What is the best marine autopilot system you can buy in 2021? That’s exactly what we look into today.

We have taken 5 top-rated autopilot systems covering a range of configurations. Providing an in-depth analysis of each, we aim to bring you the definitive answer on which is the best option for you.

For our findings at a glance, just head to the table below. For a comprehensive review of each marine autopilot rig, plus a dedicated buyer’s guide, keep on reading.

Best Marine Autopilot – Top 5

Best marine autopilot reviews

Using the aforementioned autopilot rating criteria, 5 of the best marine autopilots have been selected for review. Among these 5 models, the best marine autopilot is singled out.

1. TOP PICK FOR SAILBOAT: Raymarine EV-100 P70 Marine Autopilot

Our top pick is the EV-100 P70 from the ever reliable Raymarine. This is a fully-enclosed wheel-drive pilot pack, (cockpit-mounted) marine autopilot designed to run either a mechanically-steered or hydraulic-steered sailboat.

It is designed for precision monitoring of course direction as well as the yaw, roll, pitch, and heading of the marine vessel so as to detect and immediately correct off-course deviations.

Regarding installation, the water-proof housing of this model allows it to be installed either below or above the deck.

This model is part of the cockpit marine autopilots manufactured by Raymarine Marine Electronics, a subsidiary of the U.S-based FLIR Systems.

This model uses the patented and proprietary Evolution (EV) autopilot intelligence that eliminates the need for calibration as the autopilot can learn and adapt to the vessel steering characteristics of the human pilot.

That is the steering capability of the model evolves with continued use, and this ultimately allows it to autonomously steer the boat through a pre-routed course without user adjustments. Its model number is T70152.

This compactly-designed easy-to-install model weighs about 14pounds, and its packaging is a perfect cube with equal height, width, and height dimensions with each measuring 15.8inches.

It is shipped as a single package that contains 4 separate boxes that house the sensor core, wheel unit, p70 controller unit, and ACU-100.

This model is designed to be used in small and medium-sized sailing boats. According to its manufacturer, it should be used in wheel-steered sailboats whose displacement capacity does not exceed 16,000pounds.

The wheel pilot pack has the following main components; an EV-1 sensor core, wheel drive, p70 control head, ACU (Actuator Control Unit)-100, and an Evolution cable kit.

The EV-1 sensor core supports mechanical and hydraulic steering with its data sensors relaying data to the ACU-100. This sensor core is connected to the rate gyro unit.

The Actuator Control Unit handles and determines the movement of the wheel drive. This ACU is connected to the drive unit and the rudder reference unit. The ACU-100 provides an interface between the wheel drive and the 9-axis sensor and EV-1 course computer.

The wheel pilot of this wheel drive is fully-enclosed so as to make its installation and use simple, as well as ensuring that the user achieves maximum autopilot performance from this model.

The system fits well into most types of steering wheels found in wheel-steered sailboats, with its simple yet robust clutch engagement mechanism allowing for the drive unit to be disengaged when the boat is on standby.

The wheel pilot also features an in-built motor. The average speed, as measured by revolutions-per-minute (rpm), of this wheel drive is 9rpm and can handle a thrust of 30Nm.

It is connected to the other components using an STng connection along with an NMEA 2000 (which comes with an adapter cable).

The Evolution cabling kit features a 0.4meters long ng power cable, a 5-meter long SeaTalk-ng (STng) backbone cable, a 0.4-meter long STng spur cable, along with a 5-way STng connector block, 2 STng Terminator pieces, and 2 STng T-piece connectors.

The first terminal of the connector block is connected to a 12-volt power supply, and the other 4 terminals allow this power to be distributed to all components of this marine autopilot.

Its p-70 control head features a large LCD display with 8 control buttons located directly below it, along with the patented LightHouse user interface.

This push-button operation controller features the menu, auto, standby/off buttons, along with 4 degree-adjustment buttons; the -1, +1, -10, and + 10 degrees adjustment buttons.

Its advanced LED back-light is designed to deliver vibrant color and superb contrast while drawing the least amount of power. The wide viewing angles of this LED display allow the user to see the readings from acute viewing positions.

The Raymarine EV-100 p70 benefits from a 36-month warranty. It also comes with several instruction manuals that describe the operations of the different core components as well as how to set-up this marine autopilot.

