FAA Advisory Circular 43.13-1B
Acceptable Methods, Techniques, and Practices
Aircraft Inspection and Repair
AC 43.13-1B | 7. Aircraft Hardware, Control Cables, and Turnbuckles | 4. Nuts | 7-67. Castellated Shear Nut (AN320)
9/8/98
AC 43.13-1B
7-67. CASTELLATED SHEAR NUT
(AN320). The castellated shear nut is de-
signed for use with hardware subjected to
shear stress only.
7-68. PLAIN NUT (AN315 AND AN335).
The plain nut is capable of withstanding large
tension loads; however, it requires an auxiliary
locking device, such as a checknut or safety
wire. Use of this type on aircraft structures is
limited.
7-69. LIGHT HEX NUTS (AN340 AND
AN345). These nuts are used in nonstructural
applications requiring light tension. Like the
AN315 and AN335, they require a locking de-
vice to secure them.
7-71. WINGNUTS (AN350). The wingnut
is used where the desired torque is obtained by
use of the fingers or handtools. Wingnuts are
normally drilled to allow safetying with safety
wire.
7-72. SHEET SPRING NUTS (AN365).
Sheet spring nuts are commonly called speed
nuts. They are used with standard and sheet
metal self-tapping screws in nonstructural ap-
plications. They are used to support line and
conduit clamps, access doors, etc. Their use
should be limited to applications where they
were originally used in assembly of the air-
craft.
7-73.7-84. RESERVED.
7-70. CHECKNUT (AN316). The checknut
is used as a locking device for plain nuts,
screws, threaded rod ends, and other devices.
Par 7-67
Page 7-13 (and 7-14)