Thursday, October 17, 2019

SUN FAST 3300 BEAUTIFUL AND FAST


This year was a great year in what regards fast small racer-cruisers, boats that are more used to race than to cruise and one of them was the Sunfast 3300.

The new boat is faster than the previous one (3200) but it has needed some adjustments: it has received bigger rudders and to be competitive in solo/duo sailing, water ballast (it seems that the WB system still needs some improvements).

Its racing career on the big classics started well on the Spi-Ouest (two handed) being 2nd, in compensated and real time behind a JPK 10.80 but beating its rival, the JPK 10.30 that won one of the races but was handicapped by problems due to lack of tuning (the boat was launched just some days before).   

Anyway the Spi Ouest was this year raced on atypical conditions with weak winds, being some races cancelled due to lack of it.

JPK 10.30
Then the 3300 was beaten by the 10.30 on the Fastnet and on the Quadra Solo/duo Med. 

On the Quadra Solo/Duo they have not competed on the same class, the JPK 10.30 won the solo division and the Sun Fast 3300 was beaten on the duo division by a JPK 10.10 (the model the JPK 10.30 replaced) but I would say mostly due to the inconsistency of the results on the several legs.

The next big battle between the two in major races will be on the Middle Sea Race  where we will see two very good teams racing them, the 10.30 skippered by Laurent Camprubi and the 3300 by Mallaret. The Middle Sea Race starts next Saturday and I will be following it.

 Lots of interesting sailboats racing this edition. Besides these  two we will have a very well sailed Grand Soleil 34, a MMW33 and several JPK and Sun Fast as well as many Jboats, but unfortunately not the new 99, that seems to be a step behind the new JPK and the new Sun Fast in what concerns performance.

 It is going to be interesting to see how fast performance cats, used almost exclusively for racing (and that do the Fastnet) will perform on the med waters and this year the conditions will be Med typical, lots of upwind sailing, weak winds and strong ones will be met.

 And on on the two handed division how the Pogos 36 will perform against the JPK 10.80/Sunfast 3600 and the Pogo 12.50 against a J122.

 Without doubt the Sun Fast 3300 is a great sailboat, faster than its predecessor the 3200 and faster than the JPK 10.10. The only problem for the Sun Fast 3300 is the JPK 10.30 that seems to be just a bit faster overall and has a better handicap.
The JPK 10.30 interieur

It is yet too soon to make a definitive evaluation because the races where the two boats raced together, with top crews, are few. It is yet to be seen if the JPK 10.30 will leave the Sun Fast 3300 on its shadow, the same way the JPK 10.10 has done with the Sun fast 3200 (that nonetheless is a great sailboat too).

It remains to be said that while both boats have interiors mostly thought for ocean racing the one of the JPK is nicer and more adapted to cruising and many racers like to do some summer coastal cruising with the family.


Tuesday, October 8, 2019

SWAN 48 THE PERFECT PERFORMANCE CRUISER?


The Swan 48 is on the water, we have photos, videos and also the technical characteristics. It is time for another post, even before seeing it in Dusseldorf, because this is a very interesting yacht and probably will be one of the most popular on the long Swan history.

The last time I checked they had already sold 24 (only 3 built) and I bet that the sales will increase after the possibility to see and sail the boat. In fact the Swan 48 looks even better on the water than on the drawings and after having a look at the interior, hull, cockpit and the technical data I find very little to criticize.

The interior looks just fine to me. They resisted the modern tendency to turn all the available space to the interior, to make it bigger, at the cost of storage space. No, in what I am concerned the layout of this yacht is perfect, it has even space for a 2.50 m dinghy on a garage as well as a considerably sized sail locker as well as lockers under the cockpit seats.

The galley is good, the saloon has enough space and the quality of the design and materials, typical on Swan, will make it a lovely space. The cabins without being king size have an adequate dimension and I would say that the forward one is large offering big storage and a a head with a separate shower with adequate dimensions.

The two aft cabins are smaller being one of them bigger than the other and offering two individual beds. The storage there is not much unless one opts for the alternative layout that offers a folding berth on the smaller cabin and a lot more storage.

For the ones that do extensive cruising this layout makes a lot more sense and that way the boat will have two cabins and two heads being perfect for two couples to cruise. When the kids come to visit they can find sleeping space on the folding berth and on the saloon.

