DOC AIRBUS | AMM A320FBorescope Inspection of the 1st and 2nd Stage Turbine Blades [PW11]
TASK 72-51-00-290-802-A
Borescope Inspection of the 1st and 2nd Stage Turbine Blades
Refer to the MPD TASK: 725100-W1
BORESCOPE INSPECTION OF THE 1ST AND 2ND STAGE TURBINE BLADES.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Work Zones and Access Panels
C. Referenced Information
3. Job Set-up
Subtask 72-51-00-941-053-A ** ON A/C NOT FOR ALL
Subtask 72-51-00-410-058-A ** ON A/C NOT FOR ALL
[Rev.10 from 2021]
2026.04.01 02:49:38 UTC
Borescope Inspection of the 1st and 2nd Stage Turbine Blades
WARNING:
BE CAREFUL WHEN YOU DO WORK ON THE ENGINE AFTER SHUTDOWN. THE ENGINE CAN STAY HOT FOR A LONG TIME. IF YOU DO NOT OBEY THIS INSTRUCTION, INJURY CAN OCCUR.
WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
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.
CAUTION:
MAKE SURE THE TEMPERATURE IN THE ENGINE IS LESS THAN 150 DEG.F (65.6 DEG.C) BEFORE YOU INSTALL THE FLEXIBLE BORESCOPE IN THE ENGINE. IF THE ENGINE IS HOTTER THAN 150 DEG.F (65.6 DEG.C), THE FLEXIBLE BORESCOPE CAN MELT AND BE DAMAGED.
ZONE: 400
1. Reason for the JobRefer to the MPD TASK: 725100-W1
BORESCOPE INSPECTION OF THE 1ST AND 2ND STAGE TURBINE BLADES.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
| REFERENCE | QTY | DESIGNATION |
|---|---|---|
| No specific | 1 | ACCESS PLATFORM 1M (3 FT)-ADJUSTABLE |
| No specific | 1 | BORESCOPE - FLEXIBLE |
| No specific | AR | COVER - PROTECTION |
| No specific | 1 | THERMOMETER - METAL PROBE TYPE, 0 TO 400 DEG.F |
| No specific | 1 | WRENCH - STANDARD |
| CTE8003 | 1 | SYSTEM BOROSCOPE (VIDEO) |
| PWA110187 | 1 | KIT CONTROL |
| 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 | |
| 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 72-00-00-000-805-A | Removal of the High (N2) Rotor-Turning Equipment |
| TASK 72-00-00-400-804-A | Installation of the Borescope Plugs |
| TASK 72-00-00-400-805-A | Installation of the High (N2) Rotor Turning Equipment |
| 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 |
| TSM 71-00-00-810-853 | Troubleshoot the Engine after a Flame Out - No/Low Fuel Flow event |
| TSM 71-00-00-810-871 | Troubleshoot the Engine after a Flame Out - Fuel Flow Normal event |
Removal of the Borescope Plugs Access Port HPT-1 and Access Port DIFF-1Subtask 72-51-00-941-053-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 72-51-00-010-061-A ** ON A/C NOT FOR ALL (1) Do the procedure to prevent engine motoring
(Ref. AMM TASK 71-00-00-860-833).
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 an ACCESS PLATFORM 1M (3 FT)-ADJUSTABLE in position.
Subtask 72-51-00-040-053-A ** ON A/C NOT FOR ALL (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 an ACCESS PLATFORM 1M (3 FT)-ADJUSTABLE in position.
C. Deactivation of the Thrust Reverser for Maintenance
Subtask 72-51-00-010-062-A ** ON A/C NOT FOR ALL 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 maintenance (Ref. AMM TASK 78-30-00-040-805). 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(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.
CAUTION:
WIPE CLEAN ALL PARTS AND TOOLS AS NECESSARY TO REMOVE UNWANTED DEBRIS AND PREVENT DAMAGE TO THE ENGINE.
Subtask 72-51-00-290-056-A ** ON A/C NOT FOR ALL A. Borescope Inspection of the High Pressure Turbine (HPT) Assembly
(1) Removal of the protection covers:
(2) Operation intervals:
(a) Refer to the Pratt and Whitney engine maintenance program for the recommended intervals for each engine module.
(b) These inspection intervals can be adjusted based on the operator's experience and on the approval of the local regulatory agency.
(c) Operation at the regular inspection interval limits:
1 If the damage of the parts is in the regular inspection limits, the engine can continue in service.
2 The parts will be examined again at the next regular inspection interval.
(d) Operation at the reduced inspection interval limits:
1 If the parts are damaged to the reduced inspection interval limits, the engine can continue in service as noted in the inspection procedure. The parts must be examined again at the reduced inspection interval. The reduced interval is half of the regular interval, unless specified differently. Contact Pratt and Whitney for further instructions.
(e) Operation at the additional reduced inspection interval limits:
1 If the parts are damaged to the reduced inspection interval limits, the engine can continue in service as noted in the inspection procedure. The parts must be examined again at the reduced inspection interval. The reduced interval is a quarter of the regular interval, unless specified differently. Contact Pratt and Whitney for further instructions.
(f) Operation at more than the additional reduced inspection interval limits:
1 If the parts are damaged more than the additional reduced inspection interval limits, the engine cannot continue in service for more than five additional flight cycles unless otherwise specified in the inspection procedure for the parts.
2 The engine must be disassembled for repair or replacement of the damaged parts.
(3) Remove borescope plugs AP DIFF-1 and AP HPT-1, to get access for the borescope inspection of the 1st stage blades (Ref. AMM TASK 72-00-00-000-804).
(4) If the engine has run in the last two hours, do a check of the temperature in the High Pressure Turbine (HPT) with the THERMOMETER - METAL PROBE TYPE, 0 TO 400 DEG.F.
(a) It is recommended that you wait three to five hours after the engine shutdown before you do a borescope inspection.
(b) The procedure to dry-motor the engine with the starter to decrease the engine core temperature is optional (Ref. AMM TASK 71-00-00-860-817).
(5) Remove the main gearbox manual crank cover and install the PWA110187 KIT CONTROL or a manual wrench on the drive adapter to turn the N2 rotor (Ref. AMM TASK 72-00-00-400-805).
(6) Turn the HPT assembly:
(7) Use the WRENCH - STANDARD or the optional PWA110187 KIT CONTROL on the gearbox to turn the HPT rotor so that you can see all of the HPT blades:
(a) Turn the HPT rotor slowly and stop so that you can carefully examine each blade.
(8) Do the inspection with the CTE8003 SYSTEM BOROSCOPE (VIDEO) or equivalent.
(9) Remove the diffuser case plug AP DIFF-1 at the 3 o'clock location on the diffuser case to view the HPT 1st blade leading edges:
(a) Remove plug AP HPT-1 at the 5 o'clock position on the HPT to view the HPT 1st blade trailing edges and HPT 2nd blade leading edges.
(b) Remove plug AP TIC-1 at the 1:30 o'clock position to view the HPT 2nd blade trailing edge.
(b) Do a borescope inspection of the HPT 2nd stage blade leading and trailing edges. There are 44 HPT 2nd stage blades. Use AP HPT-1 for access. AP TIC-1 can be used with a guide tube to inspect the trailing edge of the HPT 2nd stage blades.
Table 601 - Borescope Inspection of the HPT 1st Stage Blade
Table 602 - Borescope Inspection of the HPT 2nd Stage Blade
(11) Install borescope plugs AP DIFF-1, AP HPT-1 and AP TIC-1 (Ref. AMM TASK 72-00-00-400-804).
