Wednesday, October 17, 2018

BENETEAU OCEANIS 46.1: WHAT A PITY!


The hull looks beautiful and the boat is very nice, specially on the performance version (First Line) where it is offered a carbon mast, flat deck genoa furler, German mainsheet system, better sails, adjustable backstay and genoa cars, bowsprit, upgraded performance winches, upgraded halyards and sheets, carbon wheels, lead bulb extra deep keel (2.60m) bigger mast, more 28% sail area and of course single line reefing on a main sail with full battens. Some of the above items standard, most as options. 

They even say that this version “will guarantee unique cruising sensations”. Will that be true, will this boat satisfy the ones that “like fast cruising”, as they say?

If a car manufacturer decides to offer a model with a more sportive version they will have one with more horsepower, lighter and stiffer, with a better suspension and everything that contributes to a more precise and fast car control. A car is not a boat but less weight, more power and more control are three items that will be common when offering a more sportive version, being it a boat or a car.
Is the 46.1 First Line more powerful? No, it is not. One may say that it has a bigger mast and considerably more sail area but that makes it only a boat with more sail area, faster in light wind, but that is not what it is called power in a sailboat.

The amount of sail area on a sailing boat depends on the size of the sails, that can be variable, the power of a sailing boat is the righting moment (that it offers to oppose the force of the wind on the sails) versus the boat weight and shape of the hull (drag).

Well, to be absolutely correct it is probably just a little bit more powerful since the boat will weigh less 159 kg (due to the difference in draft from the standard version) and will have a bit less drag due to a torpedo keel and lead bulb but the RM will be practically the same. They increased the draft and decreased the keel weight and Less weight means also less RM.

Of course, this very small increase in RM (if any) is not proportional to the 28% increase of sail area so what you get is a boat that is faster on light winds (the standard version can also be faster if you use a code 0 or a Geenaker) but that on stronger winds will not be faster and will need to reef much sooner. In fact if you look at the picture below you will see that the boat going upwind in light winds is already at the heeling limit and in need of reefing.
And even if this is a boat with a big form stability it is also one with a small B/D ratio that on the standard version (2.35m) is just 26% (less on the performance version). That means that the boat will sail well upwind and downwind but upwind will not be able to take advantage of the extra power given by bigger ballast, will have to reef sooner and will have a safety stability that probably will not go much further than the minimums required by the RCD.

Regarding boat control the First Line comes without the arch that on the other versions is where the boom control lines are situated. On the “performance” version the control lines are over the cockpit but without a traveler that would allow a better control. I have doubts that if the arch system is well built and well regulated the one over the cockpit will be more efficient due to the much bigger distance between the boom and the pulling point.

They offer a german sheet system, a system that is great for boom control because when the boat is heeled you can work in any of the two winches, the one up or down, but on this case with only 4 winches and no option or possibility of mounting another two, that system will be probably a disadvantage because you will have two winches occupied with the mainsheet another one with the genoa and that means that on one of the tacks the reefing line will not be possible to be handled by a winch at least without taking one of the lines from a winch. Most of the reefing is done by hand but for the final trimming a winch is needed.

And even worse than that, there is the possibility (depending on the tack) that you cannot use a winch to lower the main sail. Yes, for letting it down you will not need a winch but some turns of the halyard around the winch is the way to let it down progressively and in a controllable way. Also, at the end of the reefing process the sail should be tuned pulling the halyard up or pulling the boom down or both.

So quite a mess and much more complicated than with the standard version from wich this running rigging was designed: for the jib on the self tacking system you only have a line, only need a winch and with a furling main you also have only a line for reefing (furling) the main.

On the “performance” version for reefing you will have at least two lines, one for each reef and if you want to have 3 reefs, four lines and it would be impossible to have them all on the same side of the boat. You need more winches to work in an effective way.

I have many doubts regarding stiffness, not in the sense of boat power, but as opposed to bendy, a boat that is rigid while sailing on difficult conditions. The Oceanis 46.1 is built like the other Oceanis: they use a non cored hull with a structural counter mould bonded to the hull, a system that offers a reasonable hull stiffness but weight for weight not one comparable to the one that can be obtained with cored hulls.

And I have doubts due to the boat weight. Looking at it, without ballast, the 46.1 weights 7862 kg. If we compare it with the weight of a main market boat built with better resins (less weight) and  a cored hull using a top infusion technique (less weight) like the much more expensive Grand Soleil 46LC we will see that the weight without ballast is similar (7800kg).

If we compare its weight (without keel) with boats of similar price but with cored hulls, like the Bavaria C45 or the Hanse 458, we will see that they are considerably heavier (8870kg and 8320kg. I do like light boats but I do believe that you can only obtain lighter boats with a similar strength if you use better resins, better building materials or better building techniques or all things put together. It is not the case with the Oceanis 46.1.

The interior looks uninspired and the standard tankage (370L water, 200L diesel) is insufficient (they offer more as option) but what makes me say that it is a pity, is that everybody that sailed the boat have said that it was a well balanced boat and that it sailed well. It could have been a beautiful and great performance sailing boat if many things were different: It has the looks and a good hull.


2 comments:

  1. Hi Paulo,

    Hope all is well! I just wanted to add regarding the HR44, it is actually not built with infusion technique, it is hand layup all the way. If I recall correctly, HR thinks this makes for a higher quality laminate as you have better control of the lamination process. To each their own..

    Regarding righting moment, I don't know if you tried playing around with the calculator on Seldén´s homepage?

    http://www.seldenmast.com/en/services/calculators/rm_calculator.html

    I made a comparison between a HR44 and Xp44 just for fun, using real measured weights from two boats. I know that the calculator is not exact, of course, but it was interesting to see how much higher stability the HR44 has compared to the Xp44. Playing around with the calculator shows that ballast is not as significant to stability as I would have thought. A high displacement seems to have a big effect on stability though.

    Cheers!

    //Thomas

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    Replies
    1. Hi!

      Yes, I knew that the HR uses not infusion techniques but has cored hulls above water line. I bet that it would not take much more time to start using them. If well done and controlled they assure a better and more uniform resin distribution and less resin. I guess I forget.

      Regarding that calculator there are two relevant stability curves the GZ and the RM curve. You obtain RM multiplying displacement by GZ (arm) values. So the displacement of the boat ends to be more important than ballast for static stability.

      The GZ curve curve however is the more important for dynamic stability and also regarding the boat having a good or very good stability curve because it is independent of displacement.

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