Curious About Stabilization Systems?

Yes all fin sizes can be freely modified in the upper back part of the fin. Whenever it’s necessary to adapt the fin, it’s recommended to remove as little area as possible. Area removed equals in loss of performance. Step up in fin size could be a option to ensure performance, if a large portion of the adaptable zone needs to be removed.

Humphree currently have 0,6m², 0,8m², 1,0m2, 1,3m² and 1,5m² sized fin

In case of hitting an object straight ahead, the fin is designed with a 'fail safe' approach and the break off force is presented as "Grounding force", please se the following document for more details: ''021564 INSTALLATION DRAWING SU553 SU563 CHOCKFAST ENG''. If the force is less than the break off force, it's important to inspect the fins, servo unit, seals and hull for damages.

Humphree have currently two diffrent servo units for the diffrent finsizes, the finservos share the same footprint and size. Servo unit 553 (SU553) for 0,6-0,8m² fins, and Servo unit 563 (SU563) for 1,0-1,5m² fins. Both servo types are run on 24 VDC.

No. Batteries are required because of the servo unit's ability to regenerate power. It's not allowed to connect the system directly to a generator or a charger without a battery in between. Se 031142 Technical Specification Stabilizing Fin for more details and guidelines.

Humphree stabilizing fins reduce roll by generating hydrodynamic lift forces on both sides of the vessel. The fins are actively controlled by a high-speed motion control system that continuously measures vessel movement using gyros and motion sensors.

Humphree electric fin stabilizers use electrically driven actuators instead of centralized hydraulic power systems. Humphree’s electric stabilization systems eliminate hydraulic piping and oil handling, which improves reliability and reduces environmental risks onboard.

It depends on fin size and sea state. Zero speed stabilization at anchor has the highest power usage. Full stroke (max power) RMS current consumption varies between 43-105A(24V) for each servo unit depending on fin size (0,6-1,5m2). Underway stabilization RMS current consumption normally varies between 5-40A(24V) for each servo depending on fin size and sea state.

Humphree fin installs need to be powered through a battery bank due to the fact that the fins regenerate power. Either a separate or an existing battery bank is needed. Size of power bank depends on how long time the fin system should be able to run without charging on. As an example of a separate battery bank: For a twin fin install we recommend to have from 150Ah to 480Ah (24V) battery capacity depending on the chosen size of fin. This recommendation is based on running the system without charging up to 1,5hour with a battery discharge from full charge to a minimum charge level of 50%. Normally the added generator load is not a concern as the system is very efficient.

A gyro has a constant sound as it is always spinning when it is on. A fin system have a sound that varies from no sound at all when there are no waves, to a similar sound level as a gyro when the fin moves to dampen motions. Fins are not noisier but has a variable sound pattern due to their working principle. For many boat owners, this variable and often quieter sound pattern makes fins the more comfortable choice.

This is individual of course but we would say yes, most boat owners sleep comfortably with the stabilizing fins running. We also have a zero speed mode that is called “soft”, this mode fits well when anchored in sheltered and calm water, energy consumption is minimized together with noise level and depending on installed battery bank size generators can be turned off to get overall sound level reduced to a minimum provide better sleep environment.

Fins and gyros are both offering stabilization, although in two different ways with peak performance at different operation conditions. Choosing which system is optimal for you is thus a matter of personal preference. A gyro offers magnificent stabilization at zero speed. However, when vessel speed increases the vessel gets stiffer, thus making it harder to dampen. This is where the two system differs, while the dampening force from the fins increases exponentially with vessel speed, the stabilizing moment from the gyro stays constant and since a stiffer vessel is harder to dampen, the absolute dampening effect of the gyro reduces.

If you are looking for zero speed stabilization, gyros are to prefer but fins are not far behind when they are dimensioned correctly for the boat size.

If you are looking for all speed stabilization, fins are to prefer as the gyro effect is only noticeable at rest or really low cruising speed.

The combination of gyros and fins is usually your optimal choice, ideally when synchronized by one control system. Separate Gyro and Fin stabilization systems can in certain conditions be conflicting each other in challenging sea conditions.

The latter would also allow you to size down the two systems resulting in weight savings, and potentially cost savings. Please have a look at the below analysis of a stabilization system for a standard 60ft motor yacht and the roll damping effect of the different systems plotted over vessel speed. Reach out to your closest Humphree Dealer for further discussions of your specific needs!