(12) Remove the PWA110187 KIT CONTROL or the manual wrench from the main-gearbox drive adapter and install the main-gearbox manual crank-cover (Ref. AMM TASK 72-00-00-000-805).
(13) Remove the high (N2) rotor-turning equipment (Ref. AMM TASK 72-00-00-000-805).
(14) Install the borescope plugs (Ref. AMM TASK 72-00-00-400-804).
(15) Examine the assembly for foreign objects, damage and correct assembly.
(16) Installation of the protection covers:
5. Close-up(1) Removal of the protection covers:
CAUTION:
REMOVE THE PROTECTION COVERS FROM THE OPENINGS AS NECESSARY TO PREVENT ENGINE DAMAGE.
(a) Make sure that you remove all the necessary COVER - PROTECTION to prevent damage to the engine. (2) Operation intervals:
(a) Refer to the Pratt and Whitney engine maintenance program for the recommended intervals for each engine module.
(b) These inspection intervals can be adjusted based on the operator's experience and on the approval of the local regulatory agency.
(c) Operation at the regular inspection interval limits:
1 If the damage of the parts is in the regular inspection limits, the engine can continue in service.
2 The parts will be examined again at the next regular inspection interval.
(d) Operation at the reduced inspection interval limits:
1 If the parts are damaged to the reduced inspection interval limits, the engine can continue in service as noted in the inspection procedure. The parts must be examined again at the reduced inspection interval. The reduced interval is half of the regular interval, unless specified differently. Contact Pratt and Whitney for further instructions.
(e) Operation at the additional reduced inspection interval limits:
1 If the parts are damaged to the reduced inspection interval limits, the engine can continue in service as noted in the inspection procedure. The parts must be examined again at the reduced inspection interval. The reduced interval is a quarter of the regular interval, unless specified differently. Contact Pratt and Whitney for further instructions.
(f) Operation at more than the additional reduced inspection interval limits:
1 If the parts are damaged more than the additional reduced inspection interval limits, the engine cannot continue in service for more than five additional flight cycles unless otherwise specified in the inspection procedure for the parts.
2 The engine must be disassembled for repair or replacement of the damaged parts.
(3) Remove borescope plugs AP DIFF-1 and AP HPT-1, to get access for the borescope inspection of the 1st stage blades (Ref. AMM TASK 72-00-00-000-804).
(4) If the engine has run in the last two hours, do a check of the temperature in the High Pressure Turbine (HPT) with the THERMOMETER - METAL PROBE TYPE, 0 TO 400 DEG.F.
(a) It is recommended that you wait three to five hours after the engine shutdown before you do a borescope inspection.
(b) The procedure to dry-motor the engine with the starter to decrease the engine core temperature is optional (Ref. AMM TASK 71-00-00-860-817).
(5) Remove the main gearbox manual crank cover and install the PWA110187 KIT CONTROL or a manual wrench on the drive adapter to turn the N2 rotor (Ref. AMM TASK 72-00-00-400-805).
(6) Turn the HPT assembly:
CAUTION:
ONLY TURN THE ENGINE IN THE CORRECT DIRECTION OF OPERATION. IF YOU DO NOT OBEY THIS INSTRUCTION, YOU WILL CAUSE DAMAGE TO THE ENGINE.
CAUTION:
BEFORE YOU REMOVE THE N2 CRANK-PAD COVER, PUT A CONTAINER IN POSITION BELOW IT TO COLLECT THE UNWANTED OIL.
THE MAIN GEARBOX OIL-LEVEL CAN BE HIGHER THAN THE N2 CRANK-PAD COVER IF THE ENGINE DID NOT OPERATE DURING EIGHT HOURS.
IF YOU DO NOT OBEY THIS INSTRUCTION, OIL CAN SPILL AND CAUSE DAMAGE TO THE ENGINE PARTS.
(a) The HPT assembly must be turned clockwise (aft looking forward) while you do this inspection. (7) Use the WRENCH - STANDARD or the optional PWA110187 KIT CONTROL on the gearbox to turn the HPT rotor so that you can see all of the HPT blades:
(a) Turn the HPT rotor slowly and stop so that you can carefully examine each blade.
(8) Do the inspection with the CTE8003 SYSTEM BOROSCOPE (VIDEO) or equivalent.
(9) Remove the diffuser case plug AP DIFF-1 at the 3 o'clock location on the diffuser case to view the HPT 1st blade leading edges:
(a) Remove plug AP HPT-1 at the 5 o'clock position on the HPT to view the HPT 1st blade trailing edges and HPT 2nd blade leading edges.
(b) Remove plug AP TIC-1 at the 1:30 o'clock position to view the HPT 2nd blade trailing edge.
NOTE: The BORESCOPE - FLEXIBLE is required to view the leading edges of the HPT 1st stage blades.
(10) Borescope inspection: 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.
(a) Do a borescope inspection of the HPT 1st stage blade leading and trailing edges. There are 44 HPT 1st stage blades. Use AP DIFF-1 and AP HPT-1 for access. (b) Do a borescope inspection of the HPT 2nd stage blade leading and trailing edges. There are 44 HPT 2nd stage blades. Use AP HPT-1 for access. AP TIC-1 can be used with a guide tube to inspect the trailing edge of the HPT 2nd stage blades.
Table 601 - Borescope Inspection of the HPT 1st Stage Blade
| EXAMINE | DAMAGE | DISPOSITION |
|---|---|---|
| Airfoil for: | | |
| Cracks | Cracks that form through other cracks. | Remove the engine in 30 cycles or less. |
| | Cracks that form closed loops between cooling holes. | Remove the engine in five cycles or less. |
| Rounding | Rounding is permitted in area F on the airfoil Leading Edge (LE) if the tangency to the LE does not extend more than 0.050 in. (1.270 mm) below the tip shelf and the LE cavity is not shown. | Permitted for reduced inspection interval limit. |
| | Rounding is permitted in area F on the airfoil LE if the tangency to the LE extends more than 0.050 in. (1.270 mm) below the tip shelf and the LE cavity is not shown. | Permitted for additional reduced inspection interval limit. |
| | Rounding that causes the internal cavity to be shown. | Remove the engine in 10 cycles or less. |
| 1st stage blade area A for: | | |
| Oxidation and erosion | All quantities of burning, erosion, or surface discoloration are permitted if there is no missing blade material. | Permitted for reduced inspection interval limit. |
| | Burning or erosion of the base material of the blade that causes missing base material. | Permitted for additional reduced inspection interval limit. |
| | Oxidation or erosion that causes a through-hole that exposes the cooling cavity no more than 0.100 in. (2.540 mm) total each blade in radial length and does not contact the impingement rib. No more than five blades each rotor. | Permitted for 375-hour interval. |
| | Oxidation or erosion that causes a through-hole that exposes the cooling cavity no more than 0.500 in. (12.7000 mm) total each blade in radial length and does not contact the impingement rib. No more than four blades each rotor. | Permitted for 375-hour inspection interval. |
| | Oxidation or erosion that causes a through-hole that exposes the cooling cavity more than 0.500 in. (12.7000 mm). | Remove the engine in ten cycles or less. |
| | All quantities of burning or erosion of the internal impingement rib. | Remove the engine in five cycles or less. |
| 1st stage blade area A for: | | |
| Cracks, nicks and dents | Crack less than 0.080 in. (2.032 mm), can connect to two cooling holes or less. | Permitted for regular inspection interval. |
| | Crack between 0.080 in. (2.032 mm) and 0.100 in. (2.540 mm), can connect two cooling holes or less. | Permitted for reduced inspection interval limit. |
| | Crack between 0.100 in. (2.540 mm) and 0.120 in. (3.048 mm), can connect two cooling holes or less. | Permitted for additional reduced inspection interval limit. |
