To: Vfr
Aircraft manufacturers in general will establish the level of wear, abrasion and impact damage for propellers and rotor blades. They will also establish the extent of acceptable wear and or damage and the location of the damage or wear. They will also establish the corrective procedures to be used to remove or repair the damage or wear. They will also establish the blade removal criteria and whether the blades can be repaired at the factory or, if they should be scrapped.
It does not require a lot of time for a dent or nick to manifest itself into a crack and total failure. See my post on the CG HO3S blade fracture and the failure of the blade on the Marine HRS. Both on the Robinson blade thread.
