Autopilot question

[Xplicitlnck]

I was coming home from a long trip last week and had the autopilot on for 75% of the trip. First leg was 30 miles in the ocean Flat and calm . Had the autopilot on. (Raymarine) for the most part it would hold a steady straight coarse but every now and then it would wonder. No more then 30 degrees either way. Sometimes when it would wonder it would hold its new coarse but other times it would come back to what I set it to.
Later on in the same trip I had my final leg. About 17 miles in very choppy water (2 to 3 ft chop on the port bow) worth a 15 knt wind also on the port bow. So I set my autopilot but found myself correcting it every 2 minutes or so. It would wonder about 40 to 50 degrees and very frequently. Eventually I just gave up and grabbed the wheel.
Autopilot details.
Raymarine unit
Ray fluxgate
Ray 100 computer
Rl 80 all integrated.
I installed all the electronics last year but as an upgrade it was a plug and play installation from the old electronics.
No metal near the fluxgate
I swung the unit alot a year ago after installation
I tried setting the response to 1 and 3 but didn't c a difference so I left it at 2.

 

[kap2]

Was the autopilot navigating to a way-point or just set to a compass direction? If it was a compass direction the wind and seas would push you off your course.

 

[Xplicitlnck]

Was the autopilot navigating to a way-point or just set to a compass direction? If it was a compass direction the wind and seas would push you off your course.

Just set to a heading. I understand the wind and seas would knock me off coarse but shouldn't the autopilot compensate and atleast put me back on coarse

 

[sbw1]

Not unless you have a gps waypoint entered. Otherwise the pilot holds the heading you set and the wind and waves take the boat which ever way the winds and waves blow.

 

[Xplicitlnck]

Not unless you have a gps waypoint entered. Otherwise the pilot holds the heading you set and the wind and waves take the boat which ever way the winds and waves blow.

I'll try to explain this a little better I understand what your saying and my previous explanation was pretty bad after reading it again.
If I have a heading set for 90* it will run at 90* for let's say a mile then it will start to wonder to let's say 100* (heading on Pilot still says 90 but you can clearly see in the wake that we turned and compass says 100) then it will hold that for a few minutes then turn back to 90*.

 

[PMC]

The same sort of thing happens when I'm running a short frequency following sea. I will experience an over compensation in auto pilot where I'm zig zagging in a very uncontrollable way. I don't think this is a problem with the electronics, but rather the timing of course correction out of sync with bow steer as I hit the next wave.....if that makes any sense.

In most sea conditions, especially out in the ocean auto pilot tracks quite well, and the only course correction is due to wind. Usually it is a short run across the bay is when I experience the "auto pilot shuffle". When this happens I'll take back control of the rudder

 

[bmac]

Jon, I use my autopilot a lot. I believe your issue is that you've set it for a heading and not a way point. To check, set a waypoint a mile or two out. If the autopilot holds course to the waypoint you've got your answer. Think of it this way; when heading at 90 degrees and the boat gets pushed in either direction (by wind, waves or current) the autopilot will correct back to a heading of 90 degrees from your new point of reference, not your original one. To get off by 30 degrees means the boat must have been getting pushed around ALOT!!!

 

[sbw1]

Not to complicate this too much but newer pilots have adjustable sensitivity on the set up program. Essentially, the adjustments take into consideration your speed such as sail vs. power, cruiser vs trawler, trolling vs. higher speed running. The newer Raymarines claim to adjust for characteristics of an individual hull. That said, my new digital pilot does a nice job do holding a course but is not nearly as steady as the old analog pilot that was almost always within 16 feet of the setting. The new technology is about 33 feet, still pretty good.

 

[HUMPH]

At least yours doesn't take a hard right turn when you enable it! After replacing the pump the heading on the autopilot is much different than my compass. I need to get this adjusted.

 

[Xplicitlnck]

At least yours doesn't take a hard right turn when you enable it! After replacing the pump the heading on the autopilot is much different than my compass. I need to get this adjusted.

