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Tuesday, February 24, 2015

DOES CRUISING BOATS NEED "TRAINING WHEELS"?


On the cruising forum where I post as "Polux" I have posted something about hull shapes and performance that may be interesting to this blog. The post is here (post 258):
http://www.cruisersforum.com/forums/f47/true-blue-water-boat-extinction-a-fait-accompli-141354-18.html#post1754758
From here comes the basic question: The qualities that make a good racing solo sailboat are relevant to a cruising boat? Or putting it another way, the type of hulls and rigs used for solo racing are relevant for cruising, as a benefic global influence that can allow better cruising boats? The type of hull that allows a solo sailor to push and sail fast (many times under autopilot) a racer through ocean has advantages for an inexperienced, solo or short crew cruiser while sailing offshore on a cruising boat?

As a way to answer let's have first a look at the differences between the type of hulls used for solo racing and the type of hulls used for crew racing: Many think that the very beamy Open 60 are the fastest type of boat downwind (for the size) or on a circumnavigation but they are wrong. Certainly they are the type of boat faster sailing solo on a circumnavigation but not if a crew is used. On that case a boat like the VOR65 (with 60ft) will be faster, provided it has a full crew to handle it.

Let’s have a look at both hulls, a VOR 65 and a Open 60 (both sailboats designed for a circumnavigation on the trade winds, meaning mostly beam reach and downwind sailing):

The difference is evident, both have all beam pulled back but the Open 60 is a much more beamier boat. So why not make an Open 60 less beamier and theoretically faster? It has been made…and did not work out, they have been developing these boats for 30 years, and the actual configuration it is the one that at the moment allows for a faster boat…sailed solo. Why?

Let’s look at some videos of 11/12m racing boats, solo racing boats and crew racing boats to understand why. First a Beneteau Figaro II versus a J111. Both boats can go damn fast downwind, the J111 even faster but look at the guy on the Figaro that can leave the boat on autopilot to adjust sails or even to go ahead to set the Spinnaker. He has to leave it on autopilot on many occasions inclusive to sleep.
 
Compare with the guys on the J111, even with a short crew they need three guys to keep it out of broaching, one at the wheel, other constantly trimming the front sail and a reserve one for the mainsail or for helping if something goes wrong. The J111 is a cruiser racer, if look to truly race boats, like a Soto 40 or a Ker 40, the control has to be even more precise and a bigger crew is required:
Now compare with a same sized solo racer, a 40class boat sailed by a lonely sailor and will be on a completely different ball game. One guy is enough to drive the boat fast downwind, not as fast as a ker 40 or Soto 40, but certainly much faster than a Soto 40 or Ker 40 solo sailed. On a solo racer the boat has to be handled many times on autopilot since it is the same guy that is the trimmer, the bow man, the navigator the helmsman….and it has also to work on the winches and to sleep since most of the races on those boats are Transats or circumnavigations.
Bob Perry said once that those boats had training wheels and that he didn't need any training wheels on his boats. So the question is, do cruising boats need training wheels, meaning they can be sailed faster and safely with them …or maybe not?
J111
Luca, the guy from Comar maintenance said that he was part of the crew that test sailed the first Comet 41s (my boat) and that on the maiden sail they had sailed it at 18K. Well, I have owned my boat for two years now and I have never went faster then 14K (and even so on only one occasion) and I know that I will never sail it at 18k simply because for that the boat needs a crew. Don’t make me wrong, that is a fast boat and a relatively easy boat to sail with a huge resistance to broaching and an incredibly sensible rudder. Just with a bit of help with my wife, or even solo I can sail pretty fast on it, specially upwind but the downwind sailing speed (no spinnaker) is most cases between 9.5 and 11.5K, a bit more in  really strong winds, not anything closer to 18K. That is what the boat can do with a full crew and a spinnaker up in strong wind.
J111

My friend Eric, that is not much younger than me, said it has not taken him much time to sail his Pogo 12.50 to 13/14K and that is a speed that he reaches with some ease on the right conditions. I may be wrong but I seem to remember that he said that he had done once or twice 16/18K with his boat, with the help of the family crew, that includes not only a wife but a son also.

Me and Eric are the kind of cruisers that like to go fast, most cruisers will sail more calmly but the point is, would not this difference in easiness (that has to do with the hull of the Pogo to be derived from solo racers, while the one of the Comet is derived from IRC racers) will not suit even more less demanding sailors? I think that the answer is a clear yes and that’s why most contemporary NA use hulls influenced by solo racers in almost all main market production sailboats and in voyage boats too. The ability they have to go with more easiness, with more directional stability from a beam reach to downwind makes more efficient on autopilot that’s what most cruisers use while sailing. That type of hulls makes also for a more forgiving boat that can take more abuse without broaching.
Beneteau Figaro II

So what about upwind sailing? will more narrow boats, or IRC derived hulls, like the ones of the Salona or Dehler, Comet or J122 perform better? The difference will be not much on flat seas, just a bit better pointing ability but on  nasty seas or even on the typical med short period steep waves there will be a big difference due to wave drag.

