Take a look at almost any cruising power or sailboat these days and you’re likely to find some form of self-steering gear installed. In our modern age of boating, having the desire to keep your vessel on course without the need for a crewmember to constantly be at the helm is almost a given. But the path to getting the right setup for your boat can be a vexing problem.
When we talk about self-steering, the category runs from electric or hydraulic autopilots all the way to sheet-to-tiller steering and several types of windvanes. The issue, however, is that there are numerous choices on the market to sift through. Following are some basics to help you choose and refine the best system for you, your boat, and crew.
Electric, hydraulic, and mechanical self-steering units are all essentially achieving the same function – steering your boat in a desired direction with a limited need for human intervention. Electric and hydraulic “autopilots” are steering to a course that has been set on a control unit. They also can steer to a series of waypoints that you have programmed into a connected multifunction display or chartplotter. Conversely, windvane steering systems aren’t steering to an exact course, they’re set to steer to the direction of the wind relative to your boat and where you are trying to go. Let’s look at both.
Electric and Hydraulic Autopilots
All basic autopilot units for wheel-driven boats come with three central components: a heading sensor (fluxgate compass), a central processing unit (computer that acts as the “brain” of the system), and a drive unit (electric motor or hydraulic pump that applies force to the rudder). These drive units are installed below deck and connect to the boat’s steering system, but there are a few above-deck options too.
Modern autopilots have come a long way in a short time. Brands like Raymarine, B&G, Lowrance and Garmin all have variations of the same setup. They include methods of maintaining a more accurate course than their predecessors, such as auto-trim, auto sea-state and integration with GPS. The latest developments include SmartSteer software algorithms from Raymarine that use a rate gyro to more accurately detect off-course deviations and an algorithm that learns your boat’s handling characteristics to improve steering over time.
If you want to go higher end with more features, there are pilots on the market from companies like NKE that add data sources including a masthead anemometer for wind, a rudder reference that tells the pilot’s processor where your rudder is pointed, a rate gyro that keeps track of momentary yaw and pitch movements and a GPS receiver or a speedometer. Overall, your boat’s type of steering and how it connects to the autopilot’s drive mechanism are what will differ when you’re choosing an autopilot.
When you get to this step in the purchasing process, it’s a good idea to consult with a professional who has experience installing various types of autopilots. You don’t want to end up with something that doesn’t suit your boat’s steering system because it will be prone to poor performance and could fail when you need it most.
For tiller-driven boats, your options are more limited when looking for an electric autopilot. The most common method is to buy an above-deck cockpit tiller pilot that has an electric arm to move the tiller to keep the boat on course. Simrad’s TP22 and TP32 TillerPilot and Raymarine’s ST1000 Plus Tiller Pilot and Evolution EV-100 Tiller Sail Autopilot are the most common options and fit a wide variety of tiller-steered sailboats up to about 40 feet. Historically, the problem with these tiller pilots comes when they are pressed into hard duty like crossing oceans, where the demands on them are great and are required for longer periods of time. This is where you might want to consider adding a windvane. Often, a skipper will fit a tiller or wheel pilot as a backup to a windvane when he or she decides that a vane is most suitable for the vessel.
Windvanes
Steering a sailboat with a windvane is a magical experience of balancing the boat’s sails and using the wind to keep it on course. Instead of simply pushing a button to stay on a specific heading, you’re setting a vane mounted on the boat’s transom to the apparent wind direction. When the top of the vane is standing up straight, you’re sailing your desired course. When the vane falls to one side or the other, the windvane’s steering mechanism takes over and turns the boat back to the intended course. Not only are windvanes ingenious in their design and use, they use no power, meaning you can sail for miles without it drawing down your batteries.
Sailors have long tried to devise ways to keep a boat sailing on course with limited input from a person stationed at the helm. Tiller sheeting, or “sheet-to-tiller” steering, works by using one of the boat’s sheets and a bungee cord connected to the tiller to essentially work against each other to keep a boat tracking relatively straight. This works well on some boats, but certainly not for all.
In the 1950s, former Royal Marine Herbert “Blondie” Hasler began developing vane gears for sailboats, and he remained a leader in this field for decades afterwards. He gained practical experience by completing four singlehanded Atlantic crossings in his junk-rigged Folkboat, Jester, which was considered radical at the time. With every crossing, it’s believed that Hasler was setting new records for sailboats shorter than 35 feet. The crossings culminated in a passage of 33 ½ days from Newport, R.I., to the Solent in July 1964. During the 12,000-mile trip, Jester was steered by hand for fewer than 50.