On the first post I said I did not like the single rudder. They have considered that possibility while designing the boat but had opted for a two rudder set up that has many advantages over a single one in what cruising concerns and only a disadvantage: a less effective control at slow speed at the marina for reasons I have already explained (there is a post about it). But because this yacht will have a bowthruster that is really not a problem.
Above Swan 48, below Solaris 50

I can only find three things I don't like, one of then unfortunately has become the rule on luxury yachts. I mean the electric captive winch technology linked to a single point main sheet system. Everything is operated by a joystick, the winch is below deck and I doubt that it has a manual override.

That is a great way to simplify the deck layout that will need only more 4 winches instead of 6 and allows for an easy operation. I would say that it is an indispensable system on big yachts sailed without a big crew. The forces are huge and the system has been used already for some years (Harken and Lewmar) with success.
Solaris 50

But on a performance cruiser with 48ft? On a mainsail with 77.1m2? The system will rely entirely on electric power and on a generator. A generator makes sense on this type of boat where it is expected to have AC, but excludes the possibility of having a traveler for the main that even if  not essential for cruising will certainly contribute for the pleasure of sailing.

Solaris 50
Sailors that like to sail love to have their sails perfectly trimmed, it is not about the speed (many times only some extra decimals of a knot) it is for the pleasure of doing it. That is what performance sailing is about and a performance cruiser should offer the means to do that specially on a boat with less than 50ft were the efforts are manageable by a single sailor.

The second thing I don't like, and this one seems to me absurd, is the mainsheet going through two holes on the back of the cockpit table (look at the 2nd foto). The efforts on the system will be considerably bigger due to friction and the lateral efforts at the base will be huge. It makes no sense and it looks odd and poorly designed.

The 3rd one has to do with the windlass position and the two opening hatches of the forward chain locker/sail storage space. The winch is on the side and I don't think that is the problem, but one of the hatches, near the winch effectively restricts winch operation specially if something goes wrong and you need more space than the little one that is provided to operate it. The problem would be solved with a bigger single hatch opening to the opposite side of the winch.

Very little for a boat that seems very well balanced and designed. For reference we will look at the numbers comparing them with the ones of the Solaris 47 and Solaris 50, probably the closest competition for this boat that should cost just about a million euros, not far but probably a bit more than the Solaris 50.

All measures on metric system (m, kg)

LWL: SW48-13.88, SO47-13.40, SO50-14.25; Beam: SW48-4.59, SO47-4.36, SO50-4.55; Dipsplacement : SW48-15000, SO47-12600, SO50-14200, Standard Draft (all with a similar type of torpedo keel): SW48-2.40, SO47-2.80, SO50-2.80; B/D : SW48-35%, SO47-34%, SO50-35%.
Regarding the keel it is worth noting that the superior draft of the Solaris will mean that for an identical B/D it will offer more righting moment.

Solaris 47
Regarding the hull we can see that the Swan, that looks to be less beamier than the Solaris, is in fact more. What gives that impression is that while all the beam on the Solaris is pulled back, that is not the case on the Swan. This means that the Solaris will roll less downwind, being easier to be driven fast on autopilot and that the Swan (if all other things are equal) will offer probably a better performance upwind and in light winds.

The Swan has  a two rudder system and both Solaris a single rudder. I think that for cruising a two rudder system is preferable but probably for this type and size of hull, in what regards performance, a single rudder is marginally better. Not the case with extreme beams, like for instance Pogo 50 (5.15) but the case of most TP52 (max beam 4.43).

SA/D : SW48-23.4, SO47-24.2, SO50-27.8; D/L : SW48-155.8, SO47-146.0, SO50-136.1. This means that the Solaris, especially the 50, is proportionally lighter and also that proportionally to the weight they have more sail area. That would make the Solaris faster in almost all conditions even if it is not a huge difference. I would not be surprised if upwind with medium to strong winds the Swan is faster.



All great sailboats, very similar in what they offer and on the style of cruising they provide and even if neither of them is a cruiser-racer, if well crewed, they would not look bad on any race. The Swan offers a prestige that the Solaris still aims to reach, due to decades of success, but I would say that if the Solaris continues on the same trend some day it will reach a similar status.



