Almost 1,700 properties were left without electricity after an unaware helicopter pilot struck a pylon in Aberdeenshire, a report has revealed.
The incident occurred in September 2022, when the 73-year-old pilot conducting a survey for precious minerals using an electromagnetic monitoring loop.
The sensor struck a 26ft-high electricity supply pylon at Auchmacoy, but the pilot was unaware.
As a result of the collision, the power cables were severed and power supply to 1,682 properties in the area was interrupted.
An investigation by the Air Accidents Investigation Branch (AAIB) said the pylon had not been identified as a possible obstacle.
In a report, the AAIB said the pilot had reduced speed – however, in doing so, the helicopter lost height and the underhanging equipment collided with the pylon.
The pilot, who has more than 20,000 hours of flying under his belt, stated that he was unaware that the antenna had struck the pylon, and so continued the survey as planned.
The rest of the survey was cancelled after the incident, and the Civil Aviation Authority issued the operator with enhanced requirements for any similar operation in future.
These included a more detailed risk assessment, the use of an observer in the aircraft, as well as digital mapping with obstruction overlay to be used while planning and while in flight.