Flight History
On 4 May 2019, a Robinson R44 helicopter, registration HK4449, operated by Aeroexpress S.A.S., was conducting a non-scheduled passenger transport flight. The helicopter departed from Enrique Olaya Herrera Airport (SKMD) in Medellín at 10:24 local time with two passengers, landing at the Helitours heliport in Guatapé at 10:48. After a hot refueling and passenger exchange, three passengers boarded for a local flight. At 10:58, during the initial takeoff run, the pilot felt a strong descent after traveling approximately 23 m at 10 knots. The pilot aborted the takeoff with a pronounced flare, causing the main rotor blades to strike the tail cone. The helicopter fell to the ground without rolling over or rotating. The pilot performed emergency procedures, shut down the engine, and the four occupants evacuated without injury.
Injuries and Damage
No injuries occurred among the pilot and three passengers. The helicopter sustained major structural damage, primarily the separation of the tail cone from the fuselage due to the rotor strike. No post-impact fire occurred.
Aircraft Information
The helicopter was a Robinson R44, serial number not specified in the report, with registration HK4449. It was operated by Aeroexpress S.A.S. The engine was a Lycoming, and the right magneto was found to be inoperative with electrical continuity to ground. Maintenance records indicated a recent unauthorized repair to the magneto's P-lead by the Repair Aeronautical Workshop (TAR).
Maintenance Findings
The investigation revealed that the right magneto had electrical continuity to ground, rendering it inoperative. The P-lead of that magneto had been repaired by the TAR in a manner not authorized by the manufacturer. This repair was considered inadequate maintenance.
Probable Cause
The accident resulted from:
- Main rotor blades striking the tail cone structure after aborting the takeoff.
- Power loss during takeoff caused by an inoperative right engine magneto with electrical continuity to ground.
- Inadequate maintenance practices by the Repair Aeronautical Workshop (TAR) in performing an unauthorized repair to the P-lead of the right magneto that failed.