| | Crack between 0.120 in. (3.048 mm) and 0.140 in. (3.556 mm), can connect two cooling holes or less. | Remove the engine in 30 cycles or less. |
| | Crack 0.140 in. (3.556 mm) in length, can connect two cooling holes or less. | Remove the engine in 10 cycles or less. |
| | Crack longer than 0.140 in. (3.556 mm). | Remove the engine in five cycles or less. |
| | Crack extends from burned area and is less than 0.080 in. (2.032 mm) in length (combination of a burn and crack). | Permitted for regular inspection interval. |
| | Crack extends from burned area and is between 0.080 in. (2.032 mm) and 0.100 in. (2.540 mm) in length (combination of a burn and crack). | Permitted for reduced inspection interval limit. |
| | Crack extends from burned area and is between 0.100 in. (2.540 mm) and 0.120 in. (3.048 mm) in length (combination of a burn and crack). | Permitted for additional reduced inspection interval limit. |
| | Crack extends from burned area and is between 0.120 in. (3.048 mm) and 0.140 in. (3.556 mm) in length (combination of a burn and crack). | Remove the engine in 30 cycles or less. |
| | Crack extends from burned area and is 0.140 in. (3.556 mm) in length (combination of a burn and crack). | Remove the engine in 10 cycles or less. |
| | Crack extends from burned area and is longer than 0.140 in. (3.556 mm) in length (combination of a burn and crack). | Remove the engine in five cycles or less. |
| | Nick or dent has a diameter less than 0.080 in. (2.032 mm). | Permitted for regular inspection interval. |
| | Nick or dent has a diameter between 0.080 in. (2.032 mm) and 0.100 in. (2.540 mm). | Permitted for reduced inspection interval limit. |
| | Nick or dent has a diameter between 0.100 in. (2.540 mm) and 0.120 in. (3.048 mm). | Permitted for additional reduced inspection interval limit. |
| | Nick or dent has a diameter between 0.120 in. (3.048 mm) and 0.140 in. (3.556 mm). | Remove the engine in 30 cycles or less. |
| | Nick or dent has a diameter of 0.140 in. (3.556 mm). | Remove the engine in 10 cycles or less. |
| | Nick or dent has a diameter more than 0.140 in. (3.556 mm). | Remove the engine in five cycles or less. |
| | Crack extends from nick or dent is less than 0.080 in. (2.032 mm) (combination of a nick or dent and crack). | Permitted for regular inspection interval. |
| | Crack extends from nick or dent is between 0.080 in. (2.032 mm) and 0.100 in. (2.540 mm) (combination of a nick or dent and crack). | Permitted for reduced inspection interval limit. |
| | Crack extends from nick or dent is between 0.100 in. (2.540 mm) and 0.120 in. (3.048 mm) (combination of a nick or dent and crack). | Permitted for additional reduced inspection interval limit. |
| | Crack extends from nick or dent is between 0.120 in. (3.048 mm) and 0.140 in. (3.556 mm) (combination of a nick or dent and crack). | Remove the engine in 30 cycles or less. |
| | Crack extends from nick or dent is 0.140 in. (3.556 mm) in length (combination of a nick or dent and crack). | Remove the engine in 10 cycles or less. |
| | Crack extends from nick or dent is longer than 0.140 in. (3.556 mm) (combination of a nick or dent and crack). | Remove the engine in five cycles or less. |
| | Nick or dent shows signs of torn metal. | Remove the engine in 10 cycles or less. |
| | One nick or dent that causes a through-hole that exposes the cooling cavity no more than 0.100 in. (2.540 mm) total each blade in radial length and does not contact the impingement rib. No more than five blades each rotor. | Permitted for 375-hour interval. |
| | More than one nick or dent that causes a through-hole that exposes the cooling cavity to no more than a dimension of 0.500 IN. (12.700 MM). | Remove the engine in ten cycles or less. |
| | Nicks and dents that cause a through-hole that exposes the cooling cavity no more than 0.500 IN. (12.700 MM) total each blade in radial length and does not contact the impingement rib. No more than four blades each rotor. | Permitted for 375-hour inspection interval. |
| Missing, chipped or flaked coating | All quantities | Permitted for regular inspection interval. |
| Leading edge for blocked cooling holes | Three blocked cooling holes or less on the leading edge Outside Diameter (OD) in 60 to 100 percent of span. | Permitted for regular inspection interval. |
| | More than three blocked cooling holes on the leading edge OD within 60 to 100 percent of span. | Permitted for reduced inspection interval limit. |
| Area B for: | | |
| Oxidation and erosion | All quantities of burning, erosion or surface discoloration are permitted if there is no missing blade material. | Permitted for reduced inspection interval limit. |
| | Burning or erosion of the base material of the blade that causes missing base material. | Permitted for additional reduced inspection interval limit. |
| | All quantities of burning, erosion or surface discoloration that cause burn through to the internal cavity. | Remove the engine in 10 cycles or less. |
| | All quantities of burning or erosion of the internal impingement rib. | Remove the engine in five cycles or less. |
| Cracks, nicks or dents | Crack less than 0.040 in. (1.016 mm) can connect two cooling holes or less. | Permitted for regular inspection interval. |
| | Crack between 0.040 in. (1.016 mm) and 0.060 in. (1.524 mm) can connect two cooling holes or less. | Permitted for reduced inspection interval limit. |
| | Crack between 0.060 in. (1.524 mm) and 0.080 in. (2.032 mm) can connect two cooling holes or less. | Permitted for additional reduced inspection interval limit. |
| | Crack between 0.080 in. (2.032 mm) and 0.100 in. (2.540 mm) can connect two cooling holes or less. | Remove the engine in 30 cycles or less. |
| | Crack 0.100 in. (2.540 mm) in length. Can connect two cooling holes or less. | Remove the engine in 10 cycles or less. |
| | Crack longer than 0.100 in. (2.540 mm) | Remove the engine in five cycles or less. |
| | Cracks connecting three or more cooling holes or closed-loop cracks through to the base metal. | Remove the engine in five cycles or less. |
| | Crack extends from burned area and is less than 0.040 in. (1.016 mm) in length (combination of burn and crack). | Permitted for regular inspection interval. |
| | Crack extends from burned area and is between 0.040 in. (1.016 mm) and 0.060 in. (1.524 mm) in length (combination of burn and crack). | Permitted for reduced inspection interval limit. |
| | Crack extends from burned area and is between 0.060 in. (1.524 mm) and 0.080 in. (2.032 mm) in length (combination of burn and crack). | Permitted for additional reduced inspection interval limit. |
| | Crack extends from burned area and is between 0.080 in. (2.032 mm) and 0.100 in. (2.540 mm) in length (combination of burn and crack). | Remove the engine in 30 cycles or less. |
| | Crack extends from burned area and is 0.100 in. (2.540 mm) in length (combination of burn and crack). | Remove the engine in 10 cycles or less. |
| | Crack extends from burned area and is longer than 0.100 in. (2.540 mm) (combination of burn and crack). | Remove the engine in five cycles or less. |
| | Nick or dent has a diameter less than 0.040 in. (1.016 mm). | Permitted for regular inspection interval. |
| | Nick or dent has a diameter between 0.040 in. (1.016 mm) and 0.060 in. (1.524 mm). | Permitted for reduced inspection interval limit. |
| | Nick or dent has a diameter between 0.060 in. (1.524 mm) and 0.080 in. (2.032 mm). | Permitted for additional reduced inspection interval limit. |
| | Nick or dent has a diameter between 0.080 in. (2.032 mm) and 0.100 in. (2.540 mm). | Remove the engine in 30 cycles or less. |
