TM-5-5420-279-10
Table A. 1 Inspection and action requirements (continued)
Inspection
Location
Time Interval
Action
Method
When CrackFirst gauge
Visual
Check for transverse
Zone A - Top side of
has cracked across
(vertical) cracks across side
bottom chord at weld
central band between
skin to bottom chord weld.
to side skin
12 mm holes until gauge
Remove from service if any
has cracked completely.
cracks longer than 25 mm
are found.
When CrackFirst gauge
Visual
Check for cracks at weld
Zone A - Weld toes
has cracked across
toes in vertical direction.
of blocks for fatigue
central band between
Remove from service if any
monitoring gauges
12 mm holes until gauge
cracks longer than 25 mm
has cracked completely.
are found.
continued
A-4
