Are all multi hulls so noisy and unpredictable?

[Master56]

[QUOTE=Factor;3527309]

Originally Posted by Master56

I am not -

Hilarious, says it all really. Why the hell are you hanging around us poofters in the Multihull Forum? You ready to come out of the closet.

****, am I in the multihull forum!! Don't tell my mates I'll never live it down. I thought I was in the general yachting forum discussing whether all multi hulls are noisy and unpredictable.

[Factor]

Originally Posted by Master56

****, am I in the multihull forum!! Don't tell my mates I'll never live it down. I thought I was in the general yachting forum discussing whether all multi hulls are noisy and unpredictable.

You thought Wrong, but you must be fairly used to that by now.

[mark_morwood]

Originally Posted by Joli

Do you consider 70 TWA upwind?

When cruising in this particular context yes, though I understand I might not have been clear enough. The destination was definitely upwind of us, just not dead upwind.

Racing obviously no. Given this is "Cruisers Forum" that's the context in which I was writing.

And once again, I was not trying to claim some great upwind performance, I was just showing that you can have a reasonable ride in "sporty" conditions with the wind forward of the beam. That catamarans can work fine in a wider range of conditions than some suggest.

[Master56]

Originally Posted by Factor

You thought Wrong, but you must be fairly used to that by now.

[Sail IC]

Originally Posted by Budawang

Used to be part owner of a 2009 FP Lavezzi which is one of the nicer looking and better performing production cats. Nice boat but it did make a lot of noise under way. The starboard hull creaked like crazy and there was a lot of noise from the water rushing under the bridgedeck. Motion was rather jerky in most conditions with constant small accelerations and decelerations. At the end of a long passage I was exhausted and my wife often got sea sick. My much heavier monohull is way more comfortable underway. However, at anchor a catamaran is unbeatable.

I have a FP Orana, similar to yours. I agree with your issues with sailing this type of cat. I mono however heels at wind pressure and roll downwind in seas. To me makes them uncomfortable and less safe especially if you need to go forward to the mast. A friend when crossing the Atlantic westward in a heavyish mono had to sleep on the floor as the boat was rolling so much.
Nothing is perfect, so we all pick what is right for us and what we want to do.

[catsketcher]

The issues of comfort as I see them are acceleration magnitude, number of accelerations, magnitude of roll and distance from roll centre.

My cat has a quicker acceleration than my friend's heavier cat (that sailed around the world) I quite liked its motion in a slop, although I didn't like the higher loads on the sheets - because of its extra weight and size.

But when I sail a mono I often get surprised by how much further the boat will roll. With less initial stability, monos roll over so that the things I don't stow fall off the table. Whereas on my cat I usually leave stuff on the benches.

Mono designers also know about high initial stability. Boats with high initial stability have a snappier motion. Your beamy Bavaria will have a snappier motion than a Hereschoff 36. Bob Perry talks about how it is hard to get people to accept lower initial stability but greater comfort in his mono designs. Cats are even snappier than the snappiest mono with their very high initial stability. Perry likes soft initial stability and the gentler motion in a seaway. Cats can't get around this issue.

One thing cat designers can do to increase comfort is to locate all heavy objects in the centre of the boat. Although this will increase the rate of acceleration, by making the boat easier to pitch, it will reduce the amount of energy required to pitch the boat (by getting the bows tp be less immersed
in waves and produce less pitching angle). Also it will produce much faster pitch damping.

One also has to remember that ANY weight out from the pitch centre will cause problems with pitching, so higher and heavier cabins, flybridges and cockpit enclosures will add to pitch issues. Having high cabins and then adding on a taller mast will exacerbate the issue.

I like being able to sit about 60% of the way back from the bow when sailing. Going to windward, the boat pitches around this point and so sitting (or even better, standing and holding on) at this position allows the boat to rotate around me. If I stand on my step into the hulls and gently hold on, the boat pivots around my feet and it is quite smooth. If you get into a flybridge you will be further from the pitch centre and experience greater acceleration from a certain amount of pitching (as well as adding your weight to the pitch moment). One person up the bow of my cat makes her crankier. Three in a flybridge would do the same.

