Borescope Inspection of the Stage 2 High Pressure Turbine (HPT) Blades and Duct Segments [IAE]

TASK 72-00-00-200-015-B
Borescope Inspection of the Stage 2 High Pressure Turbine (HPT) Blades and Duct Segments

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

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

CAUTION: THE LIMITS WHICH FOLLOW ARE APPLICABLE ON A CONTINUE IN SERVICE BASIS ONLY. EACH LIMIT IS BASED ON WHAT THE STRUCTURE OF THE BLADE MUST BE AND DOES NOT INDICATE THAT THERE WILL NOT BE DETERIORATION OF THE ENGINE PERFORMANCE, STABILITY, OPERATING LIMITS OR PART REPAIRABILITY.

ZONE: 400
FIN: 1000EM1 ** ON A/C NOT FOR ALL
FIN: 1000EM2 ** ON A/C NOT FOR ALL

1. Reason for the Job
This task gives the procedure for the borescope inspection of the stage 2 HPT blades and duct segments.

NOTE: If damage is not listed contact your IAE representative.

2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	BORESCOPE - RIGHT ANGLE, FLEXSCOPE
No specific	1	BORESCOPE - RIGID
No specific	AR	COVER - EYE
No specific	AR	WARNING NOTICE(S)
No specific	Torque wrench: range to between 72 and 62 lbf.in (0.81 and 0.70 m.daN )
No specific	Torque wrench: range to between 85 and 75 lbf.in (0.96 and 0.85 m.daN )
IAE1P16184	1	PULLER, KNOCKER

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.V02-141)	corrosion resistant steel lockwire
(Material No.V10-094)	anti-seize compound
(Material No.V10-129)	anti-seize paste

C. Work Zones and Access Panels

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

D. Expendable Parts

FIG.ITEM	DESIGNATION	IPC-CSN
3	GASKET, OPTION	AIPC 72-45-00-80-040

E. Referenced Information

REFERENCE	DESIGNATION
TASK 70-23-11-911-013-A	General Torque Tightening Techniques
TASK 71-13-00-010-010-A	Opening of the Fan Cowls 437AL(447AL),438AR(448AR)
TASK 71-13-00-410-010-A	Closing of the Fan Cowls 437AL(447AL),438AR(448AR)
TASK 72-00-00-080-010-A	Removal of the Rotator Kit for Borescope Inspection
TASK 72-00-00-480-010-A	Installation of the Rotator Kit for Borescope Inspection
TASK 72-00-00-860-010-A	Rotation of the HP Compressor with the Hand Turning Tool
TASK 78-30-00-040-012-A	Deactivation of the Thrust Reverser Hydraulic Control Unit (HCU) for Ground Maintenance
TASK 78-30-00-440-012-A	Re-activation of the Thrust Reverser Hydraulic Control Unit (HCU) after Ground Maintenance
TASK 78-32-00-010-010-A	Opening of the Thrust Reverser Halves
TASK 78-32-00-410-010-A	Closing of the Thrust Reverser Halves
EM 724532
Crank Pad Location
Stage 2 HPT Blade Inspection Areas
Stage 2 HPT blade inspection Areas
HP Turbine Borescope Locations for Inspection of the Stage 2 HPT Blades (Left Side)
HP Turbine Borescope Ports for Inspection of the Stage 2 HPT Blades (Right Side)
Borescope Ports
HP and LP Turbine Ports for Inspection of the Stage 2 HPT Blades
Stage 2 HPT Blade Inspection Areas
Stage 2 HPT Duct Segment Inspection Locations

3. Job Set-up
Subtask 72-00-00-941-091-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) On the center pedestal, on the ENG panel 115VU:
(a) Put a WARNING NOTICE(S) to tell persons not to start the engine.
(2) Make sure that the engine 1(2) shutdown occurred not less than 5 minutes before you do this procedure.
(3) On the overhead maintenance panel 50VU:
(a) Make sure that the ON legend of the ENG/FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put a WARNING NOTICE(S) to tell persons not to energize the FADEC 1(2).

