What happened
On September 23, 2010, an Aero Commander AC-500, registration N100PV, was conducting a private flight from Isla Grande, Puerto Rico, to Santo Domingo, Dominican Republic. The aircraft was carrying two crew members and two passengers. While descending through 2,000 feet and approximately five miles from the runway of Las Américas International Airport (MDSD), the pilot experienced a sudden vibration and noted that both engines were stopping.
Despite communicating engine issues to the Approach Control, the pilot did not formally declare an emergency until the final stages of the approach, when it became clear the aircraft could not reach the runway. The aircraft performed a controlled descent into vegetation approximately one kilometer southeast of runway 35 head. The impact resulted in two serious injuries among the four occupants, while the aircraft sustained substantial damage, including structural deformation and the separation of the right engine.
The investigation
The CIAA investigation focused on the mechanical state of the fuel system and the communication between the flight crew and Air Traffic Control (ATC). Investigators examined the aircraft's fuel tanks, drains, and maintenance records. The investigation also reviewed ATC transcripts and interviewed witnesses.
Technical analysis revealed that the aircraft's fuel tanks were empty at the time of the crash. Investigators also examined the fuel filler neck, where they found evidence of fuel leakage. Furthermore, the investigation scrutinized the ATC response, noting that the controller initially interpreted the pilot's reports as a single-engine issue rather than a dual-engine failure, and failed to confirm an emergency status before transferring the aircraft to the Tower.
Findings
- The pilot operated the aircraft with a non-airworthy configuration, having replaced the missing fuel tank cap with duct tape.
- The use of adhesive tape allowed the fuel filler neck to remain inadequately sealed; aerodynamic forces created a siphon effect that gradually drained the fuel from the tanks.
- The dual engine failure was caused by fuel starvation.
- The pilot failed to declare an emergency promptly, despite recognizing the engine malfunctions during the descent.
- ATC personnel did not adequately prioritize the aircraft or verify the severity of the engine issues during the transition from Approach to Tower control.