Over-Serviceable-Limit Extensions [CFMB]

TASK 72-00-00-200-025-A-01
Over-Serviceable-Limit Extensions

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.

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 is applicable to /P engines, /3 engines and /3 PIP engines.
It can occur that specific defects do not agree with the "Maximum Serviceable Limits", and that the maintenance facilities, at a given location, are not sufficient to do the necessary corrective actions.
In these circumstances, limit extensions will permit to send the engine where correction is possible, or to schedule the necessary maintenance in the extension period.

NOTE: The limit extensions are one-time extensions only. Applicable hardware action is necessary at the completion of the extended serviceable period.

2. Job Set-up Information
A. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
400	POWER PLANT, NACELLES AND PYLONS

B. Referenced Information

REFERENCE	DESIGNATION
TASK 72-21-00-210-006-A	Inspection of the Fan Rotor Blades Removed from the Fan Disk
TASK 72-21-00-210-009-A	Inspection of Fan Rotor Blades Installed on the Fan Disk
TASK 72-23-00-000-008-A	Removal of the Fan Outlet Guide Vane (OGV) Doublets
TASK 72-23-00-210-003-C	Detailed Inspection of Spinner, Engine Inlet, Fan Blades, Fan Outlet and Abradable Material
TASK 72-23-00-400-008-A	Installation of the Fan Outlet Guide Vane (OGV) Doublets
TASK 79-00-00-210-003-A	Visual Inspection of the Oil System
Booster Rotor and Stator Damage Extended
Extended Vanes Damage Limits
HPT Blade Inspection (Only Applicable to /P Engines)
Inspection/Check of the Fan Outlet Guide Vanes (OGV)
Outlet Guide Vane (OGV) Inner Platform for Cracks
Outlet Guide Vane (OGV) Inner Platform for Missing Material
Cracks and Missing Material in the Dome Area
Example of Axial Cracks, Radial Cracks and Holes on Stage 1 LPT Nozzle Segment
Airfoil with Missing Material or Full Axial Crack from LE to TE

3. Job Set-up
Subtask 72-00-00-941-105-A ** ON A/C NOT FOR ALL

A. Not applicable

4. Procedure
Subtask 72-00-00-210-101-A ** ON A/C NOT FOR ALL

A. Over-Serviceable-Limit Extensions

CONDITION			MAX. EXTENSION
1.Fan and booster
A.Spinner front cone
(1)Corrosion marks (white mushroom pattern) before part removal.			A continuation in service of 100 cycles maximum is permitted.
B.Spinner rear cone
(1)Oil wetting at inner of spinner cone or fan disk or forward fan shaft.			50 cycles
(2)Seal ring tear: any number if cumulated length is more than 0.4 in. (10.16 mm).			50 cycles
C.Fan blade
(1)Fully missing molydag on inner faces of the platforms			250 cycles
(2)Flaking of Cu.Ni.In coating on blade dovetail pressure faces (contact areas), up to 10 % if there is no indication of wear on base material.			Examine blades for serviceability (Ref. AMM TASK 72-21-00-210-006). 1200 cycles after relubrication. Repeat extension is permitted.
(3)Flaking of Cu.Ni.In coating on blade dovetail pressure faces (contact areas), more than 10 % and less than 50 % if there is no indication of wear on base material.			400 cycles after relubrication. Repeat extension is not permitted.
(4)Shingling at mid span shrouds			Turn the shingled blades to the 12 o'clock position and unshingle with hand force or by using a piece of wood. Examine blades for serviceability (Ref. AMM TASK 72-21-00-210-009). Remove and send the shingled blades to a shop for a dimensional inspection and an Fluorescent Penetrant Inspection (FPI) in less than 50 cycles.
(5)Nicks, dents, scratches and sheared edges on midspan shroud surfaces up to 0.035 in. (0.89 mm) deep if defects are not in the midspan shroud to airfoil fillet radius.			50 cycles
(6)Missing or damaged hard coating on midspan shroud pressure faces more than 20 % but less than 40 % of coated area.			50 cycles
D.Fan disk
(1)Wear greater than 50 % of area on disk dovetail pressure faces.			100 cycles
E.Booster rotor blade for:
(1)Piece missing: any number in area G, at Leading Edge (LE) and Trailing Edge (TE) tip corners, 0.8 in. (20.32 mm) radial and 0.5 in. (12.70 mm).			50 cycles or 75 hours (whichever comes first)
(2)Cracks and tears in area G, 0.8 in. (20.32 mm) from tip: any number, less than 0.8 in. (20.32 mm) radial and less than 0.492 in. (12.50 mm) axial.			50 cycles or 75 hours (whichever comes first)
(3)Wear or local distortion of TE and LE tips if less than 15 blades, 0.984 in. (24.99 mm) radial and 0.590 in. (14.99 mm) axial.			100 cycles or 150 hours (whichever comes first)
(4)Nicks, dents, scratches for area E: any number, less than 0.059 in. (1.50 mm) in diameter, protrusion acceptable, not thru.			50 cycles or 75 hours (whichever comes first)
(5)Nicks, dents, scratches for airfoil out of area E, not LE and TE: any number, less than 0.236 in. (5.99 mm) in diameter, protrusion acceptable.			50 cycles or 75 hours (whichever comes first)
(6)Nicks, dents, scratches out of area E on LE and TE: maximum axial length less than 0.059 in. (1.50 mm).			50 cycles or 75 hours (whichever comes first)
(7)Distorted LE and TE, out of area E: maximum circumference equals 0.275 in. (6.98 mm), radial length equals 0.708 in. (17.98 mm).			50 cycles or 75 hours (whichever comes first)
