BOW THRUSTER LAKE MAGGIORE

YACHT SERVICE - Bow Thruster Lake Maggiore.
Marine technology: criteria for selecting the right bow thruster.

YACHT SERVICE - Bow Thruster Lake Maggiore analyses the advantages of installing a bow thruster in terms of safety and manoeuvrability:

A bow thruster helps to increase a yacht's ability to turn even in the tightest of spaces and to counteract drift caused by crosswinds during manoeuvres with slow speed. In addition, a bow thruster also allows the bow to turn sideways when the ship is completely stationary, which can be particularly helpful during docking and casting off manoeuvres.

Especially the following boat or propulsion types have a limited manoeuvrability, which can be considerably improved by using a bow thruster:
- Power boats with only one shaft drive are more difficult to manoeuvre than boats with two propellers, which can be used to turn the boat on the spot and accordingly perform manoeuvres with smaller radii.
- Sailing yachts with two rudder blades have the disadvantage that none of the two rudder blades is directly exposed to the water flow from the propeller and thus the rudder system loses efficiency, especially during manoeuvres at slow speed.
- Sailboats with a Sail-Drive are also disadvantaged in their manoeuvrability, because the distance between propeller and rudder blade is relatively large. The efficiency of the rudder system during manoeuvres at low speed is limited because the current generated by the propeller does not hit the rudder blade with sufficient force.

A bow thruster not only guarantees better control of the vessel through improved manoeuvrability, but also increases the skipper's personal feeling of safety. In short: somewhat more demanding mooring manoeuvres are easier to master with a bow thruster!

When buying a new ship, especially if it is a larger one, you should remember to have a bow thruster installed immediately, if it is not already standard equipment. If you decide to install it later, a retrofit is basically possible.
The installation in the ship has to be as far forward as possible. The thrust generated by the bow thruster acts with a large lever arm on the ship's system and guarantees a high efficiency of the system. At the same time, however, the bow thruster must be located deep enough in the water. If it is too close to the waterline, part of the thrust is lost through cavitation and the efficiency of the system is reduced. Both are obviously contradictory requirements, which make a compromise necessary when choosing the position of the bow thruster.

Another factor influencing the installation is of course the interior layout, the equipment and the resulting space conditions in the fore ship.
Depending on the existing conditions, a choice can be made between different installation options. Roughly speaking, bow thrusters are available in three versions:
- The tunnel bow thruster consists of a propeller that generates its lateral thrust in a tunnel. The tunnel itself is installed in the bow area across the underwater hull. In order to be able to install it deep enough, it often cannot be installed very far forward and is therefore already located in areas where the equipment has to be heavily modified to make room for the system.
- Retractable bow thrusters, on the other hand, allow installation far forward in the bow area. When they are used, the propeller is first moved out of the hull and thus works at a sufficient water depth.
- Bow thrusters as attachment systems consist of streamlined housings which contain the entire system and are attached to the hull from the outside. Compared to the two systems listed above, installation is relatively simple and is also possible if there is no space available in the fore ship itself for installation.

The size of the system and thus the developed thrust depends mainly on the following factors:
- hull length and displacement
- hull sides
- Lateral resistance of the underwater hull
- average wind and current conditions to be expected in the area
- the average space expected in the ports of call

When determining the power requirement of the bow thruster, it should be borne in mind that electric bow thrusters have a limited operating time due to the risk of overheating. The duty cycle is often limited to a few minutes. For this reason, too, it is advisable in principle to overdimension the system.
An approximate guide value in relation to the necessary thrust in Newton of a bow thruster, depending on the length of the ship, is given in the following table:

When installing a bow thruster, the following points must also be observed, to which YACHT SERVICE - Bow Thruster Lake Maggiore makes special reference:
- Under no circumstances should the installation of the system lead to a structural weakening of the keel and the bottom area as a whole. The forces acting on the vessel from outside, e.g. in the event of heavy pitching in the bow area, must not be underestimated.
- The current required during operation flows only for a relatively short time, but is very high. This requires correctly dimensioned cable cross-sections, which often have to be as thick as a thumb, depending on the length of cable laid, and must be appropriately fused. It may be necessary to retrofit batteries with sufficient capacity and corresponding charging options. For safety reasons alone, integration into the existing electrical system must be carried out in accordance with current regulations.

YACHT SERVICE - Bow Thruster Lake Maggiore.
Your specialist company for marine technology advises and installs bow thrusters.

YACHT SERVICE - Bow Thruster Lake Maggiore will be pleased to advise you on the planning and installation of the optimal bow thruster for your ship.