Personally I would say that I like more the hull design of the Solaris and also its deck and cabin design but I would prefer the Swan 48 interior. The one from the Solaris looks a bit impersonal and even in what regards the Swan I am judging only by photos and videos and assuming it has the same quality of the 54, it looks warm and cozy.



Of course I am talking mostly about style and regarding that the tastes can be very different but if I had to chose between the Swan 48 and the Solaris 50, well, it would not be an easy choice and probably I would want to sail both boats to decide.

Saturday, October 5, 2019

THE NEW VENDEE GLOBE FLYING RACERS


While the mini Transat is just beginning, let’s have a look at the incredible new IMOCAS that will race the Vendee Globe. This edition will be specially interesting because not only the number of new boats is big (8) but also the number of Naval Architects that designed them is considerable (4).

 Unlike on the last edition, where most of the new boats were designed by Guillaume Verdier, this year he will have only two new boats racing (Apivia et aDvens) while Juan Kouyoumdjian will have also two (Arkéa-Paprec and Corum), VPLP will have three ( Charal, Hugo Boss, DMG-Mori) and Sam Manuard will have L’Occitane. 



Sam Manuard is the least known and also the one with a smaller cabinet but you will remember him if I say that he was the designer of the Seascape 27 (today First 27) and more important, the designer of many recent winning boats on the class 40. He is also a good solo/duo racing sailor.

And to make things even more interesting the new boats are very different regarding design and foils. Some are designed to fly high on the water like VPLP designs, narrower boats and designed to have a minimum drag while flying, sailing with little heel.



The designs of Verdier are quite the opposite, quick to raise the bow out of the water but not designed to fly high. He bets on a superior stability given by beamier hulls that provide a big lateral support to the boat. 

For diminishing wet area, their boats are designed to sail with a considerable heel. The approach of JK is an intermediate one with beamy hulls needing heel for the righting moment but with a foil design that allows the boat to go higher on the water, as we can see on spectacular images of Arkéa-Prapec. 



And the surprise may well come from Sam Manuard that says his boat will be very different from the others and from Sam good things are to be expected. He does not have the same experience regarding foils but he is working with Nat Shever the one who designed the foils on the winning boat on the America’s Cup and who is working now on American Magic. 

Regarding the rules of the last edition there is a change that brought a huge evolution: now it is possible to modify the angle of the foils but Michel Desjoyeaux, the double winner of the race and today involved in boat design, says that the boats will be unbalanced without foils on the rudders (that are not allowed).



The IMOCAs, in what regards foiling, have only 2 support points, keel and foil and are inherently unstable having the need to have a bit of the transom on the water for support. We can see on the Hugo Boss video that  when it goes higher and lifts the transom out of the water instability follows and the boat falls backwards due to lack of support.

It seems obvious that the boats to continue to evolve need lateral foils on the rudders, but it don’t seem probable the rules to be changed before the Vendee Globe.




Regarding the performance of the new boats versus the last generation ones, Lauriot-Prévost (from VPLP) says that Charal can foil with 13Kt of wind and that, while older boats with 16Kt wind could do 22/25kt, the new ones can go at 26/30kt.

When the boat starts to foil it will win 4kt speed. This means that the angles that they will choose to sail will be different depending from boat to boat and the wind needed to foil. Everybody will be looking for conditions to foil even if that means a slight detour that will be more than covered by the extra speed.



A difference of 96 NM each 24 hours is a huge difference and certainly means that, if they don’t break, one of the new boats will win the Vendee, but it is not sure that they will not break, specially the foils.

 The foils are now much bigger and the forces on them increased a lot. And if they break probably the high flyers, the boats from VPLP, will be the ones that will see their performance more compromised: they are narrower, with less righting moment and specifically designed to fly.



Maybe Guillaume Verdier and JK are counting that the chances of a boat to do the entire race without breaking a foil are slim and are not handicapping so much their boats in what regards sailing without foils.

 Also big foils, like the ones of the VPLP designs, cannot be lifted on any considerable extension and therefore in light winds they make the boat slower due to more drag. Not that on the Vendee there is a lot of light wind but they will find it on the Doldrums, that they will pass twice and there a considerable difference of speed can be very important.