While sailing on flat water the waterplane (and wet surface) of the boat like the Pogo will be a very narrow one, having to do more with its weight than with its beam but while passing waves all change: The wave envelopes the boat that passes through it and increases hugely the wet surface associated to wave drag that is much bigger on a solo racer beamy type of hull than on a much narrower IRC derived one. The beamy hull will suffer much more drag for each wave it crosses than the IRC type. Sure it can fly more sail due to its much bigger hull form stability but that will not even the match. The boat will have to open more the course (to gain power), probably it will go a little faster, storming through the waves (and that is less comfortable) and in the end it will be slower, or at least is what I have taken from the observation of race results even with more powerful 40class racers (on the Sydney Hobart and Med races).
Soto 40

Heavier boats with this type of hull, like the Oceanis 38, 41 or 45, Dufour 410, 500 (among others)  will have about the same comparable characteristics regarding cruisers with about the same weight and hulls influenced by IRC hulls, like the Jeanneau 409.

Is this less good performance upwind on some particular conditions a big disadvantage? Not for voyage boats that mostly will follow the trade winds, not for main market mass production boats because even if most sail on the med where these conditions can be met, most sailors just don’t go upwind on those conditions (over F4) or just motor most of the time when sailing directly upwind.
40class racer
That explains why the open solo race type of hull is the main influence on cruisers today: it just offers the best compromise for most sailors, not forgetting the big advantage that a bigger interior represents for cruising, in living space and storage.

Of course that does not mean that even in what regards cruising that would be the best compromise to all. There are many variables here and one can just prefer a narrower boat because it just likes more the way a boat sails on a seaway, because it is more nervous and fun to sail, because it values more upwind sailing or just because he finds narrower boats more beautiful. All good reasons. ;-)

7 comments:

  1. The last Sydney - Hobart was a good example about. When off wind the Comanche sailed well over 20 knots, but when up wind in very soft wind Comanche sailed at just 2 knots when Wild Oats sailed at 7 knots.

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    1. Yes, even if there we are talking about two boats with full crew. It is amazing how the boats being so different had a a so close performance. The Sydney Hobart and Med/Baltic races are the only conditions where Wild Oats could fight Comanche and eventually win. On a Transat or circumnavigation race the Comanche will be much faster.

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  2. I think you’re absolutely right, Paulo. It is indeed quite easy to bring these open-type designs such as the Pogo 12.50 into full planing mode and reach constant speeds of 13-14 knts, even without waves to surf off. With waves and a good driver we’ve hit top speeds of 18 knts and more several times.

    Apart from the driver, trim and waves, one more very important factor on these boats is weight. That’s why our youngest son has been appointed our “weight watcher”: any peace of gear or equipment will have to prove it’s worth the kilogrammes before he allows it on board. That’s something to bear in mind for long distance passages, because the boat will then inevitably be somewhat overloaded.

    I can confirm your explanation about wave drag and sometimes uncomfortable behavior upwind in short and steep seas. We then push the bow 5° lower to widen the wave angle and build more power. I doubt we would be able to follow your Comet when beating, but in comparison with most production cruisers we achieve the same VMG because we sail lower but faster.

    And indeed the large beam aft creates a huge amount of interior space, so it takes extra character not to fill it up with all kinds of stuff…

    Best regards,

    Eric

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    1. Great comment. It sure makes the post a lot more rich. Thanks!

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    2. But narrow light boats are faster than that! For example in one of the test of the Summit MD 35, a very narrow daysailer the writer said that they sailed at 18 knots without effort, and here is a video were this boat register a max speed of 19.1 knots sailing from Buenos Aires to Mar del Plata, in Argentina, a 250 miles race.

      https://vimeo.com/63982949

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    3. Pedro, I think you are missing the point. Nobody is saying that narrower boats are not faster then beamier boats derived from solo racers, just that for sailing them fast you need a crew while on boats with hulls derived from solo racers you can go fast alone and much more easily On the movie you have linked the boat is sailed by three experienced sailors.

      I have no doubt that a Soto 40 or a Ker 40 are faster then a Class 40, if they are sailed by an experienced racing crew, but solo sailed or with a short crew, the Class 40 will be much faster the same way a class 9.50 will be much faster solo sailed or duo sailed than a Summit 35.
      https://www.youtube.com/watch?v=9OL4QPgr-Dw

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  3. Correntoso Surfer, the boat in the video, race usually in the two men crew division in Buenos Aires. This boat was designed to be sailed by short crew or solo. To compensate the crew weight she has a deep keel and a heavy bulb.

    From Summit Yachts: "This stylish, simply-conceived yacht can be ready to sail in minutes and is perfect for daysailing with family, friends, or solo."

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