Nuts
Aircraft nuts are made in a variety of shapes and sizes. They are made of cadmium plated carbon steel, stainless steel, or anodized 2024T aluminum alloy, and may be obtained with either right or left-hand threads. No identifying marking or lettering appears on nuts. They can be identified only by the characteristic metallic luster or color of the aluminum, brass, or the insert when the nut is of the selflocking type. They can be further identified by their construction.
Aircraft nuts can be divided into two general groups: Nonselflocking and selflocking nuts. Nonselflocking nuts are those that must be safetied by external locking devices, such as cotter pins, safety wire, or locknuts. Selflocking nuts contain the locking feature as an integral part. From castellated and wing nuts to elastic stop and Boots self-locking nuts, our aircraft nut guide explains each type and how AN and MS part numbers are coded. To match threads, see our page on thread series and fit classes.
