Borescope Inspection of the Booster Blades and Vanes (PRE SB 72-00-0080) [CFML]

TASK 72-21-00-290-802-A
Borescope Inspection of the Booster Blades and Vanes (PRE SB 72-00-0080)

WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE PARTS AFTER THE ENGINE SHUTDOWN. USE APPLICABLE THERMAL GLOVES. THE ENGINE PARTS CAN STAY HOT FOR ONE HOUR AFTER SHUTDOWN AND CAN BURN YOU.

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

WARNING: BEFORE YOU INSTALL/REMOVE THE GSE TOOL, READ THE MANUFACTURER'S INSTRUCTIONS, AND, WHILE YOU OPERATE THIS TOOL, CAREFULLY OBEY THEM. IF YOU DO NOT DO THIS, INJURY TO PERSONS AND DAMAGE TO EQUIPMENT CAN OCCUR.

ZONE: 210
ZONE: 400

1. Reason for the Job
This procedure gives the criteria for the borescope inspection of the Low Pressure Compressor (LPC) blades and vanes, except LPC Stage 1 vane.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 1M(3 FT)
No specific	1	BORESCOPE - FLEXIBLE
No specific	1	GROUND POWER UNIT - ELECTRICAL
No specific	AR	WARNING NOTICE(S)
No specific	Torque wrench: range to between 113 and 97 lbf.in (1.28 and 1.10 m.daN )
856A1320	1	BORESCOPE-KIT
856A1322	1	BORESCOPE-LIGHT SOURCE SET
956A7019G02	1	GUIDE, BORESCOPE INSPECTION - BOOSTER??

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.CP2619)	Never Seez-Pure Nickel, Special

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
210	CKPT,FWD COMPT BHD TO FLT COMPT BULKHEAD
400	POWER PLANT, NACELLES AND PYLONS
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL, 438AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL, 448AR

D. Referenced Information

REFERENCE	DESIGNATION
TASK 71-13-00-010-803-A	Opening of the Fan Cowl Doors
TASK 71-13-00-410-803-A	Closing of the Fan Cowl Doors
TASK 72-00-00-290-812-A	Engine Borescope Examination Preparation
TASK 72-21-00-300-802-A	Blend Repair of the Flow Splitter
Borescope Inspection of the Booster Blades and Vanes (PRE SB 72-00-0080)

3. Job Set-up
Subtask 72-21-00-941-092-A

A. Safety Precautions
(1) On the center pedestal, on ENG panel 115VU:
(a) Make sure that the ENG/MODE selector switch is in the NORM position.
(b) Make sure that the ENG/MASTER 1(2) control switch was in the OFF position not less than five minutes before you do this procedure.
(c) Put WARNING NOTICE(S) in position to tell persons not to operate:

The ENG/MODE selector switch
The ENG/MASTER 1(2) control switch.

(2) On the ENG section of maintenance panel 50VU:
(a) Make sure that the ON legend of the FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put a WARNING NOTICE(S) in position to tell persons not to energize FADEC 1(2).

Subtask 72-21-00-010-067-A

B. Get Access
(1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-803):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL 448AR
(2) Put an ACCESS PLATFORM 1M(3 FT) in position.

4. Procedure

CAUTION: TITANIUM PARTS REQUIRE THE USE OF NON-HALOGENATED SOLVENTS.

Subtask 72-21-00-210-065-A

A. Borescope Inspection of the Booster Blades and Vanes
(1) Location of the inspection holes and borescope view:
(a) Borescope ports A and B are located at the 3:30 o'clock position around the booster section.
1 You can see the borescope view of the stage 2 and 3 booster rotor blades (1) and the stage 4 booster rotor blades (1) Leading Edge (LE), through borescope ports A and B and the booster inlet.
2 You can see the borescope view of the stages 2 and 3 booster stator vanes (2) and the stage 4 booster stator vane (2) LE, next to borescope ports A and B.
(b) Borescope port E is located at 4:30 o'clock position around the High Pressure Compressor (HPC) section.
1 You can see the borescope view of the stage 4 booster rotor blade (1) Trailing Edge (TE) and the stage 4 booster stator vane (2) TE through the HPC borescope port E.
(2) Install the 956A7019G02 GUIDE, BORESCOPE INSPECTION - BOOSTER?? between the Outlet Guide Vanes (OGVs) No. 13 and No. 14, and with the borescope nozzles in the holes of the flowpath fairing.

NOTE: OGVs are numbered clockwise aft looking forward starting from OGV No. 1 which is the first OGV immediately after the strut No. 1.

