DOC AIRBUS | AMM A320FBorescope Inspection of the Combustion Chamber Liners and Dome Area [CFMI]
TASK 72-42-00-290-001-A
Borescope Inspection of the Combustion Chamber Liners and Dome Area
1. Reason for the Job
Inspection of the combustion chamber is limited to the areas that can be seen with a rigid borescope, at the 1, 3, 6 and 10 o'clock borescope ports, and at the 2 spark igniter ports.
the borescope ports at the 1, 3, 6, and 10 o'clock positions are located immediately in front of the fuel manifold. These ports and the 2 spark igniter ports permit the borescope inspection of the combustion chamber and the HPT nozzle.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Consumable Materials
C. Work Zones and Access Panels
D. Referenced Information
3. Job Set-up
Subtask 72-42-00-941-050-A ** ON A/C NOT FOR ALL
Subtask 72-42-00-020-050-A ** ON A/C NOT FOR ALL
Subtask 72-42-00-410-050-A ** ON A/C NOT FOR ALL
[Rev.10 from 2021]
2026.04.01 12:58:53 UTC
Borescope Inspection of the Combustion Chamber Liners and Dome Area
1. Reason for the Job
Inspection of the combustion chamber is limited to the areas that can be seen with a rigid borescope, at the 1, 3, 6 and 10 o'clock borescope ports, and at the 2 spark igniter ports.
the borescope ports at the 1, 3, 6, and 10 o'clock positions are located immediately in front of the fuel manifold. These ports and the 2 spark igniter ports permit the borescope inspection of the combustion chamber and the HPT nozzle.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
| REFERENCE | QTY | DESIGNATION |
|---|---|---|
| No specific | AR | CAP - PROTECTION |
| No specific | AR | WARNING NOTICE(S) |
| No specific | Torque wrench: range to between 63 and 57 lbf.in (0.71 and 0.64 m.daN )  | |
| No specific | Torque wrench: range to between 135 and 120 lbf.in (1.53 and 1.36 m.daN ) | |
| 856A1320 | 1 | BORESCOPE-KIT |
| 856A1322 | 1 | BORESCOPE-LIGHT SOURCE SET |
| 856A1323 | 1 | MONITOR, RESOLUTION BORESCOPE |
| REFERENCE | DESIGNATION |
|---|---|
| (Material No.CP2101) | graphite grease |
| (Material No.CP2619) | Never Seez-Pure Nickel, Special |
| (Material No.CP8001) | lockwire 0.032 in. (0.8 mm) dia. |
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| FOR [1000EM1] (ENGINE-1) | |
| 437AL, 438AR, 451AL, 452AR | |
| FOR [1000EM2] (ENGINE-2) | |
| 447AL, 448AR, 461AL, 462AR | |
| REFERENCE | DESIGNATION |
|---|---|
| TASK 71-13-00-010-040-A | Opening of the Fan Cowl Doors |
| TASK 71-13-00-410-040-A | Closing of the Fan Cowl Doors |
| TASK 72-00-00-200-005-A | Over-Serviceable-Limit Extensions |
| TASK 73-11-40-790-001-A | Leak Check of the Fuel Nozzles |
| TASK 74-21-30-000-001-A | Removal of the Spark Igniter |
| TASK 74-21-30-400-001-A | Installation of the Spark Igniter |
| TASK 78-30-00-081-041-A | Make the Thrust Reverser Serviceable after Maintenance |
| TASK 78-30-00-481-041-A | Make the Thrust Reverser Unserviceable for Maintenance |
| TASK 78-36-00-010-040-A | Opening of the Thrust Reverser Doors |
| TASK 78-36-00-410-040-A | Closing of the Thrust Reverser Doors |
| NTM 720000 | |
Combustion Chamber (Inner and Outer Liner Inspection)Subtask 72-42-00-941-050-A ** ON A/C NOT FOR ALL
A. Safety Precautions
(1) On the center pedestal, on the ENG panel 115VU:
(a) Put a WARNING NOTICE(S) to tell persons not to start the engine.
(2) Make sure that the engine 1(2) shutdown occurred not less than 5 minutes before you do this procedure.
(3) On the overhead maintenance panel 50VU:
(a) Make sure that the ON legend of the ENG/FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put a WARNING NOTICE(S) to tell persons not to energize the FADEC 1(2).
Subtask 72-42-00-010-050-A ** ON A/C NOT FOR ALL (1) On the center pedestal, on the ENG panel 115VU:
(a) Put a WARNING NOTICE(S) to tell persons not to start the engine.
(2) Make sure that the engine 1(2) shutdown occurred not less than 5 minutes before you do this procedure.