Bottom-line

The Raymarine EV-100 p70 is a fully-enclosed, high-performance wheel-drive pilot pack that can be mounted in the cockpit.

Featuring a waterproof housing that allows the unit to be installed either below or above the deck; the operational design and circuitry of this marine autopilot also allows it to run either a mechanically-steered or hydraulic-steered sailboat.

Talk about versatility, that’s exactly what you get here.

This superior design quality, good core pack build, easy-to-use control head, and the high cost-performance ratio of the Raymarine EV-100 P70 Wheel-Pilot Pack makes it, in our opinion, the best marine autopilot in our top 5 round-up.

2. BEST FOR MOTORTBOAT: Garmin 101-7000-00 Gold-Marine Autopilot System

This complete kit is an electro-hydraulic marine autopilot built for cockpit-mounting, upon which it allows for remote steering along with speed control for small gasoline-powered outboard motor-boats.

It is designed to provide hands-free, worry-free operation of motorboats whose power rating does not exceed 20 horsepowers (HP).

Like all good autopilot systems, the Garmin is able to provide precision monitoring of course direction as well as the yaw, roll, pitch, and heading of the motorboat.

Off-course deviations are detected and corrected as soon as they occur. Furthermore, to aid in the overall reliability of course direction, the unit can be connected to an external GPS receiver using NMEA 0183.

As the name suggests, this model is manufactured by Garmin Limited.

The system can use a Garmin-GPS or an NMEA-0183 compatible GPS system to navigate around selected way-points, and this ultimately allows it to autonomously steer the boat through a pre-routed course without user adjustments.

This compactly-designed easy-to-install model weighs about 30pounds, and its overall dimensions are; 18inches long, 10inches wide, and 10inches high.

The marine autopilot kit comes complete with a hydraulic unit, hand-held controller, deck-mount, battery cable, compass ball, steering cylinder, and steering hose. It is also shipped along with its mounting hardware pack.

This particular model is designed to be used in small and medium-sized motorboats. Its manufacturer states that the maximum power rating for the boat should be 20HP.

This model is designed for remote steering, and its standard wired controller is built to be either panel-mounted or used independently as a portable hand-held remote.

The entire unit needs to be powered by 11.5-14volts direct-current electrical power, and the autopilot can work well in an operating temperature that ranges from -20 to 120 degrees Fahrenheit.

Its easy-to-maintain electro-hydraulic unit has a compact design that features Gold-Pico connectors that handle the 4 plug-in connections.

It uses BioSOY as its hydraulic fluid, and the unit is shipped alongside a bottle of BioSOY fluid.

Its compass ball contains a fluxgate along with a standard rate gyro. Its resolution is 0.25degrees, which is quite sensitive and can allow for very precise helm corrections so as to ensure that the motorboat accurately follows its selected route. It also features an 18feet cable and can be operated via the hand-held remote.

This model has a waterproof enclosure that is surface-mountable. It also comes with a back-lit silicon pad along with a splitter box that allows for 2 or more remote controls to be used to operate the marine autopilot.

It also comes with several instruction manuals that describe the operations of the different core components as well as how to set-up this marine autopilot.

Bottom-line

The Garmin 101-7000-00 Gold-Marine is an electro-hydraulic marine autopilot built for cockpit-mounting.

It allows for remote steering along with speed control for small gasoline-powered outboard motor-boats whose power rating does not exceed 20 horsepowers (HP).

If you’re looking for an autopilot system for a boat of this size or below, this is the model that we recommend.

3. Lowrance 000-11748-001 Marine Autopilot

This is a complete kit of an electro-hydraulic marine autopilot that is designed to be mounted in the cockpit from where it can operate a hydraulically-steered vessel.

It is well suited for boats measuring less than 30-feet in length, and whose design feature a single-outboard setup.

It is designed for precision monitoring of course direction as well as the yaw, roll, pitch, and heading of the motorboat so as to detect and immediately correct off-course deviations.

It comes with a new proprietary interface dubbed Lowrance SmartSteer that allows it to handle both the hydraulic steer of the outboard motor along with the electric-steer of the MotorGuide-Xi5 Pinpoint trolling motor.

It can be connected to an external GPS receiver using NMEA-2000. This model is manufactured by Lowrance.

