What happened
On April 23, 2023, a Piper PA32-300 departed from Isla Mocha Aerodrome (SCIM) in the Biobío Region of Chile, bound for Cañete (SCNM). Prior to the flight, approximately 60 liters of fuel had been drained from each of the wingtip tanks and stored in metal drums at the airfield.
Shortly after takeoff, during the initial climb phase, the aircraft entered a left turn. During this maneuver, the engine lost power, causing the aircraft to lose altitude rapidly. The plane impacted the surface of the sea approximately 10 and 100 meters from the coastline. The accident resulted in four fatalities—the pilot and three passengers—while one passenger survived with injuries. The aircraft sustained severe damage.
The investigation
DGAC Chile investigators examined the aircraft's maintenance records, fuel levels, and the physical evidence at the crash site. While maintenance logs were up to date as of 44 days prior to the accident, the flight logs and maintenance logs were not recovered from the wreckage, preventing a full verification of the aircraft's status on the day of the event.
Analysis of the fuel system revealed that the fuel selector valve was positioned to the left wingtip tank. Because of the previous drainage, only a minimal amount of fuel (approximately 4.6 liters per tank) remained in those wingtip tanks. Investigators also examined the engine and propeller; inspections by the manufacturers, Lycoming and Hartzell, ruled out mechanical engine failure or propeller malfunction as the cause of the power loss.
Findings
- The engine stopped in flight due to a lack of fuel supply to the engine.
- The selection of the left wingtip tank as the primary fuel source was a critical factor, as this tank contained only a very low level of fuel following the pre-flight drainage.
- During the left turn after takeoff, the remaining fuel in the wingtip tank shifted toward the tip of the wing, interrupting the continuous flow of fuel to the engine.
- The low altitude and the phase of flight (initial climb) left the pilot with insufficient time and altitude to perform an engine restart or execute corrective maneuvers.
- The pilot likely failed to verify the fuel selector position and the actual fuel levels in the wingtip tanks against the cockpit indicators prior to departure.
Safety action
Following the investigation, the DGAC Chile recommended that operators strengthen procedures for verifying fuel selector positions and cockpit fuel indicators, specifically emphasizing the use of checklists. The authority also recommended that operators implement stricter management of fuel distribution and drainage procedures to ensure that the correct tanks are selected for takeoff.