Backing up your self-steering - good, better and best solutions

Practical: Steering

Tor Pinney examines the options for backing up a boat's autopilot.

Most cruising sailors agree that an autopilot is essential equipment aboard their boat. These tireless electronic crew members hold a magnetic or, optionally, a wind-relative course hour after hour, day after day. That translates into less fatigue for the watch keepers, greater crew efficiency on deck, and a safer, happier passage overall.

That’s why smart skippers take extra precautions to ensure their vessel will never be without self-steering. At the very least, this means carrying repair parts and components. However, for single-handers and couples planning bluewater passages, self-steering is indispensable; repair parts alone may not be enough. For them and for anyone determined to avoid “the tyranny of the tiller,” additional and more versatile safeguards are called for.

Consider what happens if — or according to Murphy’s law, when — the autopilot stops working offshore and can’t be fixed. If that’s all the self-steering on board, the crew is in for some long, tedious tricks at the helm. For a crew of three or more this is merely a big inconvenience. For a cruising couple or a single-handed ocean voyager it can be a more serious matter. Continuous, shorthanded manual steering creates fatigue, and fatigue begets bad judgment, something no mariner can afford.

To help avoid loss of your boat’s self-steering capability, here are a few solutions.

A good solution

As mentioned, prudent sailors carry a complete set of spare parts for their autopilot. As long as the kit includes every breakable component of the autopilot system, plus tools and manuals, that should be enough for most coastal cruising. However, for longer voyages an entire spare autopilot is in order.

Repairing or replacing a broken autopilot should solve the problem. That is, unless whatever incapacitated the first unit also incapacitates the second one. 

A better solution

What if the boat’s electrical system or battery charging system(s) malfunction, so there’s no power to operate an electric autopilot. More than one passage has been curtailed by engine or alternator problems, or by lightning strike damage to the electrical circuitry. This is just one reason many bluewater cruisers value the versatility a windvane contributes to their self-steering repertoire. While windvanes alone usually won’t steer a boat that’s motoring, they will steer under sail more efficiently than an autopilot simply because they don’t consume electricity. That’s why you so often see the real passage-makers sporting windvanes. It’s practically a fraternal flag.

But what if the boat’s steering system becomes inoperable? It doesn’t happen often, but let’s consider the possibility.

Even better

Some windvanes can function as an independent backup steering system should the vessel’s primary system fail. This could be a lifesaver in rare situations. The Auto-Helm that I have on my boat, for instance, features a completely independent auxiliary rudder permanently bolted onto the boat’s transom, with a trimtab — a narrow rudder’s rudder — mounted on its trailing edge. The airvane steers the trimtab, which steers the rudder, which steers the boat. Simple, strong and efficient, this design bypasses the boat’s steering system entirely. No lines lead into the cockpit. If the boat’s rudder or steering linkage is damaged you can steer with the Auto-Helm’s external rudder instead, either by the wind (via the unit’s airvane), or manually (via lines to the trimtab or the rudder head), or (as we shall see) by autopilot.

A new Hydrovane model also employs an external rudder that steers while the vessel’s main rudder is locked off. This unit features its own tiller, allowing instant emergency hand steering when the vane is disengaged, and the tiller is designed to accept a tiller pilot.

According to the manufacturer, the Hydrovane, without modification, provides “self-steering, emergency steering and a practical autopilot”. These folks clearly recognise the multifunctionality of their product.

Australian company Fleming, whose windvanes were used by Jesse Martin and Jessica Watson on their single-handed solo circumnavigations, advertises models that can be optioned for the connection of an electric autopilot. The Fleming’s auxiliary rudder is driven by a servo paddle, a powerful combination, and the windvane’s rudder can be pivoted out of the water. The unit comes with its own emergency tiller.

The best solution

However, windvanes are not the total solution. The best solution for backing up your boat’s self-steering is a multi-faceted approach involving all of the above items plus one more. Here’s the complete list:

1. The primary autopilot

2. Spare parts, tools and manuals for the primary autopilot, plus

3. A complete spare autopilot (or see #5 below!)

4. A windvane, ideally capable of steering the boat independent of the vessel’s own steering system, and

5. A tiller pilot set up to steer the windvane. Since this option is not so common, let’s consider it in detail.

Tiller pilot to windvane self-steering

It takes some strength to steer a sailboat in a blow. Windvanes get their muscle from the force of the water passing along the unit’s steering paddle, servo-paddle, or trimtab and rudder, depending on the design. It doesn’t take much strength to change the angle of these in-water sections and cause them to steer the boat. Just the movement of the airvane responding to wind shifts is enough to cock a paddle or trimtab.

If a little wind can steer a windvane, imagine how easy it would be for even the smallest tiller pilot. Tiller pilots, linear autopilots designed to steer
a boat by its tiller instead of a wheel, are relatively inexpensive. Carrying a spare is not nearly as daunting as duplicating a large vessel’s internal autopilot. In fact, the price difference could pay for your windvane! Modern tiller pilots can be interfaced and remote-controlled much the same as larger, internal autopilots. For the budget-conscious cruiser, a windvane and two tiller pilots may be all you need to ensure you’ll never be without self-steering. I cruised my last boat, an 11m cutter with tiller steering, 30,000nm with just this combination.

Some windvane manufacturers warn against using the tiller-pilot/windvane setup for extensive motoring because it positions the servo-paddle in very turbulent water from the propeller wash. This can cause excessive stress and wear on the windvane’s mechanisms. When in doubt, ask the manufacturer. A tiller pilot can always be used to direct any windvane under sail when a magnetic course is desired or in airs too light for the airvane to steer effectively, and also as a temporary emergency backup under power should the boat’s primary autopilot fail.

How and where to mount and connect a tiller pilot varies with the layout of your afterdeck, stern rail and windvane mount and the make/model/type of windvane.

Here are a few more installation tips:

• Make it easy to connect and disconnect the tiller pilot

• Mount the tiller pilot with the pushrod midway in its throw, and the windvane in its neutral steering position

• Be sure the tiller pilot’s electrical connection is truly waterproof and properly fused

• The tiller pilot should have adequate RFI protection on boats with SSB or Ham radios.

• Cover the tiller pilot to protect it from rain and spray. A vinyl or Sunbrella sleeve with a clear, flexible plastic window over the controls and readout works well. Plastic cling-wrap is better than nothing in wet conditions.

• Even small tiller pilots develop immense thrust. Be aware that the tiller pilot, the windvane, or both could be damaged if someone resumes manually steering the boat and forgets to disengage the tiller pilot.

• An oarlock is raised on small blocks to compensate for the deck’s camber. A wood cradle supports the tiller pilot.