Two helicopters were damaged by low-hanging cargo hooks which were blown upwards due to pilots flying at maximum speeds.
The incidents were revealed in a bulletin by the UK Air Accidents Investigation Branch (AAIB).
The first incident occurred in Cairngorms National Park on October 8. An almost identical incident occurred eight days later in Kettlewell, North Yorkshire, involving the same model of aircraft.
Both pilots, who were aged 60 and 66 at the time, landed the helicopters safely and were unharmed.
The bulletin concluded: "A safety bulletin was issued to all affected pilots and ground crew, highlighting the changes and stressing the need to adhere to the 80-knot speed limit, whilst being prepared to reduce speed further."
Both aircraft were operated by Inverness-based PDG Helicopters.
PDG worked on the opening scenes of Ridley Scott's sci-fi reboot Prometheus, which were filmed on the Isle of Skye.