Friday, March 21, 2014


Saphier 27
Seascape 27
A first look at the boats, particularly to the large transom of the Seascape 27 would lead many to think that the Saphire 27 is a much narrower boat, and they would be wrong since the max beam of the two boats are very similar, 2.54M for the Seascape and 2.50M to the Saphire. So, this is not a comparison between beamy and narrow boats but a comparison between two types of hulls, one more along traditional lines and the other with all beam pulled back. Both boats come from designers very experienced with these type of hulls, both with winning racing boats, both successful sail racers themselves but while Sam Manuard was (is) mostly a solo racer, Claudio Maletto was a team player at least since he passed from dinghies (1978, world champion in 470) to yacht racing. As an introduction to different types of hulls let's look to a very interesting comparison (pity the Saphire is not there) but we can see the blue shape of the Seascape 27 over other well known fast boats and we can see quite well the differences:

The Seascape and the Saphire also have very different keels and rudders, the Seascape with a twin rudder setup (one on the Saphire) and both with variable draft but using the Seascape a swing keel and the Saphire a lifting torpedo one. Regarding draft the Seascape has 0.85/1.95M and the Saphire 0.40/1.70m. The ballast is very similar respectively, 600kg to 500kg and the Seascape is a bit lighter, 1250kg to 1300kg. The Seascape has not only a bigger draft as also a bigger B/D ratio (48% to 39%) a differences that the more efficient shape of the torpedo keel will not be able to compensate. The beam pulled aft as the superior RM from the hull will give to the Seascape a bigger overall stability.  It carries 45M2 of sail area upwind (with a jib) while the Saphire has 44M2 with a 106% genoa.
Let's have a good look at those two hulls and its differences, particularly in what regards the stern, and its influence on the hull design:

Even with similar beams we can see that the hulls are very different. Some would say that the hull of the the Saphire is like that on account of rating  (it has the shape of most ORC boats) and that the shape of the Seascape is better in what regards performance but more penalized in rating. The results of a test made by, with both boats at the water at the same time, show that is not the case and that both boats (hulls) have advantages and disadvantages in what regards sailing performance.
Not surprisingly the results confirm what I have been observing for years regarding the performance of this type of hulls in racing (real times).

With light winds (5k), even being heavier and having slightly less sail area the Saphire was slightly faster and pointed a bit better. That can surprise many but I have seen similar typed hull boats, for instance the Salona 38, having a very good upwind performance in light winds, better than lighter but bigger stern boats that are faster on most other conditions. That has to do with a smaller wet surface due to a slimmer hull on the transom area. We can see that both boats have a chine but besides the beam all pulled back on the seascape (given to the hull a much more rounded shape) we can see that the chine on the Saphire is higher and will allow much more heel before entering in action. On the Seascape just with a small angle of heel that chine would be on the water, adding hull stability but also increasing drag.

Even so, while on the Saphire it is important to have weight on the bow to raise the stern (and diminish wet surface) on the Seascape it is more important to create heel and put the boat sailing on its chine. It seems a contradiction but it is explained by the difference in hull design and the way these boats with all beam pulled back seat on the water when heeled, being optimized to sail with less drag on an asymmetric optimal waterplan, with some heel. That gives them a bigger LWL and explains the advantage of two rudders (to have always a rudder centered with the waterplan). This difference is fundamental to understand the strong points and weak points of each type of hull. Finot explained those differences on an article some years ago (see drawings on the right).

In what concerns regatta the hull design and the single ruder of the Saphire gives it an advantage regarding not only maneuverability but also the acceleration out of a tack. Still regarding steering the one of the Saphire is more informative while the one of the Seascape is completely neutral. That neutrality is less rewarding while steering manually but it is an advantage while the boat is on autopilot, making it easier to control. These relates to the differences between the designers that have a reflex on the boat: the Saphier a better regatta boat, the Seascape a better short crew and offshore boat, not only by its superior overal stability but by the the superior easiness of control and less roll limited by the transom design that not surprisingly is the type of transom that we find on solo racers.
With a stronger winds (12/15K) the two boats go upwind at the same speed and  with the same pointing ability. Maybe in what regards pointing ability the superior draft (1.95 to 1.70m) of the Seascape is compensating what seems to be the better upwind potential of the Saphier hull. Anyway equal performance for both boats at least in flat water. Probably with waves the Seascape would be more slowed by a bigger wave drag and the Saphier would be faster, at least with 15K since this is the limit for the Saphire in what regards reefing. with higher winds the superior form stability and higher B/D ratio (that makes the Seascape a more powerful and stiff boat) could somehow compensate that drag disadvantage, passing the waves with more power (and less comfort). They did not had more than 15K winds but the impression they got was that the stronger the wind, the better the Seascape seems to go.

Saphier 27

They say that under geenaker the boats go at the same speed but don't say if it is downwind or at a beam reach. I assume it is on both situations but it seems clear to me that with higher winds, specially on a beam reach the Seascape would be faster since it is a more powerful boat and can maintain all sail up with more wind. Downwind with a spi in absolute terms it is hard to say but it is clear that the Seascape would be a much easier boat to sail fast even solo or with a small crew while the Saphire will require an experienced crew and a careful handling of sails and crew weight distribution.

Seascape 27
In what regards performance cruising and for all practical effects the Seascape would be a much faster boat downwind, just because it is much easier to sail it fast. The overall stability and easiness of use makes the Seascape a best offshore boat (not protected waters) and a better overall coastal cruiser in what sailing is regarded. In what regards accommodations they are a bit spartan on both boats but enough for a sportive kind of coastal cruising or for a week end with the family. Anyway regarding the interior you can see for yourself. In what concerns basic price the Seascape on the Standard version is about 20% more expensive, probably because of its hydraulic swing keel but that can be different after all extras are summed and that difference can eventually be smaller. The Seascape basic price is 63 900 euros and the one from the Saphire 49 000 euros.

Michael Tobler :
Just a quick update on the ORC weights for Saphire No 4: 1428kg and Seascape No 7: 1540kg. For the measurement they need to be equipped in the same way with engines, but without sails. As you know, overall weight has a big Impact on the stability of the boats. Unfortunately, there was only Little wind during the comparison and it will be a pleasure to see the two boats racing in strong winds.

Thanks Michael!
Congratulations for your lovely boat and the European boat of the year award. I saw it in Dusseldorf and it just looked great. Just for the record the weights I have mentioned were the weights stated by the builders, 1250kg for the Seascape and 1300kg for the Saphire 27. I believe by what you say that the boats were weighted before the test sail so the clarification his here. It seems that all of a sudden the "lighter" boat becomes the heavier boat ;-)

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