Foils will probably be the key element of the race. It will be a fight between more lift and more drag (flying boats) versus less lift and less drag, this in what regards the drag from the foils because the superior drag from the foil can be compensated by the smaller drag of a boat flying. Probably, if the design is equally good, foils with less drag will tend to break less than foils that offer more lift (and drag). All very complicated and interesting.

One thing is for sure, this will be a great race and one not only among sailors but also among designers, kind of race that makes yacht design progress, my kind of race.😉



Wednesday, September 18, 2019

DEHLER 30 OD AND JPK 10.30 - FIRST MOVIES


A lot can be learned regarding how a sailboat sails looking at a good movie. Not the same thing as sailing the boat but worth commenting. And let's not forget that comparing two fast boats in what regards sail performance, sailing both boats, but not having both in the water at the same time, can be very misleading.

The real test in what regards true performance and handicap performance can only be given on the race course and not any race but on the main ones, that have good racing crews, where we can be sure that there is a good possibility that the boats are being sailed close to their potential, specially if there are several competing.



The Dehler 30OD is on the water but not for so long as the JPK 10.30 and has not yet been raced in a major race, unlike the JPK 10.30, that won its class on the last Fastnet, being really fast on the water.

In real time it was only about half an hour slower than the fastest XP44 (3 days 2 hours 47 minutes), faster than the fastest Jboat racing, a J133 (and they were many with several models) and faster than the fastest Grand Soleil 43.

The results on the Fastnet are even more impressive if we consider that all the other boats I mentioned were sailed by a full crew while the JPK 10.30 was sailed by a duo, being one of them the builder of the boat. Of course they also won the two handed division, leaving the second, a brand new  Sunfast 3300, at more than 4 hours in real time and almost 5 in compensated.



I have no doubt that the JPK 10.30 is a great design and that it will be a winner of many races. Let's wait for the racing results of the Dehler, in real time and in handicap to see what its real performance is.


Regarding the movies the JPK looks perfectly balanced while it seems to me that the Dehler buries too much the bow on the water and that's curious because, looking at the bow shape, the one of the Dehler seems more modern, but of course the buoyancy of the forward sections and the longitudinal CG are more important.


The Dehler seems to have very narrow entries and very narrow forward sections and has a big beam with all the beam pulled aft. Such a design needs to have a lot of buoyancy at  the bow. Compare its design with the one of the Pogo 30 and you will see what I mean.


Friday, September 6, 2019

Tuesday, August 13, 2019

"FAST AND FURIOUS"?


“Fast and Furious: the incredible rise of the cruising catamarans”. That was the name of an article on a Yachting World magazine about the increasing number of catamarans. Besides implying that generally catamarans are in what regards cruising a faster option “offering better speed”, they say also that it is like “having an upgrade”, that cats are getting “bolder and sleeker”IS THIS TRUE? 

Above the old Outremer 45, below, the new one
Sailing 5 months a year on the Med I have seen the huge increase on cats, specially on the charter fleets, but they are not certainly becoming sleeker, quite the opposite and they don’t seem to have anything to do with sailing fast, not even with sailing since they motor most of the time.

Fast and furious certainly does not apply to the vast majority of new cruising cats being sold: Lagoons, Fountain Pajot and Leopards. Those, while offering a huge interior space and apartment like interiors, do not offer sportive cruising or a good sail performance, specially in lighter winds or upwind. 

While being a good option for sailing on the trade winds they are a lousy option for Mediterranean or Baltic sailing, due to the variable winds with a good share of weak winds and lots of upwind sailing. 
Above the old Outremer 45, below, the new one

Of course there are sportive cats that offer a sportive performance but even if their number is increasing they are a very, very small percentage of the number of cats sold and remain marginal.

As the builders of Ice 61 say “the angle going to winward is almost like a monohull (+30º)” but that is on a very sportive cat with carbon foils and low windage hull and cabin. This is probably true in what regards performance cats with daggerboards or foils on the market, being the two best sellers Outremer and Catana. 

But if you have a look at their catalogue you are going to see that the smallest Outremer is a 45ft boat and even if Catana has still a 42 the next boat is a 47ft and I will say that soon we will see Catana range to start at 44/45ft.

Above the old Outremer 45, below, the new one
Why is that? Catamarans offer much more interior space than monohulls and sportive brands of monohulls like Pogo, X yachts, Grand Soleil, JPK or RM start their range of offshore performance cruisers at around 30/33ft, so, having the catamarans size by size much more interior space why performance catamarans start their range at about 45ft, many of them at 50ft?