It can use an NMEA-2000 compatible GPS system to navigate around selected way-points, and this ultimately allows it to autonomously steer the boat through a pre-routed course without user adjustments.

This compactly-designed easy-to-install model weighs about 12pounds, and its overall dimensions are; 18inches long, 8inches wide, and 10inches high.

This marine autopilot comes with a NAC-1 Autopilot Computer, PUMP-1 Hydraulic Pump, Point-1AP GPS Sensor, NEMA-2000 Starter Kit, and a Hydraulic Fitting Kit.

This model is designed to be used in boats whose length does not exceed 30 feet. The entire unit needs to be powered by electrical power whose voltage rating is 12volts.

The NAC-1 Autopilot Computer is the course computer of this model, and it not only steers the boat but also ensures that the drive-unit motor runs properly.

The PUMP-1 is a 0.8-liter hydraulic pump that is compatible with a standard SeaStar manual-helm pump.

Also, there is a Point-1AP that serves as both the GPS and heading sensor of the autopilot; and is allows the boat to accurately follow the selected route while allowing for rapid updates of the boat position along its course.

Its hydraulic fitting kit comes with hoses, T-connectors, and oil. This model comes with a high-definition system (HDS) display.

Also, using only a single touch on the control panel, can save trails that the boat has previously navigated. It also allows for route creation using waypoints, as well as allows the boat to perform repeat turn patterns.

This model features a Virtual Rudder Feedback (VRF) which simplifies the process of pilot installation as it eliminates the need for installing a rudder-position sensor.

It comes with a 24-month warranty, which is supported by the special Lowrance Service program It also comes with several instruction manuals that describe the operations of the different core components as well as how to set-up this marine autopilot.

Bottom-line

The Lowrance 000-11748-001 is a high-quality, high-performance electro-hydraulic marine autopilot (designed for cockpit mounting).

It can operate a hydraulically-steered vessel that 30 feet or less in length, and whose design features a single-outboard setup. Highly recommended.

4. Raymarine (T70154) Pilot Ev-100 P70R Power Pack

The EV-100 P70R Power Pack is a fully-enclosed high-quality, high-performance cockpit-mounted electro-hydraulic marine autopilot that comes with a 0.5-liter hydraulic pump.

The eagle-eyed among you will notice that part of the unit is a newer version of what’s included within our top-rated pick, (here you get the P70R rather than the standard P70).

The total kit is well suited for hydraulically-powered boats whose design features a single-outboard setup.

It is designed for precision monitoring and can detect and immediately correct off-course deviations.

Just like the Raymarine EV-100 P70, this P70R model features a waterproof housing that allows it to be installed either below or above the deck.

This model is part of the cockpit marine autopilots manufactured by Raymarine Marine Electronics, a subsidiary of the U.S-based FLIR Systems.

This model uses the patented and proprietary Evolution (EV) autopilot intelligence that eliminates the need for calibration as the autopilot can learn and adapt to the vessel steering characteristics of the human pilot.

That is the steering capability of the model evolves with continued use, and this ultimately allows it to autonomously steer the boat through a pre-routed course without user adjustments.

This compactly-designed easy-to-install model weighs about 14.9pounds, and its packaging is a perfect cube with equal height, width, and height dimensions with each measuring 15.8inches.

It is shipped as a single package that contains 4 separate boxes that house the sensor core, hydraulic pump, P70R controller unit, and ACU-100.

This model is designed to be used in small and medium-sized hydraulically-steered sailing boats.

This power pack has the following main components; an EV-1 sensor core, 0.5-liter hydraulic pump, P70R control head, ACU (Actuator Control Unit)-100, and an Evolution cable kit.

The EV-1 sensor core supports hydraulic steering with its data sensors, including solid-state sensors, relaying data to the ACU-100.

This sensor core is connected to the rate gyro unit. The Actuator Control Unit handles and determines the movement of the helm.

This ACU is connected to the drive unit and the rudder reference unit. The ACU-100 provides an interface between the control head and the sensor and the EV-1 course computer.

Just like the Raymarine EV-100 P70, the Evolution cabling kit of Raymarine EV-100 P70R features 0.4meters long ng power cable, a 5-meter long SeaTalk-ng (STng) backbone cable, a 0.4-meter long STng spur cable, along with a 5-way STng connector block, 2 STng Terminator pieces, and 2 STng T-piece connectors.

