Positive locking device

The word safetying is a term universally used in the aircraft industry.

Briefly, safetying is defined as: "Securing by various means any nut, bolt, turnbuckle etc., on the aircraft so that vibration will not cause it to loosen during operation."

These practices are not a means of obtaining or maintaining torque, rather a safety device to prevent the disengagement of screws, nuts, bolts, snap rings, oil caps, drain cocks, valves, and parts.

Three basic methods are used in safetying; safety-wire, cotter pins, and self-locking nuts.

Safety wire must be installed in a manner that will prevent the tendency of the part to loosen.