In this article, the flight spherical risk of P3F aircraft is evaluated using the FMEA method. For this purpose, first a complete study of the equipment and systems related to the flying sphere of this aircraft was done. Then the potential failure modes for each of the systems and the spherical flight error were determined. In the following, the potential effects of each of these failure modes were determined and then the causes of each of them were determined. Listing the current controls in order to identify each of these failures, calculating the priorities and importance of each risk are the next steps of this thesis. At the end, preventive and corrective measures will be proposed with the approach of reducing flight risk. In this research, using the RPN relationship, a risk number was assigned to each of the aircraft systems, and the systems with the highest probability of accidents were determined, based on the results of the three engine indicator systems, the altimeter and the speedometer of the aircraft, which have the highest probability of risk in flight.