W DOC AIRBUS | AMM A320F

Visual Inspection of the Fan Blade [CFML]

TASK 72-21-20-210-802-A
Visual Inspection of the Fan Blade

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: 210
ZONE: 400
1. Reason for the Job
This procedure gives the criteria for the fan blades.
NOTE: The inspection criteria below are applicable after the removal of the high metal and high composite.
NOTE: You can use equivalent alternatives for standard tools, equipment and consumable materials.
2. Job Set-up Information
 A. Fixtures, Tools, Test and Support Equipment
REFERENCE
QTY
DESIGNATION
No specific
AR
MAT - PROTECTIVE
No specific
1
PENCIL
No specific
AR
WARNING NOTICE(S)
 B. Work Zones and Access Panels
ZONE/ACCESS
ZONE DESCRIPTION
210
CKPT,FWD COMPT BHD TO FLT COMPT BULKHEAD
400
POWER PLANT, NACELLES AND PYLONS
 C. Referenced Information
REFERENCE
DESIGNATION
TASK 72-21-20-300-801-A
Replacement of Fan Blade Coating (Local Repair of the Platform Wear-Strips with Polyurethane Paste)
TASK 72-21-20-320-801-A
Blending of the Metal Leading Edge Fan Blades
TASK 72-21-20-370-801-A
Local Repair of the Anti-Erosion Paint Fan Blades
TASK 72-21-20-960-802-A
Fan Blades - Bonding of Labels (Full Repair of the Identification and MOMENTS WEIGHT Labels and Bonding of Cotton Labels)
SPM 701021
F Metallic Leading Edge Sidewall
F Metallic Leading Edge Nose and Sidewall
F Trailing Edge
F Bottom Root Radius
F Leading and Trailing Edge Pressure Face Radius
F Fan Blade Dovetail
F Example of Visual Indications
F Blade Coatings and Wear Strips
F Metallic Leading Edge Close to Tip at Concave Side
F Fan-Blade Identification Label
3. Job Set-up
Subtask 72-21-20-941-060-A
A. Safety Precautions
   (1) On the center pedestal, on ENG panel 115VU:
     (a) Make sure that the ENG/MODE selector switch is in the NORM position.
     (b) Make sure that the ENG/MASTER 1(2) control switch was in the OFF position not less than five minutes before you do this procedure.
     (c) Make sure that WARNING NOTICE(S) are in position to tell persons not to operate:
  • The ENG/MODE selector switch
  • The ENG/MASTER 1(2) control switch.
   (2) On the ENG section of maintenance panel 50VU:
     (a) Make sure that the ON legend of the FADEC GND PWR/1(2) pushbutton switch is off.
     (b) Make sure that WARNING NOTICE(S) is in position to tell persons not to energize FADEC 1(2).
   (3) Install the MAT - PROTECTIVE in the lower half of the inlet cowl.
4. Procedure
Subtask 72-21-20-210-051-A
A. Visual Inspection of the Fan Blade
NOTE: An area of the metallic Leading Edge (LE) is painted. On this area, use the paint criteria first, then the metallic LE criteria, if you can see the metal.
INSPECT/CHECK
MAXIMUM SERVICEABLE LIMITS
REMARKS
1.Visual examination of the metallic LE sidewall in Area A.


A.Disbonding at the concave (pressure) side.
One disbonded area of 0.2 in.2 (129.03 mm2) is permitted.
If the disbonding detected, perform the tap test to determine the disbonded surface. Refer to Para. 4.B.
B.Disbonding at the convex (suction) side.
One disbonded area of 0.2 in.2 (129.03 mm2) is permitted.
If the disbonding detected, perform the tap test to determine the disbonded surface. Refer to Para. 4.B.
C.Nicks, dents, scratches.
Any number up to 0.0019 in. (0.05 mm) in depth.
See repair (Ref. AMM TASK 72-21-20-320-801).
D.Wear, erosion.
Not serviceable.

E.Crease.
Not serviceable.

F.Cracks, tears.
Any amount.

2.Visual examination of the metallic LE nose in Area B1.


A.Nicks, dents, scratches.
Any number up to 0.007 in. (0.18 mm) in depth.
See repair (Ref. AMM TASK 72-21-20-320-801).
B.Cracks, tears.
Not serviceable.
3.Visual examination of the metallic LE sidewall in Area B2.