(3) On the overhead maintenance panel 50VU:
(a) Make sure that the ON legend of the ENG/FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put a WARNING NOTICE(S) to tell persons not to energize the FADEC 1(2).
B. Open the fan cowl doors: (Ref. AMM TASK 71-13-00-010-040)
(1) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(2) FOR [1000EM2] (ENGINE-2)
447AL 448AR
Subtask 72-42-00-040-050-A ** ON A/C NOT FOR ALL Subtask 72-42-00-010-054-A ** ON A/C NOT FOR ALL (1) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(2) FOR [1000EM2] (ENGINE-2)
447AL 448AR
D. Open the thrust reverser doors: (Ref. AMM TASK 78-36-00-010-040)
(1) FOR [1000EM1] (ENGINE-1)
451AL 452AR
(2) FOR [1000EM2] (ENGINE-2)
461AL 462AR
4. Procedure(1) FOR [1000EM1] (ENGINE-1)
451AL 452AR
(2) FOR [1000EM2] (ENGINE-2)
461AL 462AR
Subtask 72-42-00-020-050-A ** ON A/C NOT FOR ALL
A. Remove parts before borescope inspection.
(1) Remove the borescope plugs from the approximate 3 and 10 o'clock positions on the combustion case.
Subtask 72-42-00-290-050-A ** ON A/C NOT FOR ALL (1) Remove the borescope plugs from the approximate 3 and 10 o'clock positions on the combustion case.
B. Do a borescope inspection
(1) Use the 856A1323 MONITOR, RESOLUTION BORESCOPE (856A1323G01) to make sure the borescope and the lightsource are serviceable. See the Non-Destructive Test Manual for this procedure. NTM 720000.
(2) Connect the fiber light cable to the 856A1320 BORESCOPE-KIT (856A1320P04/P05) and to the port on 856A1322 BORESCOPE-LIGHT SOURCE SET (856A1322P03/P04/P07).
(3) Put the rigid borescope, (856A1320P04/P05), into the ports and turn on the light source of the borescope-lightsource set (856A1322P03/P04).
(4) Turn the borescope to a full 360 degrees and adjust it so that you can see the dome of the combustion chamber, fuel nozzles, the inner and outer liners, and the aft sections.
(5) Inspect the following:
(6) When the inspection is complete, turn off the light source and remove the borescope.
(7) If any defects are found then remove additional borescope plugs and the spark igniters to inspect all of the combustion chamber.
If no defects are found, install parts removed for borescope inspection.
Subtask 72-42-00-010-053-A ** ON A/C NOT FOR ALL (1) Use the 856A1323 MONITOR, RESOLUTION BORESCOPE (856A1323G01) to make sure the borescope and the lightsource are serviceable. See the Non-Destructive Test Manual for this procedure. NTM 720000.
(2) Connect the fiber light cable to the 856A1320 BORESCOPE-KIT (856A1320P04/P05) and to the port on 856A1322 BORESCOPE-LIGHT SOURCE SET (856A1322P03/P04/P07).
(3) Put the rigid borescope, (856A1320P04/P05), into the ports and turn on the light source of the borescope-lightsource set (856A1322P03/P04).
(4) Turn the borescope to a full 360 degrees and adjust it so that you can see the dome of the combustion chamber, fuel nozzles, the inner and outer liners, and the aft sections.
