Borescope Inspection of the Low Pressure Turbine (LPT) Assembly [PW11]

TASK 72-53-00-200-801-A
Borescope Inspection of the Low Pressure Turbine (LPT) Assembly

WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE AND THE ADJACENT COMPONENTS AFTER ENGINE SHUTDOWN. THE ENGINE, THE ENGINE OIL AND THE ADJACENT COMPONENTS CAN STAY HOT FOR A LONG TIME. IF YOU DO NOT OBEY THIS INSTRUCTION, INJURY CAN OCCUR.

WARNING: DO THE BORESCOPE INSPECTION IN AN AREA WHICH HAS PROTECTION FROM THE WEATHER. IF A BORESCOPE INSPECTION IS DONE IN WET CONDITIONS, USE SUFFICIENT PROTECTION TO PREVENT POSSIBLE ELECTRICAL SHOCK TO THE OPERATOR OR DAMAGE TO THE EQUIPMENT. AN ELECTRICAL SHOCK CAN KILL A PERSON OR CAUSE A BAD INJURY.

WARNING: USE PROTECTIVE GLOVES TO PREVENT POSSIBLE INJURY TO THE HANDS WHEN YOU TOUCH OR HOLD THE FAN BLADES. THE BLADE EDGES ARE SHARP AND CAN CUT THE HANDS.

CAUTION: DO NOT DO THIS PROCEDURE DURING WINDY CONDITIONS. THE WIND CAN ROTATE THE FAN AND CAUSE DAMAGE TO THE LPT ROTOR BLADES AND VANES AND TO THE BORESCOPE EQUIPMENT.

CAUTION: BE VERY CAREFUL WHEN YOU DO THE ROTATION OF THE FAN BLADES. THERE IS A GEAR RATIO OF APPROXIMATELY 1:3 BETWEEN THE FAN AND THE LPT ROTOR.

CAUTION: MAKE SURE THAT THE TEMPERATURE IN THE ENGINE IS LESS THAN 140 DEG.F (60 DEG.C) BEFORE YOU DO THE BORESCOPE INSPECTION. YOU CAN DO THIS INSPECTION ONLY WHEN YOU CAN EASILY TOUCH THE CASE ADJACENT TO THE BORESCOPE PORT. DAMAGE CAN OCCUR TO THE BORESCOPE EQUIPMENT IF THE GASPATH OR METAL TEMPERATURE IS MORE THAN 140 DEG.F (60 DEG.C).

ZONE: 400

1. Reason for the Job
Use this procedure to examine the Low Pressure Turbine (LPT) for damage to accessible LPT 2nd and 3rd stage vanes and all accessible areas of all LPT 1st, 2nd and 3rd stage blades as described in detail below.

NOTE: The visual inspection of the LPT 2nd and 3rd stage vanes is not mandatory however, the limits are provided in the event that damage is seen upon inserting the borescope through AP LPT-1 and AP LPT-2 access ports. This is only applicable to vanes that are immediately visible and accessible at the access ports. See Table 604 for the LPT 2nd stage vane limits and Table 605 for the LPT 3rd stage vane limits. Ref. Fig. 602/TASK 72-53-00-991-30800-001 for the LPT 2nd stage vanes and the LPT 3rd stage vanes.

Remove the AP-TIC access plug from the Turbine Intermediate Case (TIC) and AP-LPT-1 and AP-LPT-2 access plugs from the LPT case. Refer to the PW1100G-JM (Series) Engine Shop Manual, PN 5316992 or the PW1400G-JM (Series) Engine Shop PN 5321240, Engine General (Ref. TASK 72-00-00-000-80400).
The stages and quantities in the LPT from front to rear are as follows:
LPT 1st stage blades: 84
LPT 2nd stage vane assemblies: 60 airfoils (20 vane assemblies)
LPT 2nd stage blades: 86
LPT 3rd stage vane assemblies: 66 airfoils (11 vane assemblies)
LPT 3rd stage blades: 78

NOTE: The borescope inspection of all blade stages is for a full 360 degrees revolution minimum.

If there are unusual requirements that are not called out in the Standard Practice Manual, PN 585005 recommendations and requirements, the requirements will be given in the Support Equipment table and the Consumables, Materials and Expendables table. If there are no requirements (tables will not be shown), the Standard Practices Manual, PN 585005 recommendations and requirements will be followed.
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	THERMOMETER - METAL PROBE TYPE, 0 TO 400 DEG.F
CTE8003	1	SYSTEM BOROSCOPE (VIDEO)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
400	POWER PLANT, NACELLES AND PYLONS
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL, 438AR, 451AL, 452AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR, 461AL, 462AR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 71-00-00-860-817-A	Motor the Engine (Dry Method)
TASK 71-00-00-860-833-A	Procedure to Prevent Engine Motoring
TASK 71-13-00-010-802-A	Opening of the Fan Cowl Doors
TASK 71-13-00-410-802-A	Closing of the Fan Cowl Doors
TASK 72-00-00-000-804-A	Removal of the Borescope Plugs
TASK 72-00-00-400-804-A	Installation of the Borescope Plugs
TASK 78-30-00-040-805-A	Deactivation of the Thrust Reverser System for Ground Maintenance
TASK 78-30-00-440-805-A	Reactivation of the Thrust Reverser System after Ground Maintenance
TASK 78-36-00-010-802-A	Opening of the Thrust Reverser Cowl-Doors
TASK 78-36-00-410-802-A	Closing of the Thrust Reverser Cowl-Doors
Borescope Ports Location
Borescope inspection of the Low Pressure Turbine (LPT) Assembly

3. Job Set-up
Subtask 72-53-00-941-057-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) Do the procedure to prevent engine motoring
(Ref. AMM TASK 71-00-00-860-833).

