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TT - Selection Guide

The boatís wind area, the Ďlateral wind draft areaí and the thrusterís tunnel position in the hull determine the thrusterís performance on a boat. By knowing these factors we can calculate the wind pressure on the boat and the centre point of this wind pressure. From these calculations we can determine what thrust is needed to counter the wind pressure with the given thruster position. To gain total control of your boat, install both a bow and stern thruster, leaving the main engines to propel the boat forward and backward.

Vertical Retracting or Swing Thrusters - Selection Guide

Why do I need a Thruster?

A Thruster makes boat handling, especially in tight harbours, much eaiser by gently moving the Bow with a small independently driven prop without having to use the main engine.

I am buying a new boat but havenít decided to have a Thruster installed can it be fitted later?

Yes, there are plenty of installers around. It may cost a little extra and will involve hauling the boat and a few days of installation.

What Battery power do I need?

Thrusters have very powerful electric motors and it is recommended where possible to have a dedicated Battery close to the Thruster with a separate charger. This saves the problems of installing expensive, large cables from the main battery bank.

Can I install the Thruster myself?

The majority of the work involves choosing the location and installing the tunnel. A suitably qualified person should always carry out this work.

Can a Lewmar Thruster replace my existing installation/ I have a tunnel and standard fit by another manufacturer?

Yes in most cases providing the tunnel has the same internal diameter.

Manoeuvring around the dock area can be difficult, but Lewmar's TT Thrusters make docking simple. The revolutionary design of the TT propeller, the latest in Lewmar's long history of custom thruster solutions, achieves perfectly even thrust in both direction for maximum control and manoeuvrability. All Lewmar Thrusters have been extensively tested, resulting in a smooth, efficient and quiet performance that will have you docking like a pro in no time.

Take Control. Enjoy your boating. Fit a Lewmar Thruster

As marinas get smaller and berths get tighter, safely docking a boat is more challenging than ever. Thrusters give you total control of your boat and allow you to manoeuvre into and out of tight spots with ease

Some good reasons why thrusters improve your boating

  • Docking your boat is easy; it makes you look like a professional skipper.
  • Boating is meant to be fun. Why end your day or week on the water with a stressful experience?
  • A thruster offers the help you need to be in full control when docking and departing regardless of wind conditions and currents.
  • Short of crew? A thruster makes you less dependent on having a skilled crew. The independence a thruster provides will allow you to use your boat whenever you want, whether alone or with others.
  • Every boat can benefit from having a thruster installed.

Choosing the right Lewmar thruster for your boat.

Today most yachts or motorboats over 45 feet have a bow thruster fitted as standard. The thruster will usually meet the expectations of most customers when using the boat under normal weather conditions. The sizes used by boat builders will vary depending on the boat's intended usage and price level. In today's production boat's of around 45-50, the typical thruster will push the boats bow against a direct side wind of 20-22 knots.
For boat owners who use their boats in more demanding conditions or have a strong current in their local marina, Lewmar can offer upgrades to a higher performance thruster. However, few pleasure craft need a thruster that can push the bow against a direct side wind of more than 25 knots.
The boat's wind area, the lateral wind draft area and the thruster's tunnel position in the hull determine the thruster's performance on a boat. By knowing these factors we can calculate the wind pressure on the boat and the centre point of this wind pressure. However the wind pressure is seldom from right angles and many boat superstructures are quite streamlined so we can reduce the factor slightly. From these calculations we can determine what thrust is needed to counter the wind pressure with the given thruster position.
Our selection chart
To gain total control of your boat in combination with a bow thruster the solution is to install a stern thruster, leaving the main engines to propel the boat forward and backward as they were intended

TT Electric

For highly controlled manoeuvring in restricted situations Lewmar's TT ELECTRIC Thrusters represent a move forward in design and function. Easy installation and maintenance free operation are benefits that will attract both builders and owners. A comprehensive program of testing has proved that the new Lewmar Thrusters deliver efficient, balanced and supremely quiet performance.

TT Hydraulic

A full range of hydraulic thrusters from 185 to 300 are available with all the benefits of the standard range TT thrusters. The compact hydraulic thrusters offer significant weight saving and extend motor running time. Hydraulic versions need to be run from an external power source.

IP Thrusters

IP Thrusters are certified for use in Ignition Protected areas designed for gas boats.
  • Ideal for wet areas such as Stern installations.
  • Covers can be supplied as a kit. This would only be offered as a 'waterproof' solution as the installation is the customer's responsibility.