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Selecting the right Thruster solution for your boat


To help you with your choice of Thruster needs see out Selection Charts to make it easier.

Great knocked down prices on any new Thrusters Supplied & Fitted,
Please fill in the Online Quotation Form or Contact Me to get your Special Deal.

> Tunnel Thrusters
> Retractable Thrusters
> Bow Thusters & Stern Thrusters
> Electric or Hydrualic power source
> Thruster Selection Charts

Positioning thrusters is often as important as choosing the right thrust output when seeking maximum manoeuvring performance for your yacht.
Thruster turbines need to be placed one full propeller diameter under the water line to achieve optimum thrust. The thruster must also be positioned as far forward in the bow or as far back in the stern as possible. A thruster stepped back from the bow (or stern) would need to be more powerful than one mounted further forward (or back), to achieve the same turning effect on the yacht.


Tunnel Thrusters


tunnel thruster

Most motor yacht designs are well suited to fixed tunnel thruster installations. However, the above-described constraints (depth and positioning) often contradict each other, especially in modern sailing yachts.
Although some sailing yachts can achieve good results with tunnel thrusters, most modern designs would work better using a retractable solution.

Widely used and often fitted as standard on many motor yachts, tunnel thrusters are easy to fit and highly cost effective.
When installed at the correct immersion depth and using the shortest tunnel length possible, tunnel thrusters offer an ideal solution for motor yachts and even deep-footed sailing yachts when sailing performance is not paramount.

Southern Marine Services full range of tunnel thrusters offer a wide choice of power outputs and 4 different sized tunnels to suit yachts from 17-85’.

Tunnel Thruster (Electric)
Tunnel Thruster (Hydraulic)



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Retractable Thrusters

Retractable thrusters are easily installed far forward in the bow whilst still achieving the required immersion depths, even in today’s modern performance sailing yachts.
This results in a thruster that has a good turning effect on the yacht, often even allowing a unit with a lower thrust rating than its tunnel equivalent to be used with excellent results.

When retracted these units have no affect on the yacht’s drag and therefore do not reduce sailing performance in light winds.


Furthermore, retractable units minimise loss of buoyancy. The weight of water in a tunnel thruster’s tube is an often neglected factor that can affect a yacht’s performance. Retractable thrusters minimise this problem as the retractable thruster’s box only partially fills with water.

Retractable Thrusters (Electric)
Retractable Thrusters (Hydraulic)


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Bow Thrusters and Stern Thrusters

The combined use of a bow and stern thruster adds a whole new level of control when manoeuvring in difficult conditions or tight corners.

Turning on the spot or even stepping the entire yacht sideways becomes possible at the flick of a switch.

Max Power offers stern thruster adapters for the entire tunnel thruster range. A range of Ignition Protected thrusters is also available thus enabling the use of a stern thruster in habitually damp zones or petrol-powered yachts.

On boats where conventional tunnel stern adaptors cannot be used due to lack of immersion depth or the positioning of drive systems, retractable stern thrusters offer an attractive & powerful solution.



Electric or Hydraulic Power Source ?

Powering your thrusters

Bow and stern thrusters whether retractable or tunnel require a power source. On a yacht this can be either a 12/24V DC (electric) motor or a hydraulic motor.
The hydraulic motor will need to draw power from a thermal engine (via a hydraulic pump) or a remote mounted DC motor (also via a hydraulic pump).
The DC motor will draw power directly from a battery bank.

The choice of power will depend on factors such as frequency of use, runtime required, and thruster size needed.

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