Subtask 72-53-00-010-064-A ** ON A/C NOT FOR ALL

B. Get Access
(1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL, 438AR.
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR.
(2) Put the ACCESS PLATFORM 1M(3 FT) in position.

Subtask 72-53-00-040-056-A ** ON A/C NOT FOR ALL

C. Deactivation of the Thrust Reverser System for Ground Maintenance

WARNING: YOU MUST DEACTIVATE THE THRUST REVERSER BEFORE YOU DO WORK ON OR AROUND IT. IF YOU DO NOT, THE THRUST REVERSER CAN OPERATE ACCIDENTALLY AND CAUSE AN INJURY AND/OR DAMAGE.

(1) Do the deactivation of the thrust reverser system for ground maintenance (Ref. AMM TASK 78-30-00-040-805).

Subtask 72-53-00-010-065-A ** ON A/C NOT FOR ALL

D. Get Access
(1) Open the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-010-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
451AL, 452AR.
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
461AL, 462AR.

4. Procedure

CAUTION: WIPE CLEAN ALL PARTS AND TOOLS AS NECESSARY TO REMOVE UNWANTED DEBRIS AND PREVENT DAMAGE TO THE ENGINE.

Subtask 72-53-00-720-050-A ** ON A/C NOT FOR ALL

A. Borescope Inspection of the LPT Assembly
(1) If the engine has been run recently, check the temperature in the engine with the THERMOMETER - METAL PROBE TYPE, 0 TO 400 DEG.F.
(a) It is recommended that you wait three to five hours after engine shutdown before you do a borescope inspection.
(b) As an option, you can dry-motor the engine with the starter to decrease the engine core temperature (Ref. AMM TASK 71-00-00-860-817).
(2) Remove the Access Port (AP) TIC 1 borescope plug from the TIC, AP LPT-1 and AP LPT-2 borescope plugs from the LPT case at the 2:30 o'clock position (Ref. AMM TASK 72-00-00-000-804).

Borescope Ports Location ** ON A/C NOT FOR ALL

(3) Do a visual inspection of the accessible areas of all 1st, 2nd and 3rd stage LPT blades during the borescope inspection for prior blend repairs. It is possible to see an area that is worn more than the permitted damage limits because of a prior blend repair. You must examine this area very carefully to determine if this area is a new defect or an area that was blend repaired before.

Borescope inspection of the Low Pressure Turbine (LPT) Assembly ** ON A/C NOT FOR ALL

NOTE: The visual inspection of the 2nd and 3rd stage vanes is not mandatory however, the limits are provided in the event that damage is seen when the borescope is put through AP LPT-1 and AP LPT-2 access ports. This is only applicable to vanes that are immediately visible and accessible at the access ports.

(4) Turning of the fan clockwise:

CAUTION: DO NOT USE THE 3RD STAGE LPT BLADES TO TURN THE LPT ROTOR. ONLY USE THE FAN BLADES. IF YOU DO NOT OBEY THIS PRECAUTION, YOU CAN CAUSE DAMAGE TO THE LPT BLADES.

(a) Turn the fan clockwise to turn the LPT assembly counterclockwise (as seen from the rear) during the inspection.

NOTE: Turn the fan clockwise as seen from the rear (normal operation). If the fan is accidentally turned counterclockwise, there can be some resistance. This condition is permitted, but do not continue to turn the fan in the counterclockwise (incorrect) direction.

(5) Inspection performing:

WARNING: BE CAREFUL TO EXAMINE THE POWER CABLE OF THE LIGHT SOURCE BEFORE YOU USE IT. DO NOT USE THE CABLE IF THE INSULATION HAS CUTS OR WORN OR BROKEN AREAS. INSULATION WITH THIS TYPE OF DAMAGE IS DANGEROUS BECAUSE OF POSSIBLE ELECTRICAL SHOCK TO THE OPERATOR.

CAUTION: INSTALL PROTECTION COVERS ON ALL THE OPENINGS IMMEDIATELY TO PREVENT DAMAGE TO THE ENGINE.

CAUTION: DO NOT USE THE 3RD STAGE LPT BLADES TO TURN THE LPT ROTOR. ONLY USE THE FAN BLADES. IF YOU DO NOT OBEY THIS PRECAUTION, YOU CAN CAUSE DAMAGE TO THE LPT BLADES.

(a) Do the inspection with the CTE8003 SYSTEM BOROSCOPE (VIDEO).

NOTE: As an option, a flexible borescope can be used for all steps.

(6) The temperature in the engine must be less than 140 deg.F (60.00 deg.C) before you install a borescope in the engine.
(7) Have a second person slowly rotate the fan blades. There is no equipment to rotate the LPT rotor assembly.
(8) Borescope inspection:

CAUTION: MAKE SURE THAT ALL BLADE STAGES ARE INSPECTED FOR ONE COMPLETE 360° REVOLUTION MINIMUM. IF YOU DO NOT OBEY THIS INSTRUCTION, THERE IS A RISK THAT YOU WILL NOT SEE ALL THE SIGNS OF DAMAGE.

CAUTION: EXAMINE ONLY THE STAGE 2 AND 3 LPT VANES THAT YOU CAN GET ACCESS TO AND ALL THE BLADE STAGES AS GIVEN IN THE PROCEDURE. IF YOU FIND DAMAGE THAT IS MORE THAN THE PERMITTED LIMITS GIVEN IN THE TABLES, REMOVE THE ENGINE FROM SERVICE BEFORE THE END OF THE NEXT FIVE FLIGHT CYCLES. IF YOU DO NOT OBEY THIS CAUTION, DAMAGE TO THE EQUIPMENT CAN OCCUR.

