Abstract The result of operating the military helicopters in a dusty environment is a loss of performance and premature failures of gas paths of the engines. The efficient protection of the power plant against dust ingestion is tough, especially in the desert. The article summarises the experience accumulated while operating the military helicopters under harsh conditions in Poland and during foreign missions. There were characterised the types of conducted missions, operated helicopters, protection methods of engines and common failures. It was stated that the performance of TV3-117 engines and their particle separation systems was insufficient in the mountains and on the desert (Iraq and Afghanistan). The deterioration of gas paths resulted in the loss of helicopters’ performance and substantially contributed to the few aircraft incidents. The experience gained during foreign missions is used in training the crews and ground personnel and in the programmes of modernisation and renewal of the helicopter fleet.