Subtask 72-00-00-010-119-A ** ON A/C NOT FOR ALL

B. Open the fan cowls (Ref. AMM TASK 71-13-00-010-010):
(1) FOR [1000EM1] (ENGINE-1)
437AL 438AR.
(2) FOR [1000EM2] (ENGINE-2)
447AL 448AR.

Subtask 72-00-00-040-078-A ** ON A/C NOT FOR ALL

C. Deactivate the thrust reverser:

WARNING: MAKE SURE THAT THE THRUST REVERSER HYDRAULIC CONTROL UNIT (HCU) IS DEACTIVATED BEFORE YOU DO WORK ON OR AROUND THE THRUST REVERSER. IF THE HCU IS NOT DEACTIVATED, THERE IS A RISK OF UNWANTED THRUST REVERSER OPERATION WHICH CAN CAUSE INJURY TO PERSONS AND/OR DAMAGE TO EQUIPMENT.

(1) Deactivate the thrust reverser hydraulic control unit (HCU) (Ref. AMM TASK 78-30-00-040-012).

Subtask 72-00-00-010-127-A ** ON A/C NOT FOR ALL

D. Open the thrust reverser halves (Ref. AMM TASK 78-32-00-010-010):
(1) FOR [1000EM1] (ENGINE-1)
451AL 452AR.
(2) FOR [1000EM2] (ENGINE-2)
461AL 462AR.

Subtask 72-00-00-480-065-A ** ON A/C NOT FOR ALL

E. Install the foot operated motor drive unit to the gearbox crank pad (1)

Crank Pad Location ** ON A/C NOT FOR ALL

(Ref. AMM TASK 72-00-00-480-010).

NOTE: With this unit the rotor can be turned 360 degrees to permit complete inspection.

(1) If the foot-operated motor drive is unavailable for use, rotate the HP compressor with the hand turning tool (Ref. AMM TASK 72-00-00-860-010).

4. Procedure
Subtask 72-00-00-290-075-A ** ON A/C NOT FOR ALL

A. General

CAUTION: THE ENGINE IS HOT IMMEDIATELY AFTER SHUTDOWN AND CAN CAUSE BURNS AND DAMAGE TO THE BORESCOPE EQUIPMENT. WAIT 2-3 HOURS AFTER SHUTDOWN BEFORE YOU DO A BORESCOPE INSPECTION.

(1) The names of the different parts, areas and dimensional references of the Stage 2 HPT blades are shown.

Stage 2 HPT Blade Inspection Areas ** ON A/C NOT FOR ALL

Stage 2 HPT blade inspection Areas ** ON A/C NOT FOR ALL

(2) Use the names which follow when you identify a blade condition seen during borescope inspection:
(a) Erosion: A smooth area at the tip that shows material is gone.
(b) Leading Edge Burn-Through : A hole in the leading edge open to the cooling air passage.
(c) Burns: A local area that is rough, not the initial color, or where there is no material.
(d) Nick or dent: A damage area that can be smooth, have cracks, a hole that is open to the cooling air passages or have holes and cracks.
(e) Coating damage: Chipping, flaking, blistering, peeling or oxidation of blade confined to coating.

Subtask 72-00-00-010-120-A ** ON A/C NOT FOR ALL

WARNING: MAKE SURE THAT THE BLANKING PLUG IS SUFFICIENTLY COOL BEFORE REMOVAL. THE TEMPERATURE STAYS HIGH FOR A SHORT TIME AFTER ENGINE SHUTDOWN.

CAUTION: MAKE SURE THAT THE SLEEVE FLANGED BUSHING DOES NOT FALL OUT. IF THE PART FALLS IT WILL BE DAMAGED.

B. Get access to the Stage 2 HPT blades through the T1/2L or T1/2R or T2/3L or T2/3R ports

HP Turbine Borescope Locations for Inspection of the Stage 2 HPT Blades (Left Side) ** ON A/C NOT FOR ALL

HP Turbine Borescope Ports for Inspection of the Stage 2 HPT Blades (Right Side) ** ON A/C NOT FOR ALL

Borescope Ports ** ON A/C NOT FOR ALL

NOTE: If you remove the blanking plugs at both locations, you will be able to examine the leading and trailing edges.

