Daggerboards or fixed fin keels?

We understand why some shipyards have opted for fixed fin keels. As their priority is comfort - with considerable equipment on board which increases displacement, the keels are the obvious solution for these catamarans.

It is clear that daggerboards require more work than fixed keels, so it makes sense that catamarans that are not looking for performance would opt for the fixed keels, but they do not belong on board a high performance catamarans. No serious naval architect would claim that fixed keels deliver better performance than daggerboards across the spectrum of wind and sea conditions.

Daggerboards allow better performance upwind: pointing a few degrees higher and suffering less leeway. Even a few degrees gained represent a significant distance after a few hours of upwind work, whilst downwind - raised daggerboards present less wetted surface than fixed keels.

Not only do daggerboards allow for better performance, they also constitute a safety feature in rough sea conditions. In heavy beam seas, a catamaran with its raised daggerboards will slide down the waves much easier than a catamaran fitted with fixed fin keels.

Curved foils?

We considered curved foiled but concluded that, most of the time, even on a light 9 ton high performance catamaran, they would not be as efficient as high aspect ratio straight daggerboards.

Our hydrodynamic research shows that only above 22-25 knots boat speed would the curved daggerboard bring additional performance, and while the BAÑULS 60 #1 has already sailed at 30 knots boat speed, this unfortunately will not be the case most of time, so the additional cost of curved foils is prohibitive for little or no gain. We prefer to invest the money in real performance enhancing features.

The option could be considered on a drastically lighter racing version - being a full stripped out racer.

While we have designed the BAÑULS with lots of inspiration from the racing world, we believe that the curved foils do not belong on board any 60ft cruising cat but only on board a stripped out racing machine like the 105ft Maxi trimaran Sodebo.


As we target performance with safety and easy handling, we opted for asymetrical daggerboards with a shorter length. The aspect-ratio of the boards is still high enough for the asymetrical section to increase lift, allowing us to reduce its surface area without any loss of performance or leeway.

Shorter daggerboards are safer as the boat won't fly a hull at low-medium wind speed.

Shorter length means lower cost, lower weight and less loading in the daggerboard casing, therefore less reinforcement and less weight. Less weight leads to increased performance and an easier handling of the boards.

Carbon fiber

The daggerboards are made of carbon fiber which not only saves weight compared to standard composite boards but brings the stiffness required for such span. Because of the expected thin profile, they need to be carbon built to be stiff enough to be efficient.

Daggerboards in the middle

Few production catamarans opt for the daggerboards to be located in the middle of the hull, as this complicates and compromises their interior hull design. We have chosen to focus on performance while integrating the daggerboard cases into the interior layout