AAIB investigation to DJI Matrice 210 (UAS, registration n/a)
Motor failure at 220 ft agl, crashed into a stream, Old Lane, Little Hulton, Manchester, 29 January 2019.
Summary:
The unmanned air system (UAS) had been used to carry out an aerial search during a police operation. On completion, it was being flown back to the launch point, when, without warning, it rapidly spiralled to the ground. It crashed into a small stream and was extensively damaged. An examination of the UAS data after the accident found the cause was a propulsion error in one of its four motors.
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