What happened
On 26 September 2018, a Yuneec Typhoon H4-80 was being operated at RAF St Athan, Wales, to provide aerial photography for a multi-agency exercise. The unmanned aircraft had been performing several successful flights earlier that day. Before the final flight of the session, the pilot installed a new, fully charged battery and performed all necessary pre-flight inspections, which revealed no issues.
After approximately 12 minutes of flight time, the aircraft was in the process of returning to its landing zone. As it reached an altitude of roughly 30 feet, the drone suddenly tilted forward and struck the ground. The impact resulted in the aircraft being damaged beyond economic repair. There were no injuries to personnel, and no damage was sustained by vehicles or ground property.
The investigation
Following the incident, the aircraft was sent to the manufacturer's agent for technical evaluation. These tests did not reveal any pre-existing mechanical or electronic defects. Analysis of the data recovered from the Yuneec Typhoon H480 indicated that the aircraft did not trigger any error messages during the flight. However, the logs revealed that a loss of electrical power occurred when the aircraft was at a height of 37 feet.
Findings
- The investigation established that the crash was preceded by a sudden loss of electrical power during the descent.
- The manufacturer noted that the Yuneec Typhoon H480 can continue to operate even if the battery is not completely secure or fully seated in its compartment.
- It was noted that previous incidents involving this model have occurred when an insecure battery moved during flight, leading to power interruptions.