Page 208 2
nd
Edition – Rev 0
02-40
SAFETYING – MAINTENANCE PRACTICES
Securing With Cotter Pins
Cotter pins are used to secure such items as bolts, screws, pins, and shafts. The diameter of
the cotter pins selected for any application should be the largest size that will fit consistent
with the diameter of the cotter pin hole and/or the slots in the nut. Cotter pins must not be
reused on aircraft.
In using the method of cotter pin safetying, as shown in Figures below, ensure the prong, bent
over the bolt, is seated firmly against the bolt shank, and does not exceed bolt diameter. Also,
when the prong is bent over the nut, ensure the bent prong is down and firmly flat against the
nut and does not contact the surface of the washer.
Figure 11. – Securing with cotter pins
Figure 12. – Alternate method for securing with cotter pins