Narrative:

I finished flying the mission near the jackson airport and continued towards the airport. While descending to the airport I checked the weather and received a clearance into the airspace and traffic pattern. The weather was 170 15g25 clear below 12;000 feet. I continued to the traffic pattern altitude and was cleared for a left downwind for runway 20. It was quite choppy around the airport during my base to final turn as I descended further. On short final around 100 feet it became significantly smoother and I continued to land. I was configured to land with full flaps doing approximately 70 indicated on touchdown. I paused; then applied the brakes while closing the throttle. We rolled for 1-2 seconds then I felt a yawing motion to the right. It felt like my right main had locked up so I released the brakes to regain traction and used the rudder to maintain centerline. I asked my [passenger] if my right tire was flat or destroyed and he said no. I regained control of the aircraft; then I immediately felt a second yawing motion to the left followed by a wild spinning motion to the left. The plane rotated like a top 30-40 degrees towards the left while also pushing us towards the edge of the runway. I attempted to maintain centerline but felt too much force and thought I would roll it. I continued towards the grass trying to slow the aircraft and maintain directional control. I maneuvered the aircraft away from airport lighting into the grass and before entering the grass applied some pitch up to prevent flipping the aircraft. I kept the propeller away from the grass and kept pressure off of the nose wheel. Once we came to a complete stop I looked to my [passenger] to see if he was ok. The tower radioed to us if we needed assistance and I said no. We taxied back to the ramp under the aircraft's power and parked it at the ramp. We were able to safely shut down the aircraft and secure it on the ramp. After the aircraft was shut down I inspected to see if there was any damage and found that the bolt holding the right wheel pan was missing and the wheel pan was loose.

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Original NASA ASRS Text

Title: C206 pilot reported losing directional control during the landing roll for unknown reasons.

Narrative: I finished flying the mission near the Jackson airport and continued towards the airport. While descending to the airport I checked the weather and received a clearance into the airspace and traffic pattern. The weather was 170 15G25 clear below 12;000 feet. I continued to the traffic pattern altitude and was cleared for a left downwind for Runway 20. It was quite choppy around the airport during my base to final turn as I descended further. On short final around 100 feet it became significantly smoother and I continued to land. I was configured to land with full flaps doing approximately 70 indicated on touchdown. I paused; then applied the brakes while closing the throttle. We rolled for 1-2 seconds then I felt a yawing motion to the right. It felt like my right main had locked up so I released the brakes to regain traction and used the rudder to maintain centerline. I asked my [passenger] if my right tire was flat or destroyed and he said no. I regained control of the aircraft; then I immediately felt a second yawing motion to the left followed by a wild spinning motion to the left. The plane rotated like a top 30-40 degrees towards the left while also pushing us towards the edge of the runway. I attempted to maintain centerline but felt too much force and thought I would roll it. I continued towards the grass trying to slow the aircraft and maintain directional control. I maneuvered the aircraft away from airport lighting into the grass and before entering the grass applied some pitch up to prevent flipping the aircraft. I kept the propeller away from the grass and kept pressure off of the nose wheel. Once we came to a complete stop I looked to my [passenger] to see if he was ok. The Tower radioed to us if we needed assistance and I said no. We taxied back to the ramp under the aircraft's power and parked it at the ramp. We were able to safely shut down the aircraft and secure it on the ramp. After the aircraft was shut down I inspected to see if there was any damage and found that the bolt holding the right wheel pan was missing and the wheel pan was loose.

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.