§ 35.37 Fatigue limits and evaluation.

This section does not apply to fixed-pitch wood propellers of conventional design. (a) Fatigue limits must be established by tests, or analysis based on tests, for propeller: (1) Hubs. (2) Blades. (3) Blade retention components. (4) Components which are affected by fatigue loads and which are shown under § 35.15 to have a fatigue failure mode leading to hazardous propeller effects. (b) The fatigue limits must take into account: (1) All known and reasonably foreseeable vibration and cyclic load patterns that are expected in service; and (2) Expected service deterioration, variations in material properties, manufacturing variations, and environmental effects. (c) A fatigue evaluation of the propeller must be conducted to show that hazardous propeller effects due to fatigue will be avoided throughout the intended operational life of the propeller on either: (1) The intended airplane by complying with § 23.2400(c) or § 25.907 of this chapter, as applicable; or (2) A typical airplane.