Narrative:

Loss of directional control during ground roll after landing. This was the ninth landing of the training sortie and the student's second lesson in the tailwheel airplane. The student made a safe wheel landing (soft field technique); in light and variable winds; and we were decelerating when the student began to create minor oscillations with the rudder. I instructed him to not over correct and that he was inducing the oscillation. The student made an over-correction and the aircraft moved out of alignment with the runway. I took the controls to prevent a ground loop and planned to coast into the grass; but the airplane nosed down upon leaving the runway and caused a prop strike. The aircraft stopped quickly since we were at a slow airspeed when the strike occurred; but still managed to nose into the ground on the paved berm of the runway. I believe the ultimate cause was the variable winds. The winds were favoring the north and runway 35; but were variable to the east. Although light; they may have created the minor deflections in airplane alignment that led to the loss of control.

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Original NASA ASRS Text

Title: Flight instructor reports departing the runway and nosing over after taking over from his student who was over controlling after a wheel landing.

Narrative: Loss of directional control during ground roll after landing. This was the ninth landing of the training sortie and the student's second lesson in the tailwheel airplane. The student made a safe wheel landing (soft field technique); in light and variable winds; and we were decelerating when the student began to create minor oscillations with the rudder. I instructed him to not over correct and that he was inducing the oscillation. The student made an over-correction and the aircraft moved out of alignment with the runway. I took the controls to prevent a ground loop and planned to coast into the grass; but the airplane nosed down upon leaving the runway and caused a prop strike. The aircraft stopped quickly since we were at a slow airspeed when the strike occurred; but still managed to nose into the ground on the paved berm of the runway. I believe the ultimate cause was the variable winds. The winds were favoring the north and Runway 35; but were variable to the east. Although light; they may have created the minor deflections in airplane alignment that led to the loss of control.

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.