The first terminal of the connector block is connected to a 12-volt power supply, and the other 4 terminals allow this power to be distributed to all components of this marine autopilot.

Its P70R control head features a large LCD display with 8 control buttons located directly below it, along with the patented LightHouse user interface.

This push-button operation controller features the menu, auto, standby/off buttons, along with 4 degree-adjustment buttons.

Its advanced LED back-light is designed to deliver vibrant color and superb contrast while drawing the least amount of power. The wide viewing angles of this LED display allow the user to see the readings from acute viewing positions.

The Raymarine EV-100 P70R benefits from a 36-month warranty. It also comes with several instruction manuals that describe the operations of the different core components as well as how to set-up this marine autopilot.

Bottom-line

The Raymarine T70154 (also called the EV-100 P70R Power Pack) is a fully-enclosed, cockpit-mounted, electro-hydraulic marine autopilot that comes with a 0.5-liter hydraulic pump.

Being well suited to operate hydraulically-powered boats whose design feature a single-outboard setup, this is another worthy addition to our top 5 from Raymarine.

5. Octopus ‘Type S’ Behind The Dash Mechanical Drive Autopilot

 

This is a behind-the-dash mechanical-drive marine autopilot that is compatible with the Morse-290 steering helm.

It comes with a bezel kit that allows it to be fitted into most wheel-steered boats.

This linear drive autopilot is suited to operating a mechanically-steered sailboat as it can directly move the rudder from the rudder quadrant or tiller arm. It features a high-quality cockpit-mounted, fully-enclosed wheel-drive pilot pack.

It is designed for precision monitoring of course direction as well as the yaw, roll, pitch, and heading of the marine vessel so as to detect and immediately correct off-course deviations. This model is manufactured by Canada Metal-Pacific Limited.

This model uses a patented and proprietary autopilot intelligence that allows it to autonomously steer the boat through a pre-routed course without user adjustments.

This compactly-designed easy-to-install model weighs about 12.3pounds. It is 15inches long, 6inches wide, and 8inches high. It is shipped in a partially-assembled state with the wheel unit featuring most of the core components.

This straight-shaft drive unit is designed to be used in small and medium-sized sailing boats. It is designed as a substitute for the manual tilt drive, and its mounting behind the dash still allows the steering wheel angle to be adjusted.

Its front is designed to be used with Teleflex-SH91800, which the user must acquire separately.

It is shipped alongside a 90-degree and 20-degree bezel mounting kit. It also comes with an adjustable friction brake, steering-cable adapter kits, and spacer kits.

This autopilot comes with a reversing pump that uses a proprietary piston-pump technology that allows the pump to have only 3 moving parts, and this also allows for easy servicing.

This pump is powered by either a 12-volt or 24-volt power supply. Another advantage of this pump is that it allows this model to function as a seamless linear drive.

This low-power consumption unit is designed to allow the user to configure its operation. This also allows the user to customize the settings of this autopilot to fit the operations of the marine vessel.

Its control head features a push-button operation controller that allows the user to perform helm corrections when setting a new course for the vessel. It also comes with a long levered handle.

It also comes with several instruction manuals that describe the operations of the different core components as well as how to set-up this marine autopilot.

Bottom-line

The Octopus-Type S is a straight-shaft drive unit that is designed to be mounted behind-the-dash. This mechanical-drive marine autopilot is compatible with Morse-290 steering helm and can autonomously operate a mechanically-steered sailboat.

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Marine Autopilot Buyer’s Guide

What is a marine autopilot system?

The marine autopilot is a specialized set of marine electronics that self-steer a sailboat or powerboat while ensuring that the vessel follows a pre-set (or predetermined) compass course.

Marine electronics are specialized electronic devices designed to be used in marine environments where drops of saltwater – that would have otherwise destroyed standard electronics – are tolerated.

If the marine autopilot is connected to a system of GPS (Global Positioning System) receivers along with a set of boat instruments, then the autopilot can perform complex and advanced navigational tasks.

The benefits of using a marine autopilot

Generally, an autopilot can hold a marine vessel within a pre-set steady course in both light and moderate conditions with the helm movements being kept at a minimum.

