Monohull vs Trimaran
Which is better, a monohull or trimaran?
Since we have recently made the switch from a monohull sailboat to our speedy trimaran, I thought I would shed some serious light, and weight, on the subject!
Let’s first recap our two comparison vessels which we have over 10k miles of sailing with each:
39ft Amel Sharki - ‘Panda’
The Amel Sharki is very much defined as a ‘classic’ monohull in terms of her construction, design brief, and sailplan. She was designed ideally for a couple to sail around the world comfortably. Built in 1980 by Amel in LaRochelle, France, Panda was hull number #12 of this really cool Sharki range. With an integral keel, skeg hung rudder, she was outstandingly sturdy. The glass was not cored (except for the decks), and very thick in places (we measured over 1.5” at the centerline for the depth-sounder hole). The sailplan was easily managed being ketch rigged, thus essentially reducing the mainsail size in two smaller sails.
45ft Neel Trimaran - ‘Panda ROSSO’
A unique design philosophy in the world of multihulls, introduced by Eric Bruneel, this range of trimarans has a bridge deck layout. Unlike your typical trimaran, which is essentially a much narrower monohull with amas (the out-rigger things!), our Neel boasts a high and wide surface area above the main hull, allowing for a comfortable living space. The design brief is similar, but with a nod to performance. The hull is fully cored with PVC foam, sandwiched between two layers of glass which the resin is infused via a vacuum bagging process to eliminate any extra resin. The rudder is a free-standing spade, small integral keel in front of a modern Volvo saildrive. The mast is a fractional variety with aft sweeping upper and lower shrouds, twin forestays with furling headsails, and single diamond spreaders.
Ok, you have given me a lot of information, but which is better?
It is difficult to give an ‘overall’ rating, so lets break it down point-by-point:
Stability: Inherently, a multihull is more stable due to its width. While sailing, a trimaran does heal a little, somewhere in between a monohull and a catamaran. While at anchor, our trimaran does rock a little, more so than a catamaran, but less than a monohull.
Performance: Since a multihull is inherently stable in it’s design due to its high ‘form stability’, it thus lacks a deep keel with ballast and it’s weight is dramatically reduced! For example, our Amel weighed in at 12 tons, whereas our Neel is just over 7.5 tons, for a much larger boat. Additionally, the hull shape of a multihull allows for long, slender, profiles which essentially lack a ‘hull speed.’ Thus, we are no longer limited to around 7-8 kts for our waterline length. Instead, we can push into the low teens, and have topped out with a long Atlantic Ocean surf of 19.7kts!
Maneuverability: Our trimaran has one engine, and one bow-thruster, essentially like a mono without a keel to turn around. Thus, her ability to maneuver in the harbor is tough to say the least! With so much windage, she gets blown sideways easily, and her high-tech, low-drag, folding propeller lacks serious thrust in reverse and has almost no noticeable prop-walk. Our Amel had no bow thruster, but a good amount of prop-walk and I found it easier to dock than the Neel. However, for our style of sailing, we rarely visit a dock, maybe once every 2-3 months so we find the difficulty worth the trade-offs.
Safety: This is a huge topic with lots of sub-topics, but lets start with impacts. The foam core is probably less resilient to a hard grounding compared to the Amel. However, in a serious water ingress situation, I feel the Neel would fair much better having three separate hulls which are highly compartmentalized. I have heard of one case of a Neel’s central hull flooding and the owner sailing another 200nm to port as the ama’s supported the extra flotation requirement.
Costs: Multihulls are a clear looser in this catagory. They are generally larger, thus more systems, bigger sails, taller rig, and simply more cost. Those costs continue through ownership with additional maintenance and increased docking / mooring fees. Looking to haul-out? Think twice, or three times! Our Neel 45 is 28.5ft (8.6m) wide, which leaves us to only a handful of lifts and trailers which can accommodate her beamy ways. A monohull wins on all fronts, especially when hauling out as facilities are generally built around this style of boat.
Sailing Pleasure: I just love the way a monohull sails. There is something sexy, like a ‘poetry in motion’ about their stride through the water. The feel through the helm, the heel during a gust, and the gate through a swell is un-matched by a monohull. But, what is the next best thing? A trimaran of course! On our Neel we also heel and have great helm feedback, which a typical catamaran lacks. Now the motion upwind can be described as bouncy, which is different than the Amel which was as smooth as you’ll get in a monohull. But, interestingly, due to the super narrow hulls, we almost don’t slow down when slicing through a wave-state. There is no pounding, no bridge deck slamming, just a clean slice through the sea!
Well, that was a lot MORE information, but hey, which is BETTER?
If we were to give an overall score, we would personally have to say our trimaran wins out over the monohull. In terms of sailing and passage-making, we find ourselves enjoying the extra speed. Especially running downwind, our Neel is stable and fast! And with that stability comes extra comfort aboard. We are noticeably less fatigued mile-by-mile than our monohull.
This probably didn’t really help you decide, but I hope it sparked some thoughts. With sailboats, there are ALWAYS compromises and in the end, it comes down to your personal preference including cruising style, budget, and accommodation needs, among a laundry list of desires.
Darren Seltzer