Why Do Catamarans Motor Nearly 100%

[Polux]

Originally Posted by 2Hulls

So? What is the obsession with tacking angles? Guess what angle the foiling AC cats tack through? 100 degrees (50 using your tacking angle description). Does that make them worse upwind than a "good monohull" 10 to 15* better? VMG is the relevant measure.

My experience sailing side by side with the better cruising monos of similar length tells me that they cannot make better VMG once the wind speed exceeds that necessary for them to get to hull speed.

Dave

Yes I agree, what is important is the VMG and again I was only talking about condo cats having a poor VMG upwind. That is the only thing that is relevant to this thread because that will lead them to motor more when going upwind than many monohulls.

Yours in not a condo cat and regarding the comparative performance what pisses me is this type of generalizations:

Originally Posted by arsenelupiga

...
So, condomarans are 15 to 25 % faster than similar length mono over decent track seem about right.

Regarding the comparative performance of your boat upwind (VMG), some performance monohulls will be faster, other slower, you have to see boat by boat.

For instance you have on the ARC two Outremer 51, the faster not being able to beat a slightly smaller performance monohull cruiser, a Knierim 49.

That is downwind, upwind the knierim will have a comparatively better performance than downwind.

Is that strange? No, the IRC rating of the Knierim 49 is 1.231, the one of the Outremer 51 is 1.165 so it is no surprise the Knierim to be ahead of the 2 Outremer, except for the ones that think that performance multihulls of the same size are always faster than performance monohull cruisers.

That means that the Knierim 49 is a faster boat than the Outremer 51 and that both boats are well sailed.

(For the ones that don't know, contrary to the PHRF rating, on IRC bigger numbers indicates faster boats)

[admiralslater]

here is a picture of me not sailing I hope you can open it

[admiralslater]

trying again

[2Hulls]

Originally Posted by Polux

For instance you have on the ARC two Outremer 51, the faster not being able to beat a slightly smaller performance monohull cruiser, a Knierim 49.

I would not consider the ARC to be a good yard stick. While I have not participated in the ARC, I have made numerous, long offshore passages and achieving the best speed has never been my priority. I strive to achieve the best and safest comfort via picking the best weather window for the minimum amount of work and maximum enjoyment. I suspect certain ARC participants have a similar approach. We typically arrive rested, with few breakdowns <knock, knock>, and fish in the freezer.

Dave

[Polux]

Originally Posted by 2Hulls

I would not consider the ARC to be a good yard stick. While I have not participated in the ARC, I have made numerous, long offshore passages and achieving the best speed has never been my priority. I strive to achieve the best and safest comfort via picking the best weather window for the minimum amount of work and maximum enjoyment. I suspect certain ARC participants have a similar approach. We typically arrive rested, with few breakdowns <knock, knock>, and fish in the freezer.

Dave

That is not the point. The point is the fact that the IRC rating of the Knierim 49 is higher than the one of the Outremer 51, meaning a faster boat. That to be confirmed on the ARC means only that both boats are sailed at a similar level.

[tp12]

Originally Posted by Polux

That is not the point. The point is the fact that the IRC rating of the Knierim 49 is higher than the one of the Outremer 51, meaning a faster boat. That to be confirmed on the ARC means only that both boats are sailed at a similar level.

I don't think you're comparing apples with apples here. Here's the link to the kneirim 49 - Knierim Yachtbau - DAWN - 49' Performance Cruiser

So you read a little about the boat and "DAWN was built in 2004 as a competitive racer. Thanks to using the latest technologies she is a light weight but stiff boat making her also a comfortable cruiser for just a crew of 2. Right after her launch DAWN won the "HSH Nordbank Cup 2004" proving her excellent sailing performance."

Then you look at a few pics and it's a flat deck raceboat with some (very small for a 49' boat) accommodation in it, which is why it's only comfortable for two. This is very much a boat designed for racing first and deserves it's higher rating than the Outremer 51, which is a boat designed for cruising first.

I'd very much like to be racing a Knierim 49 here in Sydney though the Sydney 36 I do race on is pretty sweet too. And we've got a good crew, which is half the battle.

[tp12]

The Knierim 49 is an all carbon boat too.

[Polux]

Originally Posted by tp12

I don't think you're comparing apples with apples here. Here's the link to the kneirim 49 - Knierim Yachtbau - DAWN - 49' Performance Cruiser

So you read a little about the boat and "DAWN was built in 2004 as a competitive racer. Thanks to using the latest technologies she is a light weight but stiff boat making her also a comfortable cruiser for just a crew of 2. Right after her launch DAWN won the "HSH Nordbank Cup 2004" proving her excellent sailing performance."