A.Disbonding at the concave (pressure) side.
One disbonded area of 0.2 in.2 (129.03 mm2) is permitted.
If disbonding detected, perform the tap test to determine the disbonded surface. Refer to Para. 4.B.
B.Disbonding at the convex (suction) side.
One disbonded area of 0.2 in.2 (129.03 mm2) is permitted.
If the disbonding detected, perform the tap test to determine the disbonded surface. Refer to Para. 4.B.
C.Nicks, dents, scratches.
Any number up to 0.0019 in. (0.05 mm) in depth.

D.Wear, erosion.
Not serviceable.

E.Crease.
Not serviceable.

F.Cracks, tears.
Not serviceable.

4.Visual examination of the metallic LE nose in Area C1.


A.Nicks, dents, scratches.
Any number up to 0.007 in. (0.18 mm) in depth.
See repair (Ref. AMM TASK 72-21-20-320-801).
B.Cracks, tears.
Not serviceable.

5.Visual examination of the metallic LE sidewall in Area C2.


A.Disbonding at the concave (pressure) side.
One disbonded area of 0.2 in.2 (129.03 mm2) is permitted.
If disbonding detected, perform the tap test to determine the disbonded surface. Refer to Para. 4.B.
B.Disbonding at the convex (suction) side.
One disbonded area of 0.2 in.2 (129.03 mm2) is permitted.
If the disbonding detected, perform the tap test to determine the disbonded surface. Refer to Para. 4.B.
C.Nicks, dents, scratches.
Any number up to 0.0059 in. (0.15 mm) in depth.

D.Wear, erosion.
Not serviceable.

E.Crease.
Not serviceable.

F.Cracks, tears.
Not serviceable.

6.Visual examination of the metallic LE nose in Area D1.


A.Nicks, dents, scratches.
Any number up to 0.011 in. (0.28 mm) in depth.
The continue-in-service limit of 50 cycles is permitted with the criteria: Any number up to 0.0141 in. (0.36 mm) in depth. See repair (Ref. AMM TASK 72-21-20-320-801).
B.Cracks, tears.
Not serviceable.

7.Visual examination of the metallic LE sidewall in Area D2.


A.Disbonding at the concave (pressure) side.
One disbonded area of 0.2 in.2 (129.03 mm2) permitted.
If the disbonding detected, perform the tap test to determine the disbonded surface. Refer to Para. 4.B.
B.Disbonding at the convex (suction) side.
One disbonded area of 0.2 in.2 (129.03 mm2) permitted.
If the disbonding detected, perform the tap test to determine the disbonded surface. Refer to Para. 4.B.
C.Nicks, dents, scratches.
Any number up to 0.0059 in. (0.15 mm) in depth.

D.Wear, erosion.
Not serviceable.

E.Crease.
Not serviceable.

F.Cracks, tears.
Not serviceable.

8.Visual examination of the metallic LE nose in Area E1.


A.Nicks, dents, scratches.
Any number up to 0.031 in. (0.8 mm) in depth.
The continue-in-service limit of 50 cycles is permitted with the criteria: Any number up to 0.0492 in. (1.25 mm) in depth. See repair (Ref. AMM TASK 72-21-20-320-801).
B.Cracks, tears.
Not serviceable.

9.Visual examination of the metallic LE sidewall in Area E2.


A.Nicks, dents, scratches.
Any number up to 0.0059 in. (0.15 mm) in depth.

B.Wear, erosion.
Not serviceable.

C.Cracks, tears.
Not serviceable.

D.Crease.
Not serviceable.

10.Visual examination of the metallic LE nose in Area F1.


A.Nicks, dents, scratches.
Any number up to 0.039 in. (1.0 mm) in depth.
The continue-in-service limit of 50 cycles is permitted with the criteria: Any number up to 0.078 in. (2.0 mm) in depth. See repair (Ref. AMM TASK 72-21-20-320-801).
B.Cracks, tears.
Not serviceable.

C.Coloration up to 0.197 in. (5.0 mm) from tip at the concave side.
Any amount.

11.Visual examination of the metallic LE sidewall in Area F2.


A.Nicks, dents, scratches.
Any number up to 0.0059 in. (0.15 mm) in depth.

B.Wear, erosion.
Not serviceable.

C.Cracks, tears.
Not serviceable.

D.Crease.
Not serviceable.