(5) Inspect the following:
| INSPECT/CHECK | MAXIMUM SERVICEABLE LIMITS | REMARKS |
|---|---|---|
| 1.All surfaces for: | | |
| A.Discoloration | Any amount. | |
| B.Carbon Accumulation | Any amount. | |
| C.Missing, chipped or spalled areas of thermal barrier coating | Any amount | |
| 2.Dome Assembly (Spectacle Plate, Deflector and Sleeve) for: | | |
| A.Distortion of deflector or sleeve. | Any amount. | |
| B.Radial crack in spectacle plate. | Any number up to 2 in. (50.8 mm) length and not connected to each other. | See limit extension (Ref. AMM TASK 72-00-00-200-005). |
| C.Circumferential crack in spectacle plate. | Any number up to 3 in. (76.2 mm) length separated by 6 in. (152.4 mm). | See limit extension (Ref. AMM TASK 72-00-00-200-005). |
| D.Connected cracks in spectacle plate | Not more than (1) radial crack 2 in. (50.8 mm) long with (1) circumferential crack 3 in. (76.2 mm) long separated by 6 in. (152.4 mm) | See limit extension (Ref. AMM TASK 72-00-00-200-005). |
| E.Missing material from spectacle plate | Max. 0.06 in. (1.5 mm) x 0.06 in. (1.5 mm) at intersection of connected crack | See limit extension (Ref. AMM TASK 72-00-00-200-005). |
| F.Radial crack in deflector or sleeve. | Any number up to 0.5 in. (12.7 mm) length. | See limit extension (Ref. AMM TASK 72-00-00-200-005). |
| G.Circumferential cracks in deflector or sleeve. | Any number up to 0.75 in. (19 mm) length. | See limit extension (Ref. AMM TASK 72-00-00-200-005). |
| H.Connected cracks in deflector or sleeve. | Connection of any radial and circumferential cracks within limits of paragraphs F and G above. Limit is exceeded when third crack connects. | See limit extension (Ref. AMM TASK 72-00-00-200-005). |
| J.Missing material from extensions on deflector | Up to 9-exposed dome cooling holes permitted in each deflector quadrant (1-4) as shown in view XX, sheet 2 of the figure | See limit extensions, (Ref. AMM TASK 72-00-00-200-005) and view ZZ, sheet 2 of the figure |
| | More than 9-exposed dome cooling holes per quadrant are allowed if all exposed holes in the quadrant are within pattern restriction shown in view YY, sheet 2 of the figure | |
| K.Missing material from extensions on sleeve | Any amount up to 0.2 in (5.08 mm) maximum depth. | See limit extensions, (Ref. AMM TASK 72-00-00-200-005). |
| L.Burn through holes | 3 per dome 1 in. (25.4 mm) x 1 in. (25.4 mm) maximum. | See limit extension (Ref. AMM TASK 72-00-00-200-005). |
| M.Cracks in primary swirl nozzle | Any amount | |
| N.Fuel nozzles for dislodged wear sleeves | Not serviceable | See limit extension (Ref. AMM TASK 72-00-00-200-005). |
| 3.Inner and outer liners for: NOTE: Axial cracks can turn circumferential for a short distance (less than one dilution land in length). In this condition, you must think of the crack of as one continuous axial crack. | | |
| A.Outer liner axial cracks. | Any number across 1 panel or less and up to 4 cracks across more than 1 panel but not longer than 3 panels. | If a crack extends across more than 3 panels, borescope inspect the outer side of the outer liner in these locations. If the inspection reveals that the cracks do not extend through more than 1 of the 4, 5 and 6 ribs and rib 1 is not cracked through, reinspect the combustor in 750 cycles. 25 cycles maximum service extention allowed provided there are not more than 4 cracks across more than 1 panel, not to exceed 4 consecutive panels (no cooling rib inspection required). 25 cycles maximum service extention allowed provided not more than 4 cracks across more than 1 panel, not to exceed 5 panels and coupling rib 3, 4, 5 or 6 is not cracked through the outer side of the outer liner. NOTE: When applying limits, the dome band is interpreted as a panel. |
| B.Inner liner axial cracks. | Any number across 1 panel or less and up to 4 cracks across more than 1 panel but not longer than 2 panels. | If up to 1 crack is across 4 panels, and no material is missing more than 3 times the diameter of a dilution hole and does not connect to a circumferential crack longer than 0.5 in. (12.7 mm), then reinspect in 750 cycles. See limit extensions (Ref. AMM TASK 72-00-00-200-005). 25 cycles maximum service extention allowed, provided there are no more than 4 cracks across more than 1 panel, not to exceed 4 consecutive panels. |
| C.Circumferential cracks. | There is no limit to the number with these conditions: The cracks are no longer than 2 dilution lands. There are no more than 2 adjacent cracks in a dilution land. The cracks are separated by a minimum of 3 dilution lands that do not have cracks. | See limit extensions (Ref. AMM TASK 72-00-00-200-005). |
| D.Connected cracks. | Connection of any axial and circumferential cracks up to max limits of paragraphs A, B and C above. Limit is exceeded when third crack connects. Multiple axial and circumferential cracks that connect if cracks: a. Contained in one panel. b. Contained in one dilution land area. c. There are not more than two locations in the adjacent panels that are axially aligned. d. The locations are separated by a minimum of three dilution lands that do not have cracks. e. There are not more than five locations with connected cracks. | See limit extension (Ref. AMM TASK 72-00-00-200-005). |
| E.Burn through or missing material. | Per liner: any number of holes are permitted with these conditions:
| See limits extension (Ref. AMM TASK 72-00-00-200-005). |
| F.Missing overhangs. | Per liner: 14 areas each the size of a dilution hole providing maximum axial alignment of distress is 3 adjacent panels. | See limit extension (Ref. AMM TASK 72-00-00-200-005). |
| G.Distortion | Any amount within 0.5 in. (12.7 mm) of original contour. | See limit extension (Ref. AMM TASK 72-00-00-200-005). |
(7) If any defects are found then remove additional borescope plugs and the spark igniters to inspect all of the combustion chamber.