F.Booster vanes (stage 1 only) for:
(1)Piece missing: maximum 20 blades more than 0.256 in. (6.50 mm) axial, 0.728 in. (18.49 mm) radial, no cracks starting from damage area allowed in areas A and B.			50 cycles or 75 hours (whichever comes first)
(2)Cracks and tears in area C, any number, more than 0.526 in. (13.36 mm) radial and 0.078 in. (1.98 mm) axial. In areas A and B, any number more than 0.128 in. (3.25 mm) radial and 0.039 in. (0.99 mm) axial.			10 cycles or 15 hours (whichever comes first)
(3)Distortion of TE and LE: any number, if the length L is not more than 1 in. (25.40 mm) and the maximum dimension X along the chord width is not more than 0.492 in. (12.50 mm).			50 cycles or 75 hours (whichever comes first)
(4)Nicks, dents, scratches for areas A and B: any number, less than 0.157 in. (3.99 mm) in diameter, protrusion permitted.			10 cycles or 15 hours (whichever comes first)
(5)Nicks, dents, scratches for area C: any number, less than 0.295 in. (7.49 mm) in diameter, protrusion permitted.			50 cycles or 75 hours (whichever comes first)
(6)Nicks, dents, scratches on LE and TE: maximum axial length less than 0.118 in. (3.00 mm) in diameter.			20 cycles or 30 hours (whichever comes first)
(7)Cracked inner shroud: maximum of 4 cracks extending from the LE to the TE of the inner shroud (passing through a recess) are permitted if there is a minimum separation of 3 non-cracked vane recesses between 2 cracked recesses.			7500 Flight Hours or 5000 Flight Cycles / 24 calendar months. (whichever comes first)
A sound check (see note below) done on the vanes at, and adjacent to the cracked inner shroud area, must demonstrate no difference in tonality.			This extension may be used again indefinitely in intervals of 3000 hours as long as there is no further deterioration of these conditions. NOTE: Sound tonality check recommendation. A sound tonality check must be done to detect if the abradable material inside the inner shroud is still in contact with the root of the vane. Use a smooth-ended cylindrical tool made of steel with diameter of approximately 0.5 in. (12.70 mm) (for example, a ratchet wrench extension bar). Tools made of aluminum, plastic or wood do not permit the detection of significant variation in the sound tone from one vane to the next. Removal of 2 or 3 fan blades gives a better accessibility to do the check. Be careful to not use a tool or excessive force during the check. This would damage the vanes. Do the check on an area including 3 or 4 vanes on each side of the vane where the cracked inner shroud is located. Place the tool on the LE mid-span of the counterclockwise most vane. Lightly stroke the vane and subsequent vanes in the clockwise direction using a constant speed. Note any variations in the sound tone from one vane to the next. If there is a difference between the vane where the recess is cracked and the other vanes, the stage 1 vane assembly is unserviceable.
(8)Vane LE and TE: Nicks, dents and scratches on LE and TE in areas B and C with a maximum axial length less than 0.117 in. (2.97 mm).			10 cycles or 50 hours (whichever comes first)
Nicks, dents and scratches on LE and TE in area A with a maximum axial length of 0.117 in. (2.97 mm).			2 cycles or 10 hours (whichever comes first)
2.Fan frame
A.Fan frame
(1)Cracks: any number if maximum, length of 0.16 in. (4.06 mm) and minimum separation of 1 in. (25.40 mm).			10 cycles or 25 hours (whichever comes first)
(2)Nicks and dents: any number			10 cycles or 25 hours (whichever comes first)
B.Fan inlet case
(1)Cracks: any number, if maximum length of 0.16 in. (4.06 mm) and minimum separation of 1 in. (25.40 mm).			10 cycles or 25 hours (whichever comes first)
(2)Nicks and scratches: any number			10 cycles or 25 hours (whichever comes first)
(3)Crater in abradable liner (length<5x width) and damage other than crack rub and circumferential defect: if the damage is within the maximum serviceable limit (Ref. AMM TASK 72-23-00-210-003), but the fan case parent metal is exposed and is confirmed via visual inspection to be undamaged.			50 cycles or 125 hours (whichever comes first)
(4)Grooves in abradable liner (oriented within 0 degree to 80 degree from engine axis) and length>5x width: if the damage is within the maximum serviceable limit (Ref. AMM TASK 72-23-00-210-003), but the fan case parent metal is exposed and is confirmed via visual inspection to be undamaged.			50 cycles or 125 hours (whichever comes first)
(5)Circumferential defect in abradable liner (360 degree or oriented within 80 degree to 90 degree from engine axis): for one or a cumulated defect less than 2 in. (50.80 mm) if the fan case parent metal remains not damaged under visual inspection.			50 cycles or 125 hours. (whichever comes first)
C.Outlet Guide Vanes (OGV) for: Inspection/Check of the Fan Outlet Guide Vanes (OGV) ** ON A/C NOT FOR ALL
(1)Broken vane: not serviceable, the broken vane has to be removed prior to next flight.			10-cycle extension if the broken vane is removed. A complete set inspection is required when a new doublet is installed. Replace the vane doublet (Ref. AMM TASK 72-23-00-000-008) and (Ref. AMM TASK 72-23-00-400-008).