| | Nick or dent has a diameter of 0.100 in. (2.540 mm). | Remove the engine in 10 cycles or less. |
| | Nick or dent has a diameter more than 0.100 in. (2.540 mm). | Remove the engine in five cycles or less. |
| | Nick or dent shows signs of torn metal. | Remove the engine in 10 cycles or less. |
| | Nick or dent causes internal areas to show. | Remove the engine in 10 cycles or less. |
| Missing, chipped or flaked coating | All quantities | Permitted for regular inspection interval. |
| Area C for: | | |
| Oxidation and erosion | All quantities of burning, erosion or surface discoloration are permitted if there is no missing blade material. | Permitted for additional reduced inspection interval limit. |
| | Burning or erosion of the base material of the blade that causes missing base material. | Remove the engine in 10 cycles or less. |
| | All quantities of burning, erosion or surface discoloration that cause burn through to the internal cavity. | Remove the engine in five cycles or less. |
| Cracks, nicks or dents | All quantities of cracks, nicks or dents | Remove the engine in five cycles or less. |
| Missing, chipped or flaked coating | 50 percent or less of surface area spalled, chipped or flaked | Permitted for regular inspection interval. |
| Area D for: | | |
| Oxidation and erosion | All quantities of burning, erosion or surface discoloration are permitted if there is no missing blade material. | Permitted for reduced inspection interval limit. |
| | Burning or erosion of the base material of the blade that causes complete material loss up to 0.050 in. (1.270 mm) from the trailing edge, over all the radial lengths. | Permitted for additional reduced inspection interval limit. |
| | Burning or erosion of the base material of the blade that causes complete material loss between 0.050 in. (1.270 mm) and 0.100 in. (2.540 mm) from the trailing edge, over all the radial lengths. | Remove the engine in 10 cycles or less. |
| | Burning or erosion of the blade base material that causes complete material loss across 0.100 in. (2.540 mm) from the trailing edge, along all the radial lengths. | Remove the engine in five cycles or less. |
| Cracks, nicks or dents | Crack less than 0.120 in. (3.048 mm) | Permitted for regular inspection interval. |
| | Crack between 0.120 in. (3.048 mm) and 0.150 in. (3.810 mm) | Permitted for reduced inspection interval limit. |
| | Crack between 0.150 in. (3.810 mm) and 0.180 in. (4.572 mm) | Permitted for additional reduced inspection interval limit. |
| | Crack between 0.180 in. (4.572 mm) and 0.190 in. (4.826 mm) | Remove the engine in 30 cycles or less. |
| | Crack between 0.190 in. (4.826 mm) and 0.200 in. (5.080 mm) | Remove the engine in 10 cycles or less. |
| | Crack longer than 0.200 in. (5.080 mm) | Remove the engine in five cycles or less. |
| | Nick or dent with a diameter less than 0.120 in. (3.048 mm) | Permitted for regular inspection interval. |
| | Nick or dent with a diameter between 0.120 in. (3.048 mm) and 0.150 in. (3.810 mm) | Permitted for reduced inspection interval limit. |
| | Nick or dent with a diameter between 0.150 in. (3.810 mm) and 0.180 in. (4.572 mm) | Permitted for additional reduced inspection interval limit. |
| | Nick or dent with a diameter between 0.180 in. (4.572 mm) and 0.190 in. (4.826 mm) | Remove the engine in 30 cycles or less. |
| | Nick or dent with a diameter between 0.190 in. (4.826 mm) and 0.200 in. (5.080 mm) | Remove the engine in 10 cycles or less. |
| | Nick or dent with a diameter more than or equal to 0.200 in. (5.080 mm) | Remove the engine in five cycles or less. |
| | Crack that extends from a nick or dent is less than 0.120 in. (3.048 mm) (combination of a nick or dent and crack). | Permitted for regular inspection interval. |
| | Crack that extends from a nick or dent is between 0.120 in. (3.048 mm) and 0.150 in. (3.810 mm) (combination of a nick or dent and crack). | Permitted for reduced inspection interval limit. |
| | Crack that extends from a nick or dent is between 0.150 in. (3.810 mm) and 0.180 in. (4.572 mm) (combination of a nick or dent and crack). | Permitted for additional reduced inspection interval limit. |
| | Crack that extends from a nick or dent is between 0.180 in. (4.572 mm) and 0.190 in. (4.826 mm) (combination of a nick or dent and crack). | Remove the engine in 30 cycles or less. |
| | Crack that extends from a nick or dent is between 0.190 in. (4.826 mm) and 0.200 in. (5.080 mm) (combination of a nick or dent and crack). | Remove the engine in 10 cycles or less. |
| | Crack extends from nick or dent is equal to or longer than 0.200 in. (5.080 mm) in length (combination of a nick or dent and crack). | Remove the engine in five cycles or less. |
| | Nick or dent shows signs of torn metal. | Remove the engine in 10 cycles or less. |
| | Nick or dent causes internal areas to show. | Remove the engine in 10 cycles or less. |
| Missing, chipped or flaked coating | All quantities | Permitted for regular inspection interval. |
| Area E for: | | |
| Oxidation and erosion | All quantities of burning, erosion or surface discoloration are permitted if there is no missing blade material. | Permitted for reduced inspection interval limit. |
| | Burning or erosion of the base material of the blade that causes complete material loss a maximum of 0.050 in. (1.270 mm) from the trailing edge, over all the radial lengths. | Permitted for additional reduced inspection interval limit. |
| | Burning or erosion of the base material of the blade that causes complete material loss between 0.050 in. (1.270 mm) and 0.100 in. (2.540 mm) from the trailing edge, over all the radial lengths. | Remove the engine in 10 cycles or less. |
| | Burning or erosion of the base material of the blade that causes complete material loss between 0.100 in. (2.540 mm) and 0.320 in. (8.128 mm) from the trailing edge, over all the radial lengths. | Remove the engine in five cycles or less. |
| | Burning or erosion of the base material of the blade that results in complete material loss over 0.320 in. (8.128 mm) from the trailing edge, over all the radial lengths. | Remove the engine in five cycles or less. |
| Cracks, nicks or dents | Crack less than 0.100 in. (2.540 mm) | Permitted for regular inspection interval. |
| | Crack between 0.100 in. (2.540 mm) and 0.130 in. (3.302 mm) | Permitted for reduced inspection interval limit. |
| | Crack between 0.130 in. (3.302 mm) and 0.160 in. (4.064 mm) | Permitted for additional reduced inspection interval limit. |
| | Crack between 0.160 in. (4.064 mm) and 0.180 in. (4.572 mm) | Remove the engine in 30 cycles or less. |
| | Crack between 0.180 in. (4.572 mm) and 0.190 in. (4.826 mm) | Remove the engine in 10 cycles or less. |
| | Crack 0.190 in. (4.826 mm) or longer | Remove the engine in five cycles or less. |
| | Nick or dent with a diameter less than 0.100 in. (2.540 mm) | Permitted for regular inspection interval. |
| | Nick or dent with a diameter between 0.100 in. (2.540 mm) and 0.130 in. (3.302 mm) | Permitted for reduced inspection interval limit. |
| | Nick or dent with a diameter between 0.130 in. (3.302 mm) and 0.160 in. (4.064 mm) | Permitted for additional reduced inspection interval limit. |
| | Nick or dent with a diameter between 0.160 in. (4.064 mm) and 0.180 in. (4.572 mm) | Remove the engine in 30 cycles or less. |
| | Nick or dent with a diameter between 0.180 in. (4.572 mm) and 0.190 in. (4.826 mm) | Remove the engine in 10 cycles or less. |
| | Nick or dent with a diameter equal to or larger than 0.190 in. (4.826 mm) | Remove the engine in five cycles or less. |
| | Crack extends from nick or dent is less than 0.100 in. (2.540 mm) (combination of a nick or dent and crack). | Permitted for regular inspection interval. |