Yes, in what space is concerned it would make a lot of sense to start their range of offshore boats at least at the same size as monohull performance cruisers, but not in what regards seaworthiness and stability.

That’s because sportive monohulls have a considerably better stability curve than mass production sailboats, having a much lower CG (they have a bigger B/D, more draft and the ballast on a torpedo at the end of the keel) while with sportive catamarans it is the opposite, they have a lot less stability, size by size than condocats.

Above, old 40ft Fountain Pajot, below, the new one
Sure, sportive cats have a slightly better CG than condocats but since they don’t have ballast the difference in what regards the CG is nowhere close to the difference between sportive cruising monohulls and similarly sized mass production cruisers. 

Cruising catamarans have obvious limitations in significantly lowering the CG so and to increase stability they have to increase beam or weight. 

Condocats like Lagoon or Fountain Pajot are heavy and the weight is a fundamental factor on their stability. They are also designed maximizing interior space so their windage is huge, they don’t have foils and the performance upwind is lousy. 

Comparing to my boat (Comet 41s) I would say more 15 to 20º upwind angle and a slower speed. Years ago, sailing side by side with a Lagoon 400 with optimum wind for the Lagoon (about 17k) I could see that while beam reaching I was just slightly faster (both boats over 9kt on GPS) when we turned upwind in 8nm I won about an hour. 

There is a famous video where on an “ upwind race” a slow heavy Amel beat a fast performance cruising cat. The Amel is known to have a bad performance upwind while the Lerouge designed performance catamaran, even if not with foils (that Lerouge consider that don’t make much sense for cruising), is a low windage light fast boat with a much better performance upwind than any condocat.



Performance cruising catamarans with daggerboards are better upwind and even if they cannot beat on that point of sail a performance cruiser they are faster on all other points of sailing, except with weak winds. 

On the Fastnet, cruiser racers cats prepared for racing are racing it for several editions and, if we look at the results over the last years and compare them with similarly sized monohull cruiser racers, we will see that in some years the cats are faster in others it is the other way around, depending on the wind and sea conditions.

On slow editions with more upwind sailing and lighter winds the cruiser racer monohulls are faster; on fast editions with stronger winds, lots of beam reaching and downwind sailing it’s the other way around.



But cruiser racer catamarans don’t show up on the big Med Classic, the Middle Sea Race and I believe with a good reason: the weak winds coupled with lots of beating on the two first legs would not compensate the advantage they would have on the final leg, beam reaching and downwind sailing, but I would love to see them racing there as I love to see them racing everywhere.

Above, old 40ft Fountain Pajot, below, the new one
On the Caribbean 600 they are faster than monohulls since it is a beam reaching and downwind race as well as on a Transat or any race on the trade winds but if we look at the ARC we are going to see that size by size they are as fast as performance monohulls of the same size and I have been looking at that for years.Why?

Because even if racing the crews there are mostly cruising crews or amateur racers and while a monohull performance cruiser can be sailed at full blast without safety concerns other than an occasional broach, on a performance catamaran, if the boat is sailed near the limit there is no space for mistake and that demands a very professional racing crew.

On the ARC, the very few cases I have seen performance catamarans sailed at the limit by big professional racing crews they were going faster but on almost all cases, with amateur cruising /racer crews, they go at the same pace as fast monohull performance cruisers, many times slower.

Performance cruising catamarans while being a very good option in what regards sailing and interior space have however a major inconvenience for most: size ad price. The two things are related because to have a great performance they have to be light and the only way to give them a safe stability for cruising is to increase beam and that means for the same stability of a condocat a much bigger performance cruising catamaran and of course, a bigger boat is much more expensive.

It is not by accident that Outremer starts its range at 45ft and that is certainly not because a smaller catamaran would not have more than enough space for a couple, but because performance catamarans have to be big to offer a good safety stability for cruising.

Above, old 40ft Fountain Pajot, below, the new one
If we look at the edition of Yachting World where they associate fast and furious to the incredible increase on the rise of cruising catamarans we are going to see that the average size of the models they refer as “fast bluewater cruisers” is 54ft and that the average prize is way more than 1.5 million euros.