(2)Missing vane: one doublet missing			10-cycle extension A complete set inspection is required when a new doublet is installed. Replace the vane doublet (Ref. AMM TASK 72-23-00-000-008) and (Ref. AMM TASK 72-23-00-400-008).
(3)Transversal cracks on inner platform: not more than 30 transversal cracks per platform for the whole set: With not more than 15 transversal cracks included 5 opened transversal cracks maximum in area E. With not more than 15 transversal cracks included 5 opened transversal cracks maximum in area I. And with not more than 15 transversal cracks included 5 opened transversal cracks maximum in area M. Do not change the place of the cracked OGV on the engine for view of transversal cracks and opened transversal cracks. Outlet Guide Vane (OGV) Inner Platform for Cracks ** ON A/C NOT FOR ALL			750-cycle extension, renewable after inspection.
(4)Cracks on outer platform: from or along the airfoil are defined in: Inspection/Check of the Fan Outlet Guide Vanes (OGV) ** ON A/C NOT FOR ALL			50-cycle extension
(5)Metal LE missing: up to 0.78 in. (19.81 mm) in height and 0.39 in. (9.91 mm).			100-cycle extension
(6)Nicks and/or dents, on LE (metallic LE), if damage is between 0.12 in. (3.05 mm) and 0.19 in. (4.83 mm) deep.			A maximum service extension of 100 cycles.
(7)Erosion of composite material, any amount			50 cycles or 125 hours (whichever comes first)
(8)Missing material on only one side of the inner platform for extrados or front edge, see Sheet 1 of: Outlet Guide Vane (OGV) Inner Platform for Missing Material ** ON A/C NOT FOR ALL Less than 0.16 in.2 (103.23 mm2) on two platforms maximum. Do not change the place of an OGV with missing material on the engine. No missing OGV is allowed on the set.			10-cycle extension
(9)Missing material on only one side of the inner platform for intrados or aft edge, see Sheet 1 of: Outlet Guide Vane (OGV) Inner Platform for Missing Material ** ON A/C NOT FOR ALL For 5 platforms maximum and no missing OGV is allowed on the set. Do not change the place of the OGV on the engine.			Outlet Guide Vane (OGV) Inner Platform for Missing Material ** ON A/C NOT FOR ALL
D.OGV inner shroud
(1)Cracks, cut or torn seal at mating with OGV: any amount			25 cycles or 50 hours (whichever comes first)
E.Fan duct panels
(1)One fan duct panel missing is permitted, if you make sure that the Variable Bleed Valve (VBV) area is free of unwanted object before the first aircraft release of the day.			10 cycles
(2)Missing louvers on panel			50 cycles with 3 missing louvers maximum.
F.Splitter fairing
(1)Cracks: any amount			10 cycles or 25 hours (whichever comes first)
G.Mid acoustical panels (1)Disbonded damper more than 20 % of the total surface.			20 cycles
3.Compressor rotor
A.Compressor rotor blades NOTE: The depth of a defect such as a nick is measured along the axis of the damage unless otherwise noted.
(1)Stages 1-4 radial cracks within 0.3 in. (7.62 mm) of the LE and TE more than 0.25 in. (6.35 mm) but less than 0.4 in. (10.16 mm) in length.			10 cycles or 25 hours (whichever comes first)
(2)Stages 1-4 chord-wise cracks more than 0.2 in. (5.08 mm) but less than 0.3 in. (7.62 mm) in length.			10 cycles or 25 hours (whichever comes first)
(3)Stages 1-4 nicks, missing material and erosion on the LE and TE found in Dim. B more than 0.04 in. (1.02 mm) but less than 0.08 in. (2.03 mm) in depth, if the HPC blade is NOT a Tech Insertion stage 4 blade (PN P394XXX).			10 cycles or 25 hours (whichever comes first)
(4)Stages 1-4 nicks, missing material and erosion on the LE and TE found in Dim. B more than 0.03 in. (0.76 mm) but less than 0.08 in. (2.03 mm) in depth, if the HPC blade is a Tech insertion stage 4 blade (PN P394XXX).			10 cycles or 25 hours (whichever comes first)
(5)Stages 1-4 dents on the LE and TE found in Dim. B more than 0.04 in. (1.02 mm) but less than 0.08 in. (2.03 mm) in depth, and less than 0.06 in. (1.52 mm) deflection from the original contour.			10 cycles or 25 hours (whichever comes first)
(6)Stages 1-4 nicks, dents and tears on the LE and TE in Dim. A more than 0.25 in. (6.35 mm) but less than 0.3 in. (7.62 mm) in depth.			10 cycles or 25 hours (whichever comes first)
(7)Stages 1 missing material and erosion at the LE and TE tip corners more than 0.3 in. (7.62 mm) but less than 0.4 in. (10.16 mm) in depth.			10 cycles or 25 hours (whichever comes first)
(8)Stage 2, more than 4 blades missing material and erosion at the LE and TE tip corners more than 0.3 in. (7.62 mm) but less than 0.4 in. (10.16 mm) in depth.			10 cycles or 25 hours (whichever comes first)
(9)Stage 3, more than 5 blades missing material and erosion at the LE and TE tip corners more than 0.3 in. (7.62 mm) but less than 0.4 in. (10.16 mm) in depth.			10 cycles or 25 hours (whichever comes first)
