Tag Archives: Ship propulsion

Wartsila Propulsion Control System

The Wartsila Propulsion Control System (PCS) is a comprehensive system of control devices, displays, indicators and modules designed to suit all possible propulsion configurations of a modern ship.

The human interface of Wartsila PCS, ProTouch, is a complete system of levers and touch screen interfaces, that responds to market demands for modern and compact control devices.

Wartsila ProTouch is the human interface of the Wartsila PCS. It represents a state-of-the-art response to market demands for control devices that are modern and compact. With its safe and intuitive arrangement it gives the power to the user.

Wartsila ProTouch has won the Red Dot Design Award, Best of the Best 2013.


  • Touch screen technology for user friendly, intuitive operation.
  • Simple installation and commissioning.
  • Compact, space saving design.
  • Fully customizable to fit all propulsion products and layouts.
  • Also available for retrofits.


The components of the Wärtsilä Propulsion Control System can be combined into configurations suitable for a wide range of applications to meet the requirements of redundancy and independency needed for merchant shipping, as well as more complex offshore applications.

With the capability to control up to 8 propulsors from up to 5 operator stations, the system covers a vast majority of applications and propulsion layouts.

Key benefits

Compact design : The whole system footprint is reduced significantly allowing optimisation for ergonomic needs and meeting functional requirements.

Modularity/flexibility : The extended modularity of hardware and graphic user interfaces offers a flexible solution for any vessel layout. The system fits all the propulsion products and, as a result, all types of vessels.

Safety : the system improves safety, both at sea and in port by removing the visual challenge of finding critical information, it provides the user the relevant information when needed User friendly, intuitive operations: By the means of the modern displays, with touchscreen technology, the operator can easily get all the functions and information handy. The system will guide the user when a more complex sequence or action is required. Also, the system can support any language.

Simpler installation and maintenance : The system minimizes installation time and costs, simplifies commissioning and reduces maintenance needs because the PCS is fully pre-configurable and the components communicate by a redundant field bus with minimised number of cables.

Integration with other systems : The system enables easy integration via serial interfaces towards for example VDR, IAMCS and DP/AP systems.

Technical info

Modularity and configurations

The system’s modularity makes installing, commissioning, configuration and maintenance simple and efficient, thus saving valuable time. Up to 8 propulsors can be controlled at up to 5 operator stations in order to cover the vast majority of the applications. All bridge devices are connected to a redundant CAN OPEN network.

The system enables easy integration with other systems via serial interfaces with other systems at bridge level. Protocols like MODBUS RTU RS485 and NMEA 0183 are supported for VDR, IAMCS and centralized dimming.

Six lever types are available for different propulsors.

  • Single and double levers for fixed pitch / controllable pitch (FPP/CPP) main propellers.
  • Single and double levers for Tunnel thrusters (TT)
  • Steerable thrusters (ST) and Waterjets (WJ).

Each lever is standard equipped with stepper motors for automatic line up during control transfers and electronic detents. Each lever is equipped with a led bar giving the operator instant visual information on the active propulsion mode. A separate back-up system is integrated in the lever as well as a hardwired emergency stop circuit.

Touch screens

The capacitive touch screen displays are in two sizes; a 4.3” side display and a 10” main display. The latter is optional and used for multi propulsor plants providing a single user interface for common functions like dimming and control.

Compact design

The components to be installed at the operator stations of the bridge and engine control room are interconnected by field bus technology (CAN OPEN) and thus require a minimum of cables. The entire system’s footprint is reduced significantly, thereby allowing the designers more flexibility to place the propulsion components according to the operators’ ergonomic needs and for meeting the functional requirements of the complete operator station.


The extended modularity of hardware and graphic user interfaces offers a flexible solution for any vessel layout. The system fits all propulsion products and, as a result, all types of vessels. The components of the system can be combined into configurations suitable for a wide range of applications to meet the requirements of redundancy and independency needed for merchant shipping, as well as more complex offshore applications.


By removing the visual challenge of finding critical information in large panels of buttons and gauges, and by giving the user relevant information as and when needed, the system improves safety, both at sea and in port. In case of a control transfer, the levers are automatically lined up enabling operators to remain focused on their navigational tasks. The main propulsion levers are provided with back-up facilities integrated in the same lever allowing the operator to respond adequately and control smoothly in case the back-up system needs to be activated.

