What was found
AT 1,500 MSL, BOTH IGNITION SOURCES FAILED TO PRODUCE HIGH VOLTAGE TO THE SPARK PLUGS RESULTING IN THE REDUCTION OF ENGINE POWER AND THE ENGINE STOPPED ROTATION. THE AIRCRAFT CRASHED IN AN OPEN FIELD WITH MINOR DAMAGE. BOTH COILS' NEGATIVE TERMINALS EXHIBIT WIRES CONNECTED TOGETHER AT A SINGLE POLE SWITCH ATTACHED TO THE ELECTRONIC TACHOMETER THAT HAD AN INTERNAL GROUND FAULT THAT CAUSED THE COILS TO OVERHEAT, AND INTERNALLY FAIL TO PRODUCE HIGH VOLTAGE IGNITION TO THE SPARK PLUGS.