DOC AIRBUS | AMM A320FBorescope Inspection of the High-Pressure Turbine-Nozzle Assembly [CFMI]
TASK 72-51-00-290-002-A
Borescope Inspection of the High-Pressure Turbine-Nozzle Assembly
1. Reason for the Job
A. Fixtures, Tools, Test and Support Equipment
B. Consumable Materials
C. Work Zones and Access Panels
D. Referenced Information
3. Job Set-up
Subtask 72-51-00-941-050-A ** ON A/C NOT FOR ALL
Subtask 72-51-00-010-051-A ** ON A/C NOT FOR ALL
Subtask 72-51-00-410-050-A ** ON A/C NOT FOR ALL
[Rev.10 from 2021]
2026.04.01 02:39:29 UTC
Borescope Inspection of the High-Pressure Turbine-Nozzle Assembly
1. Reason for the Job
NOTE: Inspection of the high pressure turbine (HPT) nozzle assembly 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 position are located immediately in front of the fuel manifold. Special inspection of the HPT nozzle convex side can be accomplished, if required with a flexible borescope.
2. Job Set-up InformationA. Fixtures, Tools, Test and Support Equipment
| REFERENCE | QTY | DESIGNATION |
|---|---|---|
| No specific | AR | ACCESS PLATFORM 1M(3 FT) |
| 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 ) | |
| 856A1310 | 1 | KIT, BORESCOPE GUIDE - HP TURBINE |
| 856A1320 | 1 | BORESCOPE-KIT |
| 856A1321 | 1 | FIBERSCOPE SET |
| 856A1322 | 1 | BORESCOPE-LIGHT SOURCE SET |
| 856A1323 | 1 | MONITOR, RESOLUTION BORESCOPE |
| 856A1351 | 1 | GUIDE TUBE,BORESCOPE-HPT SHROUD |
| 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 |
Inspection of the High-Pressure Turbine-Nozzle AssemblySubtask 72-51-00-941-050-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 72-51-00-010-050-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. Get Access
(1) Open the fan cowl doors: (Ref. AMM TASK 71-13-00-010-040)
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(2) Put the ACCESS PLATFORM 1M(3 FT) in position.
Subtask 72-51-00-040-050-A ** ON A/C NOT FOR ALL Subtask 72-51-00-010-052-A ** ON A/C NOT FOR ALL (1) Open the fan cowl doors: (Ref. AMM TASK 71-13-00-010-040)
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(2) Put the ACCESS PLATFORM 1M(3 FT) in position.
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 72-51-00-010-051-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 72-51-00-290-050-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) Connect the fiber light cable to the 856A1320 BORESCOPE-KIT (856A1320 P04 or P05), and to the port on 856A1322 BORESCOPE-LIGHT SOURCE SET (856A1322 P02 or P03 or P04 or P07 or P08).
(3) Rotate and adjust the borescope to view the HPT nozzle area.
(4) If inspection of the nozzle convex side is necessary, use a 856A1321 FIBERSCOPE SET (856A1321 P01 or P03) and 856A1310 KIT, BORESCOPE GUIDE - HP TURBINE (856A1310G01), or 856A1351 GUIDE TUBE,BORESCOPE-HPT SHROUD (856A1351P01).
(6) When the inspection is complete, turn off the light source and remove the borescope and the guide tube.
(7) If any defects are found then remove additional borescope plugs and the spark igniters to inspect all of the HPT nozzle assembly.
(8) Remove the drain tube from the fuel nozzle adjacent to the 6 o'clock borescope plug S14.
(10) Remove the spark igniters.
(b) Install CAP - PROTECTION on the leads and the spark igniters.
(11) repeat steps (2) through (6) for each spark igniter location.
(12) Apply a small amount of graphite grease (Material No.CP2101) orCP2619 Never Seez-Pure Nickel, Special
(13) Install the borescope plugs:
.
(b) Wirelock the plugs withCP8001 lockwire 0.032 in. (0.8 mm) dia.
(14) If necessary install the fuel drain tube on the fuel nozzle adjacent to the 6 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.
(15) 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) Connect the fiber light cable to the 856A1320 BORESCOPE-KIT (856A1320 P04 or P05), and to the port on 856A1322 BORESCOPE-LIGHT SOURCE SET (856A1322 P02 or P03 or P04 or P07 or P08).
NOTE: Use the 856A1323 MONITOR, RESOLUTION BORESCOPE (856A1323G01) to make sure the borescope or the fiberscope and the light source are serviceable. See the Non-Destructive Test Manual for this procedure (Ref. NDTM 720000).
(2) Put the rigid borescope, of the 856A1320 BORESCOPE-KIT (856A1320/P04 or P05), into the ports and turn on the light source 856A1322 BORESCOPE-LIGHT SOURCE SET (856A1322/PO3 or PO4). (3) Rotate and adjust the borescope to view the HPT nozzle area.
(4) If inspection of the nozzle convex side is necessary, use a 856A1321 FIBERSCOPE SET (856A1321 P01 or P03) and 856A1310 KIT, BORESCOPE GUIDE - HP TURBINE (856A1310G01), or 856A1351 GUIDE TUBE,BORESCOPE-HPT SHROUD (856A1351P01).