Out of charter, extensive cruising is made basically by couples that can have occasionally another couple sailing with them and for those the size of a 54ft catamaran, exceeds in much their needs for living space and makes the price unnecessarily much higher than the one of a monohull adapted to that sort of cruising, with an adequate level of safety, I would say a boat between 40 and 45ft.

The handling of a 54ft powerful catamaran can also be a lot more complicated than the one of a 40/45ft monohull specially on the Mediterranean where near the coast one can expect huge gusts that can be 3 or 4 times bigger than the average wind.

But even if the costs of maintenance, marinas and ports are much higher, if the boat is used as a permanent living accommodation then a 50 to 55ft catamaran can make all the sense for the ones that have the money to cope with. A much superior area for the use of solar panels can give the boat all the autonomy it needs to stay on anchor and the dinghy storage they provide allows for an easy deployment making live easier.

However I believe that the association of the increase of catamaran sales and their performance is a misleading one: the catamarans that are increasing in numbers are mostly condocats, on the charter and on the cruising market and they are sold not for their performance but for the apartment type of space they offer and for the size of it.



The statement that cats are getting “bolder and sleeker” is also not true unless they are referring to the increase of weight, the increase of the living space and to the increase of windage. If we compare an older Outremer with a new one and do the same with a Fountain Pajot it will be evident that the new boats are heavier and have a much bigger windage. They also have a much bigger living space and that is the true reason for the increase of catamaran sales.


I cannot resist to mention that I see many if not most of those charter catamarans motoring while there are perfect conditions for sailing. I believe that a percentage of the ones that charter them don’t even know how to sail and chart them as a less expensive motor yacht, with two engines, plenty of interior space and a nice big outside covered cockpit: a moving condo.

Would I have a catamaran if I had the money for it? Well, maybe but surely not for the extra space but for the fun of the speed downwind, something like the SIG 45 even if that one is a bit on the danger zone in what regards cruising with a couple.

I certainly would prefer a trimaran, maybe the new Dragonfly 40, but for the money they cost I have many doubts I would not find a fast monohull that I would find more appealing.



Even if I had the money it would be out of question because my wife does not want to hear about it: The SIG 45 because she finds it dangerous and the Dragonfly because it has a small interior. She would settle for a condocat but then it is me that would not be interested: no fun sailing it.

Saturday, May 11, 2019

PLEASE, A RCD CERTIFICATION FOR BLUEWATER SAILING BOATS!



I am closing the blog for sailing and I will get back to my sailing chair somewhere in October but in the meantime I will like to offer you all a last post that I hope will contribute for a better information about boat safety stability and the RCD class A certification. Something that gives food for thought and eventually contributes to the implementation of a bluewater RCD certification class. 
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When the RCD was being drafted they invited naval architects and naval engineers from several nations to contribute with studies and thoughts regarding yacht stability, including safety and final stability.

The general consensus regarding an offshore boat, what the Americans call a bluewater boat, was that it should have an AVS of about 130º and the correspondent final stability.

There is logic in what regards that number. There are studies that indicate that the average time for a boat with an AVS of 120º to re-right itself on the same sea conditions that lead to an inversion is between one and two minutes.

But things are not that simple because if the boat is inverted by a rough much bigger wave, that time can be much, much bigger and if one is on the cockpit at the steering wheel, even if attached to the boat, things can get ugly even with a one minute period.

So, taking all that discussion into consideration ,what is the AVS that is considered minimum to a class A boat to pass the RCD certification? Yes, the 130º value was considered but it is a maximum value that comes in a formula, this one: 130 - 0,002m) but always ≥ 100°, being m the boat mass

That means that a yacht with a small mass, a small boat, will need an AVS not very far from 130º but it also means that on a considerably bigger boat the AVS can be close to 100º.

And, of course, increasing ballast to better the AVS creates more RM and more efforts on the boat hull and structure making the boat more expensive.

The result is that mass production builders tend to follow the RCD minimum requirements in what regards AVS opting for one slightly above the one that formula gives as minimum. More expensive boats usually opt for having a higher AVS (having a bigger B/D) one considerably above the minimum that is determined by the rule for Class A, normally near 120º but rarely 130º or over 130º.

