What happened
During a multiengine instruction flight, a certified flight instructor was conducting training with a student pilot. The aircraft was operating in the traffic pattern at approximately 800 feet above ground level following several completed touch-and-go landings.
To simulate an engine failure, the instructor utilized a method of closing the mixture to mimic an inoperative engine, allowing the student to practice control and propeller feathering procedures before returning the mixture to full rich. During the downwind leg of the pattern, the instructor closed the mixture on the left engine. As the pilot turned the aircraft from base to final, the airspeed decreased, causing the airplane to roll sharply to the left and lose altitude.
The instructor reduced both throttles and managed to regain control of the aircraft; however, the plane collided with the roof of one house, bounced across a second roof, and finally came to rest on top of a third house. There were no injuries reported in the accident.
The investigation
A post-crash inspection of the engine and airframe was conducted. The examination found no mechanical anomalies that would have prevented the normal operation of the aircraft.