(10)Stage 4, more than 6 blades missing material and erosion at the LE and TE tip corners more than 0.3 in. (7.62 mm) but less than 0.4 in. (10.16 mm) in depth.			10 cycles or 25 hours (whichever comes first)
(11)Stages 1-4 nicks, dents and missing material on the LE and TE of the lower 25% of the airfoil (but not the root radius) more than 0.03 in. (0.76 mm) but less than 0.08 in. (2.03 mm) in depth.			10 cycles or 25 hours (whichever comes first)
(12)Wear and scratches of the TE platform of stage 2 and stage 3 of more than 0.03 in. (0.76 mm) but less than 0.08 in. (2.03 mm) in depth.			10 cycles or 25 hours (whichever comes first)
(13)Stages 2-3 TE root radius nicks, dents and scratches more than 0.03 in. (0.76 mm) but less than 0.08 in. (2.03 mm) in depth.			10 cycles or 25 hours (whichever comes first)
(14)Stages 5-9 radial cracks that are not more than 0.2 in. (5.08 mm) from the LE or TE and more than 0.15 in. (3.81 mm) but less than 0.2 in. (5.08 mm) in length.			10 cycles or 25 hours (whichever comes first)
(15)Stages 5-9 chord-wise cracks that are not more than 0.20 in. (5.1 mm) from the tip and are more than 0.15 in. (3.81 mm) but less than 0.2 in. (5.08 mm) in length.			10 cycles or 25 hours (whichever comes first)
(16)Stages 5-9 nicks, tears, missing material and erosion on the LE and TE found in Dim. B that are more than 0.04 in. (1.02 mm) but less than 0.08 in. (2.03 mm) in depth.			10 cycles or 25 hours (whichever comes first)
(17)Stages 5-9 dents on the LE and TE found in Dim. B that are more than 0.04 in. (1.02 mm) but less than 0.08 in. (2.03 mm) in depth and less than 2 in. (50.80 mm) deflection from the original contour.			10 cycles or 25 hours (whichever comes first)
(18)Stages 5-9 nicks, dents and tears on the LE and TE found in Dim. A that are more than 0.15 in. (3.81 mm) but less 0.2 in. (5.08 mm) in depth.			10 cycles or 25 hours (whichever comes first)
(19)Stages 5-9 missing material and erosion at the LE and TE tip corners if the damage is more than 0.2 in. (5.08 mm) but less than 0.3 in. (7.62 mm) in depth.			10 cycles or 25 hours (whichever comes first)
(20)Stages 5-9 curl on the end of the airfoil when the blade chord is more than 50% but less than 75% of the chord maximum radial length, 0.3 in. (7.62 mm), when it does not engage the stationary parts during operation.			10 cycles or 25 hours (whichever comes first)
(21)Stages 5-9 nicks, dents and missing material edges found in the lower 25% of the airfoil (but not the root radius) more than 0.03 in. (0.76 mm) but less than 0.08 in. (2.03 mm) in depth.			10 cycles or 25 hours (whichever comes first)
(22)Two blade locks in the same stage with any number of cracks if no blade locks are loose on that stage.			10 cycles or 25 hours (whichever comes first)
(23)One loose blade lock in a stage if the other blade lock on the same stage is not loose or cracked.			10 cycles or 25 hours (whichever comes first)
4.Compressor front stator
A.Casing cracks: 0.17 in. (4.32 mm) maximum length in skin			10 cycles or 25 hours (whichever comes first)
B.Casing nicks, pits, scores or scratches, any amount, any depth			10 cycles or 25 hours (whichever comes first)
C.Broken actuation ring connector, one side only, if connector is replaced			5 cycles
D.Vane actuation ring cracks, distortion, bends, twists or distress, provided ring has not separated			5 cycles
E.Loose vane assemblies with metal-to-metal contact on up to 50 % of vanes			10 cycles or 25 hours (whichever comes first)
5.Combustion case
A.Forward and aft flange radial cracks inward from bolt holes			10 cycles
B.Midflange radial cracks			10 cycles
C.Maximum of 10 broken midflange bolts with no more than 4 broken bolts in any group of 20			25 cycles
D.High Pressure Turbine (HPT) shroud cooling and Compressor Discharge Pressure (CDP) pad cracks: more than 0.06 in. (1.52 mm) from bolt holes			10 cycles
6.Combustion chamber
A.Dome assembly
(1)Radial crack in spectacle plate			25 hours
Any number up to 2.5 in. (63.50 mm) in length and not connected to each other.
(2)Circumferential crack in spectacle plate			25 hours
Any number up to 3.6 in. (91.44 mm) in length separated by 4.8 in. (121.92 mm).
(3)Connected cracks in spectacle plate			25 hours
Not more than one (1) radial crack 2.5 in. (63.50 mm) long with one (1) circumferential crack 3.6 in. (91.44 mm) long, separated by 4.8 in. (121.92 mm).
(4)Missing material from spectacle plate			25 hours
The damage is more than the given limits.
(5)Radial crack in deflector or sleeve			25 cycles
Any number up to 0.6 in. (15.24 mm) in length.
(6)Circumferential cracks in deflector or sleeve			25 cycles
Any number up to 0.9 in. (22.86 mm) in length.
