Accident Description
The airplane was operated as part of a school's aviation program with a flight instructor and student pilot on board. Shortly after takeoff, the engine lost power and the aircraft impacted a lake. Witnesses reported hearing the engine sputtering, a momentary restart, and then a complete loss of engine power while the airplane was maneuvering at an altitude of approximately 150 to 200 feet above ground level.
Structural and Systems Examination
Both wings exhibited leading edge crushing and vertical separation from the fuselage, consistent with a low-speed, shallow pitch impact attitude. The propeller did not display signs of bending or twisting. The flaps were found in the retracted position. Cockpit switches were in positions contrary to those called for in the emergency landing procedures checklist for the airplane.
Engine and Ignition System Findings
Examination of the engine ignition system revealed that the left magneto timing was approximately 30 to 35 degrees before top dead center, and the impulse coupling was unwound. The right magneto timing was not specified.
Maintenance Records
The airplane had completed an annual inspection on the day of the accident. Engine logbook records showed an entry dated August 9, 2004, stating, "changed left magneto with new magneto model number 4371." There was no annotation of the serial number for the left magneto, and no further entries documented an overhaul of either magneto. No serviceable tag was associated with the replacement left magneto. At the time of the annual inspection, the left magneto had accumulated 406 hours since installation, and the right magneto had accumulated 1,429 hours since its last overhaul, based on logbook entries. According to the magneto manufacturer's service bulletin, these magnetos require overhaul every 500 hours.
Additional Observations
Inspection of the remaining airplanes used in the school's aviation program revealed numerous maintenance-related discrepancies, including the use of unairworthy parts. Upon recovery of the accident airplane, the entry door was found in the latched closed position.