A Method Of Determining Safe Service Life For Helicopter Components

Methods used by Bell Helicopter Textron to determine safe service lives for most helicopter components have been used for many years, and have proven to be reliable. In general, these methods follow those outlined in FAA Advisory Circular 20-95. To determine the fatigue life of a component it is essential that the following information is known: Fatigue strength characteristics of the component; The stresses associated with normal flight maneuvers; and The frequency of occurrence of those maneuvers. The methods used by Bell are illustrated by the solution to the hypothetical fatigue life problem formulated by the Conference Technical Committee.