The now well-known trim-tab system was the first to be perfected incorporating a differential linkage to eliminate the over-steering tendency of earlier gears. In the first single-handed Transatlantic Race in 1960, Jester was fitted with a prototype trim-tab gear and advanced experiments were carried out, mainly with windvanes of different sizes.
The next milestone in the history of vane gears was Hasler’s invention of the Pendulum Servo system in 1961. For the first time, it let sailboats with counter sterns be steered effectively in a variety of conditions without needing complicated modifications to the rudder and rudder stock.
Fast forward to modern windvanes and there are many options on the market, but three major types stand out: trim tab, servo-pendulum and auxiliary rudder (direct drive). What all three have in common is that they employ a vertical vane that is oriented to align with the desired apparent wind angle to keep the boat on course. Beyond that, we start to see the differences, which is where you’ll want to focus when deciding on which windvane is best for your boat.
While trim tab windvanes started the genre, they are the least common today. The main reason is that they require modification to the boat’s rudder in the form of attaching an actual “trim tab” to the foil’s trailing edge. The trim tab is then moved by the vane, which swings it one way or another to steer the boat. A major flaw to this design, though, was that trim tabs could not be used with boats with counter sterns. This is where the servo-pendulum came to fruition.
The introduction of the servo-pendulum windvane was a massive jump in self-steering. Considered the “classic” windvane, servo-pendulums have a small servo blade (which is not a rudder) that goes into the water and a larger windvane that needs clean air to help steer. When the upper vane is set to the wind direction, the blade turns in the water and swings to one side or the other depending on what course correction is needed. The resulting force is powerful and is transferred to turn the main rudder through control lines that are attached to the tiller or steering wheel. There are several servo-pendulum models currently on the market, including those by Monitor, Aries, CapHorn, Hebridean, Windpilot, Neptune and more.
A common critique of the servo-pendulum is that its moving parts are in constant motion and the control lines can chafe during extended periods of use. This, of course, depends on the boat, installation and how you are using the gear. As with any piece of equipment, it is important to understand the differences between servo-pendulum windvane brands and how they vary between models, which is beyond the scope of this article.
Due to some of the deficiencies with servo-pendulum windvanes, in came the auxiliary rudder windvane system. Unlike the servo-pendulum, the auxiliary rudder windvane uses its own dedicated rudder and not the boat’s main rudder to primarily steer the boat.
The upper vane gets set into the wind and the main rudder is locked in a position to account for any weather helm. The vane’s gear is then engaged and the boat is being steered by the auxiliary rudder. As the boat falls off course, the apparent wind angle changes and drives the vane over. The movement of the vane is linked to a turning gear and the unit’s rudder down below moves to properly adjust the boat’s heading.
An advantage of the auxiliary rudder system is that, in the event that your main rudder is disabled, the vane’s rudder acts as an emergency backup or spare. The primary manufacturer of auxiliary rudder windvane systems is Hydrovane.
No matter the windvane system you choose, one of the biggest obstacles before using it is figuring out where and how it is mounted on the boat’s transom. The manufacturer should have a detailed set of guidelines for mounting because the connection to the boat needs to be strong to account for the associated forces that it will endure throughout its lifetime. Also, assistance may be needed with figuring out any modifications to your boat that may be necessary to most efficiently run the vane. Another consideration when comparing models is making sure that the upper vane remains in clean air. Things like solar arches, davits and Biminis can all affect air flow getting to the vane, which may diminish its performance.
What’s right for you?
With all the options laid out, the most difficult part of the equation comes back to what you think is the right choice for your boat. Certainly, questions abound. First, when thinking about adding or upgrading your self-steering system, you must look forward to what your aspirations are with the boat you have. Are you setting off on a blue-water voyage around the world? Are you mostly day sailing in your local waters with occasional overnights? Or are you coastal cruising, making hops no longer than a couple of days and nights?
If you’re daysailing and mostly staying local, it might make the most sense to install an electric autopilot first. Then, if you decide to tackle coastal or offshore hops, adding a windvane could be a good choice. If you’re heading offshore, redundancy is the key, which is why many ocean-going sailors choose a combination of electric or hydraulic autopilot coupled with a windvane. As one experienced sailor I talked to said, “If you can have both, that’s an ideal setup. Why not?”
Throughout my years of cruising, I’ve come to like the setup that we have on our Grand Soleil 39, Yahtzee. We have an electric autopilot coupled with an auxiliary rudder windvane system. The autopilot mostly gets used for shorter hops and the windvane is pressed into service for longer passages. There even have been times when we use both, which can help when making sail changes or while sailing in heavy wind and seas.
I also know that what’s right for us isn’t ideal for everyone. Good luck with your search. I hope to see you out here. n