Synopsis
On 23 November 2021, a Bell 206B-3 helicopter registered as 9M-AWD was involved in a serious incident at Kota Marudu, Sabah, Malaysia. The aircraft had five persons on board: one pilot and four medical officers. While returning from a Flying Doctor Service tasking, the pilot decided to land after noticing an improperly secured left-hand aft passenger door. During approach to a football field at SMK Kota Marudu, the helicopter struck an electrical wire. The wire snapped, and the aircraft landed safely. A post-flight inspection revealed damage to the main rotor hub.
Factual Information
History of the Flight
On the day of the incident, 9M-AWD was returning to Kota Kinabalu International Airport (BKI) after completing a Flying Doctor Service mission. While transiting at 3,000 feet, the pilot observed that the left-hand aft passenger door was not properly secured. Considering this a safety hazard, the pilot decided to land immediately. During descent, the pilot performed checks for a confined area landing and selected a football field at SMK Kota Marudu as the landing point. As the helicopter descended to about 20 feet, the pilot spotted an electrical wire directly ahead running across the center of the field. Due to the aircraft's momentum and proximity to the ground, evasive action was not possible, and the helicopter struck the cable. Some vibration was felt as the cable snapped; the pilot continued to land safely. All occupants disembarked without incident.
Injuries to Persons
None of the five occupants sustained any injuries.
Damage to Aircraft
The helicopter experienced damage to the main rotor hub due to the wire strike. Visual assessment of the damage is documented in the report appendix.
Other Damages
The electrical wire that was struck snapped, and one of its supporting poles was left leaning slightly due to the impact.
Personnel Information
The pilot held a Commercial Pilot License (CPL) and was properly qualified for the task.
Aircraft Information
The Bell 206B-3, serial number 2351, was owned and operated by Layang-Layang Aerospace Sdn Bhd, a regional charter airline based in Sabah, Malaysia.
Meteorological Information
Weather was clear with scattered clouds and light, variable wind conditions.
Communications
No distress calls were made via radio. The pilot informed the operator's Flight Operations Manager by phone.
Flight Recorders
The Bell 206B-3 was not equipped with flight data or cockpit voice recorders, nor was it required by regulation.
Wreckage and Impact Information
Visual examination at the site confirmed damage to the main rotor hub from the wire strike. The wire and one support pole were damaged.
Medical and Pathological Information
No injuries were reported.
Fire
There was no post-impact fire.
Survival Aspects
All occupants egressed normally without difficulty.
Analysis
The pilot had performed checks for confined area operations during the descent from 3,000 feet but did not detect the wire across the football field until too late. The wire, slightly less than a centimeter in diameter, was strung between two poles at about 20 feet along the field's centerline. The report notes that such a wire is difficult to spot from a moving aircraft, even from 500 feet. The ultimate responsibility for the incident was placed on the pilot. Additionally, the incident was precipitated by the improperly secured left-hand aft door; as the only aircrew, the pilot was responsible for ensuring all doors were secure before flight.
Conclusions
Landing at unprepared landing points carries inherent risk. The incident serves as a reminder to maintain vigilance in such situations. The occurrence was classified as a Collision with an Obstacle during Take-Off or Landing (CTOL).
Safety Recommendations
The helicopter operator was instructed to remind all its helicopter pilots of the dangers of landing at unprepared landing points.