| | Crack extends from nick or dent is between 0.100 in. (2.540 mm) and 0.130 in. (3.302 mm) (combination of a nick or dent and crack). | Permitted for reduced inspection interval limit. |
| | Crack extends from nick or dent is between 0.130 in. (3.302 mm) and 0.160 in. (4.064 mm) (combination of a nick or dent and crack). | Permitted for additional reduced inspection interval limit. |
| | Crack extends from nick or dent is between 0.160 in. (4.064 mm) and 0.180 in. (4.572 mm) (combination of a nick or dent and crack). | Remove the engine in 30 cycles or less. |
| | Crack extends from nick or dent is between 0.180 in. (4.572 mm) and 0.190 in. (4.826 mm) (combination of a nick or dent and crack). | Remove the engine in 10 cycles or less. |
| | Crack extends from nick or dent is larger than or equal to 0.190 in. (4.826 mm) in length (combination of a nick or dent and crack). | Remove the engine in five cycles or less. |
| | Nick or dent shows signs of torn metal. | Remove the engine in 10 cycles or less. |
| | Nick or dent causes internal areas to show. | Remove the engine in 10 cycles or less. |
| Missing, chipped or flaked coating | All quantities | Permitted for regular inspection interval. |
| Area F for: | | |
| Oxidation and erosion | All quantities of burning, erosion or surface discoloration are permitted if there is no missing blade material. | Permitted for regular inspection interval. |
| | Burning or erosion of the base material up to tip shelf base (concave side view only). | Permitted for additional reduced inspection interval limit. |
| | Burning or erosion of the parent material more than the tip shelf by any length. | Remove the engine in 10 cycles or less. |
| | All quantities of burning, erosion or surface discoloration that cause burn through to the internal cavity. | Remove the engine in 10 cycles or less. |
| | Burning or erosion of the base material up to or through the first row of pressure surface film cooling holes. | Remove the engine in five cycles or less. |
| Cracks, nicks or dents | Nick or dent has a diameter less than or equal to 0.045 in. (1.143 mm) (torn metal permitted). | Remove the engine in 30 cycles or less. |
| | Nick or dent has a diameter more than 0.045 in. (1.143 mm) (torn metal permitted). | Remove the engine in five cycles or less. |
| Area F: Blade tip for: | | |
| Cracks | A radial crack is permitted if it is in the radial direction no more than 0.065 in. (1.6510 mm) in length. | Permitted 675 hours/374 cycles. Inspection interval limit. |
| | A radial crack is permitted if it is in the radial direction more than 0.065 in. (1.6510 mm) and no more than 0.150 in. (3.8100 mm) in length and the ratio between the 'perpendicular distance from the inboard end of crack to tip edge' (A) and the 'length of the crack' (B) is more than 0.96, on a deviated crack. | Permitted 375 hours/187 cycles. Inspection interval limit. |
| | A radial crack more than 0.150 in. (3.8100 mm) in length from the radial direction or ratio between 'perpendicular distance from inboard end of crack to tip edge' [A] and the 'length of the crack' [B] is less than 0.96, on a deviated crack. | Remove the engine in five cycles or less. |
| Missing, chipped or flaked coating | All quantities | Permitted for regular inspection interval. |
| Rounding | Rounding is permitted in area F on the airfoil LE if the tangency to the LE does not extend more than 0.050 in. (1.270 mm) below the tip shelf and the LE cavity is not shown. | Permitted for additional reduced inspection interval limit. |
| Area G for: | | |
| Oxidation and erosion | All quantities | Remove the engine in 10 cycles or less. |
| Cracks | All quantities of cracks (or combination of a crack and a burn) that do not start from the platform edge. | Remove the engine in five cycles or less. |
| Missing, chipped or flaked coating | All quantities | Permitted for regular inspection interval. |
| Area H for: | | |
| Oxidation and erosion | All quantities of burning, erosion or surface discoloration are permitted if there is no missing blade material. | Permitted for reduced inspection interval limit. |
| Platform edge for rounding, oxidation, and erosion: | | |
| Superficial | Minor spall, oxidation, and 1B-2V gap covered. | Permitted for regular inspection interval. |
| Minor | Platform still separates gaspath and under-platform region. 1B-2V gap covered. No more than 20 blades. | Permitted for reduced inspection interval. |
| | Platform still separates gaspath and under-platform region. 1B-2V gap covered. More than 20 blades. | Permitted for additional reduced inspection interval. |
| Moderate | Rounding visible. Oxidation through 100 percent of platform wall. Small gap 1B-2V interface exposed to gaspath. No more than 20 blades. | Permitted for additional reduced inspection interval. |
| | Rounding visible. Oxidation through 100 percent of platform wall. Small gap 1B-2V interface exposed to gaspath. More than 20 blades. | Contact P&W. |
| Severe | Rounding up to first row of S/S platform cooling holes. Additional part of under-platform exposed to gaspath. No more than ten blades. | Permitted for additional reduced inspection interval. |
| | Rounding up to first row of S/S platform cooling holes. Additional part of under-platform exposed to gaspath. More than ten blades. | Contact P&W. |
| Cracks | All quantities of cracks. | Remove the engine in 10 cycles or less. |
| Missing, chipped or flaked coating | All quantities | Permitted for regular inspection interval. |
| Area J for: | | |
| Oxidation and erosion | All quantities of burning, erosion or surface discoloration are permitted if there is no missing blade material. | Permitted for additional reduced inspection interval limit. |
| | Burning or erosion of the base material of the blade that causes missing base material. | Remove the engine in 10 cycles or less. |
| Cracks | Crack less than 0.070 in. (1.778 mm) and does not go into the platform-to-airfoil fillet radius. Multiple cracks permitted. | Permitted for regular inspection interval. |
| | Crack is between 0.070 in. (1.778 mm) and 0.085 in. (2.159 mm) and does not go into the platform-to-airfoil fillet radius. Multiple cracks permitted. | Permitted for reduced inspection interval limit. |
| | Crack is between 0.085 in. (2.159 mm) and 0.100 in. (2.540 mm) and does not go into the platform-to-airfoil fillet radius. Multiple cracks permitted. | Permitted for additional reduced inspection interval limit. |
| | Crack is between 0.100 in. (2.540 mm) and 0.120 in. (3.048 mm) and does not go into the platform-to-airfoil fillet radius. | Remove the engine in 30 cycles or less. |
| | Crack is longer than 0.120 in. (3.048 mm) and does not go into the platform-to-airfoil fillet radius. | Remove the engine in 10 cycles or less. |
| | Crack of all lengths goes into the platform-to-airfoil fillet radius, but not through. Crack does not turn. Only one crack permitted. | Permitted for additional reduced inspection interval limit. |
| | Crack of all lengths goes through the platform-to-airfoil fillet radius or turns and runs with airfoil fillet. | Remove the engine in 10 cycles or less. |
| | All quantities of platform lifting. | Remove the engine in 10 cycles or less. |
| Missing, chipped or flaked coating | All quantities | Permitted for regular inspection interval. |
| Area K for: | | |
| Oxidation and erosion | All quantities of burning, erosion or surface discoloration are permitted if there is no missing blade material. | Permitted for additional reduced inspection interval limit. |
| | Burning or erosion of the base material of the blade that causes missing base material. | Remove the engine in 10 cycles or less. |