(a) Do the borescope inspection of the 1st, 2nd and 3rd stage LPT blades and the 2nd and 3rd stage LPT vanes as follows:

NOTE: It is necessary to count the blades and vanes of the LPT because of the gear ratio Fan: LPT (approximately 1:3). One full fan rotation equals about three full LPT rotor rotations.

1 Install the borescope through the TIC access port for the visual inspection of all 1st stage LPT blade leading edges and visible airfoil areas.

Borescope inspection of the Low Pressure Turbine (LPT) Assembly ** ON A/C NOT FOR ALL

2 Do the borescope inspection of all 1st stage LPT blade leading edges and visible airfoil areas. Have a second person slowly turn the LPT rotor while you inspect the LPT 1st stage blades. The LPT rotor must be turned 360 degrees (one revolution) minimum to inspect all the LPT 1st stage blades. There are 84 1st stage LPT blades.
3 For this borescope inspection procedure, the permitted damage limits for the 1st stage LPT blades are shown in Table 601:

Borescope inspection of the Low Pressure Turbine (LPT) Assembly ** ON A/C NOT FOR ALL

a LPT 1st stage blade may exhibit surface defects which are permitted per production standards. Surface defects are not caused by hit of some objects or service operation and shall be evaluated like penetrant inspection indications. The acceptance limits per fluorescent penetrant inspection (Engine Series CIR Manual, PW1000G-C-72-53-3121-00A-351A-C) shall apply.
b If it is unclear whether a surface defect is due to the production process or to engine operation, contact Pratt & Whitney for disposition.
4 Install the borescope through the AP LPT-1 access port for the visual inspection of all 1st stage LPT blade trailing edges, visible airfoil areas, all 2nd stage LPT blade leading edges, visible airfoil areas and the 2nd stage LPT vane areas that are accessible.

Borescope inspection of the Low Pressure Turbine (LPT) Assembly ** ON A/C NOT FOR ALL

5 For this borescope inspection procedure, the permitted damage limits for the 2nd stage LPT vanes are shown in Table 604.

Borescope inspection of the Low Pressure Turbine (LPT) Assembly ** ON A/C NOT FOR ALL

6 Do the borescope inspection of all 1st stage LPT blade trailing edges and visible airfoil areas. Have a second person slowly turn the LPT rotor while you inspect the LPT 1st stage blades. The LPT rotor must be turned 360 degrees (one revolution) minimum to inspect all the LPT 1st stage blades. There are 84 1st stage LPT blades.
7 For this borescope inspection procedure, the permitted damage limits for the 1st stage LPT blades are shown in Table 601:

Borescope inspection of the Low Pressure Turbine (LPT) Assembly ** ON A/C NOT FOR ALL

a LPT 1st stage blade may exhibit surface defects which are permitted per production standards. Surface defects are not caused by hit of some objects or service operation and shall be evaluated like penetrant inspection indications. The acceptance limits per fluorescent penetrant inspection (Engine Series CIR Manual, PW1000G-C-72-53-3121-00A-351A-C) shall apply.
b If it is unclear whether a surface defect is due to the production process or to engine operation, contact Pratt & Whitney for disposition.
8 Do the borescope inspection of all 2nd stage LPT blade leading edges and visible airfoil areas. Have a second person slowly turn the LPT rotor while you inspect the LPT 2nd stage blades. The LPT rotor must be turned 360 degrees (one revolution) minimum to inspect all the LPT 2nd stage blades. There are 86 2nd stage LPT blades.
9 For this borescope inspection procedure, the permitted damage limits for the 2nd stage LPT blades are shown in Table 602:

Borescope inspection of the Low Pressure Turbine (LPT) Assembly ** ON A/C NOT FOR ALL

a LPT 2nd stage blade may exhibit surface defects which are permitted per production standards. Surface defects are not caused by hit of some objects or service operation and shall be evaluated like penetrant inspection indications. The acceptance limits per fluorescent penetrant inspection (Engine Series CIR Manual, PW1000G-C-72-53-3121-00A-351A-C) shall apply.
b If it is unclear whether a surface defect is due to the production process or to engine operation, contact Pratt & Whitney for disposition.
10 Install the borescope through the AP LPT-2 access port for the visual inspection of all 2nd stage LPT blade trailing edges, all 3rd stage LPT blade leading edges and the 3rd stage LPT vane areas that are accessible.

Borescope inspection of the Low Pressure Turbine (LPT) Assembly ** ON A/C NOT FOR ALL

11 For this borescope inspection procedure, the permitted damage limits for the 3rd stage LPT vanes are shown in Table 605.

Borescope inspection of the Low Pressure Turbine (LPT) Assembly ** ON A/C NOT FOR ALL

12 Do the borescope inspection of all 2nd stage LPT blade trailing edges and visible airfoil areas. Have a second person slowly turn the LPT rotor while you inspect the LPT 2nd stage blades. The LPT rotor must be turned 360 degrees (one revolution) minimum to inspect all the LPT 2nd stage blades. There are 86 2nd stage LPT blades.
13 For this borescope inspection procedure, the permitted damage limits for the 2nd stage LPT blade trailing edges are shown in Table 602:

Borescope inspection of the Low Pressure Turbine (LPT) Assembly ** ON A/C NOT FOR ALL

a LPT 2nd stage blade may exhibit surface defects which are permitted per production standards. Surface defects are not caused by hit of some objects or service operation and shall be evaluated like penetrant inspection indications. The acceptance limits per fluorescent penetrant inspection (Engine Series CIR Manual, PW1000G-C-72-53-3121-00A-351A-C) shall apply.
b If it is unclear whether a surface defect is due to the production process or to engine operation, contact Pratt & Whitney for disposition.
14 Do the borescope inspection of all 3rd stage LPT blade leading edges and visible airfoil areas. Have a second person slowly turn the LPT rotor while you inspect the LPT 3rd stage blades. The LPT must be turned 360 degrees (one revolution) minimum to inspect all the LPT 3rd stage blades. There are 78 3rd stage LPT blades.
15 For this borescope inspection procedure, the permitted damage limits for the 3rd stage LPT blades are shown in Table 603.