Pogo 12.50
Sadly, due to lack of awareness of the public, some of the brands that make more expensive boats, like Wauquiez (Pilot Saloon) or Amel have abandoned that practice and come close to the one followed by the cheaper mass production boats, having an AVS not far from the minimum that is required for the Class A certification of the boat.

More expensive boats are made to a budget too and some are choosing to spend all the extra money on an even more luxurious interior and I would say with very good market results, but misleading sailors that assume that those boats have a better stability and seaworthiness than mass market boats.

Some examples to make clear the variation of the minimum AVS required (for certification on class A) with the boat mass : A Pogo 30 will need a 124.4º AVS, an Oceanis 41.1 an AVS of 114.3, an Oceanis 46.1 needs a 108.8 AVS and an Amel 50 needs only one AVS bigger than 100º (these values are approximate).

Elan Impression 444
This will allow Amel to say that an AVS of 110º (or so) is vastly above what is demanded for the certification of the boat as Class A, giving the impression that the yacht has a very good final stability and a very good AVS when in reality it is an average one and a poor one for a bluewater boat, if we take as measure those 130º that were considered on those studies as the value indicated for a bluewater boat.

And if we look at the B/D of the two Oceanis, both the smaller and the bigger one, we will see that with similar keels and not very different drafts (2.19, 2.35m), the smaller one needs a B/D of 29% while the bigger one only needs 25% to be slightly above the required AVS for the class A certification, meaning that the smaller boat has probably an AVS superior to the bigger one and I say probably because for good reason brands like Beneteau or Amel don’t make public the stability data of their boats.

Hallberg Rassy 44
Note that the same stability safety reasons that lead to consider necessary an AVS not far away from 130º on smaller yachts are not less valid on bigger ones even if RCD gives a different impression.

The only thing that changes is the bigger risk of being rolled by a wave on a smaller yacht (because the overall stability is smaller) meaning that a bigger boat will need a bigger breaking wave to be rolled. Not so much in what regards a knockdown by a bigger gust of wind or by one of the increasingly more frequent weird meteorological phenomena, since the sail area is proportional to the boat mass.

But I do know of several 40 to 45 (some bigger) yachts inverted by waves, numerous cases of yachts that were knocked down and a considerable number that were abandoned after several knockdowns.

I am sure that some will be asking themselves what has the AVS to do with knock downs? Or even with an inverted boat?

A lot, because a high AVS implies a big safety stability, meaning that not only the boat would be much harder to knock down as it will recover much faster from one and that is vitally important, because when a boat lies flat on the water has very few remaining positive stability and it will be at the mercy of the next wave.

That’s why most boats that are rolled are not by a single wave but by a set of two: the first one takes out the boat stability (knocking it out) the second one rolls the yacht.

An higher AVS means also that the area under the positive stability (on a RM curve) is much bigger, several times bigger, than the one over the negative stability, meaning that a much smaller wave than the one that had it inverted, can bring the boat back.

If the positive area of the curve is 4 times bigger, it means that for bringing the boat back, from an inverted position, you will need a wave 4 times smaller than the one that inverted it. If the positive area is only two times bigger that means that you will need, to re-right the boat, a wave half the size the one that inverted it and that, if the boat was inverted by a rough wave, it can be a problem.

Najad 450 cc
While a small 33 ft light yacht (that to be certified as class A has to have a better AVS than the one of a bigger boat) will recover very quickly from a knock down, the typical 45 mass production yacht (that can be certified with a much lower AVS) will take much more time and in some cases the water on the sails can even prevent it to right up on any reasonable period of time, leaving it exposed to the waves with little stability remaining.

We can conclude that the Class A certification, as a measure of the boat stability and seaworthiness, is useful in what regards 30/33 ft boats and gives information about a more or less seaworthy boat (for instance, separating the Oceanis 30.1, that does not have the stability to be a class A, from the Hanse 315, that has), but it will say nothing about the seaworthiness differences (in what concerns stability) between an Oceanis 41.1 and an Hallberg Rassy 412: they are both class A boats (by a big margin) even if they are very different in what regards final stability and AVS.

Elan impression 394
And since the RCD main objective is to certificate products providing the public with information regarding their safety and conditions where they are safe to be used, it is obvious that in what regards boats over 36ft it fails miserably since they are almost all class A boats, giving the impression that they are equally suited for offshore, bluewater sailing.

