Cruising sailors tend to under-utilise autopilots, usually simply turning them on and walking away. Learning how to trim and set up your pilot to suit the conditions will not only get you to your destination faster, but should reduce battery consumption and make for a smoother ride.

In this article I aim to highlight a few ways to get the most from your pilot. I will talk you through three popular systems to see how easy it is to change the settings and how much human intervention is required to get the best performance.

 

Pilots tested:

SmartPilot X-5 by Raymarine

with ST6002 controller

This pilot is five years old and represents a generation of pilots that is perhaps most prevalent on cruising boats today. The model has now been superseded by the Evolution range. I’m very familiar with the X-5 as I have two of these autopilots installed in my 21ft Mini Transat boat and they have supported my single-handed sailing over thousands of miles.

 

B&G AC12N

course computer controlled by Triton head

We tried this pilot on the Elan 410 Esprit, which is owned by Neil Vardy and used for charter work, racing round the cans and extended passagemaking. This is the newest of all three pilots tested and offers a more intelligent computer that automatically changes settings to suit conditions.

 

NKE Gyropilot 2

The NKE has long been the autopilot of choice for single-handed sailors. The system is aimed heavily at racing sailors and it is expected that they will adjust settings to optimise performance.

I trialled this system on Concise 8, a third-generation, Mark Mills-designed Class 40, with British skipper Ned Collier Wakefield.

 

Modes:

Compass is the default mode for most autopilots; once activated, it will steer the compass course shown on the control head at the time of pressing the button.

Choose compass mode for a quick fix while you go forward or below, when motoring, sailing in a confined area, performing sail changes or if fetching or reaching in a challenging sea where the apparent wind angle may change frequently.

 

Wind or windvane – Engaging this mode allows your course computer to ‘see’ the wind and steer to it in the same way as a human helmsman. With the exception of conditions mentioned above, I will always choose to steer in wind mode, especially downwind at speed.

For best results switch between true or apparent wind angles as conditions change. Use a true wind angle when sailing downwind; it will allow the boat to surf down waves, accelerating as the apparent wind angle moves forward, but staying on track. Switch to apparent wind mode when sailing upwind to allow the pilot to ‘follow the telltales’ just as we would.

Changing between true and apparent wind modes is not always straightforward. If you have extended periods when you do not use your pilot, try keeping a check card in the chart table so you do not have to open the manual every time you want to change.

On the X-5 it needs to be done in the user calibration menu, which takes quite a few button pushes. It cannot be done while the pilot is engaged, which can mean steering and pushing buttons at the same time.

The Triton has intelligent sail steering, which offers three options for wind mode, automatic, true or apparent. The automatic mode is the default option and will select true or apparent according to your wind angle and switch between them as the boat heads up or bears away. This feature particularly impressed me as we sailed Esprit under spinnaker and I watched the pilot transition seamlessly from using a true wind angle when running to apparent when reaching, much as a real helmsman would.

The NKE is perhaps the most straightforward to operate, as true wind mode and apparent wind mode are entirely separate options. You can switch between modes while the pilot is running and whichever mode is in operation when standby is pressed will be remembered. However, if you are considering an NKE pilot, be aware that the true wind mode does not come as standard; you have to buy a code to unlock this on your course computer.

 

Rudder angle/NFU is featured on both the B&G and NKE pilots and simply holds the rudder at one angle much as a wheel lock would. Though this has limited use under normal conditions, we used it on Esprit in light airs and flat water to hold the boat on a steady reaching course with well-trimmed sails. In light airs and large swell this could save your batteries and even your sanity by avoiding continual course adjustments while waiting for the breeze to fill in.

 

Navigation mode will allow the pilot to link with chart plotters or GPS and drive to waypoints or follow routes. This full integration of navigation and autopilot comes from the world of ships and could potentially take all the hassle out of navigating as routes can be designed on your sofa at home and then uploaded before a passage. On a boat I sailed early this year, installed with a Garmin plotter and pilot, the plotter asked ‘Shall I engage the pilot?’ when a ‘go to’ waypoint had been selected.

Although this level of integration between steering and navigating brings a degree of sophistication on board, I have never used this mode with my autopilot other than when motoring in a familiar area and in benign conditions.

I would express a word of caution if considering using this level of automation as it could take away your engagement with navigation and the world outside. An error made plotting a waypoint the night before could be followed without question.

 

Settings:

Response

Response could be interpreted as the number of corrections per minute the pilot makes to stay on course.

Sometimes called the ‘sensitivity’, the response settings are normally the easiest to adjust. In super-light breeze I may knock the response right down to reduce power consumption and keep the boat from making jerky movements. The friskier conditions become, the more I need my pilot to work, especially under spinnaker, so the response will go up in line with how actively I would be steering if on the helm.

It is always a good idea to have a go at steering yourself before turning the response level up as if the boat is struggling to keep on course it is often an indication that sails need to be trimmed or reefed.

The B&G pilot has an automatic response feature, which will select either high response or low response parameters depending on boat speed. This feature should make life easy; however, when we tested the pilot in light winds and flat water, the auto response settings seemed to make the helm unnecessarily active.

It is possible to select response levels manually in the pilot settings menu, though if you press standby the pilot will return to the default automatic response setting.

The gain function on the NKE Gyropilot combines both rudder response and rudder gain as detailed below. Pick a lower number for slower speeds and calmer waters and increase to the highest value for the most challenging conditions.

 

Wind trim

The wind trim determines the sensitivity of the pilot when operating in wind mode. This is an often-overlooked control, but if you are struggling to keep your course to the wind, it will often be a tweak to the wind trim that is required and not the response.

For both the B&G and Raymarine pilots, the wind trim will be set to a default value somewhere in the middle of the range, but to gain optimum performance from your pilot it is worth changing the wind trim value to suit the conditions.

A high wind trim value will lead to a boat that responds to every shift and gust, which could be beneficial when sailing upwind in flat water or when under spinnaker downwind. But when reaching in a heavy sea a high wind trim value can lead to a rough and erratic ride. It is definitely worth recording wind trim values against conditions when your pilot is set up well.

The NKE uses a wind damping feature; this is particularly useful for boats with large rigs, which would feel significant acceleration at the masthead owing to the action of waves. In heavy seas you can increase the wind damping to update the course computer with information fewer times per minute so smoothing out any accelerations caused by waves. In smooth seas a lower damping value will allow more frequent and sensitive course corrections.

 

Rudder gain/