AutoPilot

[Roger_Peterson]

Should the Auto Pilot servos be always on or should they be switched.

 

[preid]

You will get a red "ERR" for each servo on the top of the screen if there is no power to the servo(s). Mine are "on" but not active until I activate them via the three ways mentioned in the Pilot guide.

 

[mmarien]

I put in a switch for the AP servos. The red X's are a good indication of the state. I usually turn them off for takeoff and landing.

 

[dynonsupport]

The design intent for the AP servos is that they come on with the master and stay on throughout the flight. They are designed to survive engine cranking and other spikes at startup and shutdown. As mentioned above, if they are off when you have your EFIS on, you'll get errors, but this isn't a problem.

We do recommend that they have a pilot accessable switch or circuit breaker so that in a whole cascade of failures, you could turn them off if needed. The servos require constant communication with the EFIS to stay engaged, so they will disengage immediately if the EFIS ever fails, or if a whole host of other things occurs. We've never heard of a servo engaging itself or failing to disengage when it should, and even if it did, the design of a stepper servo means you can override it and fly the airplane.

As a company, Dynon doesn't see an advantage to a user turning them on and off independent of the master switch. Worrying about them after takeoff or before landing just seems like extra workload for no real advantage. Most standalone autopilots require you to turn them on before takeoff because they calibrate on the ground and they can't be cycled in flight, and nobody worries about the AP having power when taking off or landing. No good reason that the Dynon servos should be treated differently. But if this gives you more confidence to power cycle them manually at different phases of flight, the system supports this.

 

[Roger_Peterson]

Thanks for the help. First time around so trying to limit my screw ups. Will still have plenty.

 

[TRCsmith]

With regards to the powered on servos (autopilot off): do you feel the servos through the stick?
I understand that you may feel clicking or clutch drag through the control stick. Is that so? If it does will that go away if the power to the servos is removed? :-?

As reported from another Long EZ driver with SV.

Thanks

 

[dabear]

I can feel the servos on the stick (not yoke) when on the ground and doing a "free & correct" check prior to take off. However, once there is load on the controls (airspeed) I can't feel them. Regardless of the servos being powered or not.

 

[dynonsupport]

When the servos are powered on but not engaged (autopilot off), there is NO DIFFERENCE in drag than when you have no power going to the servos at all (breaker/switch pulled). The motor is literally in the same powered off state. Note that there isn't any clutch that separates the motor from the controls at all, so there's no difference there either. The only thing that is getting power when the servos are getting power but the AP isn't engaged is the electronics in the servo.

 

[TRCsmith]

Thanks for the response. My friend has that problem, so I think I'll take a look at it and see what gives.