(7)Connected cracks in deflector or sleeve			25 cycles
Connection of any radial and circumferential cracks within limits of (5) and (6) above. Limit is exceeded when third crack connects.
(8)Missing material from extensions on deflector
(a)Up to 25 dome cooling holes total in any deflector are exposed.			Do BSI after each 750 cycles
(b)More than 25 exposed dome cooling holes total in any deflector. Refers to the sheets 2 and 3 of the figure: Cracks and Missing Material in the Dome Area ** ON A/C NOT FOR ALL			25 cycles continue-in-service limit
(9)Missing material from extensions on sleeve			50 cycles
Any amount up to 0.24 in. (6.10 mm) maximum depth.
(10)Burn through holes			25 cycles
3 per dome 1.2 in. (30.4799 mm) x 1.2 in. (30 mm) maximum.
(11)Cracks and missing material from the secondary swirl nozzle venturi
(a)Up to 10 secondary swirl nozzle venturis with total missing material at each venturi more than 0.1 in. (2.54 mm) but not more than 0.3 in. (7.62 mm) in width.			Do BSI after each 750 cycles
(b)Any number of secondary swirl nozzle venturis with total missing material more than 0.3 in. (7.62 mm) in width or more than 10 secondary swirl nozzle venturis with total missing material at each venturi more than 0.1 in. (2.54 mm) in width. Refers to the sheets 2 and 3 of the figure: Cracks and Missing Material in the Dome Area ** ON A/C NOT FOR ALL			25 cycles continue-in-service limit
B.Inner and outer liners
(1)Outer liner axial cracks			100 cycles
Up to 5 cracks across more than one panel, and a crack can go across up to 5 panels in sequence.
(2)Outer liner axial cracks from outer side borescope (for all CFM56-5B engines other than CFM56-5B DAC engines)			25 cycles
Up to 5 cracks across more than one panel, and a crack can go across up to 5 panels. At least one of the cooling ribs (3, 4, 5, or 6) does not have cracks that extend through to the outer side. Rib 1 is not cracked through.
(3)Inner liner axial cracks			100 cycles
Up to 5 cracks across more than one panel, and a crack can go across up to 4 panels in sequence.
(4)Circumferential cracks			25 cycles
Any number up to 3 dilution lands in length separated by 3 non-cracked dilution lands.
(5)Connected cracks (for all CFM56-5B engines other than CFM56-5B DAC engines)			100 cycles
Connection of any axial and circumferential cracks up to maximum limits of paragraphs (1), (2), (3), and (4).
(6)Burn through or missing material (a) For each liner, there are not more than 3 holes in adjacent panels that are axially aligned. (b) The maximum size of any hole is less than 6 times the area of a dilution hole. (c) The total area of burn through is less than 24 times the area of a dilution hole.			Repeat BSI every 250 cycles.
(7)Burn through or missing material (a) For each liner, there are more than 3 holes in adjacent panels that are axially aligned. (b) The maximum size of any hole is less than 6 times the area of a dilution hole. (c) The total area of burn through exceeds 24 times the area of a dilution hole.			100 cycles
(8)Missing overhangs			25 cycles
Per liner: 17 areas each twice the size of a dilution hole, providing maximum axial alignment of distress is 3 adjacent panels.
(9)Distortion			25 cycles
Any amount within 0.7 in. (17.78 mm) of original contour.
C.Combustor inner cowl bolts
(1)Missing bolt: maximum of 3 bolts are missing with 4 bolts intact between 2 missing bolts. All other bolts are tight with tack welds intact.			50 cycles for next check, then repeat BSI every 400 cycles.
(2)Bolt tack weld cracked but bolt is not loose: if a maximum of 5 tack welds are cracked, no more than two consecutive, with 4 tack welds intact between two cracked tack welds.			25 cycles for first check, 50 cycles for second check, repeat BSI check 100 cycles.
(3)Bolt tack weld is cracked and bolt is loose: if one or more bolts are loose.			5 cycles
7.HPT nozzle
A.For 5B/P, 5B/3 and 5B/3 PIP: LE missing material, from cracks that interconnect nose holes: (a) The cracks are not longer than 0.3 in. (7.62 mm). (b) The total area of missing material is not more than 0.25 in.2 (161.29 mm2) per vane. Maximum of 4 vanes per 90 degree arc. (c) Missing material does not extend aft of cooling hole rows 3 or 9.			Repeat BSI every 800 cycles.
(1)For 5B/P, 5B/3 and 5B/3 PIP: LE missing material, from cracks that interconnect nose holes, up to 0.3 in.2 (193.55 mm2) per vane. maximum of 4 vanes per 90 degree arc.			25 cycles
B.For 5B/P, 5B/3 and 5B/3 PIP: LE missing material, from other cracks: (a) The cracks are not longer than 0.5 in. (12.70 mm) . (b) The total area of missing material is not more than 0.250 in.2 (161.29 mm2) per vane. Maximum of 4 vanes per 90 degree arc. (c) Missing material does not extend aft of cooling hole rows 3 or 9.			Repeat BSI every 800 cycles.
(1) For 5B/P, 5B/3 and 5B/3 PIP: LE missing material, from other cracks, up to 0.3 in.2 (193.55 mm2) per vane. maximum of 4 vanes per 90 degree arc.			25 cycles
C.For 5B/P, 5B/3 and 5B/3 PIP: LE missing material, from burns or spalling: (a) The total area of missing material is not more than 0.25 in.2 (161.29 mm2) per vane. maximum of 4 vanes per 90 degree arc. (b) Missing material does not extend aft of cooling hole rows 3 or 9.			Repeat BSI every 800 cycles.
