SUN ODYSSEY 349

First movie with by yacht.de that had already tested the boat. The movie is very interesting not only because it is the first and because they give a good view of the boat but also because they tested at the same time a version with a standard keel and a version with the new swing keel version. The performance does not seem to be very different and that is just great.

Here is the link:
http://tv.yacht.de/video/Starke-Rivalin%253A-Sun-Odyssey-349/149df537a516e6a7642844be3ffb40b1

Eric De Smedt - SWING KEEL PERFORMANCE

Paulo,
I expected that, even with a similar centre of gravity, the swinging keel would perform at least a litlle better because of its higher aspect ratio?

Hi Eric!

If I understood rightly the new swing keel will have 2.54M while fully deployed and the standard keel will have 1.98M. I believe they are designed to provide the same righting moment. I don't have enough data on the new keel but it is possible that the weight of the keels are similar, maybe even the swing keel a bit lighter. The drag of the fixed keel will be smaller but the grip of the swing keel upwind should be marginally better, as you say, due to a bigger draft. Maybe you are right and not only it matches the performance of the standard one as it can improve a bit the angle upwind and that can be a better performance improvement than the loss due to a slightly bigger drag in all other sailing positions.

They do not mention it on the video (and the performance of both boats seem very similar) but as Anders reads the magazine I count on him to post about what they say regarding that on the test boat article.;-)

I don't know if they are going to make a deep draft performance version of that boat, I would say a torpedo keel between 2,15 and 2,30m. A keel like that should have a marginally better performance than the swing keel. Regarding the standard one with 1.98M, I think that if not better the swing keel is certainly not worse.

http://www.performanceboating.com.au/wp-content/uploads/doc/105/2013/1542-Jeanneau-SO349-inventory-2014.pdf

SO 349: MODERN SWING KEEL / MODERN TORPEDO KEEL

Let's take the opportunity that has been given by Jeanneau when they created the conditions for boat testers to test simultaneously their version of the 349 in the standard keel version and swing keel version, these two:

The drafts are 1,98m for the standard keel and 1.26m/2.54m for the swing keel. Regarding the weight of the ballast they refer the same weight, being the swing keel calculated to give the same RM but in fact I read somewhere that the CG of the swing keel was just a little bit lower and that should give it a marginally lighter keel (for the same RM). Regarding this subject I had already said:

"Lifting keels are around for many years and some, like the Southerly even have ballasted ones but only with a percentage of the total boat ballast on them, but hydraulic lifting keels with big draft and all ballast on the keel are a relatively new concept even if they are widely used already by many smaller production French shipyards.

They are by far the best solution in what regards a need of small draft maintaining boat performance in boats were a truly lifting keel (vertically) occupies too much interior space and that means all boats smaller than 40ft and even bigger.

Regarding lifting keels, if well designed on relatively small sailboats these keels have the advantage of allowing for more draft when deployed lowering the CG and giving a great performance upwind."

Eric had pointed out that the version with the swing keel had probably a better performance due to the higher keel aspect ratio and I replied saying that probably that was true regarding upwind performance but not in what regards downwind since the torpedo keel would have less drag and that if that torpedo keel was a deep performance keel, with about 2,20/2.30m, I believe it would have a better performance than that swing keel.

As the boats have been tested by several boat magazines I was very eager to see if we were right so as soon as I received Voile magazine I went for that test and I was quite pissed when I found out that they did not had taken care to verify if both boats were on the same condition in what regards tankage and they were not, having the one with the swing keel more water on the tanks (full tanks) and a stored dinghy. Even more unsatisfied when I discovered that boat test were made at the same time, with the guys from the Yacht.de magazine on one boat and the French on another (they exchanged the boats) so the same somewhat tinted results will be extensive to the Yacht.de test.

Well, something is better than nothing so the results were these: Close to the wind the performance was identical. On a beam reach the performance was identical. Downwind the performance with the boat with the standard keel was better and the boat slowly but without any doubt went away.

To know if this was due to a less drag downwind on the standard keel (since the advantage of the bigger grip of the deeper swing keel has not any beneficial effect downwind) or due to the extra 150/200kg of weight (water + dinghy) on the boat with the swing keel is impossible to know, as well as if the performance would be better upwind or on a beam reach without that weight. Anyway a very close match but one thing is true....... the SO 349 looks good with a Swing keel ;-)

Sosa - SWING KEEL UP DOWNWIND?

