Unfortunately not based on my personal experience and watching others. That catamarans especially help with seasickness is a myth. In fact some catamarans seem to make seasickness worse because of their awkward, more unpredictable motion. I have sailed regularly the last decade thousands on miles in a variety of sea conditions on a variety of types of boats with a variety of crew. I also am prone to seasickness. While there is a difference in the motion of catamarans versus single hulled boats, the result for those who get seasick is usually the same. If you get seasick on one type of boat, you will likely get seasick on the other types. The more determining factors are the ocean conditions and whether you are taking anti-nausea medicine.
I remember one of my early offshore deliveries from Fort Lauderdale to Annapolis on a Lagoon 440 and how I hoped I would avoid seasickness on a catamaran after many experiences on monohull sailboats. Instead sailing a catamaran offshore triggered the worst seasickness experience of my life. People sail around the whole world but see some of the worst weather when crossing the Gulf Stream. Our route up the US Atlantic coast in the winter was routinely hit by strong nor’easter winds creating huge seas bucking the fast northern flowing current. Rounding Cape Hatteras was not fun. The conditions were bad, so I wondered if in other conditions on catamarans I would experience the same degree of seasickness.
I found it does not require significant weather to get seasick on a catamaran. I have felt nauseous in nice weather off Antigua on a Lagoon 42, in light trade winds on a Leopard 46. on a day sail of a Fountaine Pajot in the Dominican Republic. I would wager that I am in exclusive personal experience territory with seasickness. I have been seasick more often and for longer periods of time than 99.9% of other humans. I also have seen more people seasick than 99.9% of other humans. This following gives more details on the intricacies of catamaran seasickness.
The motion of the ocean
People who do not get seasick will never understand. And unfortunately seasickness is a huge determinant of how much you will enjoy cruising. Cruelly a study by 23andMe now suggests a significant determinant of seasickness is genetic. There is really is not much a person prone to getting sick can do about it other than take drugs or lay down and suffer.
The seasickness process goes in a consistent pattern. First you feel fine for like an hour or two. Then you get progressively more nauseous. Eventually people start asking if you are ok. You look “green” as is commonly said. Then you finally throw up which gives you tremendous relief for a little while. I usually throw up twice per hour for about 24 to 36 hours when starting on an initial sailing trip. The only thing that stops me from throwing up is sleeping.
One benefit of a catamaran for seasickness is the large cockpit with lots of space to lay down in. Also the open sterns to throw up into. Many memories are made on these patches of fiberglass.
Yaw, Pitch, Roll
The type of motion you endure between catamarans and monohulls is different. Another captain once likened to me the motion of a catamaran to a washing machine. There is more more yawing on a catamaran and unpredictability to the motion while a monohull has more specific pitch and roll motion. Monohulls are more back and forth and side to side while the catamaran feeling is circular, a “washing machine” like motion.
There is one type of boat that does decrease seasickness. That is a very large boat whether it be a monohull or catamaran. Larger boats can ride on the top of multiple wave fronts to balance out motion. Think of, for instance at the extreme end, a cruise ship. Most people do not get as sick on cruise ships as they would on a small sailboat. The bigger the boat, the more likely it can ride on multiple wave tops instead of going up and down between the wave period. You feel the ocean motion more. If you want to make sure you will not get seasick, then buy a mega yacht!
There also is a piece of equipment for large powerboats called a Seakeeper. It is a gyro stabilizer and after being mounted to the bottom of a boat will spin to stabilize the boat in a bad sea state. This is especially handy say when off fishing on a sportfish and you stop your motion. Stopping forward motion in rough conditions in the worst motion usually and the fastest trigger for crew to become seasick.
- Take drugs as directed at least half hour before sailing. Better to error on the cautious side even if the weather seems like something you might be able to withstand, the downside is steep and there is no turning back from sea sickness once it starts.
- Eat and drink non-acidic foods prior or during possible events. Acidic foods are terrible on the way back up. My recommendation is water and yogurt.
- If you feel seasick, lay down. Ideally laying down in the lowest part of the boat with the least yaw, pitch, and roll. Do not go down below the cabin and avoid fuel smells.
- Do not be afraid to throw up. And make sure to throw up downwind.
- Hand steering sometimes helps as you focus on the horizon and what is happening than how miserable you feel. But no guarantee it will help.
- After you get your sea legs, you no longer need to take drugs to prevent nausea. So if you take anti-nausea medicine for the initial day or two, then you can safely stop taking it and your body will have adjusted. Magically you will never get seasick yet you will have adjusted to the motion of the ocean. Beware that significant increases in sea state could still trigger another adjustment period.
If you get seasick, I am sorry to report than catamarans are not a miracle sure of seasickness. I wish it were the case as much as anyone, but the goal of this article is to kill that common myth you. Do not believe the salesman or charter operator and approach seasickness like any problem: with a Dramamine and an ice cold beer.