NOTE: If 856A1310 KIT, BORESCOPE GUIDE - HP TURBINE is used to view the convex side, an 8 ft. (2.43 m) fiberscope must be used.
(5) Inspect the following: | INSPECT/CHECK | MAXIMUM SERVICEABLE LIMITS | REMARKS |
|---|---|---|
| 1.Leading edge of vane airfoil for: | | |
| A.Cracks | Any amount | |
| B.Burned or oxidized areas. | Any amount | |
| C.Missing material. | Any amount in radial direction (vane height). Any amount, provided missing material is not beyond row 11 holes (concave side direction) and not beyond row 2A holes or beyond row 2 if there is no row 2A (convex side direction). | See limit extension (Ref. AMM TASK 72-00-00-200-005). NOTE: When determining the airfoil's missing material, do not include the burn areas that surround the missing material. NOTE: Some configuration nozzles have no row 2A. |
| D.Baffle NOTE: The airfoil's baffle is visible inside the airfoil when missing material occurs. It is sheet metal with cooling holes. | | |
| (1) Cracks. | Any amount. | |
| (2) Missing material. | Any area equivalent to a rectangle defined by 4 adjacent holes. | See limit extension (Ref. AMM TASK 72-00-00-200-005). |
| 2.Concave surface of vane airfoil for: | | |
| A.Cracks. | Any number | |
| B.Burns | Any number ; no burn through. | See limit extension (Ref. AMM TASK 72-00-00-200-005). |
| 3.Convex surface of vane airfoil for: | | |
| A.Radial cracks. | Any number. | |
| B.Axial cracks. | Any number. | |
| C.Burns and bulges. | Any number. | |
| D.Missing panel | Not serviceable. | See limit extension (Ref. AMM TASK 72-00-00-200-005). |
| E.Missing thermal barrier coating (TBC) | Any amount. | |
| 4.Trailing edge of vane airfoil for: | | |
| A.Axial cracks starting from slots adjacent to trailing edge | Any number. | |
| B.Burns and cracks. | Any number. | |
| C.Buckling or bowing | Any amount. | |
| D.Missing material (loss of metal). | Total area removed from trailing edge not to be more than 0.5 in. (12.7 mm) in axial direction. | See limit extension (Ref. AMM TASK 72-00-00-200-005). |
| 5.All areas of airfoil for: | | |
| A.Craze cracking. | Any amount. NOTE: Craze cracking looks like many surface cracks that have no visual width or depth. | |
| B.Nicks, scores, scratches and dents. | Any number. | |
| C.Metal splatter. | Any amount. | |
| D.Missing codep coating. | Any amount. | |
| 6.Inner and outer platform for: | | |
| A.Cracks in parent metal. | Any number. | |
| B.Missing metal or burning of parent metal. | No through holes, but any amount of missing material from cracking or burning is permitted. | See limit extensions (Ref. AMM TASK 72-00-00-200-005). |
| C.Nicks, scores, scratches and dents or platform surface. | Any amount. | |
| D.Bulging and bowing. | Any amount. | |
| E.Cracks in platform braze joint. | Any amount, no separation of braze joint allowed unless caused by burning. | |
(7) If any defects are found then remove additional borescope plugs and the spark igniters to inspect all of the HPT nozzle assembly.
(8) Remove the drain tube from the fuel nozzle adjacent to the 6 o'clock borescope plug S14.
NOTE: If you remove the drain tube from the fuel nozzle adjacent to the 6 o'clock borescope plug, you must do a leak check after this inspection. Use the 6 o'clock borescope port only if necessary.
(9) Remove the borescope plugs from the approximate 1 and 6 o'clock positions. (10) Remove the spark igniters.
WARNING:
BEFORE YOU START WORK ON THE IGNITION SYSTEM, MAKE SURE THAT THE IGNITION EXCITERS ARE DE-ENERGIZED FOR A MINIMUM OF FIVE MINUTES. ALSO DO NOT TOUCH THE ELECTRICAL CONTACTS.
THE IGNITION SYSTEM VOLTAGE IS VERY HIGH, AND THE IGNITION EXCITERS CAN HAVE AN ELECTRICAL CHARGE EVEN WHEN NOT ENERGIZED. IF YOU DO NOT OBEY THESE PRECAUTIONS, INJURY CAN OCCUR.
CAUTION:
MAKE SURE THAT THE FIRST HINGE-TYPE CLAMP IS RELEASED BEFORE YOU REMOVE THE IGNITION LEAD FROM THE SPARK IGNITER. THIS WILL PREVENT DAMAGE TO THE CERAMIC TIP ON THE IGNITER END OF THE IGNITION LEAD.
(a) Remove the spark igniters (Ref. AMM TASK 74-21-30-000-001). (b) Install CAP - PROTECTION on the leads and the spark igniters.
(11) repeat steps (2) through (6) for each spark igniter location.
(12) Apply a small amount of graphite grease (Material No.CP2101) or
(13) 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) Wirelock the plugs with
(14) If necessary install the fuel drain tube on the fuel nozzle adjacent to the 6 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 (15) 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 72-51-00-410-050-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 72-51-00-440-050-A ** ON A/C NOT FOR ALL Subtask 72-51-00-410-051-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