Hi Paulo,

First I would like to thank for not giving up and for keeping with this fantastic blog. You (as well as all the other contributors to the threat) have been a valuable source of information. It’s is the first time I ask anything in a blog/forum so here we go: Do you know whether when they were sailing downwind, the Jeanneau with the swinging keel had the keel up or down? Do you think there would be any benefit of keeping the keel up in these conditions?

Hi Ivan,

Thanks, you are welcomed. I am sure they had the keel down when sailing downwind. French aluminum centerboarders pull the keel up while sailing downwind and that allows them to sail faster with less drag but in that case the boat stability is not altered since they don't have any significant ballast on the centerboard. That is not the case with a swing keel of this type that has all the ballast on it. when pulled up you are diminishing significantly the boat stability, not a thing you want to do while sailing, even downwind.

Anders Bengs - SUN ODYSSEY 349

I looked through the Yacht de magazine boat test on the Jeanneau 349. They were in general very positive and where up to some extent surprised by the fixed keel version being slightly quicker. The polars say the opposite. But they also concluded that it was difficult to evaluate since the swing keel version had a fixed propeller and full tanks.

They say that the boats are surprisingly stiff and for that the form stability contributes a lot. They also say that the boats sails beating on choppy seas with a soft motion. They also liked the innovative interior (as I did when I saw it on the boat show in Gothenbourg).

What they do not like is the new pricing system used by Jeanneau and Beneteau. Sure, you can get a boat cheap but when properly equipped it gets expensive. For instance, the Oceanis 38 fully equipped is more expensive than the Dehler 38 standard and that with important equipment of lesser performance/technical quality.

One more comment regarding swing keels. Sure, it’s nice to get into shallow bays/harbors but while sailing I feel somewhat scared by the thought of having it nearly 3 m below the water line. In many of our marked transits, up here, and in the shallow waters near Denmark, 3 m is stretching it over some stones or sand bank. But of course, it can be always swigged up. But how well does the boat maneuver with the keel up?

Hi Anders,

Thank you very much for your collaboration that was just great.

Yes I agree with the German testers, a fixed propeller on one boat and a feather one on another will make that comparison even less accurate than the difference of weight regarding the full water tanks on only one. The French say nothing about that.

Regarding the price of equipping a standard boat with equipment, specially in what regards to better its performance, going skyrocket the ones that started with that were Bavaria and Hanse LOL. When I bought my Bavaria 36 in 2002 the standard price was about 90 000 euros and the boat costed me close to 150 000 euros ;-) Also when some years back I wanted to improve an Oceanis 37, making it a performance boat, I found out that it was not more expensive to buy a standard performance cruiser and as you say that one would come with a better performance hardware anyway.

Regarding the question about maneuverability I believe that the keel up will only make it difficult in tight port maneuvers, not in normal handling but Eric is the one that can reply to that.

Eric - SWING KEEL

A fixed three blade propeller... that must cost at least a knot and will probably be much more important for speed than the keel version.

There's absolutely no way to sail with a swinging keel partially or fully up.First because the head of the keel is only firmly held in the keelbox when the keel is fully down. As soon it is lifted, the head rotates out of the box and is not firmly held anymore. Sailing would then be dangerous.Secondly because lifting the keel shifts the CG (and lateral resistance) upwards but also backwards. This makes the boat unbalanced to sail.And third because lifting the keel does not reduce drag, on the contrary. The lifted keel is less hydrodynamic. When motoring, lifting the keel reduces speed with almost a knot.

The lifted keel increases directional stability (which is OK when motoring) but therefore reduces maneuverability, transforming the boat in some kind of a longkeeler with a greater turning circle. Add to this twin rudders that get almost no prop wash and a light hull, and you know docking this kind of boats can be challenging...

Thanks Eric,

Yes, a fixed three blade propeller would take a lot of speed to the boat. I don't know if a full knot but at least 1/2K and that is already huge. The French say nothing about the boats being equipped with different propellers and I find hard to believe that on a beam reach the boat with the swing keel (with a fixed 3 blade propeller) could have maintained the same speed of the boat with a standard keel with a feathering propeller. it just does not make sense.

Thanks for your explanation about the use of a swing keel. On the only time I sailed on a boat with one the skipper had to lower partially the swing keel to be able to maneuver the boat on the marina and to put it back on its place.