Question for catamaran cruiser owners

[tim_ber]

Could you tell me how close to the edge is this boat going regarding a capsize?
http://www.youtube.com/watch?v=44x5KdciqO8&feature=g-vrec

I would like a large cruising cat one day, and I understand they have to be watched all the time (not auto pilot and make a cuppa on a windy day).

This large cat is starting to lift a hull and it makes me think they are just too near the edge of the envelope (is it because they are racing?)

In cruising terms, a reef would have been put in ages ago, wouldn't it?

Thanks

 

[bigwow]

That's a Gunboat to which normal rules do not apply, or so I'm told!

 

[whipper_snapper]

Appropriate sail plan plus "Auto pilot and make a cuppa on a windy day" is why you have a cruising cat as opposed to a monohull. You can be be reeling in the miles while sipping a G&T; provided the wind is in the right direction of course.


That cat is being pushed hard but is nowhere near falling over because the sea is so flat. Doing that in big seas would be distinctly brave.

 

[TQA]

Dat a Gunboat, and it is racing and yes it is possible it could capsize but I guess the mainsheet is NOT cleated off but held in the hand of the trimmer so it can be dumped in the event of a gust.

Hauling !

 

[25931]

Could you tell me how close to the edge is this boat going regarding a capsize?
http://www.youtube.com/watch?v=44x5KdciqO8&feature=g-vrec

I would like a large cruising cat one day, and I understand they have to be watched all the time (not auto pilot and make a cuppa on a windy day).

This large cat is starting to lift a hull and it makes me think they are just too near the edge of the envelope (is it because they are racing?)

In cruising terms, a reef would have been put in ages ago, wouldn't it?

Thanks

There is no record of a Snowgoose ever having capsized or sunk as far as I'm aware. We've sailed through big rough seas and never been aware of any danger. In flatter seas with plenty of wind she just sideslips - doesn't point as well as some but we do have a decent engine for when getting there is important.

 

[lw395]

Not ever so.
The windward hull is not fully out of the water for the whole of a wave very often.
I think it is still using a significant fraction of buoyancy on the windward hull, perhaps a third or quarter of its static position?
I think you would have to crank it on a good bit more to properly lift the hull.
Even then a good helm can sail a cat with a hull flying consistently.
If the thing heels to 20 degrees, you have a certain amount of time to lose some heeling moment before it heels to 60 degrees or so. Then the wind on the hull and bridgedeck become an issue.
It is more likely to capsize going downwind in big waves.
Looks very nice progress being made though.

 

[voyager35]

As capsizing a cat/tri is so terminal why do cruising multihulls not have a clutch on the mainsheet so that it cant get overpowered?
Does such a device exist?

 

[westernman]

I agree with what has been said above. There is no danger unless there is a very significant increase in wind speed. However........

There is a location close to the French/Spanish mediterannean border where you can go from a F4 to a F8 in the space of just 1/2 a mile. You could easily come seriously unstuck there in a catamaran if under full sail (as you would normally be in a F4).

We have been taken by surprise there in a 52 ft Pilot Cutter - going under full sail into an F8 can cause you to spill your coffee and dump the entire contents of the saloon table onto the floor..... In a catamaran the consequences are likely to ruin your day.

 

[lw395]

As capsizing a cat/tri is so terminal why do cruising multihulls not have a clutch on the mainsheet so that it cant get overpowered?
Does such a device exist?

I think people have been experimenting with such devices for many years, going back to when tri's first attempted RTW races.
The problems normally come offwind where letting the main out only goes as far as the shrouds. The only remedy at this point is bearing off. A lot!

 

[tim_ber]

Thank you.

 

[Boathook]

As others have said that is a racing type cat. On my cruising cat I set the autohelm and make tea. If I have to much sail up mine goes sideways but you are aware well before that you are over canvased.

 

[grumpy_o_g]

On a cat with dagger boards it's not uncommon to lift the leeward board so that, as the windward board comes out of the water, the whole boat slides sideways instead of capsizing.

 

[wotayottie]

In cruising terms, a reef would have been put in ages ago, wouldn't it?

Thanks

Yes.

About 45 degrees of heel is tha angle of maximum righting moment but you dont sail a cruising cat that way.

