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Inlet Cone Inspection
Figure 601
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(b) Examine the inner surface of the inlet cone segments for visual cracks or delamination.
NOTE: Impact damage to outer surface of cone segment which
____ causes visible cracking or delamination of inner surface indicates major structural damage.
Inlet cones which have been subjected to bird strike, ice ingestation, or the use of impact tools in removal of installation are particularly susceptible to this type of damage.
1) If the inlet cone has structural damage, replace the inlet cone (AMM 72-31-01/401).
(c) Continue-In-Service Limits
1) The FOD visual limits of the external cone surface are given as follows: a) The damage that follows is permitted if it does not
cause crazing with the primary path to the inner surface of the cone:
1.
Small paint particles
_
2.
Dents
_
3.
Scratches
_
4.
Chipping
_ b) If there are cracks through the composite material on a surface location, you must replace the inlet cone.
c) Cracks are premitted in the black protective paint but must not progress into the composite material and must be within the limits that follow:
1.
Maximum crack length is 12.0 inches (304.8 mm) for
_
each crack.
2.
A maximum of 10 cracks are permitted for each inlet
_
cone.
3.
The cracks must be in the resin rich areas and must
_ not go into the composite material. Find the correct crack depth by lightly sanding the surface with Emery Paper (P05-055).
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4.
The cracks must not cause delamination.
_
5.
The end of the crack must be a minimum of 2.0
_ inches (50.80 mm) away from the trailing edge.
2) The visual delamination limits of the external cone surface are given as follows: a) No delamination or peeling is permitted on the composite material surface. b) FOR ENGINES WITH PN 749629; Erosion or peeling of the black protective paint on the cone (front) segment is permitted up to 50% of the surface area, but the part must be replaced at the next scheduled maitenance action. If the area of erosion or peeling is more than 50%, the cone (front) segment must be replaced within 50 hours (AMM 72-31-01/401). c) FOR ENGINES WITH PN 51A681 AND 51A760; Erosion, peeling or flaking of the flouroelastomer coating on the cone (front) segment is not permitted except in the bolt pocket corners. Replace the cone (front) segment within 50 hours if there is any erosion, peeling or flaking of the flouroelastomer coating (AMM 72-31-01/401). Repair the flouroelastomer coating in bolt pocket corner if there is any erosion, peeling or flaking (AMM 72-31-01/801).
NOTE: This is a temporary repair and the part must be
____ replaced at the next scheduled maintenance interval.
d) For cone (rear) segment, erosion or peeling of the black protective paint is permitted up to 10% of the surface area, but the part must be replaced at the next scedulad maintenance action. If the area of erosion or peeling is more than 10% of the surface area the cone (rear) segment must be replaced within 50 hours (AMM 72-31-01/401).
3) Limits of the internal flange area for cracks that you can see are as follows: a) The damage that follows is permitted if it is in the areas with sufficient resin in the front and rear flanges.
NOTE: The front and rear flange cannot be readily
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