Self-Steering Systems

Autopilot or Wind Vane?

The good news is that for yachts below c 34 ft there is a good range of very capable electronic autopilots available, their reliability has improved significantly over the years and prices are not excessive. The bad news is that for yachts below c 30ft there are few wind vane systems available at a sensible price and some are in short supply coming from “cottage industry” suppliers, one of whom only works on them in the winter when not working as a rigger.

Whilst on Internet forums hard core wind vane enthusiasts claim a wind vane system is suitable for single handed sailing in all circumstances, that argument does not really stand up. 

A wind vane system:

  • Will generally not auto-tack so you must handle the tiller, the mainsail and the jib sheets, try that in a confined situation in a blow, on a spring tide with the IOW fast ferry bearing down on you from one direction and a racing fleet from another. You can do it, but it is not to be recommended.
  • Needs a reasonable amount of wind over the deck to work which is not always there.
  • Does not work when motoring.
  • Can’t be switched on almost instantly, although with experience it can be done quite quickly in a steady wind. So not much use coming in or out of the marina or anchorage when you want the self-steering for a few minutes at a time.
  • Will not normally turn a boat through more than a few degrees quickly. With an autopilot, press the 10 degrees button the appropriate number of times or press the auto tack / gybe button and look after the sheets.
  • Are expensive and overhang the stern so avaricious marina berth masters will charge you more if you can’t or don’t remove them.

I think that is enough. The auto pilot certainly has disadvantages some of which are explored below, but in my opinion the first self-steering system to get is an autopilot of some sort, linked to wind instruments if possible.

For inshore and costal work that’s all you need. How far you are prepared to go offshore without some backup is down to:

  • Risk tolerance.
  • How long you are prepared to steer if you run out of volts or suffer a failure.
  • The ability of the boat to self-steer for short periods with or without some jury rigged system.
  • How far you can get in that time under power or sail and 
  • Where that would get you at any point on a particular voyage.

With a full tank and reserves I have diesel for at least 66 hours steaming at 5.5 knots and normally have fuel for a minimum of 30 hours, so in reasonable conditions I can sail, motor sail or sail at 5.5 knots for as long as I can stay awake, if we assume that is 10 - 15 hours if I have not slept much, means a trip to the south of Ireland,  is not unreasonable and cross channel no problem at all. In a 24 foot boat with an outboard the risk increases or the acceptable range decreases.


For Jester class yachts up to about 3 tonnes (or 5 tonnes for the more expensive) a tiller pilot from Raymarine, Simrad etc., is a good option, at the time of writing these range in price from about £350 to £550, but £450 is probably a realistic minimum as from that price point you can interface them to wind instruments or a dedicated vane and can therefore sail to the apparent wind direction as well as to a compass bearing.

The Raymarine Tiller Pilot controller, the
autopilot is linked to the wind instruments
and is holding the boat to an apparent wind
angle of 54 degrees.
More functional and hopefully more reliable systems have multiple units. The Raymarine EV-100 Tiller autopilot, which I have on Sancerre, is currently about £1.3K, this has key electronics components below deck including the computer and the 9 axis sensor, and above deck is the control / display unit and a ram unit to move the tiller. 

This system will interface to the plotter and wind instruments (steering to true or apparent wind) and will provide the ships head bearing to the plotter, radar (for stabilisation), etc. It will also display the boats heading on the control unit. 

The Evo is advertised as suitable for boats up to 6 tonnes but that is probably a bit generous unless the boat is quite well mannered. More expensive variants and systems are available for wheel steering and heavier boats.

Most of the advantages of autopilots are implied above, from my experience with the EVO there are a few disadvantages:
  • If the boat does not respond fairly quickly to a full helm command the unit gives up. The helm will remain at full, but you need to intervene and that can be a problem if you are sleeping. A wind vane will keep trying – although it may not succeed.
  • If the wind instruments go down – my radio linked ones did, first occasionally then permanently – and you are using the wind vane input, it gives up.
  • In heavy weather, especially with a quartering sea, power consumption can be an issue over long periods.
  • They make an annoying noise in difficult conditions.
  • A spare ram for a hybrid system is expensive, over £600 last time I checked, so I don’t carry one, if I did not have the wind vane system and was going a long way I would probably take a tiller pilot as back up being cheaper and covering the entire system.
Autopilot Tip

Tiller pilots are usually held in place by gravity and would fall out in a knock down and somehow, they can come out of the socket when not in use, so attach a safety line, annoyingly mine does not have a loop for one.

