Narrative:

During initial tailwheel instruction in stinson 108; we were on our third and final landing of the day. My instructor instructed me to land the aircraft. On the rollout the tail began to swerve; so the instructor said; 'my airplane' and took the controls. I immediately said; 'your airplane' and gave control to the instructor. He initially corrected and started to slow the airplane; but then there was a hard swerve to the right; the tail came around and the plane traveled towards the runway edge. The right landing gear left the runway; and as the instructor turned the plane back onto the asphalt; I heard the prop strike and said 'I think we had a prop strike'; he replied 'yes; I think so.' he later said his foot had slipped off the rudder pedal; causing the hard swerve to the right. He got the plane stopped and we taxied back to the hangar. The engine sounded fine; and we confirmed upon shutdown that the propeller edges had been bent. The only damage to the plane appears to be the prop strike. The instructor later said he thought the problem was very avoidable and that he felt responsible due to the foot slip. I believe the problem was caused primarily by instructor's unfamiliarity with the aircraft; as he said the rudder pedals are in a different place in his airplane; so that when he corrected with the rudder his foot slipped. He also remarked how the rudder handled differently than in his aircraft. Also; I am not signed off in the plane which is why I was getting the instruction. Continued training; and/or sticking with tricycle gear aircraft can prevent a recurrence of this event.

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Original NASA ASRS Text

Title: Stinson 108 student pilot reports swerving during his third landing and having the instructor take control. The instructor initially corrects then ground loops the aircraft causing a runway excursion and propeller damage.

Narrative: During initial tailwheel instruction in Stinson 108; we were on our third and final landing of the day. My instructor instructed me to land the aircraft. On the rollout the tail began to swerve; so the instructor said; 'my airplane' and took the controls. I immediately said; 'your airplane' and gave control to the instructor. He initially corrected and started to slow the airplane; but then there was a hard swerve to the right; the tail came around and the plane traveled towards the runway edge. The right landing gear left the runway; and as the instructor turned the plane back onto the asphalt; I heard the prop strike and said 'I think we had a prop strike'; he replied 'yes; I think so.' he later said his foot had slipped off the rudder pedal; causing the hard swerve to the right. He got the plane stopped and we taxied back to the hangar. The engine sounded fine; and we confirmed upon shutdown that the propeller edges had been bent. The only damage to the plane appears to be the prop strike. The instructor later said he thought the problem was very avoidable and that he felt responsible due to the foot slip. I believe the problem was caused primarily by instructor's unfamiliarity with the aircraft; as he said the rudder pedals are in a different place in his airplane; so that when he corrected with the rudder his foot slipped. He also remarked how the rudder handled differently than in his aircraft. Also; I am not signed off in the plane which is why I was getting the instruction. Continued training; and/or sticking with tricycle gear aircraft can prevent a recurrence of this event.

Data retrieved from NASA's ASRS site as of July 2013 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.