Next time I head offshore I could grab my phone and use the accelerometer app to work out the magnitude and directions of accelerations we get subject to. It would be interesting to see the diversity on different boats.

cheers

Phil

[Seaslug Caravan]

Originally Posted by Joli

Do you consider 70 TWA upwind?

Good question, well asked.

70 TWA would be considered a sweet spot along with 110 to 120 for a Cat.
Not many would consider it as genuine upwind work. More of a “Reach.”

I have now owned my cat for close to 30 years with many Miles under the keels and I wouldn’t swap it for anything, but you guys must not get out much if you think bashing and crashing to windward is a blue water catamarans forte.

The pictures posted earlier of a posters cat sailing to windward on a calm day is not typical of the real world.
There’s nothing like crushing waves into submission when working to windward with an enormous amount of lead ballast.

Light weight and shallow draft wins out for me overall however.

PS

Can’t believe I missed out on so much of this fun thread. I must be slipping.

[Factor]

Originally Posted by Seaslug Caravan

.... Miles under the keels ....

There is your problem and I fully understand now why you dont get how well a perforce multi can work

[Tupaia]

Originally Posted by catsketcher

Next time I head offshore I could grab my phone and use the accelerometer app to work out the magnitude and directions of accelerations we get subject to. It would be interesting to see the diversity on different boats.

cheers

Phil

Phil, I think you nailed it excellent explanation.

One thing you missed, in my experience boats with lower initial stability increase the prevalence of seasickness even at anchor.
You could extend your accelerometer idea by taking readings at different positions around the boat, bow, stern, helm etc.

[catsketcher]

Originally Posted by Seaslug Caravan

Good question, well asked.

70 TWA would be considered a sweet spot along with 110 to 120 for a Cat.
Not many would consider it as genuine upwind work. More of a “Reach.”

I have now owned my cat for close to 30 years with many Miles under the keels and I wouldn’t swap it for anything, but you guys must not get out much if you think bashing and crashing to windward is a blue water catamarans forte.

The pictures posted earlier of a posters cat sailing to windward on a calm day is not typical of the real world.
There’s nothing like crushing waves into submission when working to windward with an enormous amount of lead ballast.

Light weight and shallow draft wins out for me overall however.

PS

Can’t believe I missed out on so much of this fun thread. I must be slipping.

The pic was a lovely one showing Kankama gliding along to windward on a fab day - behind the reef for sure, but the reef is about 30 miles to windward and the wind is 15 knots, enough for some chop. It is only one of many days spent going to windward - like the day after day spent beating into the wind to get from Lizard south when the northerlies wouldn't blow. She has cruised from Lizard to Hobart with many days to windward. I live on the NSW coast and have chugged to windward for many miles in the open sea - there just hasn't been a friend along to take a pic. But that pic is of the real world, showing what great sails you can have with a windward witch when the others are chugging away with the main up and the diesel on and wishing the miles away whilst we had another wonderful sail to windward, again.

To be honest I don't beat to windward for more than about 50 miles in a day, but I have done so on too may days to count, and often we are one of the few boats sailing -we don't have diesels to pound to windward, and rarely have we been passed by another cruiser. A great sailing windward cat will feel like she is having it easy when you can crack off 10 degrees. Good windward performance opens up the available windows for sailing.

As to lead being essential for windward wave smashing, I disagree. The boats I like work collaboratively WITH the wind, rather than fighting the elements, be they mono or multi. Getting thrashed and bashed is usually slow, being efficient and slipping along is usually the fastest comfortable method. I speed up until it gets too hard to hold on and then throttle back. Most of my time sailing in tradewind windspeed is spent throttled back. Everything loosey goosey and fun. The boat slipping along and me just helping her to do her thing - it never gets old.