(1) Remove the T1/2L or T1/2R access ports
(a) Release the wire that safeties the bolts.
(b) Remove the bolts.
(c) Install the IAE1P16184 PULLER, KNOCKER to the center hole of the plug (use if required).
(d) Use the puller to remove the blanking plug from the port.
(e) Remove the gasket from the plug and the plug from the puller.
(2) Remove the T2/3L or T2/3R access ports
(a) Release the wire that safeties the bolts.
(b) Remove the bolts.
(c) Remove the blanking plug and spacer plates.

NOTE: Do not change the spacer plates as they are adjusted to the related blanking plug.

(d) Remove the sleeve flanged bushing.

Subtask 72-00-00-290-076-A ** ON A/C NOT FOR ALL

C. Do a borescope inspection of the Stage 2 HPT blades

Stage 2 HPT Blade Inspection Areas ** ON A/C NOT FOR ALL

Stage 2 HPT blade inspection Areas ** ON A/C NOT FOR ALL

NOTE: A COVER - EYE on the eye that is not used will decrease eye tension.

NOTE: The borescope inspection of the Stage 2 HPT blades and duct segments shows areas of the Stage 2 nozzle guide vane. If you find damage on the Stage 2 nozzle guide vanes, contact your IAE representative.

(1) Put the BORESCOPE - RIGHT ANGLE, FLEXSCOPE through the T1/2L or T1/2R port.

HP and LP Turbine Ports for Inspection of the Stage 2 HPT Blades ** ON A/C NOT FOR ALL

(2) Examine the blades for damage.
(3) Put the BORESCOPE - RIGHT ANGLE, FLEXSCOPE through the T1/2L or T1/2R port.

HP and LP Turbine Ports for Inspection of the Stage 2 HPT Blades ** ON A/C NOT FOR ALL

(4) Examine the blades for damage on the concave and convex sides from the leading edge rearward.
(5) Put the BORESCOPE - RIGID through the T2/3L or T2/3R port.

HP and LP Turbine Ports for Inspection of the Stage 2 HPT Blades ** ON A/C NOT FOR ALL

(6) Examine the blades for damage.

Subtask 72-00-00-220-194-A ** ON A/C NOT FOR ALL

D. Examine the Stage 2 Nozzle Guide-Vane
(1) The table below applies to the stage 2 nozzle guide-vane condition observed when doing a stage 2 HPT borescope inspection.

CONDITION	AMOUNT	DISPOSITION
1. Cracks and chipped coating	Any amount.	Acceptable.
2. Inner or outer platform burn-through holes	Burn-through hole 0.25 in. (6.35 mm) by 0.050 in. (1.27 mm) – 3 locations maximum.	Acceptable.
Burn-through hole greater than 0.25 in. (6.35 mm) by 0.050 in. (1.27 mm).	Remove the engine in less than 30 cycles.
3. Leading-edge burn-through holes	Less than 0.050 in. (1.27 mm) radially.	Acceptable.
Between 0.050 in. (1.27 mm) and 0.300 in. (7.62 mm) radially, no impingement rib damage permitted.	Do the inspection again at 300 flight hour intervals.
Greater than 0.300 in. (7.62 mm) radially, no impingement rib damage permitted.	Remove the engine in less than 10 cycles.
4. Conditions other than 1, 2 or 3 above	Any.	Contact IAE.

