FAA Advisory Circular 43.13-1B
Acceptable Methods, Techniques, and Practices
Aircraft Inspection and Repair
AC 43.13-1B | 4. Metal Structure, Welding, and Brazing | 4. Metal Repair Procedures | 4-58. Repair Methods and Precautions for Aluminum Structure
9/8/98
AC 43.13-1B
TABLE 4-9. Number of rivets required for splices (single-lap joint) in bare 2014-T6, 2024-T3, 2024-T36, and
7075-T6 sheet, clad 2014-T6, 2024-T3, 2024-T36, and 7075-T6 sheet, 2024-T4, and 7075-T6 plate, bar, rod, tube,
and extrusions, 2014-T6 extrusions.
Thickness
“t” in
inches
.016
.020
.025
.032
.036
.040
.051
.064
.081
.091
.102
.128
No. of 2117-T4 (AD) protruding head rivets required
per inch of width “W”
Rivet size
3/32
1/8
5/32
3/16
1/4
6.5
4.9
-
-
-
6.9
4.9
3.9
-
-
8.6
4.9
3.9
-
-
11.1
6.2
3.9
3.3
-
12.5
7.0
4.5
3.3
2.4
13.8
7.7
5.0
3.5
2.4
-
9.8
6.4
4.5
2.5
-
12.3
8.1
5.6
3.1
-
-
10.2
7.1
3.9
-
-
11.4
7.9
4.4
-
-
12.8
8.9
4.9
-
-
-
11.2
6.2
No. of
Bolts
AN-3
-
-
-
-
-
3.3
3.3
3.3
3.3
3.3
3.4
3.2
NOTES:
a. For stringers in the upper surface of a wing, or in a fuselage, 80 percent of the number of rivets shown in the table
may be used.
b. For intermediate frames, 60 percent of the number shown may be used.
c. For single lap sheet joints, 75 percent of the number shown may be used.
ENGINEERING NOTES:
a. The load per inch of width of material was calculated by assuming a strip 1 inch wide in tension.
b. Number of rivets required was calculated for 2117-T4 (AD) rivets, based on a rivet allowable shear stress equal to
40 percent of the sheet allowable tensile stress, and a sheet allowable bearing stress equal to 160 percent of the sheet
allowable tensile stress, using nominal bolt diameters for rivets.
c. Combinations of sheet thickness and rivet size above the underlined numbers are critical in (i.e., will fail by) bearing
on the sheet; those below are critical in shearing of the rivets.
d. The number of AN-3 bolts required below the underlined number was calculated based on a sheet allowable tensile
stress of 70,000 psi and a bolt allowable single shear load of 2,126 pounds.
Par 4-58
Page 4-37