A gyro has a constant sound as it is always spinning when it is on. A fin system have a sound that varies from no sound at all when there are no waves, to a similar sound level as a gyro when the fin moves to dampen motions. Fins are not noisier but has a variable sound pattern due to their working principle.

A fixed Humphree fin increases coarse keeping on high speed vessels. Our streamlined fin profile has low drag and high coarse keeping ability. Most often used on water jet boats.

A base ventilated fixed fin is for boats that need coarse keeping at speeds above 40 knots. The fin has a flat aft and is installed flush with the transom. The fin ventilates above ventilation speed and does not cavitate keeping a wet surface on the side to keep the boat going straight. If you were to use a normal fin at speeds above 40 knots the entire fin may cavitate and all “grip” is lost.

Due to an optimized Fin Geometry with an aspect ratio chosen the generate the most amount of zero speed stabilization without compromising the performance at speed. Humphree improves low-speed stabilization through:

Optimized fin geometry

Rapid actuator response

Advanced control algorithms

Integrated interceptor technology on some vessels

The system predicts and reacts quickly to roll motion, allowing stabilization performance even during slow cruising, maneuvering, or zero-speed conditions.

The control system is the core intelligence of the stabilization package.

It performs several technical functions, such as:
Measures vessel roll, pitch, yaw, and acceleration
Processes sensor data in real time
Calculates optimal fin angles
Commands actuator movement with high frequency updates

The control system can handle any type of combination av Humphree products and optimizes the ride comfort in all speed conditions.

Several technical parameters must be evaluated when sizing and selecting a fin stabilization system:

Vessel characteristics
Length overall (LOA)
Beam
Displacement
Center of gravity
Hull type
Operational profile
Typical cruising speed
Sea state conditions
Passenger comfort requirements
Offshore vs coastal operation
Stabilization requirements
At-anchor stabilization
Underway stabilization
Roll reduction percentage target
Installation factors
Available hull space
Structural reinforcement needs
Electrical power availability
Drag and fuel efficiency impact

Humphree engineers typically perform vessel motion analysis and CFD/hydrodynamic calculations to determine the correct fin size and actuator capacity.

Humphree have 3 diffrent interceptor deployment lengths. The Lightning interceptors, X- interceptors, H and HA- interceptors share deployable blade length of 50mm. The extended HE and HAE-series interceptors have deployable blade length of 75mm and the Largest HLS-series have 110mm of deployable blade length.

The Lightning interceptor have the servo integrated in the interceptor itself. The X, H, HA, HE and HAE-series currently shares the same servo, servo unit 501 (SU501). The HLS have a bigger and more powerful servo unit 530 (SU530).

The Servo unit 501 have a IP67 classification.

All interceptor models but the X-series and Lightning interceptors can be customizeable to fit most transoms, however the Lightning Interceptors have a chine version, that is available in a starboard and port version and can be modified depending on the chine angle.

+- 1mm planarity. Adapt the hull surface or grind on the hull surface flat if needed. It's also possible to grind on the optional mountingplate.

No problem, check out our custom interceptors here and give us a call and we will explain what can be done. We have over 1000 custom interceptors for all types of hull shapes. A slight curve (a few mm per meter) will be just fine with our standard off the shelf products but if the interceptor needs customization we can choose from our five Interceptor families H, HA, HE, HAE and HLS where each family has a width from 300mm to 1500mm and custom shape them to find the perfect match to your vessel. 

Depending on your hull material and/or position of the interceptor the guidelines in the installation manual should be sufficient to understand the installation. If you have more questions our application team can guide you through the process, we are happy to help.

The sensors in the control unit needs to be set up orientated to fit how the unit is installed in the boat and the trim and list needs to be set to zero when the vessel is laying flat.

Please contact us to become a part of the Humphree family. You can read about the customer journey here to understand how we can take care of you and help you make your boat even better.

Humphree interceptors generate lift by deploying a vertical blade downward from the transom into the water flow beneath the hull. This “intercepts” the water flow and creates a high-pressure zone ahead of the blade, producing hydrodynamic lift directly on the hull.