Borescope inspection of the Low Pressure Turbine (LPT) Assembly ** ON A/C NOT FOR ALL

16 Install the borescope through the Turbine Exhaust Case (TEC) for the visual inspection of all 3rd stage LPT blade trailing edges.

Borescope inspection of the Low Pressure Turbine (LPT) Assembly ** ON A/C NOT FOR ALL

17 Do the borescope inspection of all 3rd stage LPT blade trailing edges and visible airfoil areas. Have a second person slowly turn the LPT rotor while you inspect the LPT 3rd stage blades. The LPT rotor must be turned 360 degrees (one revolution) minimum to inspect all the LPT 3rd stage blades. There are 78 3rd stage LPT blades.
18 For this borescope inspection procedure, the permitted damage limits for the 3rd stage LPT blades are shown in Table 603.

Borescope inspection of the Low Pressure Turbine (LPT) Assembly ** ON A/C NOT FOR ALL

(b) Table 601: 1st Stage LPT Blade Borescope Inspection Limits

EXAMINE	DAMAGE	DISPOSITION
All visible areas of 1st stage LPT blades for:
Cracks	All quantities	Not permitted. Contact P&W.
Discoloration	Localized hot spots	Not permitted. Contact P&W.
Areas A and B (fillet radii all around) for:
Dents and nicks	All quantities	Not permitted. Contact P&W.
Pits	All quantities more than 0.002 in. (0.051 mm) diameter and more than 0.001 in. (0.025 mm) depth	Not permitted. Contact P&W.
Area C (airfoil leading and trailing edges) for:
Round bottom dents	All quantities more than 0.002 in. (0.051 mm) depth	Not permitted. Contact P&W.
Nicks	All quantities more than 0.001 in. (0.025 mm) depth	Not permitted. Contact P&W.
Pits	All quantities more than 0.002 in. (0.051 mm) diameter and more than 0.001 in. (0.025 mm) depth	Not permitted. Contact P&W.
Area D (airfoil leading edges) for:
Round bottom dents	All quantities up to 0.002 in. (0.051 mm) depth	Permitted.
	All quantities more than 0.002 in. (0.051 mm) depth and up to 0.004 in. (0.102 mm) depth if smallest dimension of defect is at least 18.8 times its depth	Permitted.
	All quantities more than 0.002 in. (0.051 mm) depth and up to 0.004 in. (0.102 mm) depth if smallest dimension of defect is less than 18.8 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.004 in. (0.102 mm) depth	Not permitted. Contact P&W.
Nicks and pits	All quantities up to 0.001 in. (0.025 mm) depth	Permitted.
	All quantities more than 0.001 in. (0.025 mm) depth and up to 0.004 in. (0.102 mm) depth if smallest dimension of defect is at least 18.8 times its depth	Permitted.
	All quantities more than 0.001 in. (0.025 mm) depth and up to 0.004 in. (0.102 mm) depth if smallest dimension of defect is less than 18.8 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.004 in. (0.102 mm) depth	Not permitted. Contact P&W.
Area E (airfoil) for:
Round bottom dents	All quantities more than 0.004 in. (0.102 mm) depth	Not permitted. Contact P&W.
Nicks	All quantities more than 0.002 in. (0.051 mm) depth	Not permitted. Contact P&W.
Pits	All quantities more than 0.002 in. (0.051 mm) diameter and more than 0.001 in. (0.025 mm) depth	Not permitted. Contact P&W.
Area F (outer shroud flow-path surfaces) for:
Round bottom dents	All quantities more than 0.002 in. (0.051 mm) depth	Not permitted. Contact P&W.
Nicks	All quantities	Not permitted. Contact P&W.
Area G (inner shroud flow-path surfaces (Area H not included)) for:
Round bottom dents	All quantities more than 0.001 in. (0.025 mm) depth	Not permitted. Contact P&W.
Nicks	All quantities more than 0.005 in. (0.127 mm) depth	Not permitted. Contact P&W.
Area H for:
LPT 2nd stage vane contact rub-in	All quantities more than 0.020 in. (0.508 mm) depth	Not permitted. Contact P&W.
Round bottom dents	All quantities more than 0.010 in. (0.254 mm) depth	Not permitted. Contact P&W.
Nicks and pits	All quantities more than 0.005 in. (0.127 mm) depth	Not permitted. Contact P&W.
Area J (airfoil trailing edge) for:
Round bottom dents	All quantities up to 0.002 in. (0.051 mm) depth	Permitted.
	All quantities more than 0.002 in. (0.051 mm) depth and up to 0.008 in. (0.203 mm) depth if smallest dimension of defect is at least 5.3 times its depth	Permitted.
	All quantities more than 0.002 in. (0.051 mm) depth and up to 0.008 in. (0.203 mm) depth if smallest dimension of defect is less than 5.3 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.008 in. (0.203 mm) depth	Not permitted. Contact P&W.
Nicks and pits	All quantities up to 0.001 in. (0.025 mm) depth	Permitted.
	All quantities more than 0.001 in. (0.025 mm) depth and up to 0.008 in. (0.203 mm) depth if smallest dimension of defect is at least 5.3 times its depth	Permitted.
	All quantities more than 0.001 in. (0.025 mm) depth and up to 0.008 in. (0.203 mm) depth if smallest dimension of defect is less than 5.3 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.008 in. (0.203 mm) depth	Not permitted. Contact P&W.

