What happened
On 19 January 2019, a DJI Matrice 210 was being operated in Clevedon, Somerset, for the purpose of emergency services operations. The flight was a planned check flight intended to verify the integrity of a camera following a previous day's flight, specifically looking for signs of water intrusion.
During the mission, the aircraft took off with fully charged batteries and completed its initial systems checks. The pilot navigated the drone to a position approximately 500 m north of the takeoff and landing site, reaching an altitude of 120 m. At the time, weather conditions included light drizzle and a steady wind of 16 mph, though visibility remained good. After hovering for roughly five minutes to perform the necessary inspections, the pilot began the return leg toward the takeoff site. However, when the aircraft was approximately 360 m from its landing point, it suffered a sudden vertical descent, impacting an empty field. The impact resulted in the aircraft being destroyed.
The investigation
Following the accident, the recorded flight data was sent to the manufacturer for detailed analysis. The investigation focused on the mechanical and electronic state of the quadcopter at the moment of the descent.
Findings
- The investigation established that the No 2 (front left) electronic speed controller had experienced a failure.
- This failure was likely caused by water ingress into the component, which was a significant risk given the light drizzle present during the flight.