AH-6000, veering off course

[Dave Brengelmann]

The AH 6000 on our new boat just delivered a couple of months ago will not stay on course when sea conditions are moderate. It's fine when it's flat calm, until we hit a large wake, but after hitting a large wake or swells in heavier weather, the 6000 will send us on major course changes. As I run to hit the stand by button, typically the course will change as much as 40 degrees.I have recalibrated the AH a couple of times, but this does not seem to make any difference.What's the next step (aside from reading the manual) :0)

 

[Bill Boudreau]

Tech Support

The autopilot systems are highly dependant on the installion and the original specifcation. I would suggest calling Raymarine Technical Support at 800 539 5539 . Please have the vessel displacement, steering system information, model of ST6000 autopilot (Type 100 or 300 course computer and Type of drive) and calibration information. They will also want the number you got for "deviation" during the compass linearization and the other equipment you have onboard.

 

[Don Alexander]

Sensitivity too High??

Dave,Sounds to me as if you may have the rudder sensitivity set too high. If so I believe this can lead to a wildly divergent oscillation in the course holding. This can often occur in servo systems and be proved mathematicallyThis is not a defect in the pilot it is just that, after a small deflection, the pilot applies too much corrective rudder, the boat takes a second or two to respond, and, by the time the pilot realises this, the boat has turned too far. The pilot then applies even more rudder in the opposite direction. The sequence repeats over and over again with the corrections getting wilder every time. Usually it gets worse the faster you go so make an initial adjustment at slow speed and then do it again at higher speeds until it is stable when you are flat out.In calm water you can see this over compensation in the boats wake.Regards,