Wartsila Propulsion Control System
Wartsila Propulsion Control System

User friendly, intuitive operations

The modern displays feature touchscreen technology, thus allowing the operator simple access to allfunctions and information, and providing full and easy control. The system will guide the user when a more complex sequence or action is required. Immediate feedback is given also by the led colour on the lever, showing the current status of the selected propulsor.

Simpler installation and maintenance

The PCS is fully pre-configurable, thereby minimizing installation time and costs, simplifying commissioning, and reducing maintenance needs. Integration with other systems : The system enables easy integration via serial interfaces with other systems at bridge level. Protocols like MODBUS RTU RS485 and NMEA 0183 are supported for VDR, IAMCS and centralized dimming. The system is suitable for being adapted to control competitor (OEM) propulsors.

RGB status LED – colour range

The RGB LED supports operators and pilots by giving instant visual information regarding the selected mode and status.

Configurations and options Wärtsilä PCS configurations :

– Up to 8 propulsion units (all types of propulsors)
– Up to 5 stations

Wärtsilä ProTouch options :

– 2 display sizes 4.3” and 10”, day/ night mode, portrait or landscape position.

– 6 types of levers (TT, CPP, ST, WJ). Six different levers have been developed using a modular approach :

– Single and double levers for fixed pitch / controllable pitch (FPP/ CPP) main propellers.
– Single and double levers for Tunnel thrusters (TT).
– Steerable thrusters (ST) and waterjets (WJ).

Related article : Wartsila EnergoFlow; Wartsila Controllable Pitch Propeller Systems; Wartsila Fixed Pitch Propeller

Drives for marine propulsion and thrusters

Excellence in electric main propulsion

Electric-based main propulsion provides a great deal of freedom in ship design, and ships can be designed much more efficiently without the traditional limits on equipment layout, due to mechanical restrictions.

Benefits of electric propulsion :

  • The power can be supplied by any number of generators, which enables high redundancy.
  • The motor + drive combination consumes energy only when the azimuth thruster is actively turned.
  • The environment benefits from lower fuel consumption and exhaust gas emission levels.
  • Electric propulsion is a good platform for the next phase of development – hybridization.

Generally speaking, the design of vessels with modern electric propulsion systems, either diesel electric, LNG electric or even fully electric, can be quite easily converted to a hybrid solution. In the best case, just by adding a parallel E-Storage system, a vessel can be operated utilizing battery power for example for peak power demand. In some cases, the optimum solution is to use DC power distribution instead of, or in conjunction with, traditional AC power distribution.

Danfoss Drives’ solutions for the marine and offshore industry have the highest number of class type approvals from nine authorities: DNV-GL, ABS, Bureau Veritas, Korean Register, CCS, RINA, Lloyds Register, RMRS and Class NK.

This gives you the best possible choice when selecting drives for your marine application.

Shaft generator for optimal propulsion with PTO/PTI

Many long-haul vessels are still operating with direct diesel propulsion and no electric propulsion system at all. These vessels can improve efficiency and optimize main engine load power and emissions by adding a shaft generator/motor between the propeller and the main engine. This solution, called Power Take Out and Power Take In (PTO/PTI), is an electrical add-on which makes these vessels more efficient and even ready for hybridization. In hybrid vessels, a shaft generator/motor with AC-drive technology allows the optimum control of propulsion machinery at various speeds, which saves energy.

Clean hybrid propulsion

AC drives have key roles in hybridization and integration, and offer answers for the marine and offshore industries, which are looking for ways to reduce consumption of diesel oil and minimize emissions. A move towards using cleaner fuels like liquefied natural gas (LNG) is already in place. The future will be a move towards the operation of fully electric vessels. In the meantime, shipyards and vessel owners are investing more and more in marine hybrid systems to increase flexibility in design and installation, optimize operational performance and minimize the environmental impact. Many vessel types from small shuttle ferries to huge aircraft carriers can utilize hybridization technology for a more efficient and cleaner performance.

Clean hybrid propulsion
Clean hybrid propulsion

The benefits are clear business drivers :

  • improved vessel performance.
  • reduced emissions.
  • lower operating costs due to lower fuel consumption.
  • lower maintenance costs related to diesel engines.
  • reduced noise levels.
  • improved long-term efficiency of the power supply system.

How hybridization works

Hybridization utilizes AC drives in the form of power conversion and grid converter technology. VACON® drives are in place when hybridized energy production is used with generators, and hybridized loads is used, for example, with propulsion and cranes.

