How does autopilot on a sailboat work

This article is focused on my research on the boat brands owned by Brunswick…. There tends to be a lot of confusion over the different types of fire extinguishers that are out there for your protection.

Many people think that the red traditional ones are the only models out there and that these models are all the same. However, in reality that is not necessarily true. Whether it be serious conversations or just casual ones, and you might be wondering what it means. Or why you seem to be the only one…. When looking into uses for radios, marine and CB radios are often mentioned together.

These two radios share similarities in the fact that they are both radios and that they can be used for somewhat similar purposes. Overall, however, marine and CB radios are very different. Depending on what kind of boat you have and how heavy it is, the speed you can expect at various horsepower varies dramatically. A boat that weighs pounds can go twice as fast on the same hp as a boat that weighs lb. You may be amazed by how affordable quality sailboats can be, but initial costs are not your only consideration.

Are Sailboats Expensive To Maintain? Skip to content. How do Autopilots Work? Autopilot Data Sources Autopilots steer your boat based on the information that they receive from other sources. Here are some of the ways that your autopilot can find out how to steer your boat well: Wind vane.

The wind vane typically sits on the top of your mast and can constantly tell your autopilot where the wind is coming from, which can be very helpful when using an autopilot in variable wind conditions. Rudder sensor. Knowing where your rudder is in the water can tell your autopilot whether it needs to apply more pressure or not.

Rate gyro. This can be very helpful information to let your autopilot know when it may need to make lots of minute adjustments Speedometer. GPS receiver. So how does the autopilot system work exactly? There are two options in the sailing community when people hear about autopilots. There is the self steer, which is technically not an autopilot system but rather provides a self steering boat as the name suggests whereas the autopilot system provides a fully automated experience.

You may also like: The best autopilot for small boats. Here are the two main:. Some will swear by the self steer and others like the fully automated. There are benefits to both and an argument can be made to have both options if you have the budget. Essentially, a self steering system helps steer the boat. The diagram and video below helps illustrate this. However, with a self steering system, it is not as conventional as a fully electronic autopilot system. Also, the windier it gets, the better it works, unlike a fully automated electronic system.

Finally, one last benefit is it can act as an emergency rudder. However, those with older systems that output only NMEA data are at a disadvantage as the wiring is significantly more convoluted and the protocol will only support a relatively small number of devices.

Given the reliance on the pilot, power management on a sail boat is an important consideration for any passage of more than around hours. This can be particularly true for lower specification units that struggle to keep the boat on course, thereby using more power than a system that will steer a better line. For long offshore voyages back-up charging options are also important to consider. For some crews this will be little more than an inconvenience, however, for weaker, less experienced or short handed sailors it has the potential to create significant problems, especially on long passages.

Installing a second unit that can be engaged at the flick of a switch therefore makes a lot of sense. However, even that is by no means a fail-safe panacea if it relies on the same instrument data stream and charging system as the main unit. There are legions of boats with a second pilot drive that has sat festering in a damp locker for months, or even years, and no longer has any chance of functioning. For boats travelling very long distances with a small crew a wind pilot is therefore still a popular option that provides a completely independent back up that will work even in the event of total power failure.

No pilot will work efficiently on a sailing boat if the sail plan is not well balanced. Paying careful attention to sail trim, including shortening sail in good time as the wind increases, is crucial to the ease of steering the boat and the performance of all types of self-steering systems.

Many electric pilots allow you to tweak a range of settings to enable the unit to maintain an efficient course across a wide range of conditions. The bottom line? There was a time at which any long-distance voyaging boat would sport a windvane self steering gear on the transom.

They tend to be robust, often requiring servicing only after tens of thousands of miles, require no electrical input, and can often be easily fixed using locally sourced parts and labour even in remote parts of the world. These remain undeniable advantages in today's world, and many seasoned skippers swear by their wind vane gear for good reason. On the downside, the upfront cost can be relatively expensive, and windvanes tend not to be effective sailing downwind in light airs, when the apparent wind is low, and are useless for motoring in a calm when the apparent wind is always from ahead, irrespective of your course.

For this reason many yachts with a windvane system will also carry an electric pilot, although the latter does not need to be of a high specification as it will only be used in easy conditions.

After first being developed in the post-war years by the likes of Bernard Moitessier, Blondie Haslar and others, windvane design now favours servo pendulum types, which magnify the power produced by the small vane on top of the unit. A number of companies have with their own designs based on this theme, most of which work on similar principles but offer various advantages in terms of size, price or track record.

One that stands out from the rest is the Hydrovane, which has a number of devotees thanks to the auxiliary rudder it incorporates. Equally, the WindPilot series is seen as well engineered precision systems that have many knowledgeable and enthusiastic followers. How do autopilots work on a boat? Basic autopilot units Key inputs Autopilot drive units The right size unit Autopilot control unit Power management Redundancy Getting the best from a pilot Wind vane systems.

The essential elements of the Garmin GHP 12 autopilot. Powerboats need responsive pilots downwind as well since they tend to slew and yaw as they run down seas. Slow pilots get out of synch with the waves, and oversteer as a result. The best way to measure the speed of an autopilot is the number of degrees per second of helm correction, not hardover time, which may include more or less throw for different models. Shaman, my vintage Cal 40 sailboat, yaws strongly in following seas.

They are easy to install and have adequate performance for most conditions. Below deck pilots like the 0. Wheel-steered sailboats over 38' will use a more powerful below-deck linear drive pilot, which is protected from the elements and much more durable.

Installation on any below-decks pilot is more expensive. The autopilot automatically re-engages when you hold a steady course. Choosing a below-deck pilot for either a powerboat or a sailboat is a three step process, involving 1 selecting a drive unit, 2 selecting a corepack and 3 selecting a control head. Select the right hydraulic drive unit based on the capacity in cubic inches of your hydraulic steering ram since the drive unit is a supplemental pump that actually moves your ram.