Subtask 72-00-00-220-102-A ** ON A/C NOT FOR ALL

E. Nicks, dents and holes on the airfoil of the stage 2 HPT blades

Stage 2 HPT Blade Inspection Areas ** ON A/C NOT FOR ALL

Stage 2 HPT blade inspection Areas ** ON A/C NOT FOR ALL

Stage 2 HPT Blade Inspection Areas ** ON A/C NOT FOR ALL

Time/Cycle Limits Interval	Area A	Area B	Area C	Area D	Area TE
600 Hours		The nick or dent has cracks and the total length of the nick or dent plus the cracks is less than 0.150 in. (3.81 mm) long axially or less than 0.180 in. (4.57 mm) long radially.	The nick or dent has cracks and the total length of the nick or dent plus the cracks is less than 0.150 in. (3.81 mm) long axially or less than 0.180 in. (4.57 mm) long radially.
600 Hours		The nick or dent has a hole or a hole with cracks and the total length of the nick or dent plus the hole or hole with a crack is less than 0.100 in. (2.54 mm) long axially or less than 0.180 in. (4.57 mm) long radially.	The nick or dent has a hole or a hole with cracks and the total length of the nick or dent plus the hole or hole with a crack is less than 0.100 in. (2.54 mm) long axially or less than 0.180 in. (4.57 mm) long radially.
600 Hours		The hole is less than 0.040 in. (1.02 mm) long axially and less than 0.050 in. (1.27 mm) long radially.	The hole is less than 0.040 in. (1.02 mm) long axially and less than 0.050 in. (1.27 mm) long radially.
300 Hours	The nick or dent has cracks, a hole or a hole with cracks and the total length of the nick or dent plus the crack is less than 0.120 in. (3.05 mm) long axially or less than 0.140 in. (3.56 mm) long radially.	The nick or dent has cracks, a hole or a hole with cracks and the total length of the nick or dent plus the crack is between 0.150 in. (3.81 mm) and 0.200 in. (5.08 mm) long axially or between 0.180 in. (4.57 mm) and 0.450 in. (11.43 mm) long radially.	The nick or dent has cracks, a hole or a hole with cracks and the total length of the nick or dent plus the crack is between 0.150 in. (3.81 mm) and 0.250 in. (6.35 mm) long axially or between 0.180 in. (4.57 mm) and 0.450 in. (11.43 mm) long radially.	There is a nick.
300 Hours		The hole is between 0.040 in. (1.02 mm) and 0.080 in. (2.03 mm) long axially or is between 0.050 in. (1.27 mm) and 0.100 in. (2.54 mm) long radially.	The hole is between 0.040 in. (1.02 mm) and 0.080 in. (2.03 mm) long axially or is between 0.050 in. (1.27 mm) and 0.100 in. (2.54 mm) long radially.	There is a dent with a depth greater than 0.015 in. (0.38 mm) or the dent does not have a smooth bottom.
150 Hours
Remove the engine in less than 30 cycles.
Remove the engine in less than 10 cycles.	The nick or dent has cracks, a hole or a hole with cracks and the total length of the nick or dent plus the crack is more than 0.120 in. (3.05 mm) long axially or more than 0.140 in. (3.56 mm) long radially.	The nick or dent has cracks, a hole or a hole with cracks and the total length of the nick or dent plus the crack is more than 0.200 in. (5.08 mm) long axially or more than 0.450 in. (11.43 mm) long radially.	The nick or dent has cracks, a hole or a hole with cracks and the total length of the nick or dent plus the crack is more than 0.250 in. (6.35 mm) long axially or more than 0.450 in. (11.43 mm) long radially.	There is a nick or dent with signs of burns, torn metal or cracks.	The nick or dent is in the trailing edge of area D and has a depth greater than 0.005 in. (0.13 mm) or does not have a smooth bottom.
Remove the engine in less than 10 cycles.	There is a hole larger than 0.080 in. (2.03 mm) axially or 0.100 in. (2.54 mm) radially.	There is a hole larger than 0.080 in. (2.03 mm) axially or 0.100 in. (2.54 mm) radially.	There is a hole larger than 0.080 in. (2.03 mm) axially or 0.100 in. (2.54 mm) radially.	There is a hole.
Remove the engine in less than 10 cycles.	There is more than one hole.	There is more than one hole.	There is more than one hole.	There is more than one hole.	There is more than one hole.

NOTE: The trailing edge of the stage 2 HPT blade can be blended per EM 724532. Blends on the trailing edge of the blade will be smooth and round bottomed and made in the shape of the initial contour. Blades that have been blended in accordance with VRS3240 are acceptable and can continue on in service.

NOTE: Manufacturers holes are not included.

NOTE: Axial tip cracks may have the potential of releasing the blade tip, which may cause minor gaspath downstream damage.

NOTE: The most restrictive limits apply.

NOTE: There may be excess material in the form of small bumps on the airfoil. This is a result of the casting procedure. During borescope inspection, these small bumps may be noticed on the concave and convex surfaces of the airfoil. These bumps are usually round or oval shaped with a height of 0.002 in. (0.0508 mm) to 0.005 in. (0.1270 mm) depending on airfoil location. These bumps are acceptable and do not require dimensional inspection.