E.Coloration up to 0.197 in. (5.0 mm) from tip at the concave side.
Any amount.

12.Visual examination of the metallic LE sidewall in Areas E1, E2, F1 and F2 including X2, Y2.


A.Disbonding at the concave (pressure) side other than Area X2.
Not serviceable.

B.Disbonding at the concave (pressure) side in Area X2.
Any amount permitted.
If disbonding detected:
  • Perform the tap test to determine the disbonded surface on the Areas X2, Y2, F2, E2, D2, C2. Refer to Para. 4.B.
  • Visually check the convex (suction) side for disbonding on the Areas C2, D2, E2, F2 per corresponding paragraphs of this task.
C.Disbonding at the concave (pressure) side Y2.
Not serviceable.
If disbonding detected:
  • Perform the tap test to determine the disbonded surface on the Areas X2, Y2, F2, E2, D2, C2. Refer to Para. 4.B.
  • Visually check the convex (suction) side for the disbonding on the Areas C2, D2, E2, F2 per corresponding paragraphs of this task.
The continue-in-service limit of 100 cycles is permitted for one of the two engines and for the six fan blades, with the criteria: Any amount permitted.
D.Disbonding at the convex (suction) side.
Up to 0.47 in. (11.94 mm) in width and 3.93 in. (99.82 mm) in cumulative length.
If disbonding detected:
  • Perform the tap test to determine the disbonded surface on the Areas F2, E2, C2, D2. Refer to Para. 4.B.
  • Visually check the concave (pressure) side for disbonding on the Areas C2, D2, E2, F2, X2, Y2 per corresponding paragraphs of this task.
The continue-in-service limit of 100 cycles is permitted for one of the two engines with the criteria: Up to 0.70 in. (17.78 mm) in width and 3.93 in. (99.82 mm) in cumulative length.
13.Visual examination of the blade tip in Area G1.
NOTE: Only one engine is authorized to have the fan blades (1) over the serviceable limits.


A.Tip contact, tip rub: melt resin, frayed carbon fiber.
Any amount.

B.Material deposit on the surface.
Any amount.

C.Surface decohesion (coating relief) on the convex side.
Any amount (within Area G1).
If any indications detected, perform visual inspection of the metallic LE Areas C2, D2, E2, F2, X2, Y2 on the concave (pressure) and the convex (suction) sides per corresponding paragraphs of this task. The continue-in-service limit of 100 cycles is permitted for one of the two engines and for six fan blades (1) with the criteria: Up to 3.93 in. (99.82 mm) in length in radial direction and 0.047 in. (1.19 mm) in the thickness over profile.
D.Tears, cracks, fiber breakage on the convex side (open crack with white primer visible).
One permitted, 1.18 in. (30 mm) in length in radial direction (Ld) and 0.047 in. (1.2 mm) of the thickness over profile (p).
The continue-in-service limit of 100 cycles is permitted for one of the two engines and for six fan blades (1): One permitted, 1.57 in. (40 mm) in long in radial direction (Ld) and 0.047 in. (1.2 mm) of thickness over profile (p). If any indications detected, perform visual inspection of the metallic LE Areas C2, D2, E2, F2, X2, Y2 on the concave (pressure) and the convex (suction) sides per corresponding paragraphs of this task. If any indications detected, check for surface decohesions on Area M.
E.Surface decohesion (coating relief) on the concave side.
Any amount (within Area G1), 0.019 in. (0.5 mm) of thickness over profile (p).
If any indications detected, perform visual inspection of the metallic LE Areas C2, D2, E2, F2, X2, Y2 on the concave (pressure) and the convex (suction) sides per corresponding paragraphs of this task.
F.Tears, cracks, fiber breakage on concave side.
Not serviceable.
The continue-in-service limit of 100 cycles is permitted for one of the two engines and for six fan blades (1): One permitted, 0.39 in. (10 mm) in length in radial direction (Ld) and 0.047 in. (1.2 mm) of thickness over profile (p). If any indications detected, perform visual inspection of the metallic LE Areas C2, D2, E2, F2, X2, Y2 on the concave (pressure) and the convex (suction) sides per corresponding paragraphs of this task. If any indications detected, check for surface decohesions on Area M.
G.White line on the black paint alongside the LE sidewalls on the concave and the convex sides.
Any amount, if disbonded surfaces of the LE sidewalls are within criterias (paragraph for visual examination of the metallic LE sidewall).
If any indications detected, perform visual inspection of the metallic LE Areas C2, D2, E2, F2, X2, Y2 on the concave (pressure) and the convex (suction) sides per corresponding paragraphs of this task. If any indications detected, check for surface decohesions on Area M.
14.Visual examination of the blade tip in Area G2.


