What are safety wire and cotter pins primarily used for in aircraft hardware?

Safety wire and cotter pins are primarily used to prevent fasteners, such as nuts and bolts, from loosening due to vibration or movement in aircraft operations. By securing these fasteners, they help maintain proper assembly and ensure that critical components remain intact during flight. This is particularly important in aviation, where any component failure can lead to serious consequences. Safety wire loops through holes in fasteners and is twisted to create tension, while cotter pins are inserted through a hole in a bolt or a nut to lock it in place. The use of these hardware solutions minimizes the risk of parts coming loose, enhancing overall safety and reliability in aircraft systems.