Subtask 72-00-00-220-103-A ** ON A/C NOT FOR ALL

F. Erosion or burns on the airfoil or platform of the Stage 2 HPT blades

Stage 2 HPT Blade Inspection Areas ** ON A/C NOT FOR ALL

Stage 2 HPT blade inspection Areas ** ON A/C NOT FOR ALL

Stage 2 HPT Blade Inspection Areas ** ON A/C NOT FOR ALL

Time/ Cycle Limits Interval	Area A	Area B	Area C	Area D	Area TE	Area Platform
600 Hours					The erosion or burn is on the airfoil trailing edge in Area D.
600 Hours					The erosion or burn is on the airfoil trailing edge in Area C and is longer than 0.100 in. (2.54 mm) long axially or 0.200 in. (5.08 mm) long radially.
600 Hours	The erosion or burn is on the leading edge and extends more than one-quarter of the airfoil radial length.	The erosion or burn is on the leading edge and extends more than one-quarter of the airfoil radial length.	The erosion or burn is on the leading edge and extends more than one-quarter of the airfoil radial length.			The erosion or burn on the platform has gone through the coating.
600 Hours	The erosion or burn on the leading edge has changed the shape of the airfoil.	The erosion or burn on the leading edge has changed the shape of the airfoil.	The erosion or burn on the leading edge has changed the shape of the airfoil.
600 Hours	The erosion or burn on the airfoil has gone through the coating. This does not include burns on the leading edge.	The erosion or burn on the airfoil has gone through the coating. This does not include burns on the leading edge.	The erosion or burn on the airfoil has gone through the coating. This does not include burns on the leading edge.	The erosion or burn on the airfoil has gone through the coating. This does not include burns on the leading edge.	The erosion or burn on the airfoil has gone through the coating. This does not include burns on the leading edge.
300 Hours
150 Hours
Remove the engine in less than 30 cycles.
Remove the engine in less than 10 cycles.					The erosion or burn is in Area C and is more than 0.250 in. (6.35 mm) long axially.
Remove the engine in less than 10 cycles.					The erosion or burn is in Area D and is more than 0.050 in. (1.27 mm) long radially.
Remove the engine in less than 10 cycles.						The burn on the platform increases the gap with the adjacent blade platform to more than 0.050 in. (1.27 mm).
Remove the engine in less than 10 cycles.						The burn on the platform goes into the airfoil fillet radius.
Remove the engine in less than 10 cycles.	The erosion or burn has an adjacent area which shows signs of cracks.	The erosion or burn has an adjacent area which shows signs of cracks.	The erosion or burn has an adjacent area which shows signs of cracks.	The erosion or burn has an adjacent area which shows signs of cracks.	The erosion or burn has an adjacent area which shows signs of cracks.	The erosion or burn has an adjacent area which shows signs of cracks.
Remove the engine in less than 10 cycles.	The erosion or burn on the airfoil or platform permits internal areas to show, the internal areas are where air goes that is used to cool the blade.	The erosion or burn on the airfoil or platform permits internal areas to show, the internal areas are where air goes that is used to cool the blade.	The erosion or burn on the airfoil or platform permits internal areas to show, the internal areas are where air goes that is used to cool the blade.	The erosion or burn on the airfoil or platform permits internal areas to show, the internal areas are where air goes that is used to cool the blade.	The erosion or burn on the airfoil or platform permits internal areas to show, the internal areas are where air goes that is used to cool the blade.	The erosion or burn on the airfoil or platform permits internal areas to show, the internal areas are where air goes that is used to cool the blade.
Remove the engine in less than 10 cycles.	The erosion or burn on the airfoil or platform changes the shape of the airfoil, this does not include burns on the leading edge.	The erosion or burn on the airfoil or platform changes the shape of the airfoil, this does not include burns on the leading edge.	The erosion or burn on the airfoil or platform changes the shape of the airfoil, this does not include burns on the leading edge.	The erosion or burn on the airfoil or platform changes the shape of the airfoil, this does not include burns on the leading edge.	The erosion or burn on the airfoil or platform changes the shape of the airfoil, this does not include burns on the leading edge.	The erosion or burn on the airfoil or platform changes the shape of the airfoil, this does not include burns on the leading edge.

