Hugo Andreae takes a look at stabilisation specialist Seakeeper’s new active Ride control system
I t’s fair to say that Seakeeper’s range of gyroscopic vacuum-mounted stabilisers revolutionised the market for zero-speed anti-roll devices, so when the same marine motion control specialist claims its new Seakeeper Ride active trim system will be ‘the next big thing in boating’, it’s worth paying attention.
In fact Seakeeper would rather we didn’t refer to Ride as a trim system at all but as a Vessel Attitude Control System (VACS).
That’s because it does far more than just automatically correct trim and list angles, it also continuously monitors, adjusts and controls the entire attitude of the boat over each and every wave. So responsive and powerful is this new system that Seakeeper claims it can eliminate up to 70% of pitch and roll as well as offer a host of other benefits.
These include reducing time onto the plane, compensating for changing crosswinds and uneven boat loading, and actively coordinating turns for a smoother, safer ride. In layman’s terms, it’s said to feel a bit like the boat is “magnetically attached” to the water.
CUPPED BLADES
The hardware itself does share a certain amount in common with existing trim systems in that it consists of two separate units that attach to the transom in line with the trailing edge of the hull and generate lift by intercepting the flow of water as it leaves the hull. By increasing lift on one side or the other, this adjusts the list/ heel angle, while adding or reducing lift on both sides at once controls the fore and aft trim, in much the same way as a basic set of trim tabs.
That said, Seakeeper’s new Ride system is actually closer in principle to the interceptor style trim tabs used by Zipwake, Volvo and Humphree but rather than featuring vertical interceptor blades that drop down in line with the transom, the Seakeeper system uses a rotating arm with a cupped lip that swings down from behind the transom. They both generate lift by trapping a wedge of highpressure water in front of the protruding surface that forces the main flow of water downwards and pushes the hull up, but according to Seakeeper this rotating arm design allows for exceptionally rapid movements, very efficient lift and excellent reliability.
SPEED AND CONTROL
Andrew Semprevivo, president and CEO of Seakeeper, told MBY: “We played with tabs and guillotine-style blades and could’ve had an improved automatic trim system on the market years ago but we weren’t interested in doing the same thing but better, we wanted something different. Rotary provided the breakthrough we were looking for. It was the only way to make it fast, powerful and reliable.”