If no defects are found, install parts removed for borescope inspection.
C. Remove parts before borescope inspection.
(1) Remove the drain tube from the fuel nozzle adjacent to the 6 o'clock borescope plug.
(3) Remove both spark igniters (Ref. AMM TASK 74-21-30-000-001).
(4) Install CAP - PROTECTION on the leads and the spark igniters.
Subtask 72-42-00-290-052-A ** ON A/C NOT FOR ALL (1) Remove the drain tube from the fuel nozzle adjacent to the 6 o'clock borescope plug.
NOTE: If you remove the drain tube from the fuel nozzle adjacent to the 6 o'clock borescope plug, you will be required to perform a leak check after this inspection. Use the 6 o'clock borescope port only if necessary.
(2) Remove the borescope plugs from the approximate 1 and 6 o'clock positions. (3) Remove both spark igniters (Ref. AMM TASK 74-21-30-000-001).
(4) Install CAP - PROTECTION on the leads and the spark igniters.
D. Do a borescope inspection.
(1) Repeat the inspection procedure for each borescope and spark igniter location.
Subtask 72-42-00-420-050-A ** ON A/C NOT FOR ALL (1) Repeat the inspection procedure for each borescope and spark igniter location.
E. Install parts removed for borescope inspection.
(1) Apply a small amount of graphite grease (Material No.CP2101) orCP2619 Never Seez-Pure Nickel, Special
(2) Install the borescope plugs.
.
(b) Safety the plugs withCP8001 lockwire 0.032 in. (0.8 mm) dia.
(3) If necessary, install the fuel drain tube to the fuel nozzle adjacent to the six o'clock borescope plug. TORQUE the coupling nuts on the fuel drain tube to between 135 and 120 lbf.in (1.53 and 1.36 m.daN ) and safety with CP8001 lockwire 0.032 in. (0.8 mm) dia.
(4) If necessary, remove the protective caps and install the spark igniters (Ref. AMM TASK 74-21-30-400-001)
Subtask 72-42-00-790-050-A ** ON A/C NOT FOR ALL (1) Apply a small amount of graphite grease (Material No.CP2101) or
(2) Install the borescope plugs.
CAUTION:
BE SURE TO INSTALL THE CORRECT BORESCOPE PLUGS. THE COMBUSTOR BORESCOPE PLUGS DO NOT HAVE A STEM FEATURE. INADVERTENT INSTALLATION OF BORESCOPE PLUGS WITH STEMS FROM OTHER LOCATIONS WILL RESULT IN THE STEM FEATURE BEING BURNED AWAY BY COMBUSTION GASES.
(a) Install the borescope plugs and TORQUE to between 63 and 57 lbf.in (0.71 and 0.64 m.daN ) . (b) Safety the plugs with
(3) If necessary, install the fuel drain tube to the fuel nozzle adjacent to the six o'clock borescope plug. TORQUE the coupling nuts on the fuel drain tube to between 135 and 120 lbf.in (1.53 and 1.36 m.daN )
and safety with (4) If necessary, remove the protective caps and install the spark igniters (Ref. AMM TASK 74-21-30-400-001)
F. Do a fuel nozzle leak check.
(1) If you removed the drain tube from the fuel nozzle adjacent to the 6 o'clock borescope plug, do a fuel nozzle leak check (Ref. AMM TASK 73-11-40-790-001).
5. Close-up(1) If you removed the drain tube from the fuel nozzle adjacent to the 6 o'clock borescope plug, do a fuel nozzle leak check (Ref. AMM TASK 73-11-40-790-001).
Subtask 72-42-00-410-050-A ** ON A/C NOT FOR ALL
A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the thrust reverser doors: (Ref. AMM TASK 78-36-00-410-040)
(a) FOR [1000EM1] (ENGINE-1)
451AL 452AR
(b) FOR [1000EM2] (ENGINE-2)
461AL 462AR
Subtask 72-42-00-440-050-A ** ON A/C NOT FOR ALL Subtask 72-42-00-410-053-A ** ON A/C NOT FOR ALL (1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the thrust reverser doors: (Ref. AMM TASK 78-36-00-410-040)
(a) FOR [1000EM1] (ENGINE-1)
451AL 452AR
(b) FOR [1000EM2] (ENGINE-2)
461AL 462AR