Hybrid vessels run using two or more power sources: Main engines and generators are usually combined with integrated energy storage in the form of batteries or super capacitors. The intention is first to hybridize either the energy production to ease up the main engine optimization and secondly to hybridize all machinery consuming the energy to optimize machine behavior.

The marine and offshore industry recognizes the potential of using hybrid power and innovative propulsion systems. They reduce emissions and improve fuel consumption while extending engine maintenance intervals and engine life. With hybrid solutions, it is even possible to reduce the size of the engine, saving investment costs and space on board.

In energy production, the flexibility comes in the form of ‘time’. Energy storage gives time for generation to react to changes in loading conditions in an optimal way. On the load side, loading behavior is not reliant on generation and is ‘time’ constant.

Proven feedback and design targets from operating hybrid vessels has shown that using multi-source energy solutions to power vessels can reduce fuel consumption by 20–30%. You can choose to stop a diesel engine and run on battery or a smaller generator, or disconnect the battery or generator and start the engine again.

In the case of special vessels like tugs and support vessels, for example, they spend a lot of their service time idling with the main engines running and ready to respond, but no power is actually being used for propulsion. With hybrid solutions, batteries and smaller diesel generators can be used to provide energy to the vessel when it is idling, in standby operation, while harbor maneuvering or transiting short distances. A similar process can be used with regard to ferries operating in start/stops and scheduled routes. With regard to dynamic positioning, batteries can be used to provide the power for propulsion until the additional main engine is started and accelerated to provide long-term power for propulsion.

Thruster control for precision maneuvering

Precise maneuverability in all seas is what you need from a thruster, and that is what Danfoss drives deliver, with their high torque capabilities and fast, accurate performance.

Danfoss drive controlled variable speed propellers with fixed pitch are typically 20-30% more energy efficient than fixed-speed variable-pitch propellers – which waste approximately 20% of the power at zero thrust.

Frequency-controlled variable-speed propellers use 50% less energy than hydraulic variable-speed propellers. The need for special motor preheat function eliminates an anti-condensation heater.

Electrically-steered azimuth thrusters deliver more accurate control and respond more quickly than a hydraulic steering system. A minimum of two parallel motors and drives are always in use. If one combination stops, the steering system continues to operate.

Steering gear

With variable-speed control, you can achieve accurate rudder positioning, enabling a precise analog control system. In rotary-vane steering gear with reversible hydraulic pumps, use a VLT® or VACON® drive to change speed and direction, saving energy by only running when the vessel is changing course.

Read more : Hybrid marine electric propulsion system;  Propulsion System

Parallel hybrid propulsion for AHTS

A compromise between performance, energy efficiency, and investment.

One of the reasons for the suitability of electric propulsion for OSVs is the large variations in the load profile of propulsors and thrusters. Total engine capacity has to be dimensioned to achieve the design speed of the vessel, or the dynamic positioning (DP) capability in the worst weather situations. As most newbuild vessels are classified as DP 2, with redundancy requirements, the total installed power might be much higher than that required for average loads.

Electric propulsion makes it possible to increase energy efficiency by running the propellers at variable speeds to reduce hydrodynamic losses, as well as optimizing the power plant configuration and operation to ensure a closer to the best possible working condition for the diesel engine prime movers. Until recently, nearly all anchor handling tug supply (AHTS) vessels were built with diesel-mechanical propulsion due to an overriding focus on bollard pull requirements, even though their operational profile made them even more suitable candidates for electric propulsion, compared with OSVs. For smaller AHTS vessels, there are few reasons for not selecting electric propulsion. However, higher investments demanded by this solution make such a commitment more challenging for shipowners. A parallel hybrid solution may then be a good trade-off, where additional building costs are lower, while some of the important fuel-saving characteristics of diesel electric propulsion are accrued.

Energy efficiency of electric propulsion

Electric propulsion has demonstrated substantial fuel reduction, compared with direct mechanical propulsion in OSVs (Figure 1). The fuel savings will often reach 15- 25 percent in typical operating profiles and as much as 40-50 percent in pure DP operations. As a result of this, together with an increasing awareness on operational costs and environmental emissions, a large part of the OSV fleet is now specified by the oil companies and charterers to be equipped with electric propulsion.

