Hi all.With say, an engine failure, the yaw damper has a significant input. If I then add some manual rudder input, the yaw damper input is removed. Example: yaw damper commands large right rudder deflection. I add a little left rudder. Rudder then snaps from hard right over to the left to match my rudder input. Is this correct behavior?

Are you using the fail-active system? That is definitely not normal for fail-passive.

This has nothing to do with the autoland system. He's talking about the yaw damper system which is completely separate.

The yaw damper travel is limited to 2° left and right if flaps are up, 3° L and R with flups not up. Its movement is summed mechanically to the pilot inputs.So, in case of engine out, the maximum deflection will be 3 degrees plus or minus to the pilot input.

The yaw damper travel is limited to 2° left and right if flaps are up, 3° L and R with flups not up. Its movement is summed mechanically to the pilot inputs.So, in case of engine out, the maximum deflection will be 3 degrees plus or minus to the pilot input.

I assumed out would be summed too, but that's not what was happening for me. Would someone else try this to see what happens?

Bump

Your manual input overrides the YD...Try dead foot - dead engine

I will try in the sim, but the real one will not override the command, the command is summed to the YD command.YD is limited to 3° maximum wich is insuficient for engine out.I will also check if stby yaw damper is functional...I'll report soon

Hm, I see similar behavior here. Slight rudder displacement during an engine out condition will center the YD indication immediately, and rudder (as seen in spot view) will snap to rudder position. Release of rudder pedals will make YD oscillate quite a bit, and then restore its original deflection. Certainly no summing up happening for me.

Hm, I see similar behavior here. Slight rudder displacement during an engine out condition will center the YD indication immediately, and rudder (as seen in spot view) will snap to rudder position. Release of rudder pedals will make YD oscillate quite a bit, and then restore its original deflection. Certainly no summing up happening for me.

Many thanks for verifying. Pity it won't be fixed in SP 1. Hopefully someone from PMDG will spot this.

I tried, YD deflection seems to be fine for me, rudder movement is reasonable inside the 2/3 degrees.When manually input, the rudder moves as the joy move, while manual moving I've not seen YD movement, when stopping moving YD tries to correct and restore the pilot input after damping all unwanted yaw accelerations. I've not seen summation, but can be a limit of FSX, for me is not a real issue, seems to work for me, if not for you, maybe I've not understood what you mean, maybe a video can help.

but can be a limit of FSX

That one I doubt. As they use their fly-by-software system, they could do virtually anything to the flight controls, regardless of hardware control input. In fact I'm sure this is what they do all the time anyways, think of CMD/CWS. So I would think they could also take their calculated YD deflection and add any eventual hardware input on top of that.

I tried, YD deflection seems to be fine for me, rudder movement is reasonable inside the 2/3 degrees.When manually input, the rudder moves as the joy move, while manual moving I've not seen YD movement, when stopping moving YD tries to correct and restore the pilot input after damping all unwanted yaw accelerations. I've not seen summation, but can be a limit of FSX, for me is not a real issue, seems to work for me, if not for you, maybe I've not understood what you mean, maybe a video can help.

If the yaw damper is say, deflecting 2/3 degrees to the right, manually add a little left rudder - the rudder will snap from right to left. It shouldn't do that.

If the yaw damper is say, deflecting 2/3 degrees to the right, manually add a little left rudder - the rudder will snap from right to left. It shouldn't do that.

Exactly confirmed. That's what I see. The snapping is always most noticable on the opposite side of current YD deflection. Adding rudder IN direction of YD deflection doesn't do that, or at least way less.

Exactly confirmed. That's what I see. The snapping is always most noticable on the opposite side of current YD deflection. Adding rudder IN direction of YD deflection doesn't do that, or at least way less.

Yep, a real pain trying a cross wind landing with an engine out. Not sure anyone from PMDG has made a note of this. Will raise a support ticket next week if no one else does (only got primitive web access through my phone at the mo.)