the autopilot.

It would take no time ,if the autopilot was set to steering wind angle (which ours usually is), to punch it either up to just above close hauled or down to a very deep reach (but not so far to risk a jybe) and then go back to sail handling. With the Atlantic cockpit layout I would think that would be faster than getting to the wheel. As a mono guy that would be my reflex action. Perhaps I would have to relearn/retrain that reflex, and take a multihull wheel more, but then I am stuck on the wheel and Beth is alone to do all the sail handling. Somehow that does not seem like the right answer when we have a very capable autopilot.

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