EFFECTIVITY
ALL CFM56 ENGINES
CFMI PROPRIETARY INFORMATION
CFM56-ALL
TRAINING MANUAL
COMBUSTION
CHAMBER
BORESCOPE
INSPECTION
Page 122
Sep 03
COMBUSTION SECTION
(-5B, -7B) :
Possible defects in the DAC dome area.
Whenever the combustion chamber is inspected, the
following defects should be assessed with the AMM
serviceability limits :
- Cracks, or tears.
- Erosion.
- Distortion of internal parts.
- Missing material.
- Dirt buildup.
- Burn-through holes.
- Flaking of Thermal Barrier Coating (TBC).
Possible defects on the DAC outer and inner liners.
Carbon deposits are often misinterpreted as defects
(holes, burn-through, cracks, etc.). Use the high
magnification probe, and higher light intensity to confirm
the type of defect.
The aft panel of the inner liner is susceptible to distortion
and cracking. The first evidence of this is a discoloration
in a round spot approximately the size of a large dilution
hole, which is followed by distortion and cracking. This
usually occurs uniformly around the liner.
TOC
