Motor Boat & Yachting - July 2018

NAVIGATION

Mel Bartlett

PRODUCTS

Nick Burnham

The latest marine engines and innovations

NEWTECH

DMS’s new stabilisation fi ns could

become a staple for motor boats

Flapping

marvellous

Dutch company DMS Holland is

hoping to revolutionise the market

for stabilisers with a new design of

flapping fins specifically designed

for fast-planing motor boats. The

company originally made a name for

itself with its cylindrical MagnusMaster

rotating stabilisers for displacement

boats, and last year it launched the

AntiRoll ‘flapping’ fins for superyachts.

Now it plans to develop this AntiRoll

technology into a smaller, cheaper,

more effective package for fast

production boats.

The key to this new design of high-

aspect ratio fin is that they attach

to the transom of the boat rather

than being fitted through the main

section of the hull. This makes

them easier to install (the hydraulic

actuators of traditional fins often

have to be tucked under the floor

of the master cabin) and ensures

that all the internal workings can

be kept in the engine bay, reducing

noise disturbance at night. It also

has a number of interesting dynamic

benefits. Because the fins rotate

on two different axes, they can be

swivelled all the way round so that

they tuck in behind the transom. This

not only reduces drag to negligible

levels at high speed, but also enables

them to double up as active trim tabs,

tilting up and down to correct both

roll and lean in much the same way

as Humphree’s Active Interceptors.

This means that instead of installing

separate trim tabs and stabilisers,

customers will soon be able to specify

one set of AntiRoll stabilisers that

should cover every eventuality from

trim and lean to stabilisation at high

speed, low speed and at anchor.

Although DMS Holland won’t yet

reveal the full details of how the new

system works across such a wide

range of speeds, the illustrations

appear to show three different

operating modes: high speed, low

speed and zero speed.

HIGH-SPEED MODE

At high speed, the fins tuck in along

the trailing edge of the transom

using small rotations of the fins

to deflect the water down and

create the lift on one side or the

other, much like an oversized trim

tab. The large surface area of the

fins and high pressure of the water

running over them at speed means

tiny movements will generate

substantial lift. When combined with

fast-acting electric actuators linked to

MY TAKE The market for stablisers

is developing so fast it’s hard to know

who’s winning the race, but the idea of a

one-stop system that replaces stabilisers and

trim tabs on fast boats is a tempting prospect. Hugo

Boats like this Fairline Targa

53 could benefi t from the new

high-speed stabilisers

By adapting its wing-like stabilisers

to fi t on the transom they work at

high speed, low speed and at rest