NOTE: Manufacturers holes are not included.

NOTE: Axial tip cracks may have the potential of releasing the blade tip, which may cause minor gaspath downstream damage.

NOTE: The most restrictive limits apply.

Subtask 72-00-00-220-190-A ** ON A/C NOT FOR ALL

G. Cracks on the Airfoil of the Stage 2 HPT Blades

Stage 2 HPT Blade Inspection Areas ** ON A/C NOT FOR ALL

Stage 2 HPT blade inspection Areas ** ON A/C NOT FOR ALL

Stage 2 HPT Blade Inspection Areas ** ON A/C NOT FOR ALL

Time/ Cycle Limits Interval	Area A	Area B	Area C	Area D	Area TE
600 Hours		The crack is less than 0.080 in. (2.03 mm) long axially or less than 0.180 in. (4.57 mm) long radially.	The crack is less than 0.080 in. (2.03 mm) long axially or less than 0.180 in. (4.57 mm) long radially.		The trailing edge crack is in Area C and is less than 0.300 in. (7.62 mm) long in any direction.
300 Hours	The crack is less than 0.080 in. (2.03 mm) long axially or less than 0.140 in. (3.56 mm) long radially.	The crack is between 0.080 in. (2.03 mm) and 0.140 in. (3.56 mm) long axially or between 0.180 in. (4.57 mm) and 0.360 in. (9.14 mm) long radially.	The crack is between 0.080 in. (2.03 mm) and 0.610 in. (15.49 mm) long axially or between 0.180 in. (4.57 mm) and 0.360 in. (9.14 mm) long radially. The crack must be forward of the trailing edge slots. For these cracks, intersecting cracks are allowed if the intersection of the crack is within 0.200 in. (5.08 mm) of the blade tip. This does not include closed loop cracks or trailing edge slot cracks.
150 Hours			The crack is between 0.610 in. (15.49 mm) and 0.800 in. (20.32 mm) long axially and must be outside the trailing edge slots. The axial crack can have up to 0.450 in. (11.43 mm) in radial length. For these cracks, intersecting cracks are allowed if the intersection of the crack is within 0.200 in. (5.08 mm) of the blade tip. This does not include closed loop cracks or trailing edge slot cracks.
Remove the engine in less than 30 cycles.			There is a crack that is more than 0.800 in. (20.32 mm) long axially or more than 0.450 in. (11.43 mm) long radially.
Remove the engine in less than 10 cycles.	The crack is more than 0.080 in. (2.03 mm) long axially or more than 0.140 in. (3.56 mm) long radially.	The crack is more than 0.140 in. (3.56 mm) long axially or more than 0.360 in. (9.14 mm) long radially.			There is a trailing edge crack in Area D.
Remove the engine in less than 10 cycles.					There is a trailing edge crack in Area C and is more than 0.300 in. (7.62 mm) long in any direction.
Remove the engine in less than 10 cycles.	Cracks on the airfoil go through or touch other cracks, trailing edge slot cracks or closed loop cracks (this does not include cracks at the tip as described above).	Cracks on the airfoil go through or touch other cracks, trailing edge slot cracks or closed loop cracks (this does not include cracks at the tip as described above).	Cracks on the airfoil go through or touch other cracks, trailing edge slot cracks or closed loop cracks (this does not include cracks at the tip as described above).	Cracks on the airfoil go through or touch other cracks, trailing edge slot cracks or closed loop cracks (this does not include cracks at the tip as described above).	Cracks on the airfoil go through or touch other cracks, trailing edge slot cracks or closed loop cracks (this does not include cracks at the tip as described above).
Remove the engine in less than 10 cycles.	Loss of blade tip material so that the internal cooling cavity shows.	Loss of blade tip material so that the internal cooling cavity shows.	Loss of blade tip material so that the internal cooling cavity shows.	Loss of blade tip material so that the internal cooling cavity shows.	Loss of blade tip material so that the internal cooling cavity shows.
Remove the engine in less than 10 cycles.	Loss of trailing edge tip material above the last trailing edge cooling slot.	Loss of trailing edge tip material above the last trailing edge cooling slot.	Loss of trailing edge tip material above the last trailing edge cooling slot.	Loss of trailing edge tip material above the last trailing edge cooling slot.	Loss of trailing edge tip material above the last trailing edge cooling slot.