| Cracks | Crack less than 0.100 in. (2.540 mm) and does not go into the platform-to-airfoil fillet radius. Multiple cracks permitted. | Permitted for regular inspection interval. |
| | Crack is between 0.100 in. (2.540 mm) and 0.120 in. (3.048 mm) and does not go into the platform-to-airfoil fillet radius. Multiple cracks permitted. | Permitted for reduced inspection interval limit. |
| | Crack is between 0.120 in. (3.048 mm) and 0.140 in. (3.556 mm) and does not go into the platform-to-airfoil fillet radius. Multiple cracks permitted. | Permitted for additional reduced inspection interval limit. |
| | Crack is between 0.140 in. (3.556 mm) and 0.170 in. (4.318 mm) and does not go into the platform-to-airfoil fillet radius. | Remove the engine in 30 cycles or less. |
| | Crack is longer than 0.170 in. (4.318 mm) and does not go into the platform-to-airfoil fillet radius. | Remove the engine in 10 cycles or less. |
| | Crack of all lengths goes into the platform-to-airfoil fillet radius, but not through. Crack does not turn. Only one crack permitted. | Permitted for additional reduced inspection interval limit. |
| | Crack of all lengths goes through the platform-to-airfoil fillet radius or turns and runs with airfoil fillet. | Remove the engine in 10 cycles or less. |
| | All quantities of platform lifting. | Remove the engine in 10 cycles or less. |
| Missing, chipped or flaked coating | All quantities | Permitted for regular inspection interval. |
| Area L for: | | |
| Oxidation and erosion | All quantities of burning, erosion or surface discoloration are permitted if there is no missing blade material. | Permitted for additional reduced inspection interval limit. |
| | Burning or erosion of the base material of the blade that causes missing base material. | Remove the engine in 10 cycles or less. |
| Cracks | All quantities of cracks | Remove the engine in 10 cycles or less. |
| Missing, chipped or flaked coating | All quantities | Permitted for regular inspection interval. |
| Area M for: | | |
| Oxidation and erosion | All quantities of burning, erosion or surface discoloration are permitted if there is no missing blade material. | Permitted for reduced inspection interval limit. |
| | Burning or erosion of the base material of the blade that causes missing base material. | Remove the engine in 10 cycles or less. |
| Cracks | All quantities of cracks | Remove the engine in 10 cycles or less. |
| Missing, chipped or flaked coating | All quantities | Permitted for regular inspection interval. |
| EXAMINE | DAMAGE | DISPOSITION |
|---|---|---|
| Area A for: | | |
| Oxidation and erosion | All quantities of burning, erosion or surface discoloration provided no monitorable change in surface profile (missing blade material). | Permitted for regular inspection interval limit. |
| | Burning or erosion of the base material of the blade that results in a monitorable change in the surface profile (missing base material). | Permitted for reduced inspection interval limit. |
| | All quantities of burning, erosion or surface discoloration, that results in burn through to internal cavity. | Remove the engine in less than 10 cycles. |
| Cooling holes | No more than three blocked cooling holes are permitted for: blocked cooling on the leading edge outer diameter holes. | Permitted for regular inspection interval limit. |
| | More than three blocked cooling holes are permitted for: blocked cooling on the leading edge outer diameter holes. | Permitted for reduced inspection interval limit. |
| Cracks | Crack 0.100 in. (2.540 mm) or less. May connect no more than two cooling holes. | Permitted for regular inspection interval limit. |
| | Crack longer than 0.100 in. (2.540 mm) may connect no more than two cooling holes. | Permitted for reduced inspection interval limit. |
| | Crack longer than 0.105 in. (2.667 mm) may connect no more than two cooling holes. | Permitted for additional reduced inspection interval limit. |
| | Crack longer than 0.110 in. (2.794 mm) may connect no more than two cooling holes. | Remove the engine in less than 30 cycles. |
| | Crack longer than 0.115 in. (2.921 mm) may connect no more than two cooling holes. | Remove the engine in less than 10 cycles. |
| | Crack longer than 0.120 in. (3.048 mm) may connect no more than two cooling holes. | Remove the engine in less than five cycles. |
| | Cracks connecting three or more cooling holes or closed-loop cracks through to base metal are observable. | Remove the engine in less than five cycles. |
| | Crack extends from burned area and is 0.100 in. (2.540 mm) or less in length (combination of burn and crack). | Permitted for regular inspection interval limit. |
| | Crack extends from burned area and is longer than 0.100 in. (2.540 mm) in length (combination of burn and crack). | Permitted for reduced inspection interval limit. |
| | Crack extends from burned area and is longer than 0.105 in. (2.667 mm) in length (combination of burn and crack). | Permitted for additional reduced inspection interval limit. |
| | Crack extends from burned area and is longer than 0.110 in. (2.794 mm) in length (combination of burn and crack). | Remove the engine in less than 30 cycles. |
| | Crack extends from burned area and is longer than 0.115 in. (2.921 mm) in length (combination of burn and crack). | Remove the engine in less than 10 cycles. |
| | Crack extends from burned area and is greater than or equal to 0.120 in. (3.048 mm) in length (combination of burn and crack). | Remove the engine in less than five cycles. |
| Nicks and dents | Nick or dent that has a diameter of 0.100 in. (2.540 mm) or less and with the dent depth less than 0.040 in. (1.016 mm) | Permitted for regular inspection interval limit. |
| | Nick or dent that has a diameter more than 0.100 in. (2.540 mm) or the dent depth exceeds 0.040 in. (1.016 mm). | Permitted for reduced inspection interval limit. |
| | Nick or dent that has a diameter more than 0.105 in. (2.667 mm) or the dent depth exceeds 0.045 in. (1.143 mm). | Permitted for additional reduced inspection interval limit. |
| | Nick or dent that has a diameter more than 0.110 in. (2.794 mm) or the dent depth exceeds 0.050 in. (1.270 mm). | Remove the engine in less than 30 cycles. |
| | Nick or dent that has a diameter more than 0.115 in. (2.921 mm) or the dent depth exceeds 0.055 in. (1.397 mm). | Remove the engine in less than 10 cycles. |
| | Nick or dent that has a diameter more than or equal to 0.120 in. (3.048 mm) or the dent depth exceeds 0.060 in. (1.524 mm). | Remove the engine in five cycles or less. |
| | Crack extends from a nick or dent is 0.100 in. (2.540 mm) or less (combination of a nick or dent and crack). | Permitted for regular inspection interval limit. |
| | Crack extends from a nick or dent is longer than 0.100 in. (2.540 mm) (combination of a nick or dent and crack). | Permitted for reduced inspection interval limit. |
| | Crack extends from a nick or dent is longer than 0.105 in. (2.667 mm) (combination of a nick or dent and crack). | Permitted for additional reduced inspection interval limit. |
| | Crack extends from a nick or dent is longer than 0.110 in. (2.794 mm) (combination of a nick or dent and crack). | Remove the engine in less than 30 cycles. |
| | Crack extends from a nick or dent is longer than 0.115 in. (2.921 mm) (combination of a nick or dent and crack). | Remove the engine in less than 10 cycles. |
| | Crack extends from a nick or dent is longer than 0.120 in. (3.048 mm) (combination of a nick or dent and crack). | Remove the engine in less than five cycles. |
| | Nick or dent shows signs of torn metal. | Remove the engine in less than 10 cycles. |