Conventional direct mechanical propulsion
Conventional direct mechanical propulsion

Reduced fuel consumption in an electric propulsion system can be attributed to two key elements. The first is the variable speed control of the propeller, which reduces the “no-load” losses of the propellers to a minimum compared with classical fixed-speed controllable-pitch propellers. The second element is the automatic start and stop of the diesel engines, which ensures that the engine load is kept as close to its optimum operating point as possible, within the limits of operation.

The classical design of an offshore support vessel, including an AHTS vessel, uses fixed-speed propellers with controllable pitch. Compared with variable-speed control of the propeller, this is a very inefficient way of controlling the thrust due to the high “no-load” losses of the fixed speed propellers (Figure 2). This alone contributes to most of the savings in electric propulsion when applied to offshore vessels. In addition, the utilization of the thruster capacity in DP operations is very low for most of the days operational in, for example, the North Sea, even though this is regarded as a harsh environment.

2. Comparison of shaft power versus provided thrust from a fixed-speed controllable pitch propeller (CPP) and a variable speed fixed-pitch propeller (FPP).

fixed-speed controllable pitch propeller (CPP) and a variable
fixed-speed controllable pitch propeller (CPP) and a variable

3. Fuel consumption per kWh of produced energy.

Electric propulsion also offers the potential for the optimal loading of the diesel engines by using a number of smaller engines, compared with using a smaller number of larger units. Depending on the load, the automatic start and stop of the engines yields better loading and thus reduces fuel consumption (Figure 3).

Fuel consumption per kWh of produced energy
Fuel consumption per kWh of produced energy

4. Impact of ratio of station keeping mode versus transit mode in fuel saving of diesel electric systems, this is for illustration and not calculated for a particular case.

This reduction in fuel consumption is to some extent counteracted by the higher losses in the transmission system between the diesel engines and the propellers. While losses in the shaft line and gear box of a conventional design are of the order of a few percent, transmission losses in a diesel electric system are in the range of 8-11 percent depending on the concept and efficiency of the components in the drive train. Hence, the potential for fuel savings is highest for vessels with an operational profile where much of the time is spent in DP, standby or manoeuvring, while the benefits are less obvious, absent, or even negative where transit at high speed is the dominating operational mode (Figure 4).

Impact of ratio of station keeping mode versus transit
Impact of ratio of station keeping mode versus transit

5. Electric propulsion and direct mechanical propulsion for a 200+ metric ton bollard pull AHTS.

The same mechanisms for energy efficiency and fuel savings that are proven in the OSV segment are available for AHTS vessels; in fact, they are more compelling. In an anchor handler, the peak power is determined by the bollard pull requirement for the vessel, which in most cases will be further from the average load point the higher the bollard pull is. A calculated case study shows that for a 200+ metric ton bollard pull AHTS vessel, fuel consumption will be 1,900 metric tons lower when electric propulsion is used (Figure 5).

Electric propulsion and direct mechanical propulsion for a 200+ metric ton bollard pull AHTS
Electric propulsion and direct mechanical propulsion for a 200+ metric ton bollard pull AHTS

Although there is an increasing interest in using electric propulsion for AHTS vessels, most anchor handlers are today built with conventional diesel-mechanic solutions in spite of the obvious fuel saving potential. Contributory may be that charterers awareness of the fuel costs is lower in this segment, and the focus on fulfilling the bollard pull requirement is higher. In addition, as propulsion power increases, so do extra investment costs, which may prevent designers and owners from promoting electric propulsion if they do not get their rightful portion of savings available. An alternative to the full electric solution is the combination of mechanical and electric propulsion systems – the so-called hybrid propulsion system (Figure 6). As the electric and mechanical propulsion systems work in parallel through the gear box, this is also called “parallel hybrid.”

In terms of installation costs, hybrid solutions are more economical than pure electric solutions. In principle, the hybrid solution will gain most of the same benefits in energy efficiency in low load operations, due to the variable speed thrusters and optimal diesel engine operations and at the same time reduce the transmission losses at peak propulsion loads. For these reasons, several new AHTS vessel designs have been based on such hybrid solutions, especially those with high bollard pull.

However, the increased mechanical complexity of such hybrid systems – where the crew must be more active and manually select the optimum operational modes for the prevailing conditions – should not be disregarded. In pure electric propulsion systems, it is much easier for the power management system to optimize the configuration of the power automatically and gain a reduction in consumption of fuel and lower environmental emissions, especially NOx and CO2. With the adoption of electric propulsion by OSVs and now also by AHTS vessels, fuel consumption, emissions and operational costs are being drastically reduced.