(3) To inspect the stage 2 and 3 booster rotor blades (1) and the stage 4 booster rotor blade (1) LE:

CAUTION: MAKE SURE THAT THE INPUT VOLTAGE OF THE BORESCOPE LIGHT SOURCE SET CORRESPONDS TO THAT OF THE POWER SUPPLY.

CAUTION: MAKE SURE THAT : THE ON-OFF SWITCH IS IN THE OFF POSITION. THE LIGHT INTENSITY CONTROL IS SET TO THE MINIMUM BEFORE YOU CONNECT THE BOROSCOPE LIGHT-SOURCE SET TO THE POWER SUPPLY. MAKE SURE THAT THE LIGHT SOURCE AND THE POWER SUPPLY ARE CORRECTLY GROUNDED.

(a) Use a 856A1320 BORESCOPE-KIT with a long right angle extension.
(b) Use a 856A1322 BORESCOPE-LIGHT SOURCE SET.

NOTE: If the fan blades are removed, you can see the LE of the stage 2 booster rotor blades (1) without borescope equipment.

(c) Connect the 856A1322 BORESCOPE-LIGHT SOURCE SET to an GROUND POWER UNIT - ELECTRICAL.
(d) Connect the fiber light cable to the 856A1320 BORESCOPE-KIT and to the port on the 856A1322 BORESCOPE-LIGHT SOURCE SET.
(e) Turn the light source on.
(f) Engage the borescope and the long right-angle extension as necessary for the inspection.
(4) To examine the stage 2 and 3 booster stator vanes (2) and the stage 4 booster stator vane (2) LE:
(a) Use a BORESCOPE - FLEXIBLE with a videoprobe.
(b) Engage the fiberscope through the booster inlet and the inspection holes (Port A) and (Port B).
(5) To examine the stage 4 booster rotor blade (1) TE and the stage 4 stator vanes (2) TE:
(a) Use a BORESCOPE - FLEXIBLE with a videoprobe.
(b) Remove the compressor stator borescope plug (073S2) of the inspection hole (Port E) (Ref. AMM TASK 72-00-00-290-812).
(c) Insert through the HPC inspection hole (Port E).
(d) Engage the fiberscope through the HPC stage 2 rotor blade, HPC stage 1 stator vane and the intermediate housing until the stage 4 booster stator vane (2) TE and the stage 4 booster rotor blade (1) TE.

WARNING: BE CAREFUL WHEN YOU TURN THE FAN ROTOR MANUALLY. USE HEAVY PROTECTIVE GLOVES AND MAKE SURE THAT YOU CANNOT SLIP. IF YOU DO NOT OBEY THESE INSTRUCTIONS, INJURY CAN OCCUR.

(6) Do a borescope inspection of the booster rotor blades (1) all stages, when the fan rotor is turned clockwise, aft looking forward.

