Pip Hare runs through the best way to set up your autopilot including adjusting the modes and best practise
I view my autopilot in the same way I view sail plan and weight distribution – a variable that must be adjusted and monitored constantly. Human beings change our steering style to suit conditions and so we must trim the autopilot in the same way. This helps not only with good course keeping and speed, but also helps optimise energy consumption.
Most autopilots are capable of several different modes of operation and the key to getting best performance is to know which mode to use when.
Compass mode
This is normally the default mode when a pilot is activated. The unit will be following a compass course. Use this mode for making passages under motor, reaching or fetching under white sails and for all sail changes.
I also favour compass mode in shifty conditions or difficult sea states when sailing upwind. If using compass mode in these conditions it would be necessary to set a softer trim on your sails to allow for variations in the wind angle.
Use twist to do this, bring the jib cars back, loosen the vang and bring the traveller up track, this will allow for a wider course variation without losing power from the sails.
Wind mode
Wind mode will steer the boat to a given wind angle. I’d choose to use wind mode when sailing upwind VMG (beating), when sailing with the wind aft of the beam or reaching with a soft sail (spinnaker or Code 0).
There will normally be an option to steer to a True Wind Angle (TWA) or an Apparent Wind Angle (AWA). As a rule of thumb choose to steer to TWA when the wind angle is 70° True or above and use AWA for anything less than that.
Using AWA upwind and TWA downwind allows the pilot to make the correct gust responses; heading up in the gusts when steering to windward while avoiding gybing downwind.
More modern pilots now tend to have an ‘auto’ wind mode which will select either AWA or TWA for you; the machine will normally switch over at 91° True. This is not a bad setting to leave the pilot in as default, but in gusty conditions if close reaching with a powerful sail, such as a Code 0, it may be more advantageous to switch to true wind mode at a higher angle. It’s worth having a dive through the settings to learn how this can be achieved.
Sail trim when using wind mode in flat waters can be fairly powerful; upwind harden your leeches using more mainsheet and set jib cars forward. Downwind use plenty of vang on the mainsail and set symmetrical spinnakers with the pole back.
In bigger waves use a softer sail trim to allow for variations in course and heel angles, soften leeches using twist and ease the spinnaker pole forwards.
Regardless of conditions I’ll always switch to compass mode for sail changes, reefing in and out. During these times the boat will be expected to change speed and balance significantly and this can make the course erratic if steering to a wind angle. So, before a sail change I switch to compass – often increasing the response time by two levels – and then switch back to wind mode once the change has been completed.
GPS or waypoint mode
In this mode your autopilot will take you to a specific waypoint using a GPS course or even follow a route. This is not a mode I normally choose to use but it could be useful for crossing an area with a strong cross-tide as using COG (course over ground) to steer the boat will automatically compensate for any tidal drift.
This mode is only suitable for shorter legs, or long legs in calm conditions, as on any longer offshore passages you’ll make better progress by navigating to the weather and tidal conditions rather than directly to a waypoint. If your autopilot is capable of following a route it will normally prompt you to accept the course change for each new leg.
Rudder reference
Also known as No Follow Up (NFU) mode, most pilots have this it simply locks the rudder into one position – so the pilot is not following a course. Use this for dock checks (if your boat is moored then it’s difficult to check whether the pilot is working due to being unable to change headings and respond) by moving the rudder from side to side using the +10/-10 commands.
Rudder reference mode can also be used as emergency steering, if your pilot ram is connected directly to the quadrant and your steering cables break then you can use the pilot to move the rudder for close quarters manoeuvring as an alternative to an emergency tiller. It can also be used to lock the helm in position when hove too or lying a hull.
Tacking and gybing
If your pilot is able to sail in wind mode then it will generally have some advanced functionality around tacking and gybing which is worth investigating, particularly if you sail short-handed.
The tacking function will take your boat through a tack and can usually be set up to swing through a specific number of degrees or onto a reciprocal wind angle. I’d normally set the pilot to steer through a set number of degrees as, unless you’re very sure your wind instruments are exactly calibrated to centre (which can take quite a lot of work), tacking through a set angle will normally safeguard against coming out of the tack too high and losing steerage.
You may also have the option to trim ‘rate of turn’ through the tack. This will be a setting to change according to sea conditions, wind strengths and the make-up of your crew. For light winds or challenging sea states use a faster rate of turn, slow the tack down in strong winds with flat water.
If using a self-tacking jib the tacks can be fast in almost all conditions. In challenging sea states think about easing the mainsheet prior to the tack to ensure the boat does not end up head to wind if it takes a while to wind the jib on.
Gybing is not so straightforward. Some pilots will use the tack function to gybe so the same options can be chosen, but if using this make sure you have properly adjusted the settings before each gybe to avoid surprises or sudden course changes. The NKE HR pilot I used on the Vendée Globe allowed me to program a pause in the centre of the gybe, which is an incredible feature for a solo sailor on a big boat, so it would steer the boat downwind, pause while I pulled the sails around then head up onto course afterwards.
I often manage gybing manually by putting the pilot into compass mode and then steering through the gybe using the +/-10 buttons on my remote control at a speed that is right for me. This method works for gybing but would not work for tacking as speed is too slow.
Set up and networking
To access all that your pilot can do it must be networked to the rest of your instruments. If you have a mix-match of instruments or have added the pilot in at a later date then don’t overlook this functionality.
Providing the pilot with access to GPS data will provide a level of redundancy for failures of the log or compass – often allowing GPS course and speed to be used instead. Linking wind data to the pilot will allow you to access the wind mode which will provide much more comfortable and accurate course keeping.
Invest in a remote control
With many people increasingly favouring multifunction displays to combine instruments, chartplotters and pilot, I am seeing quite a few boats now where there is only one display in the cockpit and so the pilot controls are not always close to the helm. This is often the case with twin wheeled boats.
With any autopilot set-up consider that a lone sailor should be able to turn the pilot off and take the helm from one position: this is a safety consideration as well as a practical one. You may never aim to have one person alone in the cockpit but it could happen.
Investing in a good remote control for your pilot is a good way to solve this problem without the need to buy more displays or make holes in your boat. The remote will be able to adjust the course from anywhere on board the boat, as well as engaging and disengaging the pilot.
I’d recommend mounting the remote on an elasticated arm strap which is worn on the outside of foul weather gear and handed over at the change of each watch. I favour this over a necklace arrangement as I have, on a couple of occasions, leant against a remote control that was tucked down the front of my foulie jacket, and turned the pilot off by mistake.
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