Narrative:

As we were approaching the zzzzz fix on our way into ZZZ; I (pilot flying) noticed that we had a 'yaw damper failed' cas message; and confirmed that the yd (yaw damper) was off. I tried to reengage it; and it worked. About 15 seconds later we were issued a heading by ATC; and at the same time we had a 'yd hold nose left' cas message. I took the controls and went through the memory item. As I tried to re-trim the rudder; the yd and autopilot simultaneously failed; and cas messages illuminated. This was quickly followed by a rudder trim runaway. My first officer (first officer) called for me to hand him the QRH; which I had to delay a moment while I tried to get the aircraft under control. I used the trim interupt switch; but at that point the rudder trim had already pegged to the right. I asked my first officer to please ask ATC if we could just stay on our heading while we ran a checklist to work out a problem. They said yes and asked if we needed any assistance; which we declined.we ran the QRH; while taking turns actuating the rudder pedals; as the control forces were very tiring. After pulling the rudder trim breaker I slowed down even more; which reduced the aerodynamic loads and helped reduce the control forces. ATC asked if we needed to divert to ZZZ1; which we also declined; and said we needed another minute to finish out checklist and should be good to continue on to ZZZ. At this point my first officer was actuating the rudders; switching back and forth between feet; and we agreed I would take over on landing. When we were ready; I asked my first officer to let ATC know we would need to go slower than usual approach and landing. They said that was fine. We came in to land; with flaps at 40 degrees. My first officer was still actuating the rudders; while I was hand flying. We discussed that I would let him know when I would take the rudders and asked that he be ready to help if needed; as there was a 9 knot direct crosswind from the left. We came in to land; and at the last minute I had to ask him for assistance in helping me keep the plane straight on the runway. We landed without further incident.

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Original NASA ASRS Text

Title: PC12 Captain reported a yaw damper message and runaway rudder trim.

Narrative: As we were approaching the ZZZZZ fix on our way into ZZZ; I (Pilot Flying) noticed that we had a 'YAW DAMPER FAILED' CAS message; and confirmed that the YD (YAW DAMPER) was off. I tried to reengage it; and it worked. About 15 seconds later we were issued a heading by ATC; and at the same time we had a 'YD HOLD NOSE LEFT' CAS message. I took the controls and went through the memory item. As I tried to re-trim the rudder; the YD and autopilot simultaneously failed; and CAS messages illuminated. This was quickly followed by a rudder trim runaway. My First Officer (FO) called for me to hand him the QRH; which I had to delay a moment while I tried to get the aircraft under control. I used the TRIM INTERUPT switch; but at that point the rudder trim had already pegged to the right. I asked my FO to please ask ATC if we could just stay on our heading while we ran a checklist to work out a problem. They said yes and asked if we needed any assistance; which we declined.We ran the QRH; while taking turns actuating the rudder pedals; as the control forces were very tiring. After pulling the rudder trim breaker I slowed down even more; which reduced the aerodynamic loads and helped reduce the control forces. ATC asked if we needed to divert to ZZZ1; which we also declined; and said we needed another minute to finish out checklist and should be good to continue on to ZZZ. At this point my FO was actuating the rudders; switching back and forth between feet; and we agreed I would take over on landing. When we were ready; I asked my FO to let ATC know we would need to go slower than usual approach and landing. They said that was fine. We came in to land; with flaps at 40 degrees. My FO was still actuating the rudders; while I was hand flying. We discussed that I would let him know when I would take the rudders and asked that he be ready to help if needed; as there was a 9 knot direct crosswind from the left. We came in to land; and at the last minute I had to ask him for assistance in helping me keep the plane straight on the runway. We landed without further incident.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.