Autopilot for Dummies

[Lexam]

Ok give it to, me. What exactly can an autopilot do and can't do. Does it just sail your boat in a straight line? Or can you feed it information like weather and it will steer around it. How smart is your autopilot?

[David M]

At its most basic, all it does is steer a heading. It's usefulness is to make it so someone does not have to be at the helm all the time. Autopilots can be integrated with a chart plotter or a computer with navigation software in order to follow a trackline. You could theoretically have it steer around a storm if you lay in a trackline with the proper waypoints. It will not do this automatically though.

Autopilots are basically dumb devices that can only hold a heading or steer along a trackline. I am actually glad they are not advanced enough to make any intelligent decisions...far too may people would start relying on them to make important decisions for them.

Also, you can't walk away from an autopilot for any length of time, they can and do fail periodically. It is also foolish and technically illegal not to keep a proper lookout.

[Unicorn Dreams]

David has it covered.
If it did too much, you wouldn't get anywhere unless it could trim sails.

[cal40john]

They can usually steer to a wind angle from wind instrument data as well.

[Paul Elliott]

Some autopilots with steer-to-wind capability can tack or gybe the boat when you press a couple of buttons (it will just turn the rudder, not trim the sails). This can make singlehanding a bit easier.

[markpierce]

Autopilots aren't hired captains.

I use mine all the time except in "close circumstances." Frees me up to do "lookout."

[Lexam]

Thanks guys, I've tried looking up the basics and couldn't find a good explanation. And I see on some where it says it has "utilizes a self-learning and adaptive software algorithm, providing the ultimate in course keeping capability." I'm thinking to myself what is self learning exactly in this context? What's there for the auto-pilot to learn if you are pointing it in straight lines?

[DeepFrz]

They "learn" (adapt) to sea state (wave height, etc) and the steering characteristics of the boat. Maybe other things. Many of the autopilot manufacturers have good descriptions of their capabilities. Google should get you there.

[bazzer]

AutoLearn does indeed adapt the autopilot characteristics to the boat it's installed on, were are talking raymarine here, it also will take "drift" into account when steering to a waypoint so the heading and the COG might well differ quite a bit, it does on my boat. It also figures out how much weather or lee helm it needs to hold the boat steady etc etc It also will tack the helm for you as well as allow you to "dodge" a obstacle and return to your original track when needed. All very useful IMHO

[Inkwell]

I use the AP to steer into the wind, so I can raise the main. I use it while motoring long distance. It does not hold a course under sail very well. The AP is a little too small for my 16000 lbs boat to hold a course under sail. But it is handy for the above purposes.

[Greg4cocokai]

We use our A/P 24/7 when underway. 90% of the time it is set to a wind angle to keep the sails trimmed. If the wind shifts more than 15 dagrees an alarm goes off and we correct accordingly. Has worked great for us for 5 yrs and 24,000 nms. Not so important sailing off the wind. Cheers, Greg

[s/v Jedi]

More advanced pilots can do so much more than steer a compass heading...

-> steer a wind angle, tack/gybe or even anti-gybe
-> follow a depth contour line
-> auto-steer patterns incl. SAR patterns
-> control bow thruster for very low speed steering

Another example: if you want to steer a straight line over ground, most pilots require you to set a GPS waypoint and let the pilot steer to that. Some pilots however allow you to point the bow to some feature like a harbor entrance and then command the pilot to steer to there in a straight line over ground. It will correct for wind drift, cross currents etc. (very nice feature!)

ciao!
Nick.

[boatman61]

Most AP's are only as smart as their owners...
Mines really dumb... it just steers a course...

[redcobra]

Originally Posted by Paul Elliott

Some autopilots with steer-to-wind capability can tack or gybe the boat when you press a couple of buttons (it will just turn the rudder, not trim the sails). This can make singlehanding a bit easier.

I use mine to tack when single handing if it's over 15 knots of wind.

[Lexam]

Getting a whole tutorial here, thanks!