What happened
At approximately 07:55, Flight 901A departed from the ramp in Vieques with eight passengers on board. During taxiing toward the takeoff end of runway 09, the pilot communicated with UNICOM, receiving confirmation that no other aircraft were operating in the vicinity. An eyewitness at the airport observed the aircraft type performing a standard initial climb following takeoff. However, as the plane entered a left-hand crosswind departure pattern at an altitude of roughly 200 feet above the sea, it appeared to experience a loss of engine power.
The observer noted that the aircraft briefly climbed an additional 50 feet while maintaining a nose-high attitude and that the engines seemed to regain power momentarily before the plane descended into the ocean. The impact occurred approximately 1/2 mile offshore, north of the departure end of runway 09. The crash resulted in nine fatalities and the total destruction of the aircraft.
Findings
Investigations determined that the primary cause was the pilot's improper execution of emergency procedures following a loss of power in the left engine. This power loss was triggered by water contamination within the aircraft fuel system. The presence of water was attributed to the failure of the Puerto Rico Ports Authority to clear excess water from the airport's underground fuel tank prior to fueling.
Additional contributing factors included:
- The pilot lacked the necessary certification for this specific flight and had not received adequate training.
- Inadequate procedures were used by the crew to detect water in the fuel tanks.
- The aircraft was operated in an out-of-weight and balance condition.
- Regulatory oversight issues involving the FAA's application of Part 135 rules and insufficient surveillance of the air carrier.