Area K (airfoil trailing edge) for:
Round bottom dents	All quantities up to 0.002 in. (0.051 mm) depth	Permitted.
	All quantities more than 0.002 in. (0.051 mm) depth and up to 0.004 in. (0.102 mm) depth if smallest dimension of defect is at least 5.3 times its depth	Permitted.
	All quantities more than 0.002 in. (0.051 mm) depth and up to 0.004 in. (0.102 mm) depth if smallest dimension of defect is less than 5.3 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.004 in. (0.102 mm) depth	Not permitted. Contact P&W.
Nicks and pits	All quantities up to 0.001 in. (0.025 mm) depth	Permitted.
	All quantities more than 0.001 in. (0.025 mm) depth and up to 0.004 in. (0.102 mm) depth if smallest dimension of defect is at least 5.3 times its depth	Permitted.
	All quantities more than 0.001 in. (0.025 mm) depth and up to 0.004 in. (0.102 mm) depth if smallest dimension of defect is less than 5.3 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.004 in. (0.102 mm) depth	Not permitted. Contact P&W.
Area L (airfoil trailing edge) for:
Round bottom dents	All quantities up to 0.002 in. (0.051 mm) depth	Permitted.
	All quantities more than 0.002 in. (0.051 mm) depth and up to 0.008 in. (0.203 mm) depth if smallest dimension of defect is at least 5.3 times its depth	Permitted.
	All quantities more than 0.002 in. (0.051 mm) depth and up to 0.008 in. (0.203 mm) depth if smallest dimension of defect is less than 5.3 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.008 in. (0.203 mm) depth	Not permitted. Contact P&W.
Nicks and pits	All quantities up to 0.001 in. (0.025 mm) depth	Permitted.
	All quantities more than 0.001 in. (0.025 mm) depth and up to 0.008 in. (0.203 mm) depth if smallest dimension of defect is at least 5.3 times its depth	Permitted.
	All quantities more than 0.001 in. (0.025 mm) depth and up to 0.008 in. (0.203 mm) depth if smallest dimension of defect is less than 5.3 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.008 in. (0.203 mm) depth	Not permitted. Contact P&W.
Area M (airfoil trailing edge) for:
Round bottom dents	All quantities up to 0.002 in. (0.051 mm) depth	Permitted.
	All quantities more than 0.002 in. (0.051 mm) depth and up to 0.004 in. (0.102 mm) depth if smallest dimension of defect is at least 9.2 times its depth	Permitted.
	All quantities more than 0.002 in. (0.051 mm) depth and up to 0.004 in. (0.102 mm) depth if smallest dimension of defect is less than 9.2 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.004 in. (0.102 mm) depth	Not permitted. Contact P&W.
Nicks and pits	All quantities up to 0.001 in. (0.025 mm) depth	Permitted.
	All quantities more than 0.001 in. (0.025 mm) depth and up to 0.004 in. (0.102 mm) depth if smallest dimension of defect is at least 9.2 times its depth	Permitted.
	All quantities more than 0.001 in. (0.025 mm) depth and up to 0.004 in. (0.102 mm) depth if smallest dimension of defect is less than 9.2 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.004 in. (0.102 mm) depth	Not permitted. Contact P&W.
NOTE: Coating damage caused by nicks and dents is permitted within the nick and dent limits and does not apply to missing coating.
Aluminide coated areas for:
Missing aluminide coating	More than 0.050 in.2 (32.258 mm2) for each blade	Not permitted. Contact P&W.
All areas for:
Sulfidation or oxidation	All quantities with a minimum loss of parent metal	Not permitted. Contact P&W.
NOTE: Sulfidation is identified as a surface that is green to pale blue in color. NOTE: These damage limits are for continued service use only and are calculated from structural limits and specifications only. If many parts are used that are damaged to these maximum limits, it is possible that decreased engine performance and stability will be the result. It is possible that the parts cannot be repaired at engine overhaul.

