How many cats have flipped ?

[KP44]

Originally Posted by smj

Ramtha’s crew got pulled of the cat by a ship and survived to sail Ramtha again.

Thank you for that update. That is good to hear.
The scuttlebutt here was that the crew abandoned ship and they were lost. It's good to know the truth.

[boatman61]

Left to their own devices most boats will survive.. its the crew that usually kills them..

[44'cruisingcat]

Originally Posted by KP44

I remember the 40' Cat, RAMTHA, in the Queen's Birthday Storm. Several boats had problems. And it appears the Catamaran's crew abandoned ship. Ramtha was found intact after the storm but the life-raft and crew were never found.
Even without a crew to guide her, the Cat came through the storm.

The post above yours has a link to the story.

Both "Ramtha'"s and "Heart Light"'s crew were rescued. Also the crews of the mono's who issued maydays, bar one, which was lost.

Heart Light would almost certainly have made it through as well, since the storm was reportedly abating when the crew was taken off, but the female crew member insisted that the rescuing ship ram and sink their boat as some kind of offering to the sea.....

[BigBeakie]

Bullshooter,

That refers to how you can leave your sheets or mainsheet on a self tailing winch, and yet be able to disengage the sheet quickly by just pulling it. Instead of leaving the tail of the sheet wrapped through the self tailer in a clockwise direct ( the same way it went on), you reverse the direction of the sheet tail, ie counterclockwise, but leave it engaged in the winch self tailer. You can take the sheet tail to wherever you are for quick access.

Then if you need to let the sheet fly in a hurry, you just pull the sheet, it pops out of the self tailer, and the sheet should then run free if you haven't put too many wraps on the winch drum.

Make sense? You might be sitting at the cockpit table having lunch and if you get hit with a big gust, you can release the mainsail sheet to depower the boat in a hurry. Seconds count !


Sent from my iPad using Cruisers Sailing Forum

[Bigmarv]

Originally Posted by Dockhead

That's the thing about easily driven hulls (cat or mono, but much easier to achieve on a cat). A tubby boat needs a lot of sail area to get it moving, so then you're dealing with that lot of sail area when things get lively. Is that "safe"? Not in my book. I always admired that about Dashew's Sundeers with the very modest rigs but such a low D/L (under 100, similar to a performance cat's), that they could sail in almost any wind, yet never be a handful in strong conditions. As an additional bonus, the low windage from the modest rig improves the ability upwind.

I know you like the Dashew boats but I'm yet to see one sail impressively upwind or in light winds, or to talk in person to somebody who has. The design compromises that sacrifice upwind and light wind sailing are obvious, and there to read in the Dashews' books if you look past the salesmanship.

Agreed on the value of easily driven boats, and the Dashew boats went easily and well reaching and off the wind, but they motored in the light and motored up wind. A very American idea of a good sailing boat.

[Dockhead]

Originally Posted by Bigmarv

I know you like the Dashew boats but I'm yet to see one sail impressively upwind or in light winds, or to talk in person to somebody who has. The design compromises that sacrifice upwind and light wind sailing are obvious, and there to read in the Dashews' books if you look past the salesmanship.

Agreed on the value of easily driven boats, and the Dashew boats went easily and well reaching and off the wind, but they motored in the light and motored up wind. A very American idea of a good sailing boat.

Well, but that's the way 90% of catamarans are used, also, isn't it? Easily driven also makes a superlative motor boat, and it's much less trouble to light up the Yanmar than it is to get a non-white sail up.


I have seen Dashew boats sailing superbly well in light wind, but -- using non-white sails. Just like the performance cats I know. Short handed crews of both types of vessels usually use the motor instead, and I don't think there's anything particularly "American" about it.




The Dashew boats are somewhat limited upwind most of all by their shallow and non-bulb keels, I think, something I would not like. On a mono, there is no substitute for draft for getting upwind. But AFAIK the Dashew boats are not actually too shabby upwind despite that -- the key being the lightness, long waterline and speed potential, which cuts down leeway and allows you to achieve high VMG to windward despite modest AWA angles. The same principle by which some even non-performance cats without boards do surprisingly well upwind, contrary to the prejudices of many mono sailors.



But again, the crew has to be willing to be bothered. Cat or Sundeer, most crews choose to motor upwind rather than tack if the sea state is reasonable.


I've been doing it myself lately, despite my carbon sails and great efforts to make my boat sail well upwind. Last big trip I did was last month, from Cowes to Helsinki in 9 days with only 3 stops. We averaged about 150 miles a day including the stops. I was in the middle of stuff with work and was not able to take time off to do this trip slowly. Unfortunately in May the prevailing SW winds are frequently reversed to NE, and we had to make a lot of miles directly upwind. As long as the sea is not up so much that the head seas are stopping you, you can just hand over to Mr. Yanmar and let him deal with it, and go directly against the wind if you want, saving vast amounts of time either tacking or waiting for a wind shift. Motoring against 15-20 knots of true wind but with seas not too steep I can generally make about 7 to 7.5 knots using about 2500-2600 RPM. It burns some fuel -- maybe a liter per mile -- but there is no way to come anywhere close to that speed in VMG made good to windward by tacking. Of course that all changes with a little more wind and/or a little steeper seas.