| | Nick or dent causes internal areas to show. | Remove the engine in less than 10 cycles. |
| Missing, chipped or flaked coating | All quantities | Permitted for regular inspection interval limit. |
| Area B for: | | |
| Oxidation and erosion | All quantities of burning, erosion or surface discoloration provided no monitorable change in surface profile (missing blade material). | Permitted for regular inspection interval limit. |
| | Burning or erosion of the base material of the blade that results in a monitorable change in surface profile (missing base material). | Permitted for reduced inspection interval limit. |
| | All quantities of burning, erosion or surface discoloration, that results in burn through to internal cavity. | Remove the engine in less than 10 cycles. |
| Blocked cooling holes | Blocked cooling holes on the leading edge are not permitted. | Permitted for reduced inspection interval limit. |
| Cracks | Crack 0.045 in. (1.143 mm) or less. May connect no more than two cooling holes. | Permitted for regular inspection interval limit. |
| | Crack longer than 0.045 in. (1.143 mm). May connect no more than two cooling holes. | Permitted for reduced inspection interval limit. |
| | Crack longer than 0.050 in. (1.270 mm). May connect no more than two cooling holes. | Permitted for additional reduced inspection interval limit. |
| | Crack longer than 0.055 in. (1.397 mm). May connect no more than two cooling holes. | Remove the engine in less than 30 cycles. |
| | Crack longer than 0.060 in. (1.524 mm). May connect no more than two cooling holes. | Remove the engine in less than 10 cycles. |
| | Crack longer than 0.065 in. (1.651 mm) or connecting three or more cooling holes or closed-loop cracks through to base metal are observable. | Remove the engine in less than five cycles. |
| | Crack extends from burned area and is 0.045 in. (1.143 mm) or less in length (combination of burn and crack). | Permitted for regular inspection interval limit. |
| | Crack extends from burned area and is longer than 0.045 in. (1.143 mm) in length (combination of burn and crack). | Permitted for reduced inspection interval limit. |
| | Crack extends from burned area and is longer than 0.050 in. (1.270 mm) in length (combination of burn and crack). | Permitted for additional reduced inspection interval limit. |
| | Crack extends from burned area and is longer than 0.055 in. (1.397 mm) in length (combination of burn and crack). | Remove the engine in less than 30 cycles. |
| | Crack extends from burned area and is longer than 0.060 in. (1.524 mm) in length (combination of burn and crack). | Remove the engine in less than 10 cycles. |
| | Crack extends from burned area and is equal to or longer than 0.065 in. (1.651 mm) in length (combination of burn and crack). | Remove the engine in less than five cycles. |
| Nicks and dents | Nick or dent that has a diameter of 0.045 in. (1.143 mm) or less and with the dent depth less than 0.020 in. (0.508 mm). | Permitted for regular inspection interval limit. |
| | Nick or dent that has a diameter more than 0.045 in. (1.143 mm) or the dent depth exceeds 0.020 in. (0.508 mm). | Permitted for reduced inspection interval limit. |
| | Nick or dent that has a diameter more than 0.050 in. (1.270 mm) or the dent depth exceeds 0.025 in. (0.635 mm). | Permitted for additional reduced inspection interval limit. |
| | Nick or dent that has a diameter more than 0.055 in. (1.397 mm) or the dent depth exceeds 0.030 in. (0.762 mm). | Remove the engine in less than 30 cycles. |
| | Nick or dent that has a diameter more than 0.060 in. (1.524 mm) or the dent depth exceeds 0.035 in. (0.889 mm). | Remove the engine in less than 10 cycles. |
| | Nick or dent that has a diameter more than or equal to 0.065 in. (1.651 mm) or the dent depth exceeds 0.040 in. (1.016 mm). | Remove the engine in less than five cycles. |
| | Crack extends from nick or dent is 0.045 in. (1.143 mm) or less (combination of nick or dent and crack). | Permitted for regular inspection interval limit. |
| | Crack extends from nick or dent is longer than 0.045 in. (1.143 mm) (combination of nick or dent and crack). | Permitted for reduced inspection interval limit. |
| | Crack extends from nick or dent is longer than 0.050 in. (1.270 mm) (combination of nick or dent and crack). | Permitted for additional reduced inspection interval limit. |
| | Crack extends from nick or dent is longer than 0.055 in. (1.397 mm) (combination of nick or dent and crack). | Remove the engine in less than 30 cycles. |
| | Crack extends from nick or dent is longer than 0.060 in. (1.524 mm) (combination of nick or dent and crack). | Remove the engine in less than 10 cycles. |
| | Crack extends from nick or dent is longer than 0.065 in. (1.651 mm) (combination of nick or dent and crack). | Remove the engine in less than five cycles. |
| | Nick or dent shows signs of torn metal. | Remove the engine in less than 10 cycles. |
| | Nick or dent causes internal areas to show. | Remove the engine in less than 10 cycles. |
| Missing, chipped or flaked coating | All quantities | Permitted for regular inspection interval limit. |
| Area C for: | | |
| Cracks | All monitorable cracks | Remove the engine in less than five cycles. |
| Nicks and dents | All monitorable nicks or dents | Remove the engine in less than five cycles. |
| Missing, chipped or flaked coating | Up to 25 percent of surface area may have missing or chipped coating. | Permitted for regular inspection interval limit. |
| | More than 25 percent of surface area may have missing or chipped coating. | Contact Pratt & Whitney. |
| Oxidation and erosion | All quantities of burning, erosion or surface discoloration are permitted if there is no missing blade material. | Permitted for additional reduced inspection interval limit. |
| | Burning or erosion of the base material of the blade that causes missing base material. | Remove the engine in less than 10 cycles. |
| | All quantities of burning, erosion or surface discoloration that cause burn through to the internal cavity. | Remove the engine in less than five cycles. |
| Area D for: | | |
| Cracks | Crack 0.050 in. (1.270 mm) or less | Permitted for regular inspection interval limit. |
| | Crack longer than 0.050 in. (1.270 mm) | Permitted for reduced inspection interval limit. |
| | Crack longer than 0.055 in. (1.397 mm) | Permitted for additional reduced inspection interval limit. |
| | Crack longer than 0.060 in. (1.524 mm) | Remove the engine in less than 30 cycles. |
| | Crack longer than 0.065 in. (1.651 mm) | Remove the engine in less than 10 cycles. |
| | Crack is greater than or equal to 0.070 in. (1.778 mm). | Remove the engine in less than five cycles. |
| Oxidation and erosion | All quantities of burning, erosion or surface discoloration are permitted if there is no missing blade material. | Permitted for additional reduced inspection interval limit. |
| | Burning or erosion of the base material of the blade that causes missing base material. | Remove the engine in less than 10 cycles. |
| | All quantities of burning, erosion or surface discoloration that cause burn through to the internal cavity. | Remove the engine in less than five cycles. |
| Nicks and dents | Nick or dent that has a diameter 0.050 in. (1.270 mm) or less or with dent depth less than 0.020 in. (0.508 mm). | Permitted for regular inspection interval limit. |
| | Nick or dent that has a diameter more than 0.050 in. (1.270 mm) or the dent depth exceeds 0.020 in. (0.508 mm). | Permitted for reduced inspection interval limit. |
