Currently in Poland about 2,500 different engine types are installed on the aircraft. In the years 2008-2016 powerplants failures caused nearly 600 aviation events. Aborted flight or emergency landing, especially in the case of aircraft powered by a single piston engine occurred. The objective of the article was to determine the failure causes and assessment of their impact on the flight safety. Engine faults were assigned to particular types of powerplants, for example turboshaft, piston, etc. Causes of the failures were examined, assigning ATA chapter to each of them. Also human factor was taken into account. According to the ICAO methodology, aviation safety engine systems essential for flight safety and theirs impact on the safety risk was determined. The results of the analyzes presented in this article are useful for managing the national aviation safety and supervising SMS in aviation organizations. The article shows that preventive measures to raise the level of aviation safety should be taken. This is the first comprehensive analysis of the powerplants failure causes and an evaluation of their influence on the level of aviation safety in Poland.