NOTE: Manufacturers holes are not included.

NOTE: Axial tip cracks may have the potential of releasing the blade tip, which may cause minor gaspath downstream damage.

NOTE: The most restrictive limits apply.

Subtask 72-00-00-220-150-A ** ON A/C NOT FOR ALL

H. Airfoil surface imperfection (areas of raised material) and surface imperfections with cracks.

Stage 2 HPT blade inspection Areas ** ON A/C NOT FOR ALL

Time/ Cycle Limits Interval	Area A	Area B	Area C	Area D	Area TE
600 Hours	There are surface imperfections (areas of raised material) on the airfoil surface.	There are surface imperfections (areas of raised material) on the airfoil surface.	There are surface imperfections (areas of raised material) on the airfoil surface.	There are surface imperfections (areas of raised material) on the airfoil surface.	There are surface imperfections (areas of raised material) on the airfoil surface.
600 Hours		A surface imperfection has a crack with a length that is less than 0.080 in. (2.03 mm) long axially or less than 0.180 in. (4.57 mm) long radially.	A surface imperfection has a crack with a length that is less than 0.080 in. (2.03 mm) long axially or less than 0.180 in. (4.57 mm) long radially.
300 Hours	A surface imperfection has a crack with a length that is less than 0.080 in. (2.03 mm) long axially or less than 0.140 in. (3.56 mm) long radially.	A surface imperfection has a crack with a length that is between 0.080 in. (2.03 mm) and 0.140 in. (3.56 mm) long axially or between 0.180 in. (4.57 mm) and 0.360 in. (9.14 mm) long radially.	A surface imperfection has a crack with a length that is between 0.080 in. (2.03 mm) and 0.200 in. (5.08 mm) long axially or between 0.180 in. (4.57 mm) and 0.360 in. (9.14 mm) long radially.
150 Hours
Remove the engine in less than 30 cycles.
Remove the engine in less than 10 cycles.	A surface imperfection has a crack with a length more than 0.080 in. (2.03 mm) long axially or more than 0.140 in. (3.56 mm) long radially.	A surface imperfection has a crack with a length more than 0.140 in. (3.56 mm) long axially or more than 0.360 in. (9.14 mm) long radially.	A surface imperfection has a crack with a length more than 0.200 in. (5.08 mm) long axially or more than 0.360 in. (9.14 mm) long radially.	A surface imperfection has a crack.
Remove the engine in less than 10 cycles.	Surface imperfections on the airfoil surface have cracks that go through other cracks.	Surface imperfections on the airfoil surface have cracks that go through other cracks.	Surface imperfections on the airfoil surface have cracks that go through other cracks.	Surface imperfections on the airfoil surface have cracks that go through other cracks.	Surface imperfections on the airfoil surface have cracks that go through other cracks.

NOTE: Manufacturers holes are not included.

NOTE: Axial tip cracks may have the potential of releasing the blade tip, which may cause minor gaspath downstream damage.

NOTE: The most restrictive limits apply.

Subtask 72-00-00-220-105-A ** ON A/C NOT FOR ALL

I. Cracks on the platform of the Stage 2 HPT blades

Stage 2 HPT Blade Inspection Areas ** ON A/C NOT FOR ALL

Time/Cycle Limits Interval	Area A	Area B	Area C	Area D	Area TE	Area Platform
600 Hours						Cracks that are longer than 0.125 in. (3.17 mm) that do not go through the platform to the airfoil fillet radius.
300 Hours
150 Hours
Remove the engine in less than 30 cycles.
Remove the engine in less than 10 cycles.						There is a crack which goes through the platform to airfoil fillet radius.

NOTE: Manufacturers holes are not included.

NOTE: Axial tip cracks may have the potential of releasing the blade tip, which may cause minor gaspath downstream damage.

NOTE: The most restrictive limits apply.