Electric propulsion systems make fuel savings possible through the flexible operation of the vessel, even though the system itself introduces new losses in the energy chain. Efforts can, of course, be made to reduce these new losses, but in order to maximize the benefits of electric propulsion, the focus should primarily be on designing a simple, reliable and flexible system.

Control of parallel hybrid propulsion

As the design is optimized for the ship’s operationing profiles and owner’s requests, the control of the parallel hybrid propulsion must also be considered case by case. But in principle, the vessel can be operated in three ways :

6. Hybrid electric and mechanical propulsion for an AHTS.

Hybrid electric and mechanical propulsion for an AHTS
Hybrid electric and mechanical propulsion for an AHTS

7. One approach to control a parallel hybrid propulsion system.

One approach to control a parallel hybrid propulsion system
One approach to control a parallel hybrid propulsion system


8. The 423 metric ton bollard pull vessel Far Samson with hybrid propulsion system; diesel mech: 4 x 6000 kW (4 x 8160 BHP) and diesel electrical 4 x 2755 kW. Total propulsion power : 35900 BHP on main propellers.

– Pure electric propulsion for low-speed manoeuvring, transit and DP.
– Pure mechanical propulsion for tug operations and high-speed transit.
– Hybrid electric and mechanical propulsion, where electrical equipment can be used as a booster for the mechanical propulsion system to maximize bollard pull. One approach, which utilizes all three modes, is shown in Figure 7.

Source : https://new.abb.com

Read more : Profession marine electricianHybrid marine electric propulsion system

Hybrid marine electric propulsion system

The use of electric propulsion in certain vessel types is well-known. In marine applications, nearly all the energy is produced by diesel engines. Using an electric propulsion system, where the energy transmission is electrical and the propulsion and thruster are variable speed electrically driven, fuel consumption can be reduced significantly for many vessel types with environmental benefits. But in some special working conditions, such as dynamic positioning (DP) operation, the load varies substantially, for instance with wave disturbance and weather influence. The sudden load variation is a continuous disturbance of the electric system and the prime movers. Furthermore, to keep to the safety margins of the power generation plants, the average loading of running engines has to be reduced, which increases fuel consumption and environmental emissions.

1. Propulsion and control system layout for a DC grid vessel.

Fast-acting energy storage systems can solve these problems by effectively reducing load power fluctuations in a power system, due to their energy storage capacity. This will smooth sudden changes in power demand, improve the system’s stability and possibly increase the average loading with fewer running engines and thus reduce fuel consumption and maintenance. Super-capacitor technology is one among other solutions, such as batteries, flywheels or possibly in the future superconductors. In this paper, an offshore support vessel (OSV) is chosen as the target vessel. A hybrid converter incorporating supercapacitors will be modeled and simulated in Matlab/ Simulink simulation environment.

2. Structure and outlook of the super-capacitors by Maxell.

Structure and outlook of the super-capacitors by Maxell
Structure and outlook of the super-capacitors by Maxell

An OSV with electric propulsion is equipped with an electric power plant with variable speed drives to control the main propulsion and thrusters. ABB recently released the Onboard DC Grid solution. It adds to the full freedom for integrating and combining different engery sources, including renewables, gas and diesel, and a greater flexibility in placing system components in the vessel design. The main electric propulsion system topology for DC Grid system is shown in Figure 1. The super-capacitor can be used both in AC and DC Grid system to realise the energy storage function and increase the efficiency up to 20 percent.

Super-capacitors technology is a new type of energy storage device used increasingly in industry and automotive applications, such as cars, buses and high-speed trains. Unlike conventional capacitors, super-capacitors have a larger area for storing the charge and closer distance between the electrodes, which is why they achieve much greater capacitance within the same volume.

Compared with the batteries, super-capacitors have several advantages: super-capacitors can be charged extremely quickly, while many battery technologies are damaged by fast charging; supercapacitors can be cycled several hundred thousands of times whereas batteries are capable of only a few hundred cycles. They can deliver frequent pulses of energy without any detrimental effects while batteries experience reduced life-time if exposed to frequent huge power pulses. Super-capacitors can also be charged to any voltage within their voltage rating while batteries operate within a narrow voltage range. On the other hand, batteries can store much more energy than the same size of super-capacitors.