EXAMINE	DAMAGE	DISPOSITION
All visible areas of LPT 2nd stage blades for:
Cracks	All quantities	Not permitted. Contact P&W.
Discoloration	Localized hot spots	Not permitted. Contact P&W.
Area A (inner shroud fillet radius) for:
Dents and nicks	All quantities	Not permitted. Contact P&W.
Pits	All quantities more than 0.002 in. (0.051 mm) diameter and more than 0.001 in. (0.025 mm) depth	Not permitted. Contact P&W.
Area B (inner platform fillet radius) for:
Dents and nicks	All quantities	Not permitted. Contact P&W.
Pits	All quantities more than 0.002 in. (0.051 mm) diameter and more than 0.001 in. (0.025 mm) depth	Not permitted. Contact P&W.
Area C (airfoil leading and trailing edges) for:
Round bottom dents	All quantities more than 0.002 in. (0.051 mm) depth	Not permitted. Contact P&W.
Nicks	All quantities more than 0.001 in. (0.025 mm) depth	Not permitted. Contact P&W.
Pits	All quantities more than 0.002 in. (0.051 mm) diameter and more than 0.001 in. (0.025 mm) depth	Not permitted. Contact P&W.
Area D (airfoil leading edge) for:
Round bottom dents	All quantities up to 0.002 in. (0.051 mm) depth	Permitted.
	All quantities more than 0.002 in. (0.051 mm) depth and up to 0.008 in. (0.203 mm) depth if smallest dimension of defect is at least 5.3 times its depth	Permitted.
	All quantities more than 0.002 in. (0.051 mm) depth and up to 0.008 in. (0.203 mm) depth if smallest dimension of defect is less than 5.3 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.008 in. (0.203 mm) depth	Not permitted. Contact P&W.
Nicks and pits	All quantities up to 0.001 in. (0.025 mm) depth	Permitted.
	All quantities more than 0.001 in. (0.025 mm) depth and up to 0.008 in. (0.203 mm) depth if smallest dimension of defect is at least 5.3 times its depth	Permitted.
	All quantities more than 0.001 in. (0.025 mm) depth and up to 0.008 in. (0.203 mm) depth if smallest dimension of defect is less than 5.3 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.008 in. (0.203 mm) depth	Not permitted. Contact P&W.
Area E (airfoil) for:
Round bottom dents	All quantities more than 0.004 in. (0.102 mm) depth	Not permitted. Contact P&W.
Nicks	All quantities more than 0.002 in. (0.051 mm) depth	Not permitted. Contact P&W.
Pits	All quantities more than 0.002 in. (0.051 mm) diameter and more than 0.001 in. (0.025 mm) depth	Not permitted. Contact P&W.
Area F (outer shroud flow-path surfaces) for:
Round bottom dents	All quantities more than 0.002 in. (0.051 mm) depth	Not permitted. Contact P&W.
Nicks	All quantities more than 0.001 in. (0.025 mm) depth	Not permitted. Contact P&W.
Area G (inner shroud flow-path surfaces (Area H not included)) for:
Round bottom dents	All quantities more than 0.010 in. (0.254 mm) depth	Not permitted. Contact P&W.
Nicks	All quantities more than 0.005 in. (0.127 mm) depth	Not permitted. Contact P&W.
Area H (front inner platform) for:
LPT 2nd stage vane contact rub-in	All quantities up to 0.020 in. (0.508 mm) depth if smallest dimension of defect is at least 4.5 times its depth	Permitted.
	All quantities up to 0.020 in. (0.508 mm) depth if smallest dimension of defect is less than 4.5 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.020 in. (0.508 mm) depth	Not permitted. Contact P&W.
Round bottom dents	All quantities up to 0.010 in. (0.254 mm) depth	Not permitted. Contact P&W.
Nicks	All quantities more than 0.005 in. (0.127 mm) depth	Not permitted. Contact P&W.
Area J (airfoil leading edge) for:
Round bottom dents	All quantities up to 0.002 in. (0.051 mm) depth	Permitted.
	All quantities more than 0.002 in. (0.051 mm) depth and up to 0.004 in. (0.102 mm) depth if smallest dimension of defect is at least 9.2 times its depth	Permitted.
	All quantities more than 0.002 in. (0.051 mm) depth and up to 0.004 in. (0.102 mm) depth if smallest dimension of defect is less than 9.2 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.004 in. (0.102 mm) depth	Not permitted. Contact P&W.
Nicks and pits	All quantities up to 0.001 in. (0.025 mm) depth	Permitted.
	All quantities more than 0.001 in. (0.025 mm) depth and up to 0.004 in. (0.102 mm) depth if smallest dimension of defect is at least 9.2 times its depth	Permitted.
	All quantities more than 0.001 in. (0.025 mm) depth and up to 0.004 in. (0.102 mm) depth if smallest dimension of defect is less than 9.2 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.004 in. (0.102 mm) depth	Not permitted. Contact P&W.
Area K (airfoil leading edge) for:
Round bottom dents	All quantities up to 0.002 in. (0.051 mm) depth	Permitted.
	All quantities more than 0.002 in. (0.051 mm) depth and up to 0.004 in. (0.102 mm) depth if smallest dimension of defect is at least 5.3 times its depth	Permitted.
	All quantities more than 0.002 in. (0.051 mm) depth and up to 0.004 in. (0.102 mm) depth if smallest dimension of defect is less than 5.3 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.004 in. (0.102 mm) depth	Not permitted. Contact P&W.
Nicks and pits	All quantities up to 0.001 in. (0.025 mm) depth	Permitted.
	All quantities more than 0.001 in. (0.025 mm) depth and up to 0.004 in. (0.102 mm) depth if smallest dimension of defect is at least 5.3 times its depth	Permitted.
	All quantities more than 0.001 in. (0.025 mm) depth and up to 0.004 in. (0.102 mm) depth if smallest dimension of defect is less than 5.3 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.004 in. (0.102 mm) depth	Not permitted. Contact P&W.
Area L (airfoil trailing edge) for:
Round bottom dents	All quantities up to 0.002 in. (0.051 mm) depth	Permitted.
	All quantities more than 0.002 in. (0.051 mm) depth and up to 0.008 in. (0.203 mm) depth if smallest dimension of defect is at least 9.2 times its depth	Permitted.
	All quantities more than 0.002 in. (0.051 mm) depth and up to 0.008 in. (0.203 mm) depth if smallest dimension of defect is less than 9.2 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.008 in. (0.203 mm) depth	Not permitted. Contact P&W.
Nicks and pits	All quantities up to 0.001 in. (0.025 mm) depth	Permitted.
	All quantities more than 0.001 in. (0.025 mm) depth and up to 0.008 in. (0.203 mm) depth if smallest dimension of defect is at least 9.2 times its depth	Permitted.
	All quantities more than 0.001 in. (0.025 mm) depth and up to 0.008 in. (0.203 mm) depth if smallest dimension of defect is less than 9.2 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.008 in. (0.203 mm) depth	Not permitted. Contact P&W.
Area M (airfoil trailing edge) for:
Round bottom dents	All quantities up to 0.002 in. (0.051 mm) depth	permitted.
	All quantities more than 0.002 in. (0.051 mm) depth and up to 0.008 in. (0.203 mm) depth if smallest dimension of defect is at least 5.3 times its depth	Permitted.
	All quantities more than 0.002 in. (0.051 mm) depth and up to 0.008 in. (0.203 mm) depth if smallest dimension of defect is less than 5.3 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.008 in. (0.203 mm) depth	Not permitted. Contact P&W.
Nicks and pits	All quantities up to 0.001 in. (0.025 mm) depth	Permitted.
	All quantities more than 0.001 in. (0.025 mm) depth and up to 0.008 in. (0.203 mm) depth if smallest dimension of defect is at least 5.3 times its depth	Permitted.
	All quantities more than 0.001 in. (0.025 mm) depth and up to 0.008 in. (0.203 mm) depth if smallest dimension of defect is less than 5.3 times its depth	Not permitted. Contact P&W.
	All quantities more than 0.008 in. (0.203 mm) depth	Not permitted. Contact P&W.
NOTE: Coating damage caused by nicks and dents is permitted within the nick and dent limits and does not apply to missing coating.
All areas for:
Missing aluminide coating	More than 0.050 in.2 (32.258 mm2) for each blade	Not permitted. Contact P&W.
All areas for:
Sulfidation or oxidation	All quantities with a minimum loss of parent metal	Not permitted. Contact P&W.
NOTE: Sulfidation is identified as a surface that is green to pale blue in color NOTE: These damage limits are for continued service use only and are calculated from structural limits and specifications only. If many parts are used that are damaged to these maximum limits, it is possible that decreased engine performance and stability will be the result. It is possible that the parts cannot be repaired at engine overhaul.

