Positive locking device

A positive locking device is a device used in conjunction with a fastener in order to positively lock the fastener. This means that the fastener cannot work loose from vibrations. The following is a list of positive locking devices:

• A split beam nut
• A castellated nut and a split pin
• A hex nut or cap screw and a tab washer
• A hex nut or cap screw and a lock plate
• Safety wiring with various types of fasteners

• 
  A locking plate
• 
  A tab washer

• "7. Aircraft Hardware, Control Cables, and Turnbuckles" (PDF). AC 43.13-1B - Acceptable Methods, Techniques, and Practices - Aircraft Inspection and Repair. 8 September 1998. Retrieved 2012-12-11.