Traditional trim tabs work differently:

They use angled horizontal plates
Lift is generated by deflecting water downward
Larger deployment angles typically create more drag

Humphree interceptors are generally more efficient because:

Smaller blade movement creates significant lift
Drag is lower
Response times are much faster
Dynamic stabilization is more precise

The vertical deployment principle allows Humphree systems to react in under 0.7 seconds for real-time trim and roll correction.

Humphree interceptor systems use electric servo actuators instead of hydraulic cylinders and pumps.

Humphree systems also position servo motors inside the hull using watertight cable connections, improving reliability and protecting critical components from seawater exposure.

The Humphree HCS-5 system is the integrated ride-control platform that manages interceptors, sensors, and stabilization algorithms.

The system continuously measures:

Roll
Pitch
List
Yaw
Vessel acceleration
Steering input

Using this data, the controller automatically adjusts interceptor blade deployment in real time to optimize vessel behavior.

Key functions include:

Automatic Trim Control
Automatic List Control
Coordinated Turn Control
Roll Stabilization
Pitch Stabilization

The system uses high-speed brushless servo motors and motion sensors to provide instant response to hull dynamics.

Humphree interceptors are particularly effective on planing and high-speed vessels because lift generation increases with water flow velocity beneath the hull.

At higher speeds:

Water pressure under the hull rises significantly
Small interceptor deployments create large lift forces
Dynamic corrections happen almost instantly

Humphree specifically designs interceptor systems for:

Performance RIBs
Patrol boats
Ferries
Sportfishers
Military craft
High-speed yachts

The fast actuator speed allows continuous stabilization during:

Rapid acceleration
Sharp turns
Wave impacts
Speed transitions
Humphree states the systems are capable of operation on vessels reaching up to 70 knots.

Selecting the correct interceptor system requires detailed analysis of the vessel’s hull geometry, operational profile, and hydrodynamic behavior.

Key engineering parameters include:

Vessel dimensions

Length overall (LOA)
Beam
Displacement
Draft

Hull configuration

Chine geometry
Transom shape
Waterjets or sterndrives
Tunnel hull arrangements

Operational profile:

Cruising speed
Top speed
Typical sea state
Load distribution

Performance objectives

Fuel efficiency improvement
Roll reduction
Pitch damping
Passenger comfort
Tactical maneuverability

Humphree offers multiple interceptor series including

X-Series
H-Series
HA-Series
HE-Series
HL-Series

With blade sizes ranging from approximately 300 mm to 1500 mm depending on vessel size and application.

It depends on vessel displacement, center of gravity and the stabilizer components you choose. As a rule of thumb: HIG5 + interceptors is ideal for boats ~40–50 ft up to ~18 tonnes. Adding fins typically extends suitability to roughly 60 ft, depending on fin size. We always run a prediction for your specific boat to size the system correctly.

Yes. Retrofit is possible but requires structural calculations and may need hull reinforcement to absorb gyro and fin loads. If you already have a Humphree system, software and possibly hardware, updates will be needed depending on your configuration.

Available to boatbuilders late 2026. Retrofit availability follows shortly after. For schedule details, contact our product team.

Pricing varies by configuration. No public list price yet; contact sales for a tailored quote when sales to end customers begin.

Increasing numbers of builders will install it next year. We recommend visiting a boatbuilder installing the system. At Cannes you can see an installation on a Cranchi, they are first to fit it on production boats.

Ask your boat supplier to include it or to contact us if it’s not yet on the option list.

Initial launch: HIG5. We will expand the range with larger sizes over coming years.

A gyro alone is effective mainly at very low speeds. We strongly recommend combining it with at least one other stabilizer (fins or interceptors) for full-speed-range performance.

Humphree systems will be available late 2026; coordinate installation timing with your boatbuilder.

Humphree offers a global service network. See Humphree.com for local support contacts.

Remote support lets a Humphree technician connect via the internet to diagnose, update and support your system without onboard visits.

A vacuum reduces internal friction, lowering energy required to spin the flywheel to high RPMs.

No, all service operations can be performed in situ.

Integration gives combined stabilization across speeds and maneuvers: components work together for better, seamless control.

Combined fins + gyro deliver stabilization across the entire speed range. Gyro + fins excel at low speed and at rest; fins maintain high performance as speed increases. A combined system also lets you choose a smaller, lighter gyro, reducing weight and complexity.

The system integrates with Volvo EVC as Volvo interceptors do. The complete integrated solution is sold by Humphree; individual Volvo components are not sold separately through us.