A.Tip contact, tip rub: melt resin, frayed carbon fiber.
Any amount.

B.Material deposit on the surface.
Any amount.

C.Decohesions, tears, cracks, fiber breakage.
Any number up to 0.11 in. (2.79 mm) in length in tangential direction.

15.Visual examination of the blade tip in Area H.


A.Tip contact, tip rub: melt resin, frayed carbon fiber.
Any amount.

B.Material deposit on the surface.
Any amount.

C.Decohesions, tears, cracks, fiber breakage for distance 0 in. (0.00 mm) to 0.19 in. (4.83 mm) from tip.
Any number up to 0.11 in. (2.79 mm) in length in tangential direction.

D.Decohesions lines if not starting from Trailing Edge (TE) for distance more than 0.19 in. (4.83 mm) to 5.51 in. (139.95 mm) from tip.
Any number.
If any indications detected, perform visual inspection of the metallic LE Areas C2, D2, E2, F2, X2, Y2 on the concave (pressure) and the convex (suction) sides per corresponding paragraphs of this task.
16.Visual examination of the blade in Area J.

A.Decohesions line if not starting from TE.
Any number.
If any indications detected, perform visual inspection of the metallic LE Areas C2, D2, E2, F2, X2, Y2 on the concave (pressure) and the convex (suction) sides per corresponding paragraphs of this task.
17.Visual examination of the TE in Areas H, J, K and L.


A.Decohesions, tears, cracks, fiber breakage 0.19 in. (4.83 mm) from TE.
Any number.

B.Decohesions, tears, cracks, fiber breakage more than 0.19 in. (4.83 mm) to 1.18 in. (29.97 mm) from TE for Areas J, K and L and more than 0.19 in. (4.83 mm) to 1.37 in. (34.80 mm) from TE for Area H.
Two indications permitted in Area L and five cumulated indications permitted over Areas H, J, K and L and up to 5.11 in. (129.79 mm) in cumulated axial length from TE.
If any indications detected, perform visual inspection of the metallic LE Areas C2, D2, E2, F2, X2, Y2 on the concave (pressure) and the convex (suction) sides per corresponding paragraphs of this task.
C.Decohesions, tears, cracks, fiber breakage in TE more than 1.18 in. (29.97 mm) to 1.57 in. (39.88 mm) from TE for Areas J, K and L and more than 1.37 in. (34.80 mm) to 1.77 in. (44.96 mm) from TE for Area H.
Not serviceable.
If any indications detected, perform visual inspection of the metallic LE Areas C2, D2, E2, F2, X2, Y2 on the concave (pressure) and the convex (suction) sides per corresponding paragraphs of this task. The continue-in-service limit of 50 cycles is permitted with the criteria: Two indications permitted in Area L and five cumulated indications permitted over Areas H, J, K and L and up to 7.08 in. (179.83 mm) in cumulated axial length from TE.
D.Steps in TE in Areas H, J and K.
Up to 0.03 in. (0.76 mm) in thickness.
If any indications detected, perform visual inspection of the metallic LE Areas C2, D2, E2, F2, X2, Y2 on the concave (pressure) and the convex (suction) sides per corresponding paragraphs of this task.
E.Steps in LE in Area L.
Not serviceable.

18.Visual examination of the blade airfoil in Area M.


A.Tears, cracks, fiber breakage (open crack with white primer visible)
Not permitted.

B.Surface decohesions (coating relief) forming a line.
Any amount.

C.Surface decohesions (coating relief) forming an area.
Maximum surface: 1 area of 9.3 in.2 (6000 mm2).
D.White line on black paint alongside LE sidewalls on the concave and the convex side.
Any amount if disbonded surfaces of the LE sidewalls are within for visual examination of the metallic LE sidewall.

19.Visual examination of the blade airfoil in Areas G1, G2, H, J, K, L and M.