(d) Table 603: 3rd Stage LPT Blade Borescope Inspection Limits

EXAMINE	DAMAGE	DISPOSITION
All visible areas of 3rd stage LPT blades for:
Cracks	All quantities	Not permitted. Contact P&W.
Discoloration	Localized hot spots	Not permitted. Contact P&W.
NOTE: The minimum spacing between dents, pits, and scratches must be 0.040 in. (1.016 mm) or two times the size, whichever is greater.
Area A (outer platform fillet radius) for:
Dents and pits	All quantities up to 0.002 in. (0.051 mm) depth if the diameter is at least 30 times the depth	Permitted.
	All quantities up to 0.002 in. (0.051 mm) depth if the diameter is less than 30 times the depth	Not permitted. Contact P&W.
	All quantities more than 0.002 in. (0.051 mm) depth	Not permitted. Contact P&W.
Nicks and scratches	All quantities	Not permitted. Contact P&W.
Areas B (inner platform fillet radius) for:
Dents and pits	All quantities up to 0.002 in. (0.051 mm) depth if the diameter is at least 30 times of the depth	Permitted.
	All quantities up to 0.002 in. (0.051 mm) depth it the diameter is less than 30 times the depth	Not permitted. Contact P&W.
	All quantities more than 0.002 in. (0.051 mm) depth	Not permitted. Contact P&W.
Nicks and scratches	All quantities	Not permitted. Contact P&W.
Area C (airfoil leading edge) for:
Dents and pits	All quantities up to 0.002 in. (0.051 mm) depth if the diameter is at least 30 times the depth	Permitted.
	All quantities up to 0.002 in. (0.051 mm) depth if the diameter is less than 30 times the depth	Not permitted. Contact P&W.
	All quantities more than 0.002 in. (0.051 mm) depth	Not permitted. Contact P&W.
Nicks and scratches	All quantities	Not permitted. Contact P&W.
Area D (airfoil trailing edge) for:
Dents and pits	All quantities up to 0.002 in. (0.051 mm) depth if the diameter is at least 30 times the depth	Permitted.
	All quantities up to 0.002 in. (0.051 mm) depth if the diameter is less than 30 times the depth	Not permitted. Contact P&W.
	All quantities more than 0.002 in. (0.051 mm) depth	Not permitted. Contact P&W.
Nicks and scratches	All quantities	Not permitted. Contact P&W.
Area E (airfoil) for:
Dents and pits	All quantities up to 0.002 in. (0.051 mm) depth if the diameter is at least 30 times the depth	Permitted.
	All quantities up to 0.002 in. (0.051 mm) depth if the diameter is less than 30 times the depth	Not permitted. Contact P&W.
	All quantities more than 0.002 in. (0.051 mm) depth	Not permitted. Contact P&W.
Nicks and scratches	All quantities	Not permitted. Contact P&W.
Area F (outer platform flow-path surfaces (fillet radius and Area H not included)) for:
Dents and pits	All quantities up to 0.002 in. (0.051 mm) depth if the diameter is at least 30 times the depth	Permitted.
	All quantities up to 0.002 in. (0.051 mm) depth if the diameter is less than 30 times the depth	Not permitted. Contact P&W.
	All quantities more than 0.002 in. (0.051 mm) depth	Not permitted. Contact P&W.
Nicks	All quantities more than 0.001 in. (0.025 mm) depth or if minimum separation is less than 0.024 in. (0.610 mm)	Not permitted. Contact P&W.
Scratches	All quantities more than 0.001 in. (0.025 mm) depth	Not permitted. Contact P&W
Area G (inner platform flow-path surfaces (fillet radius not included)) for:
Dents and pits	All quantities up to 0.002 in. (0.051 mm) depth if the diameter is at least 30 times the depth	Permitted.
	All quantities up to 0.002 in. (0.051 mm) depth if the diameter is less than 30 times the depth	Not permitted. Contact P&W.
	All quantities more than 0.002 in. (0.051 mm) depth	Not permitted. Contact P&W.
Nicks	All quantities more than 0.001 in. (0.025 mm) depth or if minimum separation is less than 0.024 in. (0.610 mm)	Not permitted. Contact P&W.
Scratches	All quantities more than 0.001 in. (0.025 mm) depth	Not permitted. Contact P&W.
Area H (fillet radius not included) for:
Dents and pits	All quantities up to 0.002 in. (0.051 mm) depth if the diameter is at least 30 times the depth	Permitted.
	All quantities up to 0.002 in. (0.051 mm) depth if the diameter is less than 30 times the depth	Not permitted. Contact P&W.
	All quantities more than 0.002 in. (0.051 mm) depth	Not permitted. Contact P&W.
Nicks and scratches	All quantities	Not permitted. Contact P&W.
NOTE: These damage limits are for continued service use only and are calculated from structural limits and specifications only. If many parts are used that are damaged to these maximum limits, it is possible that decreased engine performance and stability will be the result. It is possible that the parts cannot be repaired at engine overhaul.