All components communicate and coordinate. The system automatically uses the best combination for each condition e.g., gyro + fins at rest or low speed, fins + interceptors at higher speeds.

Suitable for all hull types: displacement through planing. Size suitability depends on the chosen component combination (see sizing guidance above).

HIG5 significantly improves stabilization at anchor and at very low speeds, complementing fin performance underway.

Humphree has more than a decade of proven, coordination of fin and interceptor stabilization together. That integration expertise uniquely positions us to deliver best-in-class combined systems that include gyros for seamless, high-performance stabilization across all conditions.

Most planing and semi-planing powerboats and yachts can be equipped with interceptors, gyro, fins or a combination of all. Each installation should be evaluated individually to ensure the system delivers the intended effect.
 
If there isn’t enough flat mounting area available (due to swim platforms, ladders, or similar structures), installing interceptors can also be challenging.

The effect depends on the hull, load, and usage of the boat, but on planing powerboats, the difference is often noticeable. Interceptors significantly reduce the time to get on plane and decrease bow pitch by 10–30%. The smoother motion through the water also often reduces fuel consumption by 5–15% at cruising speed while improving yacht performance.

Fins primarily do not affect top speed but reduce rolling at standstill or very low speeds. This rolling can decrease by 50–90% depending on current sea conditions.
 
Our gyro works in concert with interceptors and fins to deliver the ultimate balance at sea. Spinning at many thousand revolutions per minute, the gyro generates a relentless force that overpowers the sea itself. Primarily designed for zero-speed and low-speed operations, it effectively eliminates roll.

In a Humphree system, where interceptors, gyro and fins work together as one integrated stabilization system, both pitch and roll are optimized, providing a smoother and more comfortable onboard experience, both at rest and at high speeds.

Yes, Humphree marine stabilization systems can be integrated into the boat’s existing multifunction display (MFD). Alternatively, a separate control panel can be used.

All appendages that interfere with water flow or affect the motion of the boat create drag. Interceptors thereby create local drag when lowered into the water. At the same time, they lift the stern and change the angle of the hull hits the water.

Interceptors improve balance and decrease the total resistance despite the small drag caused by the interceptor blades, an improved balance actually decreases total resistance despite the small drag caused by the interceptor blades.

Both interceptors and traditional trim tabs serve the same basic purpose: to lift the stern and optimize the boat’s trim angle. Trim tabs consist of horizontal plates that adjust the angle, often hydraulically. They usually require relatively large movements to be effective and respond more slowly compared to modern alternatives.

Interceptors, on the other hand, consist of narrow, vertical blades that are lowered just a few millimeters into the water flow at the stern. Instead of acting like a wing, they create local pressure directly at the stern, generating lift. Because the movement is minimal and electronically controlled, the system can operate extremely quickly—often adjusting multiple times per second. Compared to traditional trim tabs, interceptors can be up to 25% more efficient.

So while both trim tabs and interceptors lift the stern, interceptors do so with higher precision and faster response. The result is a continuously optimized trim angle and a boat that feels more balanced and stable across the entire speed range, even in rough seas.

An integrated Humphree system uses significantly less power than many expect. Since the blades move very little and the system is electronically efficient, it often draws only a few amperes during the brief periods when adjustments are made. On a typical planing powerboat, the system can run directly from the boat’s existing 12 V or 24 V battery system.

However, when retrofitting a stabilization system, it may be necessary to review the vessel’s existing electrical supply and, if required, upgrade or supplement it to ensure sufficient capacity.

Overall, battery capacity should be sized according to the vessel’s total electrical demands, with the stabilization system representing only a minor share of the overall consumption.

Interceptors are mounted directly on the transom and are partially recessed into the hull to reduce drag and protect against impacts. Installation requires professional service, but no major hull modifications are needed; mounting points for the interceptors themselves are created or adapted during installation.

Yes. Fins are mounted through the hull and require carefully executed through-hull fittings. The installation is a well-established marine technique and uses seals and construction designed to ensure long-term durability and safety. A naval architect should verify that the hull structure can withstand the forces generated by the fins during operation.

A Humphree system is designed for the marine environment and is suitable for both freshwater and saltwater. All electronic components are sealed and corrosion-protected to withstand harsh conditions. The system is built for long-term durability and is designed to perform reliably throughout the lifetime of the boat, provided normal maintenance practices are followed.