| | Nick or dent that has a diameter more than 0.055 in. (1.397 mm) or the dent depth exceeds 0.025 in. (0.635 mm). | Permitted for additional reduced inspection interval limit. |
| | Nick or dent that has a diameter more than 0.060 in. (1.524 mm) or the dent depth exceeds 0.030 in. (0.762 mm). | Remove the engine in less than 30 cycles. |
| | Nick or dent that has a diameter more than 0.065 in. (1.651 mm) or the dent depth exceeds 0.035 in. (0.889 mm). | Remove the engine in less than 10 cycles. |
| | Nick or dent that has a diameter more than 0.070 in. (1.778 mm) and with the dent depth larger than 0.040 in. (1.016 mm). | Remove the engine in less than five cycles. |
| | Crack extends from a nick or dent is 0.050 in. (1.270 mm) or less (combination of a nick or dent and crack). | Permitted for regular inspection interval limit. |
| | Crack extends from a nick or dent is longer than 0.050 in. (1.270 mm) (combination of a nick or dent and crack). | Permitted for reduced inspection interval limit. |
| | Crack extends from a nick or dent is longer than 0.055 in. (1.397 mm) (combination of a nick or dent and crack). | Permitted for additional reduced inspection interval limit. |
| | Crack extends from a nick or dent is longer than 0.060 in. (1.524 mm) (combination of a nick or dent and crack). | Remove the engine in less than 30 cycles. |
| | Crack extends from a nick or dent is longer than 0.065 in. (1.651 mm) (combination of a nick or dent and crack). | Remove the engine in less than 10 cycles. |
| | Crack extends from a nick or dent is longer than 0.070 in. (1.778 mm) (combination of a nick or dent and crack). | Remove the engine in less than five cycles. |
| | Nick or dent shows signs of torn metal. | Remove the engine in less than 10 cycles. |
| | Nick or dent causes internal areas to show. | Remove the engine in less than 10 cycles. |
| Area E for: | | |
| Oxidation and erosion | All quantities of burning, erosion or surface discoloration are permitted if there is no missing blade material. | Permitted for additional reduced inspection interval limit. |
| | Burning or erosion of the base material of the blade that causes missing base material. | Remove the engine in less than 10 cycles. |
| | All quantities of burning, erosion or surface discoloration that cause burn through to the internal cavity. | Remove the engine in less than five cycles. |
| Cracks | Crack 0.070 in. (1.778 mm) or less | Permitted for regular inspection interval limit. |
| | Crack longer than 0.070 in. (1.778 mm) | Permitted for reduced inspection interval limit. |
| | Crack longer than 0.075 in. (1.905 mm) | Permitted for additional reduced inspection interval limit. |
| | Crack longer than 0.080 in. (2.032 mm) | Remove the engine in less than 30 cycles. |
| | Crack longer than 0.085 in. (2.159 mm) | Remove the engine in less than 10 cycles. |
| | Crack is equal to or longer than 0.090 in. (2.286 mm). | Remove the engine in less than five cycles. |
| Nicks and dents | Nick or dent that has a diameter 0.070 in. (1.778 mm) or less or the dent depth less than 0.020 in. (0.508 mm). | Permitted for regular inspection interval limit. |
| | Nick or dent that has a diameter more than 0.070 in. (1.778 mm) or the dent depth exceeds 0.020 in. (0.508 mm). | Permitted for reduced inspection interval limit. |
| | Nick or dent that has a diameter more than 0.075 in. (1.905 mm) or the dent depth exceeds 0.025 in. (0.635 mm). | Permitted for additional reduced inspection interval limit. |
| | Nick or dent that has a diameter more than 0.080 in. (2.032 mm) or the dent depth exceeds 0.030 in. (0.762 mm). | Remove the engine in less than 30 cycles. |
| | Nick or dent that has a diameter more than 0.085 in. (2.159 mm) or the dent depth exceeds 0.035 in. (0.889 mm). | Remove the engine in less than 10 cycles. |
| | Nick or dent that has a diameter more than 0.090 in. (2.286 mm) or the dent depth exceeds 0.040 in. (1.016 mm). | Remove the engine in less than five cycles. |
| | Crack extends from a nick or dent is 0.070 in. (1.778 mm) or less (combination of a nick or dent and crack). | Permitted for regular inspection interval limit. |
| | Crack extends from a nick or dent is longer than 0.070 in. (1.778 mm) (combination of a nick or dent and crack). | Permitted for reduced inspection interval limit. |
| | Crack extends from a nick or dent is longer than 0.075 in. (1.905 mm) (combination of a nick or dent and crack). | Permitted for additional reduced inspection interval limit. |
| | Crack extends from a nick or dent is longer than 0.080 in. (2.032 mm) (combination of a nick or dent and crack). | Remove the engine in less than 30 cycles. |
| | Crack extends from a nick or dent is longer than 0.085 in. (2.159 mm) (combination of a nick or dent and crack). | Remove the engine in less than 10 cycles. |
| | Crack extends from a nick or dent is longer than 0.090 in. (2.286 mm) (combination of a nick or dent and crack). | Remove the engine in less than five cycles. |
| | Nick or dent shows signs of torn metal. | Remove the engine in less than 10 cycles. |
| | Nick or dent causes internal areas to show. | Remove the engine in less than 10 cycles. |
| Missing, chipped or flaked coating | All quantities | Permitted for regular inspection interval limit. |
| Area F for: | | |
| Cracks | All monitorable cracks | Remove the engine in less than five cycles. |
| Oxidation and erosion | Tip oxidation is permitted, oxidation that exposes internal cavity is not permitted. | Remove the engine in less than 10 cycles. |
| For flame out only: Heavy base metal rub or open area that extends to, or more than the blade concave side cooling hole tip TSM 71-00-00-810-853 and TSM 71-00-00-810-871. | Not permitted | Remove the engine in five cycles. |
| Area G for: | | |
| Oxidation and erosion | All quantities | Remove the engine in less than 10 cycles. |
| Cracks | All monitorable cracks (or combination of a crack and a burn) not originating from the platform edge. | Remove the engine in less than five cycles. |
| Nicks and dents | All monitorable nicks or dents (or combination of a nick or dent and a burn) not originating from the platform edge. | Remove the engine in less than five cycles. |
| Missing, chipped or flaked coating | All quantities | Permitted for regular inspection interval limit. |
| Area H for: | | |
| Cracks | All monitorable cracks (or combination of a crack and a burn). | Remove the engine in less than five cycles. |
| Missing, chipped or flaked coating | All quantities | Permitted for regular inspection interval limit. |
| Oxidation and erosion | Discoloration and/or surface oxidation is only permitted at aft the platform corner. Other areas of oxidation are not permitted. | Remove the engine in less than 10 cycles. |
(12) Remove the PWA110187 KIT CONTROL or the manual wrench from the main-gearbox drive adapter and install the main-gearbox manual crank-cover (Ref. AMM TASK 72-00-00-000-805).
(13) Remove the high (N2) rotor-turning equipment (Ref. AMM TASK 72-00-00-000-805).
(14) Install the borescope plugs (Ref. AMM TASK 72-00-00-400-804).
(15) Examine the assembly for foreign objects, damage and correct assembly.
(16) Installation of the protection covers:
CAUTION:
INSTALL PROTECTION COVERS ON ALL THE OPENINGS IMMEDIATELY TO PREVENT DAMAGE TO THE ENGINE.
(a) Make sure that you install all the necessary COVER - PROTECTION to prevent damage to the engine. Subtask 72-51-00-410-058-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 72-51-00-440-053-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 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.
B. Do the reactivation of the thrust reverser system after maintenance (Ref. AMM TASK 78-30-00-440-805).
Subtask 72-51-00-410-059-A ** ON A/C NOT FOR ALL