NOTE: If one or several tears or cracks in Areas G1, H, J, K, L are detected, then check for surface decohesions on Area M.
A.Black paint coat on the concave (pressure) and the convex (suction) side for missing material.
Any amount.
See repair (Ref. AMM TASK 72-21-20-370-801).
B.Black paint coat on the concave (pressure) and convex (suction) side for disbonding, wear, indentations.
Any amount.

C.Black rubber polyurethane coating on the concave (pressure) side for erosion, disbonding.
Any amount if composite fiber is not visible.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
D.Black rubber polyurethane coating on the concave (pressure) side for loose or missing material from 0 in. (0 mm) to 0.39 in. (10 mm) from the tip.
  • Maximum surface: 1.5 in.2 (1000 mm2)
  • Maximum cumulated surface for the 18 blades: 7.7 in.2 (5000 mm2)
  • The loose coating must be cut away.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
E.Black rubber polyurethane coating on the concave (pressure) side for loose or missing material beyond 0.39 in. (10 mm) from tip.
Up to 0.038 in.2 (25 mm2) if the loose coating is cut away.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
F.Primer on the convex (suction) side for missing material.
Up to 0.03 in.2 (19.35 mm2) in surface if the loose coating is cut away.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
G.Primer on the concave (pressure) side for erosion, loose or missing material.
Any amount.
See repair (Ref. AMM TASK 72-21-20-370-801).
H.Nicks or dents in composite on the concave (pressure) and the convex (suction) side if up to 0.007 in. (0.18 mm) in depth.
  • Any number
  • Any amount.
NOTE: If nicks or dents measurement is performed from the coating it is necessary to add 0.01783 in. (0.453 mm) on the pressure side and 0.00216 in. (0.055 mm) on the suction side to the criteria above. Therefore, nicks and dents limit measured from the concave coating is 0.0188 in. (0.48 mm) + 0.01783 in. (0.453 mm) = 0.03661 in. (0.93 mm) and 0.0188 in. (0.48 mm) + 0.00216 in. (0.055 mm) = 0.02106 in. (0.535 mm) from the convex painted surface.
J.Nicks or dents in composite on the concave (pressure) and the convex (suction) side if depth is more than 0.007 in. (0.18 mm) to 0.019 in. (0.48 mm).
  • Any number
  • Up to 0.0155 in.2 (10 mm2) in surface for each nick or dent
  • Minimum distance of 0.79 in. (20.07 mm) between two indications.
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • Any number
  • Up to 0.02 in.2 (12.90 mm2) in surface for each nick or dent
  • Minimum distance of 0.79 in. (20.07 mm) between two indications.
NOTE: If nicks or dents measurement is performed from the coating it is necessary to add 0.01783 in. (0.453 mm) on the pressure side and 0.00216 in. (0.055 mm) on the suction side to the criteria above. Therefore, nicks and dents limit measured from the concave coating is 0.0188 in. (0.48 mm) + 0.01783 in. (0.453 mm) = 0.03661 in. (0.93 mm) and 0.0188 in. (0.48 mm) + 0.00216 in. (0.055 mm) = 0.02106 in. (0.535 mm) from the convex painted surface.
K.Nicks or dents in composite on the concave (pressure) and the convex (suction) side if depth is more than 0.019 in. (0.48 mm) to 0.039 in. (0.99 mm).
Not serviceable.
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • Any number
  • Up to 0.02 in.2 (12.90 mm2) in surface for each nick or dent
  • Minimum distance of 0.79 in. (20.07 mm) between two indications.
L.Scratches in composite on the concave (pressure) and the convex (suction) side if up to 0.007 in. (0.18 mm) in depth.
  • Any number
  • Any amount.
M.Scratches in composite on the concave (pressure) and the convex (suction) side if depth is more than 0.007 in. (0.18 mm) to 0.019 in. (0.48 mm).
Not serviceable.
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • Any number
  • Any amount.
N.Indentation line of the paint at the end of the metallic LE side wall on the convex (suction) and the concave (pressure) side.
Any amount.
20.Visual examination of the fan blade (1) dovetail and shank (if the fan blade (1) is removed from the fan disk) in Area N.