This is different from open ocean sailing where you can do tactics and head off waiting for a wind shift and play the wind shifts -- this was 1300 miles with routing constraints including TSS's, wind farms, coasts, etc. almost the entire way. But these are quite typical miles for cruisers, hence the high typical engine hours per 1000 miles traveled. It doesn't bother me as much as it used to.

[boatman61]

Actually cats used to flip back in the day.. before the snotty designers conceded Wharram was right and started to design wider beams.
Why do you think masthead floats were created back in the 70's when many here were bearing off shop windows with lollipop sticks, not ships sides with boat hooks

[boatman61]

Another thing.. at 4.5ft draught per hull on a L450 its not so much an easily driven hull that gives a cat that extra speed IMHO, its the lightness and rigidity of the 50%+ to length beam that provides wind resistance and keeps positive thrust to a max.. my Tiki's used to sail so fast I would find my jib luffing on beam reaches.. unlike a mono which heels as a result of wind force leading to spillage.
This however is a handicap going to windward for cats as the monohulls ability to lean maintains/improves the aerodynamics of the sails.
But hey, what do I know..

[Bigmarv]

Originally Posted by Dockhead

Well, but that's the way 90% of catamarans are used, also, isn't it? Easily driven also makes a superlative motor boat, and it's much less trouble to light up the Yanmar than it is to get a non-white sail up.


I have seen Dashew boats sailing superbly well in light wind, but -- using non-white sails. Just like the performance cats I know. Short handed crews of both types of vessels usually use the motor instead, and I don't think there's anything particularly "American" about it.




The Dashew boats are somewhat limited upwind most of all by their shallow and non-bulb keels, I think, something I would not like. On a mono, there is no substitute for draft for getting upwind. But AFAIK the Dashew boats are not actually too shabby upwind despite that -- the key being the lightness, long waterline and speed potential, which cuts down leeway and allows you to achieve high VMG to windward despite modest AWA angles. The same principle by which some even non-performance cats without boards do surprisingly well upwind, contrary to the prejudices of many mono sailors.



But again, the crew has to be willing to be bothered. Cat or Sundeer, most crews choose to motor upwind rather than tack if the sea state is reasonable.


I've been doing it myself lately, despite my carbon sails and great efforts to make my boat sail well upwind. Last big trip I did was last month, from Cowes to Helsinki in 9 days with only 3 stops. We averaged about 150 miles a day including the stops. I was in the middle of stuff with work and was not able to take time off to do this trip slowly. Unfortunately in May the prevailing SW winds are frequently reversed to NE, and we had to make a lot of miles directly upwind. As long as the sea is not up so much that the head seas are stopping you, you can just hand over to Mr. Yanmar and let him deal with it, and go directly against the wind if you want, saving vast amounts of time either tacking or waiting for a wind shift. Motoring against 15-20 knots of true wind but with seas not too steep I can generally make about 7 to 7.5 knots using about 2500-2600 RPM. It burns some fuel -- maybe a liter per mile -- but there is no way to come anywhere close to that speed in VMG made good to windward by tacking. Of course that all changes with a little more wind and/or a little steeper seas.



This is different from open ocean sailing where you can do tactics and head off waiting for a wind shift and play the wind shifts -- this was 1300 miles with routing constraints including TSS's, wind farms, coasts, etc. almost the entire way. But these are quite typical miles for cruisers, hence the high typical engine hours per 1000 miles traveled. It doesn't bother me as much as it used to.

I'd be pretty surprised if expensive sails cured the Dashew shortcomings - they're just baked in. Dragging a submerged stern and a little keel along with not much canvas is never going to be great upwind especially in the light. This isn't controversial and that's why it's consumers (and not designers who want their boats to sail well in those conditions) who always regard Dashew as a genius.

Their boats and their passage times came from an era when the consequences of burning fossil fuels were not properly appreciated and where the Dashews were prepared to define 'good performance' as excluding the things their boats were not good at.

That people would still be putting the hammer down for thousands of miles in a pure leisure sailing context is saddening.

[fxykty]

Originally Posted by boatman61

Another thing.. at 4.5ft draught per hull on a L450 its not so much an easily driven hull that gives a cat that extra speed IMHO, its the lightness and rigidity of the 50%+ to length beam that provides wind resistance and keeps positive thrust to a max.. my Tiki's used to sail so fast I would find my jib luffing on beam reaches.. unlike a mono which heels as a result of wind force leading to spillage.
This however is a handicap going to windward for cats as the monohulls ability to lean maintains/improves the aerodynamics of the sails.
But hey, what do I know..

You know a whole lot more than me, but I think you’re not quite right that heeling is what makes sails more efficient. Racing sailors do all they can to keep their boats as upright as possible, and not just because modern hull forms are better upright. ORMA trimarans among others cant their rigs to windward to counteract their 10 degrees of heel for better performance.