(1)For 5B/P, 5B/3 and 5B/3 PIP: LE missing material, from burns or spalling, up to 0.3 in.2 (193.55 mm2) per vane. maximum of 4 vanes per 90 degree arc.			25 cycles
D.Baffle missing material, any amount			10 cycles
E.Concave surfaces of airfoil missing material, from cracking or burn-through, up to 0.45 in.2 (290.32 mm2) per vane			25 cycles
F.For 5B/P, 5B/3 and 5B/3 PIP: convex surfaces of airfoil missing material, from cracking or burn through: NOTE: An open area of the cavity caused by bulging is to be interpreted as missing material where the limits that follow apply. (a) The total area of missing material is not more than 0.05 in.2 (32.26 mm2) per vane. maximum of 4 vanes per 90 degree arc. (b) Cracking or bulging does not occur aft of cooling hole row 16.			Repeat BSI every 800 cycles.
(1)Convex surfaces of airfoil missing material, from cracking or burn through, up to 0.20 in.2 (129.03 mm2) for each vane.			200 cycles
(2)Convex surfaces of airfoil missing material, from cracking or burn through, up to 0.45 in.2 (290.32 mm2) per vane.			25 cycles
G.Inner and outer platforms missing material, from cracking or burn-through, up to 0.5 in. (12.7000 mm) diameter per segment			25 cycles
H.TE missing material up to 0.75 in. (19.05 mm) in axial direction			25 cycles if HPT blades are within limits.
8.HPT rotor blade HPT Blade Inspection (Only Applicable to /P Engines) ** ON A/C NOT FOR ALL
A.TE cracks in area A less than 0.25 in. (6.35 mm) long			10 cycles
B.Convex airfoil cracks within 0.5 in. (12.70 mm) of TE (10 blades maximum) in area B, less than 0.3 in. (7.62 mm) long			25 cycles
C.TE cracks in areas B and C, less than 0.3 in. (7.62 mm) long			40 cycles
D.TE nicks and dents in areas B and C, less than 0.3 in. (7.62 mm) long			40 cycles
E.Radial tip cracks on the convex side not within 0.5 in. (12.70 mm) of the TE, less than 0.35 in. (8.89 mm) long			50 cycles
F.Radial tip cracks on the concave side not within 0.5 in. (12.70 mm) of the TE, less than 1 in. (25.40 mm) long			50 cycles
G.LE cracks in area A, less than 0.1 in. (2.54 mm) long			10 cycles
H.Axial nose or concave gill hole (row 6) cracks in areas B and C, less than 0.05 in. (1.27 mm) in length			10 cycles
J.Axial convex gill hole (row 1) cracks in areas B and C, less than 0.1 in. (2.54 mm) in length			25 cycles
K.Radial nose or gill hole cracks in area B, less than 0.06 in. (1.52 mm) long			10 cycles
L.Radial nose or gill hole cracks in area C, less than 0.03 in. (0.76 mm) long			10 cycles
M.Missing material at TE tip and area A, up to 0.5 in. (12.70 mm) axially x 0.75 in. (19.05 mm) radially			50 cycles
N.Through wall hole in area A and area B (1)Any number of blades if cavity 2 is not exposed on any of the blades.			25 cycles
P.Through wall hole in area C, less than 0.3 in. (7.62 mm) in diameter or 0.071 in.2 (45.81 mm2) equivalent area			50 cycles
Q.Airfoil tip bent, curled, or missing material if the missing material below the tip shelf is less than 0.05 in. (1.27 mm) in diameter			10 cycles
R.Airfoil convex and concave surface nicks or dents in areas A, B and C if no cracks or missing material			25 cycles
S.Axial and radial cracks in areas B and C, including root radius, that do not intersect nose or gill holes less than 0.1 in. (2.54 mm) in length			10 cycles
9.HPT shroud and stage 1 Low Pressure Turbine (LPT) nozzle
A.HPT shrouds
(1)Circumferential cracks that are not connected and are more than 1 in. (25.40 mm) long.			25 cycles
(2)Circumferential cracks more than 0.25 in. (6.35 mm) long or closer than 0.25 in. (6.35 mm) from the shroud edge that connect to axial cracks, unless the connected cracks are within the limit for missing material, then missing material limit can be used.			25 cycles
(3)Burn-through of shroud rub land on all HPT shrouds in or less than 0.001 in.2 (0.645 mm2) < Area < 0.005 in.2 (3.226 mm2) is permitted if the shroud does not drop into the flowpath. NOTE: This C-I-S limit is for a reduced interval, repeat inspection.			75 cycles
(4)Burn-through of shroud rub land on all HPT shrouds in or less than 0.005 in.2 (3.226 mm2) < Area < 0.015 in.2 (9.677 mm2) is permitted if the shroud does not drop into the flowpath. NOTE: This C-I-S limit is for a reduced interval, repeat inspection.			25 cycles
(5)Burn-through of shroud rub land on all HPT shrouds when Area > 0.015 in.2 (9.677 mm2) is permitted if the shroud does not drop into the flowpath.			25 cycles
(6)Material loss on split-line forward corners more than 0.250 in. (6.35 mm) in axial direction and 0.080 in. (2.03 mm) in circumferential direction is permitted, if there is no other burn-through on the shroud. NOTE: This C-I-S limit is for a reduced interval, repeat inspection.			400 cycles
(7)Material loss on split-line on areas different than forward and aft corners is permitted if area (A) is above 0.013 in.2 (8.387 mm2) OR distance from original contour in circumferential direction (d) is above 0.080 in. (2.03 mm), if there is no other burn-through on the shroud. NOTE: This C-I-S limit is for a reduced interval, repeat inspection.			400 cycles
(8)Material loss on split-line on areas different than forward and aft corners is permitted if area (A) is above 0.013 in.2 (8.387 mm2) AND distance from original contour in circumferential direction (d) is above 0.080 in. (2.03 mm), if no other burn-through on the shroud. NOTE: This C-I-S limit is for a reduced interval, repeat inspection.			200 cycles
(9)Material loss on split-line on areas different than forward and aft corners is permitted if area (A) is above 0.013 in.2 (8.387 mm2) AND distance from original contour in circumferential direction (d) is above 0.080 in. (2.03 mm) AND when other burn-through with the area over 0.001 in.2 (0.645 mm2) is on the shroud.			25 cycles
B.Stage 1 LPT nozzle Example of Axial Cracks, Radial Cracks and Holes on Stage 1 LPT Nozzle Segment ** ON A/C NOT FOR ALL NOTE: An axial crack is considered as full axial crack if it runs from LE to TE on the two concave and convex sides.
