Kern Valley Airport
Aircraft Accident/Incident Report

Kernville, California 93238
Sunday, August 17, 1997 17:44 PDT

Seconds after takeoff, the engines lost partial power. Witnesses saw black smoke trailing from the airplane. Unable to climb, the pilot ditched and sank in 20-foot-deep water, 1.25 miles from the airport. During the month preceding the accident, black smoke had been observed trailing from the airplane on two other occasions, but no evidence of maintenance was noted in the logbooks. The airplane was recovered and examined. The engines were placed into a test cell and run and numerous maintenance related deficiencies were found. Although full power was obtained, the fuel flow rates to both engines exceeded design specifications, thus creating overly rich mixtures and black smoke. Additionally, the right engine's left magneto internally arced, and 5 of the 12 spark plugs were worn beyond limits. The density altitude was computed at 4,300 feet. Also, the maximum certificated gross weight was exceeded by at least 160 pounds, and the center of gravity was 1.09 inches aft of the rear limit. The pilot said he had not asked for a weather briefing prior to departure, nor had he performed weight and balance computations. The fare-paying passengers had not been advised to secure their shoulder harnesses prior to takeoff, and their aft loaded baggage was unsecured because of the previous removal of the tie down straps. The pilot did not provide the Safety Board with evidence of his recent flying currency or complete the required report form. The passengers chartered the flight in response to the operator's yellow page advertisement for such availability. The operator did not possess a 14 CFR 135 certificate, and the FAA's surveillance of the FBO was nil.

The partial loss of engine power due to the operator's inadequate engine maintenance relating to excessively rich mixtures (high fuel flow rates) and spark plug/magneto deficiencies. Contributing factors were degraded climb performance resulting from the high density altitude and the airplane loading which exceeded maximum weight and aft center of gravity limits.