Inspection of the Stage 1 Low-Pressure Turbine Nozzle Assembly [CFMI]

TASK 72-53-00-290-001-A
Inspection of the Stage 1 Low-Pressure Turbine Nozzle Assembly

FIN: 1000EM1 ** ON A/C NOT FOR ALL
FIN: 1000EM2 ** ON A/C NOT FOR ALL

1. Reason for the Job
Inspection of the low pressure turbine (LPT) nozzle is limited to the areas that can be seen with a rigid borescope. Insert the borescope through the borescope ports located on stage 1 LPT nozzle support. If no defects are found then the borescope inspection is complete. If defects are found then look at the high-pressure turbine (HPT) shrouds.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	ACCESS PLATFORM 1M(3 FT)
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 )
856A1320	1	BORESCOPE-KIT
856A1322	1	BORESCOPE-LIGHT SOURCE SET
856A1323	1	MONITOR, RESOLUTION BORESCOPE

B. Consumable Materials

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.

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
FOR [1000EM1] (ENGINE-1)
437AL, 438AR, 451AL, 452AR
FOR [1000EM2] (ENGINE-2)
447AL, 448AR, 461AL, 462AR

D. Referenced Information

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 72-53-00-290-002-A	Inspection of the High-Pressure Turbine Shroud
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
Borescope Inspection of the High-Pressure Turbine Shroud
Segment of the Stage 1 Low-Pressure Turbine Nozzle
Borescope Plugs Location

3. Job Set-up
Subtask 72-53-00-941-050-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 72-53-00-010-050-A ** ON A/C NOT FOR ALL

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 72-53-00-040-050-A ** ON A/C NOT FOR ALL

C. Make the thrust reverser unserviceable (Ref. AMM TASK 78-30-00-481-041).

Subtask 72-53-00-010-053-A ** ON A/C NOT FOR ALL

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
Subtask 72-53-00-020-050-A ** ON A/C NOT FOR ALL

A. Remove the S17 and S18 borescope plugs found ajacent to the aft flange of the combustion case at approximately the 5:30 and 8:30 o'clock positions (aft looking forward).

Subtask 72-53-00-290-050-A ** ON A/C NOT FOR ALL

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 P03 or P04 or P07).

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. NTM 720000.

(2) Put the borescope into the port. Turn on the light source.
(3) Inspect the low-pressure turbine nozzle as follows:

INSPECT/CHECK	MAXIMUM SERVICEABLE LIMITS	REMARKS
1.Stage 1 LPT nozzle for:
A.Cracks in leading edge.	Any number, that are not more than 0.6 in. (15.24 mm) long.	See limit extensions (Ref. AMM TASK 72-00-00-200-005).
B.Cracks in trailing edge.	Any number, that are not more than 0.8 in. (20.32 mm) long.	See limit extensions (Ref. AMM TASK 72-00-00-200-005).
C.Axial cracks on concave/convex side between inner and outer platform.	Any number, that are not more than 0.7 in. (17.80 mm) long if there is a separation of 0.25 in. (6.35 mm) between adjacent cracks.	See limit extensions (Ref. AMM TASK 72-00-00-200-005).
D.Radial cracks on convex side	One crack of 1 in. (25,4 mm) long if no axial crack on the same side of the airfoil.	See limit extensions (Ref. AMM TASK 72-00-00-200-005).
E.Burns, erosion and corrosion	Any amount, not through. Missing metal not to exceed accumulated area of 0.5 in.2 (322.60 mm2) per airfoil.	See limit extensions (Ref. AMM TASK 72-00-00-200-005).
F.Nicks, scores, scratches, dents or deposits on concave/convex surface or trailing edge	Any amount, not through, provided there are no cracks out of distressed area.	See limit extensions (Ref. AMM TASK 72-00-00-200-005).
G.Nicks, dents, tears or missing pieces in leading edge.	Any amount, provided there are no cracks out of distressed areas and missing metal does not exceed 0.5 in.2 (322.60 mm2) per vane segment.	See limit extensions (Ref. AMM TASK 72-00-00-200-005).
H.Cracks in inner or outer platform.	2 per segment up to 0.5 in. (12.70 mm) long provided no metal protrudes into air stream.	See limit extensions (Ref. AMM TASK 72-00-00-200-005).
J.Craze cracking	Any amount

NOTE: Craze cracking is defined as numerous superficial surface cracks which have no visual width or depth.

(4) If defects are found, Look at the HPT shrouds (Ref. AMM TASK 72-53-00-290-002).

Subtask 72-53-00-080-050-A ** ON A/C NOT FOR ALL

C. When the inspection is complete, turn off the light source 856A1322 BORESCOPE-LIGHT SOURCE SET (856A1322 P03, P04 or P07), and remove the rigid borescope 856A1320 BORESCOPE-KIT (856A1320 P04 or P05).

Subtask 72-53-00-420-050-A ** ON A/C NOT FOR ALL

D. Apply a small amount of graphite grease (Material No.CP2101) or CP2619Never Seez-Pure Nickel, Special to the borescope plug threads and pressure faces.
(1) Install the borescope plugs and TORQUE to between 63 and 57 lbf.in (0.71 and 0.64 m.daN )

.
(2) Wirelock the plugs with CP8001lockwire 0.032 in. (0.8 mm) dia..

5. Close-up
Subtask 72-53-00-410-050-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)
(3) FOR [1000EM1] (ENGINE-1)
451AL 452AR
(4) FOR [1000EM2] (ENGINE-2)
461AL 462AR

Subtask 72-53-00-440-050-A ** ON A/C NOT FOR ALL

B. Make the thrust reverser serviceable (Ref. AMM TASK 78-30-00-081-041)

Subtask 72-53-00-410-053-A ** ON A/C NOT FOR ALL

C. Close Access
(1) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-040):
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(2) Remove the access platform(s).
(3) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 13:04:44 UTC