What happened
On the evening of 4 May 2023, a DJI Mavic 2 Enterprise with registration ZT-XSD was deployed for a security surveillance mission at Mondi Mill Bay, KwaZulu-Natal. The operation was being conducted under beyond visual line of sight (BVLOS) regulations. Following a standard pre-flight inspection that showed no issues, the pilot launched the aircraft with 99% battery power. Shortly after takeoff, an unusual noise was heard, and the aircraft began to spiral downward. The drone crashed approximately 100 metres from the launch site, resulting in substantial damage to the aircraft. No injuries were reported during the incident.
The investigation
SACAA AIID examined the circumstances surrounding the flight and the technical performance of the aircraft. The investigation reviewed the pilot's credentials, noting a valid Remote Pilot Licence and sufficient flight experience on this specific type. The aircraft's maintenance records, including its most recent periodic inspection, were also verified. To determine the cause of the descent, investigators analyzed the operator's post-accident technical assessment and the aircraft's flight logs.
Findings
The investigation established that the primary cause of the accident was an electronic speed control (ESC) unit malfunction. This failure directly impacted the operation of one of the motors, destabilizing the aircraft and forcing it into a high-speed spiral toward the ground. While the specific reason for the ESC failure could not be determined, the technical malfunction was the decisive factor in the loss of flight control.