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Simrad autopilot

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I would like to adjust the pilot so it doesn't try and steer a really really straight course, as in with a quartering sea it isn't going ape flicking the wheel back and forth.  In The Olden Days you would have a control called some variant of "gain", or "sea state".  I don't see anything that seems to have this effect.  I must say that the control descriptions are not particularly helpful.


Any ideas appreciated.

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Good fast rate compass helps.
Also is it calibrated, got the “ok”
On the three circles for deviation?

no drift on steady heading?
If you going to use sea state then
Set on auto so can learn.
I agree the manual does not explain it well,
I just play around with it in both modes.
If you’re in Auckland I’ve a spare backup AC42
To test whether it’s the unit.
What is you response setting in these conditions?

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It's the NAC 3, using a AP44 or the NSS9 EVO3.  The compass is a rate compass.  All this sh*t cost a lot of money.


The Autopilot controls (and their descriptors) are:

Turn Rate - Target rate of turn used for heading change

Rudder Gain - Ratio between heading error and rudder command

Counter Rudder (secs) - Counteracts the effect of turn rate and inertia

Autotrim - Corrects for static heading error induced by environmental forces

... and a few more that don't have relevance


Coming back from Barrier yesterday I was fiddling with the Rudder Gain.  Originally it was set to 0.25, this seemed to just add a bit of helm when we were off course.  It didn't keep adding rudder to try and correct it, it just seemed to go "ah F$#k it" and error.  I changed that to 3.0 and that was better, but very very busy.  I dropped it back to 0.5 and it seemed closer to where it should work.


What is annoying is that you just want the fecking thing to work.  Trying to understand the manual/instructions is a challenge in itself.  "Ratio between heading error and rudder command" is all well and good but it doesn't actually tell you how to use it - as in "set to a larger number in heavy seas".  As for the Counter Rudder setting in seconds, who knows what that is going to do.  All in all I'm a bit disappointed with all the "latest and greatest" crap I've bought.  The NSS9 EVO3 can run a FLIR camera, which is really fantastic for some people - except if you want to GoTo a waypoint - you can't, you have to go Find/Waypoint/select/GoTo.  I've used systems 20 years ago that were better.....


Hey and thanks to all for your input!

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Ok. The AP44 and NAC3 is a great pilot. Pity it has a rate compass (RC42??) rather than a precision 9, but it will still work ok. Who supplied this gear, and was it professionally installed and commissioned? Is this a sailboat (Unusual to have simrad NSS in a sailboat, normally B&G)? Setup is a bit different for power and sail. What rudder feedback unit is used (if any)?


Ist, the unit needs a proper dockside setup. You must know what units you have and ensure the correct data sources are selected. If this is wrong you will have poor performance. Then the sea trial setup can be done. If this is all done correctly it is sometimes compass position that causes erratic steering and "hunting" of the course.


The NAC 3 selection provides different menus via the AP44 than the older computers did. Now you have  changed the settings on the system the whole install procedure should be re done. 


These pilots are complex, and once done correctly, the installation settings should not be changed, only the user menus. See page 34 of the AP44 operator manual.


I'm a Simrad (and B&G) tech, sounds to me like you need some help in sorting this. Where are you based? Navico tech support 08004628426 or I can put you in touch with your nearest technical support dealer if you wish?


Alternately the Navico number given above will provide you with the information you need to get this unit set up correctly. I have attached the NAC 2/3 Commissioning manual.

NAC 2 & 3 commissioning-manual.pdf



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except if you want to GoTo a waypoint - you can't, you have to go Find/Waypoint/select/GoTo. I've used systems 20 years ago that were better.....


On the B&G Zeus...


On chart view, when you select a waypoint, (or anything else) a little speech bubble pops up with the name of the thing you selected, the name only sticks around for a couple of seconds and if you touch anywhere else it disappears.


When you touch the speech bubble a screen appears giving you the details of the item you selected.


At the bottom is a "goto" button.


(on my b&g the goto is slightly obscured by a predictwind auto route overlay, but the goto button is still there).


Now if that doesn't work, long press the screen for a couple of seconds and a predictive cursor should appear, drag it over the waypoint you're interested in. Then from the menu in the top right find the Goto option.

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