Steady as she goes with Seakeeper

Posted by: Pen Marine

Having a stabiliser on your boat will change your life out at sea

Depending on where you see the information, it is said that roughly one third of everyone in this world is susceptible to motion sickness. For those blessed to never experience kinetosis (a fancy word for motion sickness), the nausea, anguish and discomfort during an episode of sea sickness is hard to explain. So with this in mind, today we will look at the types of stabilisers and why you really should get one.

What is it?

A stabiliser is as its name suggests, and it dramatically reduces the roll of a boat or yacht, therefore giving everyone on board a more comfortable time. This also makes it safer as hard rolls may cause passengers and crew to fall or drop breakable items. There are currently two leading active stabilisation technologies – fins and gyros.

Fin stabilisers do their work in the water, and their placement along the bottom of the hull depends on the design of the hull. Boat designers often place fixed fins here for stability as well, but we will look specifically at active fins. Sensors will tell these fins to ‘flap’ up and down when the boat is at rest to generate force and thus keep the boat relatively calm, though the angle of the ‘flap’ is limited.

However, this type of stabiliser is most effective when the boat is moving through water, where the force generated depends on the speed of the craft. The angle of the fins are constantly adjusted by sensors to give the best ride quality, and you can think of it like an aircraft wing, or a spoiler of a car.

Gyroscopic stabilisers, however, work the same whether the craft is at rest or moving and you can imagine the gyro as a large spinning ball. When the boat rocks from left to right, sensors will activate the motor, which then spins the ball at right angles to the rocking motion to resist it. Unless the sea is glassy smooth, the system will constantly work to resist any kind of roll, therefore improving ride quality.

Unlike fin stabilisers, the speed of the boat makes no difference, but a gyro is limited by the angle and speed of its precession  (a gyro’s tendency to react to an input force at right angles to said input force).

Pen Marine is an official dealer for Seakeeper

Seakeeper is the pre-eminent maker for gyroscopic stabilisers. Unlike fin stabilisers, gyros do the same good work when the yacht is anchored or away. This means you don’t have to worry about pesky waves from passing boats anymore when entertaining guests at port, and you can also cruise comfortably to nearby islands.

What’s more, fins can get damaged on shallow water, and require constant cleaning from befoulment. Seakeeper recommends a service for their gyro stabilisers once a year, or every 1,000 hours of operation for the smaller models (2,000 hours for the larger models). They have a solution for almost all boat sizes, from small crafts of 23 feet to behemoths of 85 feet and larger.

There are a couple of challenges if you want to get one for your boat, and they are space and weight constraints. For example, the smallest Seakeeper model weighs in at 165kg, and is roughly 2x2x1.5 feet – the size of a microwave oven, if you will. The good news is that this small model can be glued literally to the deck under the leaning post or under chairs. Otherwise,a small box with accoutrements can be built over it and it can still be used to stow items or seat people.

A gyro stabiliser is one of the best investments you can make for your boating journey and for your family’s boating experience, as young children are usually more susceptible to motion sickness. It may even give you a new appreciation for a yacht that you’ve had for many years. Get in touch with us if you want to add a dose of comfort to your seafaring.