Basic structure of super-capacitor system
Basic structure of super-capacitor system
Buck converter mode
Buck converter mode
Boost converter mode
Boost converter mode
Power control method
Power control method
Improved power control method
Improved power control method
Rules of new DCU system
Rules of new DCU system
Topology of VFD with SC
Topology of VFD with SC
Configuration for diesel electrical OSV
Configuration for diesel electrical OSV
Electric propulsion system modeling
Electric propulsion system modeling
Super-capacitor DC-DC converter model
Super-capacitor DC-DC converter model
Improved control method block
Improved control method block
Simulation results
Simulation results

Fuel consumption savings calculation

The optimum operation point of a diesel engine will typically be around a load of 85 percent of the Max continuous rating (MCR). Moreover, the efficiency level drops quickly as the load becomes lower than 50 percent of MCR, as shown in Figure 18. With the help of the electric system, the mechanical propulsion primer mover is replaced by diesel-electric prime movers that will automatically start and stop as load demand varies. In comparison to a conventional vessel with mechanical propulsion, this enhances the efficiency of the energy usage and reduces the fuel consumption by keeping the average loading of each running diesel engine close to its optimum load point. However, in DP vessel applications, the load variations can be large and rapid. It is impossible to make the generators switch on and off every five seconds as would be the case in the examples above. By using super-capacitors to supply the load variations, and hence let the diesel engines provide the average load, the peak power of the power plant will be reduced, allowing the average loading of the engines to increase to a more optimal point with lower specific fuel oil consumption.

The savings in fuel consumption will depend on many parameters such as actual variations in the load, the average load and the number of prime movers. For example, if one could increase the average loading of the running engines from, for instance, 40 percent to 60 percent, fuel oil consumption would be reduced by more than 10 percent.

Conclusion and further works

In the case studies above it has been shown that the use of super-capacitor for short-term energy storage in a thruster system can effectively limit the power fluctuations seen by the supplying network. The advantages of this are twofold. First, this reduction in power peaks can offset the need for bringing additional diesel engines online, thereby increasing the average loading of each diesel and improving diesel fuel efficiencies. Second, when a diesel engine is loaded and unloaded quickly, the combustion process in the diesel engines is adversely affected.

A reduction in rate at which they are loaded and unloaded will also reduce their fuel consumption significantly. For further work, it is important to quantify possible fuel savings and lifetime costs for larger systems. Investigation into other frequency converter applications found on board ships should also be performed.

Source : https://new.abb.com

Read more : Profession marine electrician; Parallel hybrid propulsion for AHTS

Vetus Stern Thruster Tunnel

Specification :

Vetus Stern Thruster Tunnel
Vetus Stern Thruster Tunnel
  1. Applications: Combine with Bow Thrusters BOW 60, BOW 75 and Bow 95.
  2. Thruster Motor and Prop Sold Separately, Inside Diameter : 185 mm.
  3. Material : Glass fiber Reinforced Polyester.
  4. Item # : 304920.
  5. Brand : Vetus.
  6. Model # : Stern185P.
  7. Shipping Weight : 7.55 Lbs.

Features :

  1. Docking was never this easy.
  2. Combining a Vetus stern thruster with a Vetus bow thruster, will provide an even greater maneuverability of your boat in locks or harbors.

  3. By placing a side-directional thruster in the bow and another one at the transom, docking, sailing away, finding a spot in the lock or marina, becomes child’s play; Even the effects of wind and current can be effectively countered.

  4. Installation of a Vetus stern thruster is simple, the electric motor and other electric components are fitted internally to the transom of the boat; The tunnel and the propeller are installed externally on the transom.

Specifications :

  1. Applications: Combine with Bow Thrusters BOW 60, BOW 75 and Bow 95.
  2. Material: Glass fiber Reinforced Polyester (GRP).
  3. Inside Diameter : 7-9/32″ (185 mm) *
  4. Outside Diameter : 7-23/32″ (196 mm) *
  5. Length 40″

* Both the internal and external diameters may vary slightly from the given dimensions.

