Narrative:

I was training a student pilot in an american champion 7ECA. We were taking off on runway 28 with a left crosswind. Full power was added and the stick brought forward with left aileron for the crosswind correction. As the tail came up student over corrected with right rudder and tried to steer with right aileron. This caused aircraft to head towards right side of runway. I firmly said 'my controls' and tried to correct with proper aileron and rudder inputs. The student resisted and I yelled 'my controls.' student then relented on controls and I attempted to get aircraft back on the runway but was unable. I then brought power to idle and stick full back elevator with left aileron. The aircraft rolled through the grass across a north/south runway and came to a stop in the grass. We then taxied back onto 28 with tower's permission. Nothing appeared to be wrong with the aircraft so I requested taxi to parking. At the hangar a thorough debriefing was conducted with the student regarding: crosswind correction; positive exchange of controls; and aborted takeoffs. A mechanic looked the aircraft over and found no damage. The incident was caused by improper crosswind correction and my inability to take corrective action because of my student's grasp on the controls. This could have possibly been avoided by a more thorough briefing emphasizing the meaning of 'my controls.'

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Original NASA ASRS Text

Title: When the student pilot failed to relinquish the controls to the instructor pilot during an aborted crosswind takeoff attempt; their Aeronca 7ECA exited the runway; crossed another and was finally brought to a stop with no damage or injuries to either airman.

Narrative: I was training a student pilot in an American Champion 7ECA. We were taking off on Runway 28 with a left crosswind. Full power was added and the stick brought forward with left aileron for the crosswind correction. As the tail came up student over corrected with right rudder and tried to steer with right aileron. This caused aircraft to head towards right side of runway. I firmly said 'My controls' and tried to correct with proper aileron and rudder inputs. The student resisted and I yelled 'MY CONTROLS.' Student then relented on controls and I attempted to get aircraft back on the runway but was unable. I then brought power to idle and stick full back elevator with left aileron. The aircraft rolled through the grass across a north/south runway and came to a stop in the grass. We then taxied back onto 28 with Tower's permission. Nothing appeared to be wrong with the aircraft so I requested taxi to parking. At the hangar a thorough debriefing was conducted with the student regarding: crosswind correction; positive exchange of controls; and aborted takeoffs. A mechanic looked the aircraft over and found no damage. The incident was caused by improper crosswind correction and my inability to take corrective action because of my student's grasp on the controls. This could have possibly been avoided by a more thorough briefing emphasizing the meaning of 'my controls.'

Data retrieved from NASA's ASRS site as of April 2012 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.