What happened
During a multi-leg ferry flight intended to deliver a single-engine turbine-powered airplane from Puerto Rico to Brazil, the pilot elected to fly a direct route toward Grenada. This path took the aircraft away from the safety of the island chain, placing the flight far from land. While cruising at 27,000 feet over open water, approximately 119 miles from a suitable landing site, the engine suffered a complete loss of power. During the failure, the pilot observed the engine torque drop to zero, followed by intense vibrations and smoke emitting from the engine.
In response to the engine failure, the pilot performed a ditching maneuver. The aircraft subsequently sank into the ocean and was not recovered. Both the pilot and a pilot-rated passenger were successfully rescued from the water by a French Navy helicopter.
Findings
Investigations into the incident revealed several deviations from standard operating procedures. The pilot had chosen a direct route over open water as a calculated risk, despite the fact that staying closer to the islands would have kept the aircraft within a safe gliding distance. Additionally, the aircraft was being operated at weights exceeding the manufacturer's published limitations, and no performance data was available for such an overweight configuration.
Further analysis of the engine's operation showed that the engine was being run at excessive torque settings. Prior to the failure, torque readings were reported between 937 and 980 ft-lbs, both of which exceeded the maximum limits specified in the Pilot's Operating Handbook. Operating the engine beyond these recommended power settings can lead to accelerated component distress. Furthermore, the aircraft was not equipped with fuel heaters, yet it was fueled without the addition of a fuel icing additive despite the high-altitude flight plan.