(1)Axial crack in LE and TE (a) Rigid borescope inspection: One crack on each airfoil if crack length is between 1/2 of the chord width 1 in. (25.40 mm) and 2/3 of the chord width 1.2 in. (30.48 mm) and no missing material.			100 cycles
(b) Flexible borescope inspection: Missing material and full axial crack from LE to TE. 1. Each individual hole must not exceed 0.039 in.2 (25.16 mm2). 2. There are maximum 2 holes per segment and maximum 1 hole per airfoil. 3. A maximum of 2 full cracks (LE to TE) per LPT nozzle segment are accepted. 4. A maximum of 1 full crack (LE to TE) per airfoil added to any amount of non-full cracks is accepted. 5. The axial cracks radial distance is more than 0.472 in. (11.99 mm).			Airfoil with Missing Material or Full Axial Crack from LE to TE ** ON A/C NOT FOR ALL
(c) Flexible borescope inspection: Missing material and full axial crack from LE to TE. 1. Each individual hole must not exceed 0.039 in.2 (25.16 mm2). 2. There are maximum 2 holes per segment and maximum 1 hole per airfoil. 3. A maximum of 2 full cracks (LE and TE) per LPT nozzle segment are accepted. 4. A maximum of 1 full crack (LE to TE) per airfoil added to any amount of non-full cracks is accepted. 5. The axial cracks radial distance is less than 0.472 in. (11.99 mm). 6. The axial cracks remain parallel.			Airfoil with Missing Material or Full Axial Crack from LE to TE ** ON A/C NOT FOR ALL
(d) Flexible borescope inspection: Missing material and full axial crack from LE to TE. 1. Each individual hole must not exceed 0.039 in.2 (25.16 mm2). 2. There are maximum 2 holes per segment and maximum 1 hole per airfoil. 3. A maximum of 2 full cracks (LE and TE) per LPT nozzle segment are accepted. 4. A maixmum of 1 full crack (LE to TE) per airfoil added to any amount of non-full cracks is accepted. 5. The axial cracks radial distance is less than 0.472 in. (11.99 mm) and there is one crack curved.			Airfoil with Missing Material or Full Axial Crack from LE to TE ** ON A/C NOT FOR ALL
(e) Flexible borescope inspection: Missing material and full axial crack from LE to TE. 1. Each individual hole must not exceed 0.039 in.2 (25.16 mm2). 2. There are maximum 2 holes per segment and maximum 1 hole per airfoil. 3. A maximum of 2 full cracks (LE to TE) per LPT nozzle segment are accepted. 4. A maximum of 1 full crack (LE to TE) per airfoil added to any amount of non-full cracks is accepted. 5. The cracks are intersected.			Airfoil with Missing Material or Full Axial Crack from LE to TE ** ON A/C NOT FOR ALL
(2)Radial crack: (a) Each airfoil can only have one crack that is less than 1/2 of the chord width in length 1 in. (25.40 mm). Flexible borescope inspection: 1. Each individual hole must not exceed 0.039 in.2 (25.16 mm2). 2. There are maximum 2 holes per segment and maximum 1 hole per airfoil. 3. A maximum of 2 full cracks (LE to TE) per LPT nozzle segment are accepted. 4. A maximumof 1 full crack (LE to TE) per airfoil added to any amount of non-full cracks is accepted.			Airfoil with Missing Material or Full Axial Crack from LE to TE ** ON A/C NOT FOR ALL
(3)Burns, erosion, corrosion: Melted or missing material more than 0.102 in.2 (65.81 mm2) for each engine set of nozzle.			25 cycles
(4)Crack in outer and inner platforms up to 1 in. (25.40 mm).			100 cycles
10.LPT Rotor
A.LPT blades (all stages)
(1)Blade pretwist
Total gap, for stage 1, up to 0.1 in. (2.54 mm).			5 cycles
Stage 2-4 gaps such that adjacent interlocks do not contact each other.			5 cycles
(2)0.08 in. (2.03 mm) maximum deflection over a length 10 times longer maximum, only for stage 1 LPT blades distorted LEs, due to overtemperature.			15 cycles
(3)Stage 1, 2, 3 blades
Area E: Any amount of impact damage/rubbing provided there is no missing material or cracks.			5 cycles or 10 hours (whichever comes first)
Other areas: Any amount of impact damage such as bending, nicks and/or dents is allowed provided there is no missing material or cracks exceeding 50 % of chord width.			5 cycles or 10 hours (whichever comes first)
(4)Stage 4 blades
Any amount of tip shroud interlock wear allowed.			25 cycles or 50 hours (whichever comes first)
Blade tip shroud protrusion not to exceed 0.04 in. (1.02 mm).			10 cycles or 25 hours (whichever comes first)
Area E:
Any amount of impact damage such as nicks and/or dents is allowed provided there is no missing material or cracks.			5 cycles or 10 hours (whichever comes first)
Other areas:
Any amount of impact damage. One complete airfoil and any number of tip shrouds with associated airfoil tips may be missing provided engine vibration is not excessive.			5 cycles or 10 hours (whichever comes first)
Blade tip shrouds shingled or unlatched provided rotor turns freely and engine vibration is not excessive.			5 cycles or 10 hours in shingled condition. (whichever comes first)
(5)Stage 2 Blades (for CFM56-5B DAC engines)
Blades tip shroud mismatch:
1 to 15 blades concerned, any amount of tip shroud mismatch.			Repeat BSI 4000 cycles.