Vetus ‘bow thrusters’ can be installed easily as a ‘stern thruster’ by using this G.R.P. thrust tunnel. Due to the special thrust tunnel the electric motor will be inside the vessel. By doing so a reliable protection against influences from the outside is guaranteed. Also the electric motor is good serviceble.
By application of the thrust tunnel is achieved that :
• The propeller is shielded so the risk of inflict of damage and/or injury is highly diminished.
• The flow of the water is optimized so a high thrust will be obtained.
This installation instruction explains only that part of the installation that differs from the installation instruction going with the bow thruster. So consult for the installation of the entire stern thruster also the relevant bow thruster instruction.


For operation of the stern thruster consult the owners manual of the installed bow thruster.


The G.R.P. thrust tunnel requires no maintenance.


For overall dimensions, consult the drill pattern.


The reliability of the stern thruster is entirely dependent on the quality of the installation. Nearly all problems are caused by faults or inaccuracies which occur during the installation. It is therefore of utmost importance to follow and check the points mentioned in this manual.
Note : The numbers in bold type point to the drawing numbers.

Positioning of the stern thruster

  1. When choosing the location for the stern thruster take in account that for an optimum result the centerline of the thrust tunnel must be at least ‘X’ mm below the the waterline. Consult the drill pattern for ‘X’. The electric motor must always be well clear from the maximum bilge water level. Consult the drill pattern for maximum allowable hull thickness.

  2. The stern must be level. Otherwise it must be filled out with a spacer. Note that the total thickness must be less or equal than the maximum allowable thickness of the stern.

  3. In case that the available height at the stern is insufficient for the installation of the stern thruster a sloped surface can be made to install the stern thruster. Than keep in mind that the thrust tunnel must be protected against the forces caused by the water flow during normal cruising.

  4. Installation in the bottom of the vessel is not recommended. The thrust tunnel is not designed to withstand the forces of the water flow during normal cruising. At the same time also the normal propulsion is highly slowed down.

Installation of the thrust tunnel

  1. At the place of installation of the stern thruster attach the drill pattern at the outside and mark the holes. IMPORTANT: The centerline of the drill pattern must be precisely horizontally and at least ‘X’ mm below the waterline.
    For checking purposes drill first a small hole at the location of the centre point of the flange. On the inside checking the available space for flange and motor can now be carried out easily.

  2. Make the holes, dependent of the material of the ship’s hull by means of a drill and a jigsaw or with an oxy-acetylene cutter. Make sure that the holes are free of burrs.

  3. Apply a sealant to the mounting surface of the thrust tunnel (a polyurethane sealant e.g. Sikaflex 292) and position the thrust tunnel onto the hull.

  4. Install the thrust tunnel with bolts, nuts and washers. These parts are not supplied, but must be ordered separately. Consult the drill pattern.

Bolt length depends on the hull thickness.

Installation of the ‘bow thruster’

The ‘bow thruster’ must be installed in accordance with the relevant bow thruster instruction.

Check whether the distance between the tips of the propeller blades and the inside of the thrust tunnel is exactly the same all along the periphery.


Vetus Stern Thruster Tunnel Drawing
Vetus Stern Thruster Tunnel Drawing


Maxpower Stern Thruster Tube Adapter

Specification :

  1. For Max Power Models CT 35, 45.
  2. 5″ (125mm) Diameter.
  3. Item # : 300208.
  4. Brand : Maxpower.
  5. Model # : 315389.
  6. Shipping Weight : 25.00 Lbs.

Features :

  1. Manufactured from fully isophtalic resin, Max Power’s range of stern adaptors are SMC molded (sheet molding compound) in a male / female steel mold
    • This ensures perfect resin fiber ratio and exceptional reproduction of form.
  2. A Stern Thruster Tube Adapter is used with tunnel thrusters to allow increased maneuverability at the stern in conjunction with a bow thruster.
  3. Adapters mount to the transom of your boat.
Maxpower Stern Thruster Tube Adapter Drawing
Maxpower Stern Thruster Tube Adapter Drawing

Side-Power Stern Thruster Tunnel

Specification :

  1. Designed for SE30 and SE40 Side-Power Thrusters.
  2. Material : Composite, 30% Stronger than Fiberglass Stern Tunnels.
  3. Ready Bored, with Extension Harness for Control Box.
  4. Item # : 304834.
  5. Brand : Side-Power.
  6. Model # : SM90124i.
  7. Shipping Weight : 4.50 Lbs.

Features :

  1. Composite Stern Tunnel for SE30 and SE40.
  2. Ready bored, with extension harness for control box.
  3. Stronger and more accurate stern tunnels with added safety features.
  4. 30% stronger than fiberglass stern tunnels.