Of course, the ones that gain with this situation are big mass production builders that want to make boats adapted to most users, the ones that will never sail in bad weather, boats with a smaller stability and AVS but with a certification that will put them on the same class of boats designed to be much more seaworthy and designed to be sailed on more demanding weather.

That is clearly a commercial advantage but it neither allows transparency in what regards sailboat characteristics and the market nor provides consumers with accurate information. I have to say that sail magazines have done nothing in what regards making clear this distinction between yachts with different final stability, negative stability and AVS.

That distinction cannot be evaluated on a test sail, that is rarely done in bad weather, much less with a knock down or inverted boat, but that difference results very clear when comparing stability curves. Magazines used to publish them but mysteriously stopped doing that. And even when they published them they never commented, specially if they revealed a poor AVS, final stability or a big negative stability.

It is ridiculous that the higher seaworthiness certification is today achieved by almost all cruising boats over 30ft. Should not the consumer who wants a much more seaworthy boat than a 30ft have the right to clear information about that?

That will only be possible creating a new higher seaworthiness and stability specifications class, one that will allow consumers to distinguish between boats like an Oceanis 41.1 and Halberg Rassy 412 and that will separate boats that can be sailed offshore from the ones that are designed to be sailed offshore, bluewater boats.

There have been talks about that for a long time but I don’t see any will to pass that to the law since big boatbuilders are completely against that new class, for obvious reasons, that have nothing to do with transparency, information and public interest.

Hunter Legend 50
There are more factors on the RCD in what regards seaworthiness and stability, like the minimum energy at 90º, the downflooding angle and the STIX but they are secondary to AVS, final stability and negative stability. Sure, the minimum energy at 90º is very important but it is directly related to the AVS (since the types of hulls today are very similar), the downflooding angle is very important and should be considered but it is easily improved and does not depend on the basic stability of the sailboat while the STIX only gives a general idea of the boat overall stability, not final stability and it has a factor that can count very negatively without reason, I am referring to the boat sail area, as if the sails could not be easily reefed.

For the ones that think that I am exaggerating let me remind you that the IMOCA are self-rightening. We could say that they are designed to be sailed on the southern seas and the worst seas on the planet but that is not the case with the 40 class that are meant to be ocean racers.

On the 40 class box rule it is not only demanded that the boat pass the stability criteria to be approved as a class A boat but to ” proving that the boat is capable of righting itself from the broached position with empty ballast tanks.
It must be when heeled at 90 degrees … the boat in measurement trim is kept in this position with the aid of a strop passed around the mast at the level of the measurement band at the top point of the mast ... the load exerted on the strop must be a minimum of 235 kg and a maximum of 320 kg.”

This on a boat with a displacement of a bit more than 4000 kg and a mast of around 20m means a huge RM at 90º. On a cruising boat that weights 2, 3 or 4 times more that value should be 2, 3 or 4 times more. Those values for the 40 class boats are so big that give most of them the ability to be self-righting (using the water ballast).

Hanse 430
These values of RM at 90º are not only measured on the water (and not on the paper) but also are several times bigger than the ones that result from the stability curves needed to certify a yacht in Class A.

Should not a cruising boat meant to be sailed bluewater have at least similar final stability values, the ones that warrant that the yacht is capable of righting itself quickly from a broached position? Should not consumers that want to buy a bluewater boat have accurate information about this? Is it not for that that the RCD exists?

Certainly they are not being informed now, since the RCD allows yachts to be certified in Class A with an AVS just a little bit over 100º and such a boat in sailing trim, with sails on the water, would not be able to right itself from a broached position on a short period of time, staying there, knocked down, almost without positive stability at the mercy of the waves.

A new RCD category for bluewater boats, against the will of mass production builders, will only happen if there is enough public pressure and for that sailors have to be informed and aware of what is going on.
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A request to you all, I am sailing and I will not post this on any sailing forum or on facebook groups. If you agree with what it is said please contribute to the discussion on this topic, not only here but on the internet sites where you discuss sailing information. You are welcome to share this post where you find it useful.

For the ones that want to follow my personal sail log I do that on my facebook page. I am already sailing and having fun even if it is yet a bit cold this year on Macedónia, North of Greece. You can still see the snow on the top of the mountains.
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