Narrative:

My instructor and I were doing a training [flight] for my instructor rating. After completing stalls [and] slow flight; we continued with steep turns. During the turn to the right; the ailerons kept snapping to the left. We immediately discontinued practice and set a course to [airport]. My instructor took over flying and I backed him up with the checklist. He verified the autopilot was in the off position. We then squawked 7700 and declared an emergency. We continued the flight only using rudder and elevator. We did not use flaps [because of] concern there was something wrong with the wing. We landed uneventfully. We could have tried pulling the fuse for the autopilot. During the preflight; I failed to look inside the wing at the cable. Also; I just came from work; [and was] without sleep in 24 hrs.

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Original NASA ASRS Text

Title: A C182 student pilot reported abnormal aileron response during a training flight. They declared an emergency and returned to base using only rudder and elevator control.

Narrative: My instructor and I were doing a training [flight] for my Instructor rating. After completing stalls [and] slow flight; we continued with steep turns. During the turn to the right; the ailerons kept snapping to the left. We immediately discontinued practice and set a course to [airport]. My instructor took over flying and I backed him up with the checklist. He verified the autopilot was in the off position. We then squawked 7700 and declared an emergency. We continued the flight only using rudder and elevator. We did not use flaps [because of] concern there was something wrong with the wing. We landed uneventfully. We could have tried pulling the fuse for the autopilot. During the preflight; I failed to look inside the wing at the cable. Also; I just came from work; [and was] without sleep in 24 hrs.

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.