To achieve maximum effect, reliability and durability from your Sidepower Sternthruster, a correct installation is veryimportant. Please follow the instructions carefully, and make sure that all checkpoints are carefully controlled.

Make sure that there are enough space both inside and outside the transom of the boat.

Installation Side-Power Stern Thruster Tunnel
Installation Side-Power Stern Thruster Tunnel
Installation table Side-Power Stern Thruster Tunnel
Installation table Side-Power Stern Thruster Tunnel

Additional considerations for positioning of stern thruster.

  1.  Make sure that the stern-tunnel does not disturb the waterflow under the hull.
  2. Ensure that when installed the thruster does not foul exisiting equipment inside the boat like steerage links etc.
  3. It is essential that the motor is supported so that the total weight is not on the tunnel alone.
  4. Make sure that the water flow from the thruster are not intereferred to much by sterndrives, trimtabs etc. as thiswill reduce the thrust considerably.
  5. It is possible to mount the tunnel off the boat’s centre line if necessary.
  6. If the stern thickness is to much for the thruster in question you can easily remove material in the necessary areato fit the thruster. The stern thickness even here will never have to be less than the max. measurement given asmax. stern thickness.


  1. Once the place for the installation has been decided, hold the tunnel in place in the horizontal position and mark the bolt holes. Remove the tunnel and it is then possible to calculate and mark the centre.

  2. It is important that the tunnel flange sits flush on the transom. If this is not case, then the fitting area on the transom will have to be worked to ensure a snug fit. PS ! Take care with grinders as it is very easy to remove to much fibreglass At this time, cut out the centre hole and the transom to the same internal diameter as the tunnel flange and drill the bolt holes. Before actual fitting the stern tunnel, we recommend that the prepared area is sealed with a gelcoat or similar to ensure there is no water ingress.

  3. Before fitting the tunnel to the transom, install the gear leg to the tunnel as described in the thruster installation manual. We recommend that you fit the oil feed pipe also before the tunnel is bolted to the transom. Special installation points described on page.

  4. When fitting the tunnel, ensure that there is ample sealant (Sikaflex or similar) in the sealing tracks of the tunnel flange and around the bolts to make a water tight fitting (see FIG. 2&3). Bolts, washers and nuts are not included as they will vary depending on the transom thickness. We recommend A4 stainless with A4 lock nuts and A4 washers of a large diameter on both outside and inside. Bolts diameter (stainless steel) :
    ø 6mm or 1/4” for SE 40 & SE 60.
    ø 10mm or 3/8” for SE 60/SE 80/SE 100/SE 120/SE 130/SE 150/SE 170/SE 210/SE 285, SH 100/SH 160/SH 240/SH 300.
    ø 12mm or 1/2” for SH 420/SH 550.

  5. The electromotor must have a solid support so that the weight can not cause a twisting action on the tunnel (see FIG. 4).

  6. Refer to the installation manual for the recommended thruster fitting.
Bolt on installation of Side-Power Stern Thruster Tunnel
Bolt on installation of Side-Power Stern Thruster Tunnel


  1. Cut of the bolting flange on the stern-tunnel.
  2. Grind off the gelcoat both inside and outside theremaining “tube” atleast 10 cm down on the“tube” (see FIG. 5).
  3. Offer the stern tunnel to the desired position onthe transom and mark around the tube.
  4. Cut the marked hole in the transom of the boat.
  5. Grind off the gelcoat on the transom of the boat inan area of atleast 10 cm / 4” around the hole, bothoutside and inside (see FIG. 5).
  6. Offer the stern tunnel to the transom in the desiredhorizontal position, then bond to the transom withmulti layers matt both inside and outside (see FIG.6). Take care not to reduce the internal diametermuch, as this will make it more difficult to mount the thruster.

  7. Apply gelcoat or similar on all bonded areas.

  8. Install the gear leg on the stern-tunnel as de-scribed in the installation manual for the thrusterbut fit the oil feed pipe first. Special installation points described on page 7 ofthis manual.
  9. The electromotor must be sturdily supported sothat the weight-arm tension from the motor weightare not applied only on the tunnel (see FIG. 4).

  10. Basic installation of the flexible coupling, motorand electrical installation are described in thethruster manuals.

    Mould installation of Side-Power Stern Thruster Tunnel
    Mould installation of Side-Power Stern Thruster Tunnel