More than 15 blades concerned, any amount of tip shroud mismatch.			Repeat BSI 2000 cycles.
Blades tip shroud notch wear:
1 to 7 blades of the set with irregular shape wear on notch.			Repeat BSI 1000 cycles.
More than 7 blades of the set with irregular shape wear on notch.			Remove within 500 cycles.
B.Nozzle segments 2 to 4
(1)Three cracks maximum for each nozzle segment if cracks are more than 0.5 in. (12.70 mm) (1/3 of the chord width) and less than 1 in. (25.40 mm) (2/3 of the chord width) if the adjacent nozzle segments have no more than two cracks more than 0.5 in. (12.70 mm) (1/3 of the chord width) and less than 1 in. (25.40 mm) (2/3 of the chord width).			200 cycles
(2)One crack maximum for each nozzle segment that is more than 1 in. (25.40 mm) (2/3 of the chord width) including open airfoil.			200 cycles
(3)One full chord crack on two airfoils for each segment if the adjacent nozzle segments have no more than one airfoil with a full chord crack.			25 cycles
(4)Nicks, dents, tears, missing pieces up to 2 in.2 (1290.32 mm2) on nonadjacent vanes provided there are no cracks extending from distressed areas.			10 cycles
(5)Burned areas with missing material or melted.			25 cycles
C.Stage 4 shroud abradable material
(1)Worn, jagged or crushed sealing surface exceeding 50 % of the honeycomb height provided sectors of the shroud abradable material are not missing.			10 cycles
11.LPT Casing
A.Forward and aft flanges
(1)One crack connecting 2 bolt holes without penetrating pressure vessel outer skin.			10 cycles
(2)One crack into skin, 0.4 in. (10.16 mm) long maximum			10 cycles
B.External surface of the casing
(1)One crack, 0.4 in. (10.16 mm) long maximum			10 cycles
C.Cooling air tube and manifold assemblies			10 cycles
(1)One separated circumferential tube
(2)3 in. (76.20 mm) cumulative cooling air manifold crack
(3)One separated cooling air tube support
D.Thread ports and bosses
(1)One crack, 0.5 in. (12.70 mm) maximum providing there is no leakage			10 cycles
12.Turbine frame
A.Forward and aft flanges			10 cycles
(1)One circumferential crack connecting two bolt holes
(2)One crack into skin, 0.5 in. (12.70 mm) maximum
B.Engine mounting lug areas airframe attach points only			10 cycles
(1)One crack out of one mount lug bolt hole, 0.25 in. (6.35 mm) maximum
(2)Skin crack, 0.25 in. (6.35 mm) maximum
C.Threaded parts and bosses			10 cycles
(1)One crack, 0.5 in. (12.70 mm) long providing there is no fluid or air leakage
D.Stud on the aft face of the inner hub
(1)Missing/broken/loose stud(s):
One (1) or two (2) studs			500 cycles or 500 hours (whichever comes first)
Three (3) studs:
*If not adjacent to each other			500 cycles or 500 hours (whichever comes first)
*If two (2) non-serviceable studs are adjacent, but the third one is separated from them by two (2) serviceable studs			500 cycles or 500 hours (whichever comes first)
*If not			Replace studs.
Four (4) studs or more			Replace studs.
E.Thermal insulation blankets			100 cycles
(1)Missing or protruding blankets
F.Other areas			10 cycles
(1)One crack, 0.25 in. (6.35 mm) maximum
13.Accessory gearbox
A.Two opposite keylock studs missing, provided there is no leakage at flange.			3 cycles or 30 hours (whichever comes first)
B.Oil leakage from AGB/Starter carbon seal (Ref. AMM TASK 79-00-00-210-003).			10 cycles provided seal drain line is disconnected and drain cavity is capped.

[Rev.10 from 2021] 2026.04.01 02:40:47 UTC