(e) Table 604: 2nd Stage LPT Vane Borescope Inspection Limits

EXAMINE	SERVICEABLE REPAIR	REPAIRABLE LIMITS	DISPOSITION/ REPAIR
All visible areas of LPT 2nd stage vanes for:
Cracks	Not permitted	Not repairable	Contact P&W.
Area A (inner and outer fillet radii) for:
Nicks, dents, and pits	All quantities up to 0.002 in. (0.051 mm) depth	Not repairable	Contact P&W.
Area B (airfoils) for:
Nicks, dents, and pits	All quantities up to 0.006 in. (0.152 mm) depth	Not repairable	Contact P&W.
NOTE: Casting bulges (elevated surface structure) up to 0.004 in. (0.102 mm) height and 0.150 in. (3.810 mm) maximum without change of the surface appearance (color or structure) are permitted (in airfoil Area B). These casting bulges support evidence generated during casting / manufacturing.
Chaplet holes	A maximum of five chaplet holes on concave side are permitted with a maximum size 0.030 in. (0.762 mm). Chaplet holes can be elongated two times the hole diameter in each direction	Not repairable	Contact P&W.
Area C (inner and outer shroud flow-path surface) for:
Nicks, dents, and pits	All quantities up to 0.020 in. (0.508 mm) depth	Not repairable	Contact P&W.
Area D (leading edges) for:
Nicks, dents, and pits	All quantities up to 0.003 in. (0.076 mm) depth	Not repairable	Contact P&W.
Area E (trailing edges) for:
Nicks, dents, and pits	All quantities up to 0.006 in. (0.152 mm) depth	Not repairable	Contact P&W.
Aluminide coated areas for:
Missing aluminide coating	All quantities up to 0.050 in.2 (32.258 mm2) on each blade	Not repairable	Contact P&W.
NOTE: Missing aluminide coating in areas with serviceable nicks and dents is permitted

(f) Table 605: 3rd Stage LPT Vane Borescope Inspection Limits

EXAMINE	SERVICEABLE LIMITS	REPAIRABLE LIMITS	DISPOSITION REPAIR
All visible areas of LPT 3rd stage vanes for:
Cracks	Not permitted	Not repairable	Contact P&W.
Chaplet holes on the airfoils	A maximum of five chaplet holes on concave side are permitted with a maximum size of 0.030 in. (0.762 mm). Chaplet holes can be elongated two times the hole diameter in each direction	Not repairable	Contact P&W.
Area A (outer and inner fillet radii) for:
Dents, nicks, and pits	All quantities up to 0.001 in. (0.025 mm) depth	Not repairable	Contact P&W.
Area B (airfoils) for:
Dents, nicks, and pits	All quantities up to 0.007 in. (0.178 mm) depth	Not repairable	Contact P&W.
NOTE: Casting bulges (elevated surface structure) up to 0.004 in. (0.102 mm) height and 0.150 in. (3.810 mm) maximum without change of the surface appearance (color or structure) are permitted (in airfoil Area B). These casting bulges support evidence generated during casting / manufacturing.
Area C (inner airfoils) for:
Dents, nicks, and pits	All quantities up to 0.004 in. (0.102 mm) depth	Not repairable	Contact P&W.
Area D (outer shroud flow-path surface) for:
Dents, nicks, and pits	All quantities up to 0.004 in. (0.102 mm) depth	Not repairable	Contact P&W.
Area E (leading edges) for:
Dents, nicks, and pits	All quantities up to 0.004 in. (0.102 mm) depth	Not repairable	Contact P&W.
Area F (trailing edges) for:
Dents, nicks, and pits	All quantities up to 0.003 in. (0.076 mm) depth	Not repairable	Contact P&W.
Area G (inner shroud flow-path surface) for:
Dents, nicks, and pits	All quantities up to 0.002 in. (0.051 mm) depth	Not repairable	Contact P&W.
All areas for:
Sulfidation and oxidation	Not permitted	Not repairable	Contact P&W.

(9) After completion of the borescope inspection of the LPT, remove the borescope, power cables and equipment from the engine.
(10) Install the AP TIC-1 borescope plug on the TIC, AP LPT-1 and AP LPT-2 borescope plugs on the LPT case (Ref. AMM TASK 72-00-00-400-804).

5. Close-up
Subtask 72-53-00-010-066-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 cowl-doors (Ref. AMM TASK 78-36-00-410-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
451AL, 452AR.
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
461AL, 462AR.

Subtask 72-53-00-440-056-A ** ON A/C NOT FOR ALL

B. Do the reactivation of the thrust reverser system after maintenance (Ref. AMM TASK 78-30-00-440-805).

Subtask 72-53-00-010-067-A ** ON A/C NOT FOR ALL

C. Close Access
(1) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL, 438AR.
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR.
(2) Remove the access platform(s).
(3) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 02:49:44 UTC