I had a Prout 33. That boat would not capsize under wind pressure alone under full sail until something over 30kn true wid - easy enough to calculate. So I did my first reef at 60% ie 18kn true. And I did the simple maths to work out wind speeds at which to put in all the other reefs.

I dont think a cruising cat requires any more careful handling than many AWB monos. The difference is that its all to obvious that you need a reef in a mono under pressure but it isnt so obvious in a cat.

 

[TQA]

Yes.


I dont think a cruising cat requires any more careful handling than many AWB monos. The difference is that its all to obvious that you need a reef in a mono under pressure but it isnt so obvious in a cat.

The Caribbean is full of cruising cats driven around by charter numpties. I have not heard of any that have capsized, even the ones leaving the lee of St Vinncet heading North with full sail up and the Christmas winds blowing.

Mind you the rigs are CONSIDERABLY smaller than the one on that Gunboat.

 

[tim_ber]

Thanks again.

 

[Searush]

I think people have been experimenting with such devices for many years, going back to when tri's first attempted RTW races.
The problems normally come offwind where letting the main out only goes as far as the shrouds. The only remedy at this point is bearing off. A lot!

Are you sure about that? Dumping the sail & bearing off will put the sails at right angles to the wind if you had been on a beat.

I'd expect to dump & turn into the wind, but I do realise that there is still a risk of centripetal force lifting the inside hull if you are going very quickly.

 

[Tomahawk]

for Gunboat read

Something like an AC Cobra
or a GT40

They ae not your average sailing catamaran...

 

[westernman]

Are you sure about that? Dumping the sail & bearing off will put the sails at right angles to the wind if you had been on a beat.

I'd expect to dump & turn into the wind, but I do realise that there is still a risk of centripetal force lifting the inside hull if you are going very quickly.

If the real wind is behind the beam, you need to turn down wind in a catamaran to bring the windward hull down. It becomes very natural after a while. The problem is when doing this, is that this also forces the bows down - so if you hit a big wave you can pitchpole. I.e. go ass over tit rather than capsize by falling over sideways.

 

[AngusMcDoon]

Are you sure about that? Dumping the sail & bearing off will put the sails at right angles to the wind if you had been on a beat. :eek

Performance multihull sailing is not like monohull sailing. The reactions you may be used to doing if overpowered on a monohull are not appropriate on a performance multihull. The correct response depends on the apparent wind, which is why a wind instrument is necessary and it is always set to apparent.

When the apparent wind is greater than 50 degrees, the correct response to depower is to turn downwind sharply. This has 2 effects...1) it brings the windward hull back down to the water if it is flying and 2) it kills apparent wind. Don't forget that these boats often sail with a boatspeed close to true windspeed, so the fact that the sails go side-on to the wind during this manoeuvre is of little importance if the apparent wind has dropped to nearly nothing.

A possible problem with this technique (apart from the mentioned leeward bow burying) is if you lose rudder effectiveness at speed - usually only happens above 18 knots boatspeed. This is when too big a rudder movement is made and the rudder stalls, a condition known as spinout. It makes a distinctive noise. The only way to recover from this is to straigten the rudder and wait for flow to re-establish. When making a depowering downwind turn at speed, it is important to get rudder technique correct to avoid this stall situation. Although the turn may be required promptly, it must be done with a small rudder movement.

I expect Searush will come out with his usual tirade against high performance boats and their complicated equipment, but it is always possible to sail a performance multihull more slowly, and anyway, not everyone wants to potter about at 4 knots with bits of wool hanging off their 40 year old rigging.

 

[Talbot]

I know of a Privilege 39 that was turned upside down in strong winds...............


But it did not happen until the wind reached 139 mph.


A long range cruising yacht needs to carry weight for water, supplies etc and this requires a different design ethos from performance catamarans which a much lighter and have much narrower hulls. A catamaran that might lift a hull in a strong wind is not a realistic cruising boat, as you need to crew it as if racing, and tend the sails.

A much greater danger for even cruising catamarans is going downwind too quickly and burying the nose and forceing a pitchpole. Therefore when cruising downwind you need strategies for slowing down!

I know of one catamaran that needed to be rescued by RNLI after loosing their rudders, and when being towed downwind initially, actually overtook the lifeboat due to the very strong winds. A drogue soon sorted that out!