Unlike human pilots who get tired and have a limited attention span, marine autopilots will keep on operating, allowing you to take care of other onboard duties.

Likewise, a marine autopilot that has been well-interfaced with GPS can steer accurately and therefore save fuel as it maintains a straighter course that allows the boat crew to reach their destination faster as compared to boats steered without an autopilot.

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The main components of the system

The marine autopilot has 3 basic components; the heading sensor (basically a fluxgate compass), the course computer (the brain or central processing unit of the autopilot), and the drive unit.

The drive unit is basically a hydraulic or motor-powered pump that forces the rudder of the boat to move. Complex autopilots are further connected to a number of additional sensors that serve as data sources that provide navigational data to the autopilot.

These additional sensors include the rate gyro, rudder reference, masthead wind vane, speedometer, and GPS receiver.

How does a marine autopilot work?

So how does a marine autopilot work? To begin with, one must first steer the vessel before engaging the autopilot.

Therefore, the human pilot steers the vessel towards the desired heading and then holds this (desired) course for a minute or so, which allows the course computer to lock the desired course into its memory; and then the AUTO button can be pressed before one releases the helm.

Once the autopilot takes over, the course computer sends signals to the drive unit which respond with helm corrections that ensure that the boat stays within the desired course.

The technology involved

High-quality autopilots use unique features including software algorithms, integration with GPS, auto sea-state, and auto-trim to ensure the vessel accurately follows the pre-set course.

The software algorithms generally use the rate gyro to track momentary pitch and yaw movements as well as to detect off-course deviations, in addition to learning the boat handling characteristics of the human pilot so as to improve its steering acumen over time.

However, this learning feature also comes with a downside because if the human pilot finds it challenging to maintain a particular course, then the autopilot will also find it hard to maintain that course.

You still need the human touch

It is for this reason that autopilots work well in light and moderate conditions as the human pilot can maintain a steady course in these conditions, but in rough conditions where the human pilot is unable to maintain a steady course, then the autopilot will also be unable to properly steer the vessel.

Therefore, autopilots gradually lose their ability to independently steer vessels without input from the human pilot as the waves build-up due to the winds growing stronger and stronger.

A lifesaver nonetheless

A correctly-sized (well-sized) autopilot can be a life-saver. Normally, it uses up to 10 percent of its power most of the time, especially if one is on a calm lake, but as the waves build it increases its power consumption until the maximum power output is reached, and thereafter, it is overwhelmed and can fail if the human pilot cannot intervene in time, but usually occurs in 1 percent of cruising cases.

Still, as the autopilot increases its power consumption as the water gets rougher, it gives the human pilot enough time to put in place a contingency measure (depending on his or her steering skills) in preparation to taking over the steering from the autopilot, and this eliminates the sudden shocks that ordinary boat riders when the waves suddenly get rough and causes the boat to capsize.

Rare causes of failure

Other chief causes of autopilot failure include saltwater seepage into the course computer and corrosion of the drive motor and power socket by salty water.

Therefore, autopilots fitted on vessels cruising on blue-water (in seas or oceans) or going for long-distance sailing are more likely to encounter operational failures as compared to those fitted in boats cruising on clear-water (man-made lakes or fresh-water lakes) or set for short-distance sailing.

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What to consider when buying a marine autopilot

Before one purchases an autopilot, there is a need to find out the correct size required for your boating rig. To do this, one needs to consider 3 key factors;

• boat design,
• displacement,
• and boat length.

Generally, long and narrowboats, long-keeled sailboats, or those whose forward-sections are V-shaped are directionally stable and easy to steer.

Also, those with balanced spade rudders are easier to steer as compared to those whose keel-hung rudders have a barn-door configuration.

Easy-to-steer boats can be driven using tiller-mounted autopilots, otherwise, the more powerful below-deck autopilot is recommended especially for long-distance sailing.

To know the right size of autopilot needed, one needs to check the recommendations (regarding autopilot size) of the boat manufacturer, and then choose an autopilot whose displacement value is 20 percent higher than the uppermost displacement limit given by the manufacturer.

Likewise, one must check the speed of helm-adjustment that the autopilot has, and this can be determined by prioritizing the helm correction speed (measured in degrees per second) of the autopilot over its hard-over time. Generally, a helm correction speed of 8-15degrees per second is recommended.