[waterman46]

Every Beneteau and Jeanneau monohull I have boarded at boat shows led me to disapointment at how poorly the flooring was designed and installed. Creaky and bendy. Suppose it would be more so in a seaway.
I don't think catamarans have the noisy boat market to themselves.



Older boats, monohulls in general because weight is/was not so much of a problem, will be quieter. But heavy, quiet and comfortable for a given boat size means slow - my Morgan 46 being a good example. Have never heard any squeaks or groans from the woodwork in any conditions.

[Happ]

Originally Posted by dr.j.levy

Hello all,

Recently delivered a Lagoon 50 over 4 days in the Med. I stand in shame, but all my experience in life is on single hulls.

Anyway, sea was rolling up to 2.5m - 3m waves....interior on this 2 year old cat supper noisy and squeaky for 1m boat, BUT bashes on inner hull from waves almost brought a halt to the movement every odd minute and certainly did not let you sleep. One small thing that bothered me is that you could not predict the movement of the boat to brace yourself. Its like a toast on the water rolling whichever the third or fourth wave chooses.

Is this normal also cats which are not Lagoons? I am told this is normal Lagoon behaviour. If it is normal, cats should only be sailed on flat seas under motor...sorry if this offends anyone.

Cheers
Joel

The answer is 2 fold. Yes on almost all catamarans are noisy when waves hit the inner hulls and yet he bottom of the Bridge Deck. The interior creating depends on the manufacturers construction process. On your better builds all the “furniture is laminated in. Outremer is one manufacturer that does this. Being laminated in it helps stiffen the boat al well as eliminating the noise when the hull torques as all boats do. The production boats basically bolt the interior in. When the hull torques the furniture is either twisting or the furniture is rubbing against the hull.

As to the boat stopping when hit by a wave. These boats do not point well even though the sails seem trimmed. Foot of 3-5 degrees. That will help out a lot. I learned this sailing trimarans. Your VMG will make up for the Los of pointing pl;us a much nicer ride.

[redneckrob]

Originally Posted by Happ

The answer is 2 fold. Yes on almost all catamarans are noisy when waves hit the inner hulls and yet he bottom of the Bridge Deck. The interior creating depends on the manufacturers construction process. On your better builds all the “furniture is laminated in. Outremer is one manufacturer that does this. Being laminated in it helps stiffen the boat al well as eliminating the noise when the hull torques as all boats do. The production boats basically bolt the interior in. When the hull torques the furniture is either twisting or the furniture is rubbing against the hull.

As to the boat stopping when hit by a wave. These boats do not point well even though the sails seem trimmed. Foot of 3-5 degrees. That will help out a lot. I learned this sailing trimarans. Your VMG will make up for the Los of pointing pl;us a much nicer ride.

On my Fountaine Pajot all the squeaks come from the paneling rubbing against other paneling or the liner. It is all glued on, not bolted. The furniture doesn't squeak at all. It's kind of a tradeoff, if they left bigger gaps on the paneling or left bigger gaps and maybe caulked them there wouldn't be any squeaking but it would look worse. The boats are designed to flex, they weight would be prohibitive otherwise and cats are very weight sensitive, so it's a bit of an intractable issue.

[GRIT]

Originally Posted by Master56

I raise another rubbish. You must be talking high tech multis and trimarans or you are racing against incomparable monos to your tri.

PS. Once upon a time, for a joke, I designed a motif for a T-shirt with 'Catsareforpoofters - Club President.' Crikey the cat fraternity didn't see the funny side of it and I nearly got linched. It was pre-touchy-feely era.

Call me a contrarian, but I'd love to have that t-shirt! If you have one in a size small, please PM me.

I think our world is losing it's sense of humour, and folks take themselves much too seriously.

I don't care much about the whole cat/mono thing. I've owned both, and prefer our Cat. Some will disagree, and I'm ok with that.

Cheers.
Paul.