On August 18, 1996, approximately 1030 Pacific daylight time, a Piper PA-20, N150KS, sustained substantial damage during a forced landing after a loss of engine power while climbing out at Mulino, Oregon, during a series of touch-and-go landings. The student pilot, the sole occupant, was uninjured. Visual meteorological conditions prevailed at the time of the accident. No flight plan was filed for the flight. The pilot stated that while practicing touch-and-go landings, he was climbing out on his fifth touch-and-go, when the engine quit at about 150-200 feet above ground level. He said that up until the time the engine failed all instrument indications were normal, and the loss of power was sudden. The pilot stated that he pushed the nose down to prevent a stall and set the airplane down approximated 60-70 feet from the end of the runway. At that point, his groundspeed was too great to prevent the aircraft from going off the end of the runway. Less then 100 feet from the end of the runway is a sheer drop into the Mulino river. He said that full left braking failed to turn the aircraft because of excessive speed. He stated that he was forced to push the yoke forward while applying both brakes full to flip the aircraft on its back, in order to prevent going over the cliff. The airplane came to a rest approximate 30 feet from the edge. After recovery, the engine was test run in the aircraft and operated normally. The fuel tanks had been filled within the previous hour or so of flight time. No anomalies were found to explain the loss of engine power.