Thanks everybody. My "problem" is exactly what everybody is describing. Now all I have to do is figure out how to set the pilot to go to a waypoint on an rl80c. Anybody?
Humph
I had the same issue twice . First time Flux gate went bad. Replaced it and she ran straight after. (And metal object within a couple feet of the fluxgate will also cause hard turns) second time was on a friends boat. He had a coarse set on his plotter and when he would engage the pilot the boat would want to go back to were the route started not to the next waypoint. The route start point was behind us so the boat wanted to make a u turn
Also I'm not sure what u mean by pump but you may want to swing the pilot again. That may fix your heading issue

 

[shinsr]

Jon - if your plotter and auto pilot are integrated, it is easy. Assuming same as mine (Raymarine), enter a route (or just go to a waypoint) in the plotter. Once the plotter is engaged to go to waypoint, press AUTO on the auto pilot. Then press the "TRACK" button on the auto pilot. The pilot will then calculate the heading, and (mine gives ascending beep pattern when ready) notify you to press TRACK again - at that point the autopilot will take over. When it engages, the boat may make a sudden turn to get the boat immediately on course (so make sure that you are not in a very narrow channel or that there are no boats right by you when you engage) - you can reduce the severity of that initial engagement by restarting XTE on the plotter immediately before going on auto pilot. To disengage the pilot, simply press the StandBy button (remember that your steering wheel becomes useless while under auto pilot). If you are in a route in Auto mode, you will need to press track after each waypoint arrival in order for the boat to turn to the next waypoint. Good luck.

 

[peterkvs]

I'd say your fluxgate compass is going bad. If you are showing a heading on the autopilot that is different than you actual heading then the fluxgate is going bad. Typically this is worse in heavier seas. Regardless of the wind and current the boat should always point in the right direction. If you set the AP on 90 degrees the boat will keep a heading of 90 degrees. The winds and currents may make your course different than your heading. You said the response was set to 1-3. I believe the response levels are 1-9 with 5 being the default setting, 1 being the sloppiest and 9 being the tightest. So, you might want to try a tighter response. I run mine at 7 typically. If you set a waypoint, which is easy, then the computer generates a straight line from the position you were at when you pressed go to waypoint (or cursor) to the waypoint or cursor position. Then the autopilot adjusts the boats position so that it is on top of that line that was generated by the autopilot. In this mode the response level relates to the cross track error, or how far left or right of the course line the autopilot will allow the boat to be before it steers back to the line. In this mode, if you go to standby and veer away from the course line and then engage the autopilot you will see that the autopilot steers the boat back to the course line and once back on the course line it then steers along the course line toward the waypoint. In this mode the autopilot ignores the heading info from the fluxgate compass except for display orientation purposes.

Hope this helps.

Pete

 

[Woody]

Thanks everybody. My "problem" is exactly what everybody is describing. Now all I have to do is figure out how to set the pilot to go to a waypoint on an rl80c. Anybody? http://reviewmarine.com/wp-content/uploads/2014/11/RL80C-Users-Guide.pdf
Humph
I had the same issue twice . First time Flux gate went bad. Replaced it and she ran straight after. (And metal object within a couple feet of the fluxgate will also cause hard turns) second time was on a friends boat. He had a coarse set on his plotter and when he would engage the pilot the boat would want to go back to were the route started not to the next waypoint. The route start point was behind us so the boat wanted to make a u turn In the case of your friend I think everything was working correctly. If he directed the autopilot to follow a route that's what it'll do....starting from the first point on the route. The first point is the first target. He should read the manual also.
Also I'm not sure what u mean by pump but you may want to swing the pilot again. That may fix your heading issue

http://reviewmarine.com/wp-content/uploads/2014/11/RL80C-Users-Guide.pdf

 

[HUMPH]

Thanks everybody.
Also I'm not sure what u mean by pump but you may want to swing the pilot again. That may fix your heading issue

The pump I am referring to is the hydraulic pump that turns the rudders when the autopilot tells it to. Mine is in the aft/starboard part of my engine room. Mine was leaking so I replaced it a year ago.

 

[Xplicitlnck]

Awesome info everybody thank you. Now I have an excuse to go for a nice ocean run tomorrow and test it out