Then you look at a few pics and it's a flat deck raceboat with some (very small for a 49' boat) accommodation in it, which is why it's only comfortable for two. This is very much a boat designed for racing first and deserves it's higher rating than the Outremer 51, which is a boat designed for cruising first.

I'd very much like to be racing a Knierim 49 here in Sydney though the Sydney 36 I do race on is pretty sweet too. And we've got a good crew, which is half the battle.

Yes, it is a performance cruiser that can be sailed by a couple and that can be raced competitively. I think the Outremer 51 can also be raced. Regarding the interior it is a very comfortable one, coffee machine and all. I would love to have one of those. Yes, two very different boats, but both performance cruisers.





The point here is not to discuss if one would prefer to cruise on the Outremer 51 or on the Knierim 49, regarding that I am sure that there will be different tastes, the point is that both are performance cruisers, the Knierim is smaller and faster.

The Knierim 49 is not the only performance cruiser very fast and with these characteristics, the Marten 49 that some years ago made a fantastic ARC, has a similar performance. Some boats are used more for racing, others more for cruising.

[Polux]

Originally Posted by tp12

The Knierim 49 is an all carbon boat too.

So? Have you anything against carbon boats? I don't think it would be much more expensive than an Outremer 51, if more expensive at all.
As i said the point is not that, the point is that the Knierim 49 is a monohull performance cruiser, smaller and faster than the Outremer 51.

If you think that I am saying that monohulls are faster than catamarans you got it wrong. I am saying only that you have to look at each particular boat to know who is the faster one, even among cats and monohulls with the same size.

For instance and continuing with IRC ratings and getting back to condo cats, that was what I was discussing, let's compare them with "condo" monohulls: a Lagoon 560 has a rating of 1091, a Hanse 505 1121 and a Beneteau Oceanis 50 1107. This means that the Hanse 505 and the Oceanis 50 have the potential to be faster than the Lagoon 560 if all boats are sailed with the same level of skill.

Again, I am not meaning that monohulls are faster than cats, a smaller performance cat can be much faster than the Lagoon, the Hanse or the Oceanis. I am only saying the obvious: you have to compare boat by boat and not make unsubstantiated general statements like trimarans are faster than cats or cats faster than monohulls.

[admiralslater]

Another picture of a Catamaran Sailing, which I think was the point of the original post. It has carbon daggerboards if that helps.

[tp12]

My point being you're comparing a carbon, flat deck race boat with minimum accommodation designed for maybe convincing the racer's wife that some harbour/coastal cruising will happen to a GRP boat designed for world cruising, fast. There's no minimum accommodation nor are there design compromises for racing. A racer/coastal cruiser compared to a performance world cruiser. Very different design purposes; apple and orange.

[tp12]

The catamaran equivalent of the Knierim would be something like a Crowther pod-cat. Designed for racing/speed first with restricted accommodations also added for minimal cruising.



I don't think the Knierim would get a glove on the pod-cat, at any angle or wind speed.

[Polux]

Originally Posted by tp12

My point being you're comparing a carbon, flat deck race boat with minimum accommodation designed for maybe convincing the racer's wife that some harbour/coastal cruising will happen to a GRP boat designed for world cruising, fast. There's no minimum accommodation nor are there design compromises for racing. A racer/coastal cruiser compared to a performance world cruiser. Very different design purposes; apple and orange.

I guess you did not saw the interior well:

You are entering on the subjectivity matter of what each sailor prefer regarding a performance cruising boat. There are tastes for both types and it makes no sense to say that a boat like the knierim 49 is a coastal cruiser. It is at least as seaworthy as the Outremer 49, if not more and has the accommodation needed for long range cruising.

Smaller boats with the same type are used for circumnavigating for sailors that obviously prefer them to cats (otherwise they would be sailing a cat).

As I say the point is not what type of boat each sailor prefers, if cats or monohulls. Obviously there are preferences regarding both types.

[tp12]

Yeah I saw the tiny interior in a 49' boat. We're not talking about sailor preferences here, we're talking design purposes. And whether you'll care to admit it or not, they were both designed for very different purposes and aren't comparable.

You can have a very nice finish on your tiny interior in the pod cat too and the pod cat's purpose is a lot more closely aligned to the Knierim. Again, the Knierim wouldn't get a glove on the pod cat on any angle or wind speed. Build the pod cat in carbon as well and the difference would be greater.

[tp12]

The Knierim would be more accurately described as a racer/cruiser. As would a pod-cat. Designed as a racer with bare minimum accommodations thrown in (2 people in a 49' boat), possibly very nicely finished. The Outremer is accurately described as a performance cruiser. Designed as a family cruising boat that can cruise the world in speed and comfort with the accommodation you'd expect in a boat that size, not restricted for racing.