Think about the force vectors - any component that heads down towards the water adds to the drag and lessens the value of the component going forward and parallel to the surface.

Are you thinking of baggy overly-full sails that can be a problem with low rig tension?

As for the L450, the wide hulls and the high and upright superstructure of that class of boats are what cause it to suffer upwind due to excess drag - not anything necessarily to do with the sails.

[boatman61]

Originally Posted by fxykty

You know a whole lot more than me, but I think you’re not quite right that heeling is what makes sails more efficient. Racing sailors do all they can to keep their boats as upright as possible, and not just because modern hull forms are better upright. ORMA trimarans among others cant their rigs to windward to counteract their 10 degrees of heel for better performance.

Think about the force vectors - any component that heads down towards the water adds to the drag and lessens the value of the component going forward and parallel to the surface.

Are you thinking of baggy overly-full sails that can be a problem with low rig tension?

As for the L450, the wide hulls and the high and upright superstructure of that class of boats are what cause it to suffer upwind due to excess drag - not anything necessarily to do with the sails.

Thanks for confirming my remarks.. the more vertical the rig the better the performance.. except upwind where it can become a handicap if there is zero heel capability.

My Tiki's had zero superstructure but narrow V hulls with 10in draught yet they to performed poorly to windward..
Mind that was leeway if pointed to high.
Also.. I blag a lot..
Regarding mono racers, going upwind there is an optimum heel.. to close to the wind and the heel starts to diminish, to far off and it becomes excessive so one strives for maintaining the optimum by piling as much fat as possible on the rail..

[KC375]

Originally Posted by boatman61

Thanks for confirming my remarks.. the more vertical the rig the better the performance.. except upwind where it can become a handicap if there is zero heel capability.

My Tiki's had zero superstructure but narrow V hulls with 10in draught yet they to performed poorly to windward..
Mind that was leeway if pointed to high.
Also.. I blag a lot..
Regarding mono racers, going upwind there is an optimum heel.. to close to the wind and the heel starts to diminish, to far off and it becomes excessive so one strives for maintaining the optimum by piling as much fat as possible on the rail..

The only way I can think of leeward heel making a contribution to / through aerodynamics is in very light wind conditions where gravity can help create a desired sail shape that might otherwise be created with stronger wind.
Introducing leeward angle to the sails merely reduces the share of aerodynamic lift from the sail that is in desired direction. This increases drag.
In high performance boats the mast (some multihulls) or boat (e.g. moths, UFOs) is intentionally angled to windward.
However, the hydrodynamic effects of heeling to leeward is often positive - reducing wetted area (e.g. scows) and creating an asymmetric hull shape in the water that may produce lift to windward.
If the boat is over canvassed/overpowered then yes heeling can “spill” the wind but that is by definition the wrong solution. A boat is only overpowered if the sail area is heeling the boat beyond the optimum point for immersed hull shape and efficient lift from the keel/board...going beyond that heel to “spill” wind is by definition sailing with less efficient hydrodynamics. You produce better performance by shortening sail.

[boatman61]

Nicely put..
But I still maintain heel going upwind has both aerodynamic and hydrodynamic benefit.. with the correct sail area and wind angle.

[Dockhead]

Originally Posted by Bigmarv

. . . That people would still be putting the hammer down for thousands of miles in a pure leisure sailing context is saddening.

Well, for whom how, as the Russians would say.


There are lots of different reasons for wanting to get from one place to another in a "pure leisure sailing context". Someone sailing purely for fun around a coast without any big mileage to cover is one case. Someone sailing from here to there in a mild latitude with plenty of time to wait for the right wind or sail indirectly to get there, is another case. And someone who needs to get somewhere for some reason, and that somewhere happens to be upwind -- that's yet another case. And the answers are all different.


Latitude counts for a lot. Up here the seasons change much faster and the weather windows are much tighter. Calm weather is relatively rare and a dead calm is an excellent weather window if you're making miles up here for some reason. I motored all the way from Northern Greenland to Iceland last summer -- four days and nights -- in a dead calm between two howling weather systems. It was somewhat boring and you do get tired of listening to the engine, but compared to bobbing around and waiting to get smashed by that deep low rolling in from Newfoundland? No thanks!



I'm not a bit ashamed of "putting the hammer down", when I feel like it! It's great to have the option of sailing or motoring, according to what you're dealing with.


Excellent sailing ability and excellent motoring ability are not mutually exclusive design values. An easily driven hull promotes both.

[KC375]

Originally Posted by boatman61

Nicely put..
But I still maintain heel going upwind has both aerodynamic and hydrodynamic benefit.. with the correct sail area and wind angle.

I may not be understanding you properly.
If the sail is angled to leeward a portion of the force it produces is angled downward.
Please help me understand how introducing or increasing a downward force improves performance. Particularly as this downward force’s effective center is to leeward of the center of buoyancy.
Try this thought experiment. Break up the forces of the sail into those generated as if the mast were vertical and the remaining force you would have in a downward direction. You would end up with a smaller sail area with a vertical mast and a downward force somewhat like hanging a heavy weight off a pole to leeward...