Wind Vane Systems

Sancerre's SeaFeather.
Apart from the issues mentioned above the biggest problem with wind vane systems is the cost. Most are designed for larger boats and are expensive. The well regarded “Wind Pilot” range has a “light” version starting at €2.5k + shipping from Germany but the maximum boat size is quoted as only 2,500 Kg, so OK for some but not man enough for a 30 footer when a “Pacific” model will be required and is likely to cost over €3.5K.

I understand that an Aries system is a lot more expensive (they are coy about costs) and a Hydrovane is certainly a lot more, in fact more than the purchase price of a reasonable 24 ft yacht! 

On a more realistic level my SeaFeather cost just under £2K new and has been used with success on a fairly heavy 35 foot Yamaha on a very windy OSTAR and an AZAB. It was on several boats on the 2019 Jester Baltimore and is the most common one I see on boats up to c 30ft. 

The Hibernian is the best budget option I have found and can be built from a kit for between £550 and c £950 for a luxury version. 

Or you may be lucky and find a good second-hand system that would suit. 

I have made a couple of minor modifications putting a 2 part block and tackle with jammer into the tiller lines so that the tension can be adjusted and I have put shackles at the other end of the lines so that the unit can be removed from the boat without messing about with knots.  And since the picture was taken, I have put a stainless anti rubbing strip on the top of the tiller so that the chain can be left lying over the tiller when the SeaFeather is not in use without causing damage.
A spare wind vane is a sensible spare, mainly in case the "live" one is droped when removing or putting it back onto the unit (when in harbour etc. it is best to remove it to stop it being bashed about by the wind) on serious voyages a spare servo blade would be sensible “just in case”, in use it is protected by the skeg but a pot rope or flotsam could catch it. 

The most likely way of damaging it is in the marina (I have that T shirt) or deploying / retrieving The Jordan Series Drogue. If hit heavily it should kick up, damaging the locking mechanism, if that happens a peg can be inserted to hold the blade down.

The SeaFeather doing its thing heading north from the Holy Island of Lindisfarne, 2021. The wind has perked up a bit and the boat has a bit more weather helm than would be ideal.

Wind Vane Tips

All will  require some practice to get going and it may not be intuitive, I find the best approach is to get the boat on course and in balance using the autopilot then adjust the SeaFeather vane until the servo blade is consistently vertical and then do a quick change from the autopilot to the wind vane.

Some boats may need to carry a little less sail to avoid steering problems, particularly griping in gusts. Sancerre is fine with plenty of sail upwind but on a reach in strong winds some discretion is sometimes required.

Potential Self Steering Problems when Reaching

Wind vane systems and autopilots steering to the apparent wind can steer a very erratic course whilst reaching in a wind of variable strength, heavy boats with relatively small fore and aft sails are unlikely to be significantly affected but lightweight boats with large fore and aft sails and any boat carrying large downwind sails can easily end up steering 30 degrees or more from that intended. 

The problem is that, particularly in light winds, a relatively small increase in wind speed will a cause significant increase in boat speed, the apparent wind will therefore swing forward, and the boat will bear off and the speed will likely increase further. This is likely to be most significant when the wind is between 90 and 150 degrees off the bow, on a wider reach the effect probably reduces to be insignificant at c 170 degrees.

With a wind vane system, not much can be done except perhaps to set the system to steer above the course intended in the low wind speed and hope that it will average out. The same approach could be used with an autopilot coupled to the wind instruments but, if the system allows, a better approach will often to be to change the system to follow the true wind and to adjust the sheeting etc to cover the range, this will result in an over sheeted sail in light winds but a more stable course. But be warned if the wind increases significantly the boat may become over-pressed.

When using an autopilot on a compass bearing a similar approach can be followed but there will be no protection from a wind that varies in direction as well as strength so the skipper will have to stay awake and alert.

If already on a fairly broad reach consider bearing off to a very broad reach, the increasing speed will have less impact on apparent wind and at least you will be going in a relatively straight line.

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