What happened
On February 17, 2023, a Bell 206 B3 helicopter, registration HK4750, was conducting a VFR sightseeing flight near Barranquilla, Colombia. The flight path included a route between Ernesto Cortissoz Airport in Soledad and Puerto Colombia. The aircraft was carrying one pilot and two passengers.
After departing normally and climbing to 500 feet, the engine suddenly failed approximately five minutes into the flight. The pilot executed an autorotation maneuver and identified a suitable field for an emergency landing. While the pilot managed a controlled touchdown, the uneven slope of the terrain caused the aircraft to lose stability upon impact. The helicopter rolled onto its side, performing two longitudinal turns on its right side, which caused the main landing gear tubes to collapse and the tail rotor assembly to detach.
Following the impact, the occupants evacuated the aircraft. The pilot sustained serious injuries that hindered his ability to move his lower limbs, while one passenger sustained serious injuries and the other sustained minor injuries. Shortly after the evacuation, local residents interacted with the wreckage, which triggered a fire that consumed approximately 90% of the aircraft.
The investigation
The GRIAA investigation focused on the cause of the engine failure and the subsequent loss of control. Investigators examined the aircraft's maintenance records, fuel quality, and weight and balance. Fuel samples taken during refueling prior to the flight showed no signs of contamination.
However, the investigation faced significant challenges regarding the physical evidence. After the emergency services and police withdrew from the scene due to security concerns, local individuals removed critical components from the wreckage. The engine, transmission, and main rotor blades were stolen from the site, likely to be sold as scrap. Consequently, investigators were unable to perform a physical inspection or functional test of the power plant to determine the exact nature of the failure.
Findings
- The primary cause of the accident was an unidentified sudden engine failure during level flight.
- The aircraft's rollover was caused by the uneven slope of the landing site, which led to a loss of stability after the initial touchdown.
- The engine failure was likely due to an internal mechanical failure, such as a compressor blade release or a failure in the hot section, though this could not be confirmed due to the theft of the engine.
- The destruction of the aircraft was exacerbated by a post-crash fire caused by third-party interference with the wreckage.
Safety action
- The air operator was recommended to strengthen coordination mechanisms within its Emergency Action Plan to better secure accident scenes.
- The Colombian Civil Aviation Authority (Aerocivil) was advised to notify the operator of Ernesto Cortissoz Airport to improve their emergency protocols, specifically regarding coordination with public forces to prevent the theft of wreckage and evidence.