When sailing the Bahamas on my monohull it became very apparent to me that for some reason catamarans would always reach the destination before we did. Now i know why, but what i didn’t know was that trimarans are even faster! Actually, the world record for circumnavigating the world is set on a trimaran. so why is it that trimarans are faster than both catamarans and monohulls.
The main reason why a Trimaran is faster than a Catamaran of the same size and weight is that the Trimaran has less hydrodynamic resistance than the catamaran. Trimarans are using the same principles as Catamarans to move the boat forward but it is able to do it more efficiently since it spreads out the displacement over three hulls instead of two. This makes it possible to make each hull more narrow and thus more streamlined.
So that was the short answer, as always there are som more complicated and very interesting things about trimarans that need to be considered when speaking of which is faster. So to get a little more in depth answer let’s look at displacement and what it is.
Displacement on a Trimaran
Archimedes’ principle tells us that for a 5kg object to float it must displace 5kg of water, if it doesn’t, it doesn’t reach neutral buoyancy and sinks. This gives us at hand that the weight off the boat is very important. So whatever a trimaran would weigh (multiple tons) it would also have to displace that weight if it doesn’t want to turn into the world’s first trimaran submarine.
So comparing a catamaran and a trimaran of the same weight and length, the key really is the length in the water, you see since a 40ft catamaran has two hulls it can only displace the water over two points, and since you can’t make the hulls two narrow (the boat won’t displace enough water and sink) it needs to be quite wide, and trying to push something wide through the water requires more energy than something slim or more hydrodynamic.
On the other hand, the trimaran can displace the same amount of water, but on 3 hulls (or 1 hull and 2 floats, more on that in another post) this means that the hulls can be narrower and more hydrodynamic than a catamaran of the same length and weight. This reduction in hull drag is the main component and the reason why trimarans are faster than catamarans.
Consider the following examples, which one is easier, pushing a squared box through the water or pushing a tapered cone through the water? Even though these are extreme examples, they do a good job explaining how important hull shapes are. The box will have a hard time making the water pass around it and will almost
Planing or displacement hulls
So a boat can be configured as either a displacement hull (when a boat pushes away enough water for it to float whether if it’s moving or not) or uses a different method that makes the boat lift out of the water, something that is called a planing configuration.
This means that, much like driving a car and sticking your hand out the window, you can either make your palms horizontal and push the air around your hand(displacement), or you can tilt the front end a little upwards and give that hand of yours some lift(planing).
If you apply the same principle on a boat, this makes the hulls move up and out of the water, making the displacement of water much lower and so decreases the drag and makes the boat faster. You can see this on racing multihulls where one of the hulls actually rises out of the water! Which is both amazing and terrifying if you ask me!
Want to understand the difference between monohulls and multihulls? read this post!
How fast is a Trimaran?
The fastest solo sailing around the world(that is, one person alone without any help) was done by a Frenchman named Francois Gabart in 2017. He managed to average 27.2 knots(31.3mph) over 27,859.7 nautical miles! that is crazy fast, considering that the fastest circumnavigation by a monohull(also Frenchman) was done in 74 days and the fastest catamaran doing it in 50 days 16h 20min.
But the fastest all-time for a complete circumnavigation of the planet by any sailing vessel was completed in January 2017 by a mixed nations crew returning to port after only 40 days 23h 30m sailing their 100ft trimaran.
What Sailing boat is the fastest?
|Time to complete circumnavigating the world||Average speed circumnavigating the world||Highest speed recorded*|
|Type of boat|
|Monohull||74 Days||12.16 Knots||36 Knots|
|Catamaran||50 Days||22.2 Knots||N/A|
|Trimaran||40 Days||~29 Knots||56.3 Knots|
All data is collected from Wikipedia
This is many times a feisty discussion, and there are many approaches you can take to answering this question; you might ask, which one has ever reached the highest speed, or you might ask in comparison to a certain length, all these are fine. Those questions answer a far more narrow question. But I would argue that they don’t really answer the fundamental question of whether a trimaran as a type of boat is the fastest.
In my opinion, if you want to answer the “which is the fastest,” you must go to the extreme where nothing else matters except speed, and that is racing. If you also want to add some practical aspects, you make the boats go around the world. So that is why I think the fairest judgment of “which is the fastest” is who can circumnavigate the world in the shortest amount of time. And above you have your answers. Hope this post was useful and if you have any questions, let me know!