INSPECT / CHECK	MAXIMUM SERVICEABLE LIMITS	REMARKS	MAXIMUM REPAIRABLE LIMITS	REPAIR METHOD
1. Cracks and tears on the booster rotor blades (1).	Not serviceable.
2. Deposits on the booster rotor blades (1).	Any amount.
Criteria in the LE Area
3. Nicks, dents in Area A2 in the booster rotor blades (1).	Any number, if not more than 0.0118 in. (0.30 mm) in depth axially.	Protrusion is acceptable.
4. Scratches in Area A2 on the booster rotor blades (1).	Not serviceable.
5. Nicks, dents in Area B1 on the booster rotor blades (1).	Any number, if not more than 0.0118 in. (0.30 mm) in depth axially.	Protrusion is acceptable.	Up to five blades repaired, if under repairable limit.	Refer to (Ref. AMM TASK 72-21-00-300-802).
6. Scratches in Area B1 on the booster rotor blades (1).	Any number, if not more than 0.00098 in. (0.025 mm) in depth.		Up to five blades repaired, if under repairable limit.	Refer to (Ref. AMM TASK 72-21-00-300-802).
7. Nicks, dents in Area B2 on the booster rotor blades (1).	Any number, if not more than 0.0177 in. (0.45 mm) in depth axially.	Protrusion is acceptable.	Up to five blades repaired, if under repairable limit.	Refer to (Ref. AMM TASK 72-21-00-300-802).
8. Scratches in Area B2 on the booster rotor blades (1).	Any number, if not more than 0.00098 in. (0.025 mm) in depth.		Up to five blades repaired, if under repairable limit.	Refer to (Ref. AMM TASK 72-21-00-300-802).
9. Local distortions in Area A2 on the booster rotor blades (1).	Not serviceable.
10. Local distortions in Area B1 on the booster rotor blades (1).	Not serviceable.
11. Local distortions in Area B2 on the booster rotor blades (1).	Acceptable, if the maximum circumferential displacement is not more than 0.0197 in. (0.50 mm).
Criteria in the TE Area
12. Nicks, dents in Area A3 on the booster rotor blades (1).	Any number, if not more than 0.0118 in. (0.30 mm) in depth axially.	Protrusion is acceptable.
13. Scratches in Area A3 on the booster rotor blades (1).	Not serviceable.
14. Nicks, dents in Area B3 on the booster rotor blades (1).	Any number, if not more than 0.0236 in. (0.60 mm) in depth axially.	Protrusion is acceptable.	Up to five blades repaired, if under repairable limit.	Refer to (Ref. AMM TASK 72-21-00-300-802).
15. Scratches in Area B3 on the booster rotor blades (1).	Any number, if not more than 0.00098 in. (0.025 mm) in depth.		Up to five blades repaired, if under repairable limit.	Refer to (Ref. AMM TASK 72-21-00-300-802).
16. Nicks, dents in Area B4 on the booster rotor blades (1).	Any number, if not more than 0.0047 in. (0.12 mm) in depth axially.	Protrusion is acceptable.	Up to five blades repaired, if under repairable limit.	Refer to (Ref. AMM TASK 72-21-00-300-802).
17. Scratches in Area B4 on the booster rotor blades (1).	Any number, if not more than 0.00098 in. (0.025 mm) in depth.		Up to five blades repaired, if under repairable limit.	Refer to (Ref. AMM TASK 72-21-00-300-802).
18. Local distortions in Area A3 on the booster rotor blades (1).	Not serviceable.
19. Local distortions in Area B3 on the booster rotor blades (1).	Not serviceable.
20. Local distortions in Area B4 on the booster rotor blades (1).	Acceptable, if the maximum circumferential displacement is not more than 0.0197 in. (0.50 mm).
Criteria in the Convex and the Concave Side Areas (Outside the LE and the TE)
21. Nicks, dents in Area A1 on the booster rotor blades (1).	All quantities, if not more than 0.0236 in. (0.60 mm) diameter circle.	Protrusion is acceptable, if not through.
22. Scratches in Area A1 on the booster rotor blades (1).	Not serviceable.
23. Nicks, dents in Area C on the booster rotor blades (1).	All quantities not more than 0.0492 in. (1.25 mm) diameter circle.	Protrusion is acceptable, if not through.
24. Scratches in Area C on the booster rotor blades (1).	Any number, if not more than 0.0020 in. (0.05 mm) in depth.
25. Nicks, dents in Area D on the booster rotor blades (1).	Any number, if not more than 0.0098 in. (0.25 mm) in depth radially.	Protrusion is acceptable.
26. Scratches in Area D on the booster rotor blades (1).	Any number, if not more than 0.00098 in. (0.025 mm) in depth.
Criteria on the Blade Tip Corners
27. Missing pieces in the tip corners of booster rotor blades (1).	a. A maximum of ten blades are permitted with conditions given below: The axial length is less than 0.16 in. (4 mm). The radial length is less than 0.16 in. (4 mm). b. A maximum of three blades are permitted with conditions given below: The axial length is less than 0.24 in. (6 mm). The radial length is less than 0.24 in. (6 mm).
28. Wear or local distortions in tip corner on the LE or the TE of the booster rotor blades (1).	a. A maximum of ten blades are permitted with conditions given below: The axial length is less than 0.16 in. (4 mm). The radial length is less than 0.16 in. (4 mm). b. A maximum of three blades are permitted with conditions given below: The axial length is less than 0.24 in. (6 mm). The radial length is less than 0.24 in. (6 mm).

(7) When foreign object damage or missing pieces are found on the booster rotor blades (1), do a borescope inspection of booster stator vanes (2) stages 2, 3 and 4.