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The different types of marine autopilot

There are different types of marine autopilots, and they basically vary from each other depending on their drive mechanisms.

Still, before one checks the drive mechanism, one must determine whether the autopilot required is the above-deck or below-deck model.

Above-deck pilots, also called cockpit-mounted or tiller-mounted autopilot is fit for small boats (with a displacement capacity of 13,200 pounds or less) that do short-distance sailing.

When a boat enters a water body, it displaces a volume of water that is roughly equivalent to its boat-weight, and this displaced water can be weighed so as to find the displacement capacity which approximates the boat-weight.

For large boats with large displacement capacities, a below-deck (also called inboard) autopilot is recommended.

Below-deck autopilots are more durable, reliable, and powerful as well as more expensive than above-deck autopilots.

After determining whether an above-deck or below-deck autopilot is suitable, one then checks the drive mechanism.

What type of drive mechanism does your boat have?

The steering system of the boat determines the drive mechanism that can be used to operate the boat.

Usually, there are 3 types of drive units;

• the linear,
• rotary,
• and hydraulic drives.

Linear drives are mostly used in mechanically-steered sailboats where they directly move the rudder from the rudder quadrant or tiller arm.

Linear drives are normally powered by electric motors, but there exists hydraulic linear drives that are hydraulically-powered.

Rotary drives are mostly used in cable-and-rod or chain-and-cable steering systems. Lastly, hydraulic drives are used in hydraulic steering systems.

Important features to look out for

There are different brands and models of marine autopilots sold today. Still, these autopilots can be rated based on their design quality, core pack build, type of control head, and cost-performance ratio

A core pack is a single unit that contains 3 basic components; the fluxgate compass, course computer, and rate gyro; and some autopilot models feature additional components.

Still, a complete core pack must have the aforementioned 3 basic components which imbue it with an AutoLearn capacity that enable it to learn and maintain a steady course.

Equally important, the amperage draw of the core pack selected must match that of the drive unit; and the core pack must be capable of handling the displacement capacity of the boat.

On the other hand, the control head houses the control interface (usually push buttons) and LCD display in a single cockpit-friendly, waterproof enclosure. This control head is then plugged by cables to the course computer.

Points to consider when operating a marine Auto-pilot system

1. Rate of Turn

The most common turn method used by an auto-pilot system is to control the rate of turn.

Here, depending on the model of the marine auto-pilot, the user can set a value of turn rate between 1-300 degrees.

When in a turning motion, the rudder will move enough to attain the required turn rate without exceeding the value set by the user.

2. Rudder Limits

Rudder limits are another variable that will impact turning control. Here, the rudder limit can be set from a value of 1 degree up to the max rudder angle.

Under this control method, the rudder will not exceed more than the set limit while altering the course.

One important point to note; the vessel’s maneuvering characteristics should be considered when choosing the rudder value.

3. Speed

Marine autopilots work less efficiently at reduced speeds. However, more complex maneuvers are reduced speed should be done manually.

Most systems will allow the users to synchronize with the Speed Log. This will give you data on the ship’s speed throughout the journey.

It is a good idea to consult this in order to recognize any error in the log speed, as this will be reflected in the auto-pilot system.

4. Gyro Compass

The Gyro Compass is a very important component to the autopilot system.

Any error in the gyro heading will have an impact on the course taken by the autopilot.

In instances where the gyro fails outright, the autopilot will not be able to take the correct course.

In case of failure or emergency, the autopilot system should be switched to manual so that the user can take control of both the vessel and the course taken.

5. Off-Course Alarm

In situations where the autopilot has gone off course, there should be an off-course alarm.

Here, the user can manually adjust the degrees in order to get back on course. It is recommended that the user then checks the navigation after this to ensure that errors are not occurring.

6. Weather Conditions

Clearly, rough weather and seas will have a detrimental impact on the performance of the autopilot system. This is due to effect the conditions have on rudder movement.

That being said, some modern systems have built-in weather control options. This mode will attempt to adjust the control of the vessel in line with the problematic conditions.

7. Traffic Density

Marine autopilots should not be used in high-traffic areas. This is because they have problems reacting fast enough to navigate narrow channels and conditions that normally mean a build-up of marine traffic.

In such situations, the person at the helm should be in control of the vessel.