What happened
On May 29, 2025, at approximately 07:05 local time, a Cessna A188B, registration HK1817, was involved in a fatal ramp accident at the El Tesoro Aerodrome in Trinidad, Casanary, Colombia. The aircraft, performing specialized agricultural spraying operations, was parked on the apron with its engine running at idle power to facilitate efficient refueling and chemical replenishment.
While a company technician was inspecting the left fuel tank, a third-party worker—responsible for preparing chemical mixtures for the farmer—approached the aircraft from the rear. The individual attempted to communicate with the technician and, while moving away from the aircraft, entered the propeller's rotation arc. The rotating propeller blades struck the worker, resulting in one fatality.
The pilot, who remained in the cockpit awaiting clearance to taxi, reported a heavy impact followed by a sudden change in engine RPM. The pilot immediately shut down the engine and evacuated the aircraft. The propeller sustained minor damage, including small indentations at the blade tips.
The investigation
The Colombian accident investigation authority (DIACC) examined the sequence of events and the operational environment. The investigation established that the aircraft was operating under visual flight rules (VMC) in daylight.
Investigators noted that while the operator had posted safety signs regarding minimum approach distances, the ground markings and demarcations for the chemical mixing area and the apron were deficient. Furthermore, although the operator had previously conducted informal safety briefings with external personnel, there was no structured or documented training program for non-aeronautical staff involved in the ground support process.
Findings
- The primary cause of the accident was the impact of rotating propeller blades with ground personnel during refueling operations.
- The event was triggered by an unsafe act involving non-aeronautical personnel who deliberately entered the aircraft's critical area while the engine was running.
- The worker's actions were characterized by an excess of confidence and an underestimation of the propeller's rotation diameter.
- The site lacked adequate physical demarcation and signage to clearly define restricted operational zones for external workers.
Safety action
- The operator is required to update its Operations Manuals and policies to include documented, formal briefings and training for chemical mixing personnel to mitigate the risk of unauthorized approach to the aircraft's critical area.
- The operator must implement a program for the re-demarcation and improved signaling of the apron and chemical mixing areas to enhance situational awareness for all personnel on the ground.