Study on the Calculation Method of Operational Availability of Civil Aircraft

Based on the comprehensive consideration of aircraft scheduled maintenance factors, unscheduled maintenance factors and the level of aviation spares guarantee, this paper develops the calculation method and process of aircraft-level and system-level availability indexes for civil aircraft, and proposes a method to allocate availability based on the number of unscheduled removals in a hierarchical manner. The calculation method can not only guide the determination of aircraft-level and system-level operational availability indexes for civil aircraft, but also be applied to the assessment of civil aircraft operational availability in the operation phase, which is of great significance to ensure the utilization rate of civil aircraft and reduce the operation cost.