Incident Description
Shortly after takeoff, witnesses observed the airplane in a high pitch-up attitude while yawing left and right. One witness, an airframe and powerplant mechanic, reported that the engine sounded as though it was not producing full power. After gaining approximately 100 to 200 feet above the ground, the airplane rolled into a 90-degree bank and descended into swampy terrain.
Post-Accident Examination
Flight control cable continuity was established. The carburetor had broken away from the intake manifold and was submerged in swamp water. Examination of the magnetos revealed that the right magneto timing was set at 8 degrees before top dead center, while the manufacturer's recommended setting is 26 degrees before top dead center. The left magneto timing was correctly set at the manufacturer's specification. The right magneto was retimed to the manufacturer's prescribed setting.
Engine and Carburetor Testing
After retiming, an engine runup was accomplished using the magnetos and a factory carburetor. The engine and carburetor were examined at their respective manufacturers; both were found to operate within the manufacturer's specifications.