Narrative:

During a multi engine training flight; I simulated an engine failure on the takeoff roll by retarding the right mixture to idle/cutoff after the student had applied takeoff power (as I had been trained to do in my mei training). The student failed to recover properly from the simulation and would not release the controls after I instructed him to do so. I quickly retarded the left mixture to idle/cutoff; but the aircraft was already exiting the runway onto the grass; destroying a runway light. I had given the student ground instruction on multi-engine aerodynamics; and we had discussed what to do in the event of engine failures; both on the ground and in flight. The student was using a checklist and had read aloud the proper procedures for recovering from an engine failure during the takeoff roll; and we had discussed it prior to the starting the engines and again prior to taking the runway. I learned that simulating an engine failure on the takeoff roll during the first flight is not the safest way to conduct flight training and that I should be more alert for students to improperly correct for adverse situations in order to conduct safer flight training. The airplane was mildly damaged; only propeller blades that needed replaced or filed down and re-balanced; and the aircraft was operational again within several days.

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Original NASA ASRS Text

Title: PA-44-180 instructor reported the aircraft departed the runway; causing minor damage; when power was cut to simulate an engine failure.

Narrative: During a multi engine training flight; I simulated an engine failure on the takeoff roll by retarding the right mixture to Idle/Cutoff after the student had applied takeoff power (as I had been trained to do in my MEI training). The student failed to recover properly from the simulation and would not release the controls after I instructed him to do so. I quickly retarded the left mixture to Idle/Cutoff; but the aircraft was already exiting the runway onto the grass; destroying a runway light. I had given the student ground instruction on multi-engine aerodynamics; and we had discussed what to do in the event of engine failures; both on the ground and in flight. The student was using a checklist and had read aloud the proper procedures for recovering from an engine failure during the takeoff roll; and we had discussed it prior to the starting the engines and again prior to taking the runway. I learned that simulating an engine failure on the takeoff roll during the first flight is not the safest way to conduct flight training and that I should be more alert for students to improperly correct for adverse situations in order to conduct safer flight training. The airplane was mildly damaged; only propeller blades that needed replaced or filed down and re-balanced; and the aircraft was operational again within several days.

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.