INSPECT / CHECK	MAXIMUM SERVICEABLE LIMITS	REMARKS	MAXIMUM REPAIRABLE LIMITS	REPAIR METHOD
1. Missing pieces of the booster stator vanes (2).	Not serviceable.
2. Broken vane of the booster stator vanes (2).	Not serviceable.
3. Cracks and tears in all areas of the booster stator vanes (2).	Not serviceable.
4. Vane looseness of the booster stator vanes (2).	Not serviceable.
5. Deposits on the booster stator vanes (2).	All quantities.
6. Erosion in the Areas B of the booster stator vanes (2).	Any amount.
Criteria in the LE Area
7. Nicks, dents in Area A on the LE of the booster stator vanes (2).	Any number, if not more than 0.0039 in. (0.10 mm) in depth axially.	Protrusion is acceptable, if not through.
8. Scratches in Areas A on the LE of the booster stator vanes (2).	Not serviceable.
9. Nicks, dents in Area B on the LE of the booster stator vanes (2).	All quantities, if not more than 0.0098 in. (0.25 mm) in depth axially.	Protrusion is acceptable, if not through.	Up to six airfoils repairable, if under repairable limits (stage 2 only).	Refer to (Ref. AMM TASK 72-21-00-300-802).
10. Scratches in Areas B LE of the booster stator vanes (2).	Any number, if not more than 0.0020 in. (0.05 mm) in depth.	No intersection permitted.	Up to six airfoils repairable, if under repairable limits (stage 2 only).	Refer to (Ref. AMM TASK 72-21-00-300-802).
11. Local distortion on the LE of the booster stator vanes (2).	Any number, if integrally outside Area F and it the length L along the LE (or TE) is not more than 0.2950 in. (7.5 mm) and the maximum dimension X along the circumferential direction is not more than 0.0295 in. (0.75 mm).
Criteria in the TE Area
12. Nicks, dents in Area A on the TE of the booster stator vanes (2).	All quantities, if not more than 0.0079 in. (0.20 mm) in depth axially.	Protrusion is acceptable, if not through.
13. Scratches in Areas A on the TE of the booster stator vanes (2).	Not serviceable.
14. Nicks, dents in Area B on the TE of the booster stator vanes (2).	All quantities, if not more than 0.0157 in. (0.40 mm) in depth axially.	Protrusion is acceptable, if not through.
15. Scratches in Area B TE of the booster stator vanes (2).	Any number, if not more than 0.0020 in. (0.05 mm) in depth.	No intersection permitted.
16. Local distortion on the TE of the booster stator vanes (2).	Any number, if integrally outside Area F and if length L along the LE (or TE) is not more than 0.2950 in. (7.5 mm) and the maximum dimension X along the circumferential direction is not more than 0.0295 in. (0.75 mm).
Criteria in the Convex and the Concave Side Areas (Outside the LE and the TE)
17. Nicks, dents in Area A on the booster stator vanes (2).	All quantities, if not more than 0.0236 in. (0.60 mm) in diameter circle.	Protrusion is acceptable, if not through.
18. Scratches in Areas A of the booster stator vanes (2).	Not serviceable.
19. Nicks, dents in Area E of the booster stator vanes (2).	All quantities, if not more than 0.0236 in. (0.60 mm) in diameter circle.	Protrusion is acceptable, if not through.
20. Scratches in Area E of the booster stator vanes (2).	Any number, if not more than 0.0020 in. (0.05 mm) in depth.	No intersection permitted.
21. Local distortion in Area E of the booster stator vanes (2).	Not serviceable.
Criteria on the Abradable Lining on the Outer Shroud
22. Erosion of the abradable lining on the outer shroud of the booster stator vanes (2).	All quantities.
23. Flaking of abradable lining on the outer shroud of the booster stator vanes (2).	The serviceable limit is 1.55 in.2 (1000 mm2) on each stage.	A continue- in-service limit of 100 hours is permitted, if the damage is more than the maximum serviceable limit on one of the stages.

(8) When the inspection is completed, do as follows:
(a) Turn the light source off.
(b) Make sure that the main-light-source blower is in the ON position until the lamp and the housing are cool.
(c) Remove the 856A1320 BORESCOPE-KIT from the engine.
(d) Remove the 956A7019G02 GUIDE, BORESCOPE INSPECTION - BOOSTER?? from the engine.

5. Close-up
Subtask 72-21-00-420-091-A

A. Installation of the Borescope Plug on the Port E (073S2)

CAUTION: WHEN YOU INSTALL THE BORESCOPE PLUGS, MAKE SURE THAT:

THE LOCKING FEATURE IS IN ONE OF THE TWO GROOVES ON THE BORESCOPE BOSS, AND
THERE IS NO GAP BETWEEN THE BORESCOPE BOSS AND PLUGS IN THE END.

IF YOU DO NOT OBEY THESE CONDITIONS, THE BORESCOPE PLUGS WILL NOT BE CORRECTLY INSTALLED.

(1) Apply CP2619Never Seez-Pure Nickel, Special to the threads of the borescope plugs and install on the HPC case.
(2) TORQUE the plug to between 113 and 97 lbf.in (1.28 and 1.10 m.daN )

Subtask 72-21-00-410-069-A

B. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-803):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL 448AR
(3) Remove the access platform(s).
(4) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 02:51:13 UTC