Autopilot Issue

[Autigr]

This has happened three times now, once last summer and twice this summer during a 2600 mile cruise up to Juneau and back. 2019 R-27 OB. I’m running along at 7-8 mph. I’ve been using the autopilot and I disengage it for one reason or another. When I re-engage, it immediately throws the helm hard over to the stops and the boat veers into a tight circle. Not sure but perhaps to port each time (I can’t remember for sure). Repeated attempts to re-engage it results in the same behavior, both in heading hold and route-following modes. The fix: shut everything down and turn off house and engine batteries. On re-start it works fine. All Garmin software up to date as of June of this year. Anyone else experience this? Any ideas how to fix it?

 

[ShaneM]

It sounds like the autopilot is trying to put you back on course at the last position in the track. Because you are still moving forward when you disengage, you've moved forward relative to the track so it's trying to turn you around and get back the last position.

Before re-engaging, you need to re-calculate the track. I don't have the chartplotter in front of me but I think it's along the lines of Menu -> Additional -> Re-calculate Path, then re-engage the autopilot.

 

[4th Draft 2]

We have a 2025 R29 with Garmin autopilot. We have used it a lot this year with no problem. EXCEPT, i find if i use the wheel with a hard turn to engage Shadow Drive to avoid objects (lobster buoys mostly) after 4-5 times it will do what you describe. I have found a couple of sources that suggest it could be engaging the Shadow drive causes an air bubble or something in the hydraulic line. I’m still trying to understand it. But, so far it seems that if i use it once or twice in an hour or two there is no problem, but if i use it more, it goes into the tight circle. If i have the problem, and leave autopilot off for 30 minutes or so, it works fine again.
I do not find any direction from Garmin to use it only in emergency, or that it is ok to use routinely.

 

[Submariner]

I have my chartplotter set up for a split screen. 1/3 and 2/3 split. The 1/3 side is 1nm or less, and the 2/3 side is 1nm or more.
The 1/3 side is my danger zone. If a boat is on that side of my screen, I pay more attention to it.

For autopilot... when I have to deviate off course to avoid a log, or another boat, I disengage autopilot and maneuver around. Once I'm past the obstacle I will set heading hold on an intercept course with my course based on the 1/3 split side of my screen (since it's zoomed in to 1/2 a mile, 1/4 mile... etc...) When I get close to my original course, I will then engage "follow route". If I see a lot of yellow on the autopilot display, I immediately hit the standby button and go back to heading hold to wait longer and allow the boat to get closer to the original course. Once I hit "follow route" and I have very little yellow (the yellow is indicating off-course), the boat will naturally align back with it and continue on our course.

The problem with autopilot getting back on course is more difficult at slow speeds (7 knots or less). Just takes more time. But the process is the same as described above. If I just hit follow-route and I'm really off course, LaZina and I call that a "Crazy Ivan" from the movie Hunt for Red October as the boat will make as sharp turn that we don't want.

I don't leverage the shadow drive feature much. At least, not on purpose. Channel Surfing is driven by autopilot about 95% of the time and playing the "heading hold to get back on course" game is just a part of my driving.

Garmin's suggestion to this is to simply click the "re-calculate" route, which will re-adjust your course, based on your current position. I never do that because most auto-guidance routes I put in I have to make minor adjustments to the course. For example, auto guidance will run me right by the Mukilteo ferry terminal, with about 1/4 mile clearance... What if there's a ferry there, leaving, arriving or close to arriving? I want at least 1-2nm clearance coming around the ferry docks. So I'm always adjusting the auto-guidance course for things such as this. To hit that re-calcuate button would remove all my adjustments.

 

[Autigr]

I follow what you're saying. That's how I normally re-join the magenta line as well. Or just manually steer until I'm within 10' of it and aligned in pretty much the right heading. But when it went nuts it would throw the helm hard over regardless of whether I was engaging it in heading hold or route following. Same reaction. And it wouldn't roll out on a new heading either - just continue with the helm at the stop until the autopilot disengages with some diagnostic about excessive hydraulic pressure or something like that. I was usually trying to get control of the boat back and not paying full attention to the msg. One day when it went berserk I tried to re-engage it 3 or 4 times in different modes over the course of about 2 hours just to learn more about the failure mode. I never got it to re-engage correctly until I shut everything down and turned off the batteries. Then it worked fine... It sound like at least some others have experienced the same issues. I may try and give Garmin a call and see what they can tell me. One lesson learned for sure: make SURE you're in clear water before trying to engage this thing!

 

[Submariner]

@Autigr, when the boat does a "Crazy Ivan" when engaging the autopilot, it's usually associated with a speed source error, (boat isn't going fast enough), the hydraulics will lock up as the autopilot put the engine hard over, and still needs more rudder... (the boat isn't turning fast enough). Then I'll hear the hydraulic relief valves and the steering wheel is locked up. To get out of it, I will engage the autopilot for a second to heading hold, then back to standby while turning the steering wheel. The hydraulics will unlock themselves as the pressure vents and return steering to operational. I've never had to power it all down as you've illustrated.

It's, by far, easier to cause a "Crazy Ivan" at slow boat speeds (under 7 knots).

When engaging the auto-pilot, my finger is near the red "standby" button on the autopilot... if the autopilot display shows a lot of yellow once engaged (meaning, I am really off course, by a lot), I immediately press standby to prevent a "Crazy Ivan".

 

[Pandion]

This has happened three times now, once last summer and twice this summer during a 2600 mile cruise up to Juneau and back. 2019 R-27 OB. I’m running along at 7-8 mph. I’ve been using the autopilot and I disengage it for one reason or another. When I re-engage, it immediately throws the helm hard over to the stops and the boat veers into a tight circle. Not sure but perhaps to port each time (I can’t remember for sure). Repeated attempts to re-engage it results in the same behavior, both in heading hold and route-following modes. The fix: shut everything down and turn off house and engine batteries. On re-start it works fine. All Garmin software up to date as of June of this year. Anyone else experience this? Any ideas how to fix it?

Do you know if your autopilot has Direction Control enabled? Direction Control will allow the autopilot to steer the boat going backwards.

Our boat came with Direction Control enabled (it might be enabled by default) and we experienced similar behavior when it would accidentally get activated while using the GHC20 autopilot control unit. In standby mode, if your right soft key has "Direction" above it, the Direction Control feature is enabled. There is a small round icon in the upper right corner of the GHC20 screen. If you see an arrow pointing down inside that icon, Direction Control is active and your boat is attempting to follow a course while moving backwards. You can disable this feature in the settings.

 

[GZigmont]

We had the same issue on our R-29 CB a few years ago. It only happened on one particular route I programmed in. I deleted the route and reprogrammed a new one and it solved the problem.