Subtask 72-00-00-220-107-A ** ON A/C NOT FOR ALL

J. Examine the stage 2 HPT duct segments for burn holes

Stage 2 HPT Duct Segment Inspection Locations ** ON A/C NOT FOR ALL

NOTE: When you do a borescope inspection of the Stage 2 HPT blades, some areas of the Stage 2 HPT duct segments can be seen. Locations 1 and 2 in the figure are important areas.

Stage 2 HPT Duct Segment Inspection Locations ** ON A/C NOT FOR ALL

(1) Remove the engine in less than 10 cycles if:
(a) There is burn hole that is longer than 0.5 in. (12.7 mm).

NOTE: Quantity of cracks is not important and are acceptable without reduced inspection intervals.

5. Close-up
Subtask 72-00-00-410-112-A ** ON A/C NOT FOR ALL

A. Close the borescope inspection ports after borescope inspection is completed as follows:

Borescope Ports ** ON A/C NOT FOR ALL

(1) For the T1/2L or T1/2R port, proceed as follows:
(a) Put the 72450080-040GASKET, OPTION3 in the case recess.
(b) Replace the gasket if it is not above the case surface.
(c) Installation of the plug

CAUTION: BE CAREFUL WHEN YOU INSTALL THE PLUG. IF THE PLUG BREAKS DURING THE INSTALLATION AND A PLUG PIECE FALLS INTO THE SECOND-STAGE VANE CAVITY, REMOVE THIS PIECE BEFORE YOU PUT THE ENGINE BACK INTO SERVICE. IF NECESSARY, REMOVE THE TURBINE COOLING-AIR TUBE TO GET ACCESS TO THE SECOND-STAGE VANE CAVITY. IF YOU DO NOT REMOVE THE PLUG PIECE FROM THE VANE CAVITY, DAMAGE TO THE ENGINE CAN OCCUR.

1 Put the gasket on the plug (4) and install the plug in the case.
(d) Lubricate the bolt threads with anti-seize paste (Material No.V10-129) or anti-seize compound (Material No.V10-094) . Wipe off excess paste.
1 Make sure that the borescope plug is correctly installed and bolt holes are aligned prior to continuing to next step.

NOTE: It is permissible to correct minor thread damage to a threaded hole with a 0.250-28UNJF-3B tap.

(e) Install the bolts.
(f) TORQUE the bolts to between 85 and 75 lbf.in (0.96 and 0.85 m.daN )

(Ref. AMM TASK 70-23-11-911-013).
(g) Safety the bolts with corrosion resistant steel lockwire (Material No.V02-141) .
(2) For the T2/3L or the T2/3R port, proceed as follows:

CAUTION: MAKE SURE THAT THE SLEEVE FLANGED BUSHING DOES NOT FALL OUT. IF THE PART FALLS IT WILL BE DAMAGED.

(a) Install the sleeve flanged bushing.

NOTE: Do not change the spacer plates as they are adjusted to the related blanking plug.

(b) Install the blanking plug (2) with the related spacer plates.
(c) Apply anti-seize paste (Material No.V10-129) to the bolts and install the bolts. Wipe off excess paste.
(d) TORQUE the bolts to between 72 and 62 lbf.in (0.81 and 0.70 m.daN )

(Ref. AMM TASK 70-23-11-911-013).
(e) Safety the bolts with corrosion resistant steel lockwire (Material No.V02-141) .

Subtask 72-00-00-080-060-A ** ON A/C NOT FOR ALL

B. Remove the foot operated motor drive unit from the gearbox crank pad (Ref. AMM TASK 72-00-00-080-010).

Subtask 72-00-00-410-113-A ** ON A/C NOT FOR ALL

C. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the thrust reverser halves (Ref. AMM TASK 78-32-00-410-010):
(a) FOR [1000EM1] (ENGINE-1)
451AL 452AR.
(b) FOR [1000EM2] (ENGINE-2)
461AL 462AR.

Subtask 72-00-00-440-076-A ** ON A/C NOT FOR ALL

D. Activate the thrust reverser HCU (Ref. AMM TASK 78-30-00-440-012).

Subtask 72-00-00-410-131-A ** ON A/C NOT FOR ALL

E. Close Access
(1) Close the fan cowls (Ref. AMM TASK 71-13-00-410-010):
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR.
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR.
(2) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 03:59:25 UTC