A.Cracks, tears, fiber breakage.
Not serviceable.
B.Nicks, dents on the concave (pressure) surface.
  • Up to 0.008 in. (0.2 mm) in depth
  • Up to 0.08 in. (2 mm) in width
  • Up to 1.97 in. (50 mm) in cumulated length.
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • Up to 0.04 in. (1 mm) in depth
  • Up to 0.2 in. (5 mm) in width
  • Up to 1.97 in. (50 mm) in cumulated length.
C.Nicks, dents on the convex (suction) surface.
  • Up to 0.008 in. (0.2 mm) in depth
  • Up to 0.08 in. (2 mm) in width
  • Up to 1.97 in. (50 mm) in cumulated length.
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • Up to 0.04 in. (1 mm) in depth
  • Up to 0.2 in. (5 mm) in width
  • Up to 1.97 in. (50 mm) in cumulated length.
D.Scratches on the concave (pressure) surface if depth is up to 0.004 in. (0.1 mm).
  • Any number
  • Any length.
E.Scratches on the concave (pressure) surface if depth is more than 0.004 in. (0.1 mm) and up to 0.008 in. (0.2 mm).
  • Any number
  • Up to 1.18 in. (30 mm) in length.
F.Scratches on the concave (pressure) surface if depth is more than 0.008 in. (0.2 mm) and up to 0.04 in. (1.0 mm).
Not permitted.
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • One scratch permitted
  • Up to 3.54 in. (90 mm) in length.
G.Scratches on the convex (suction) surface if depth is up to 0.004 in. (0.1 mm).
  • Any number
  • Any length.
H.Scratches on the convex (suction) surface if depth is more than 0.004 in. (0.1 mm) and up to 0.008 in. (0.2 mm).
  • Any number
  • Up to 1.18 in. (30 mm) in length.
J.Scratches on the convex (suction) surface if depth is more than 0.008 in. (0.2 mm) and up to 0.04 in. (1.0 mm).
Not permitted.
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • One scratch permitted
  • Up to 3.54 in. (90 mm) in length.
K.Disbonding, missing material of the label.
Not serviceable.
The continue-in-service limit of 1000 cycles is permitted with the criteria: missing or disbonded if P/N and S/N of metallic LE is fully legible. See repair (Ref. AMM TASK 72-21-20-960-802).
F Fan-Blade Identification Label
NOTE: This over serviceable limit extension is for a reduced interval. Repeat the inspection for legible metallic LE to allow a new continue-in-service limit of 1000 cycles.
21.Visual examination of the fan blade (1) dovetail and shank (if the fan blade (1) is removed from the fan disk) in Area T.


A.Cracks, tears, fiber breakage.
Not serviceable.

B.Nicks or dents on the concave (pressure) surface.
  • Up to 0.008 in. (0.2 mm) in depth
  • Up to 0.08 in. (2 mm) in width
  • Up to 0.39 in. (10 mm) in cumulated length.
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • Up to 0.019 in. (0.5 mm) in depth
  • Up to 0.08 in. (2 mm) in width
  • Up to 0.39 in. (10 mm) in cumulated length.
C.Nicks or dents on the convex (suction) surface.
  • Up to 0.008 in. (0.2 mm) in depth
  • Up to 0.08 in. (2 mm) in width
  • Up to 0.39 in. (10 mm) in cumulated length.
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • Up to 0.019 in. (0.5 mm) in depth
  • Up to 0.08 in. (2 mm) in width
  • Up to 0.39 in. (10 mm) in cumulated length.
D.Scratches on the concave (pressure) surface if depth is up to 0.004 in. (0.1 mm).
  • Any number
  • Any length.
E.Scratches on the concave (pressure) surface if depth is more than 0.004 in. (0.1 mm) and up to 0.008 in. (0.2 mm).
  • Any number
  • Up to 1.18 in. (30 mm) in length
  • Up to 9.05 in. (230 mm) in cumulated length.
F.Scratches on the concave (pressure) surface if depth is more than 0.008 in. (0.2 mm) and up to 0.02 in. (0.5 mm).
Not permitted.
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • One scratch permitted
  • Up to 2.36 in. (60 mm) in length.
G.Scratches on the convex (suction) surface if depth is up to 0.004 in. (0.1 mm).
  • Any number
  • Any length.
H.Scratches on the convex (suction) surface if depth is more than 0.004 in. (0.1 mm) and up to 0.008 in. (0.2 mm).
  • Any number
  • Up to 1.18 in. (30 mm) in length
  • Up to 9.05 in. (230 mm) in cumulated length.
J.Scratches on the convex (suction) surface if depth is more than 0.008 in. (0.2 mm) and up to 0.02 in. (0.5 mm).
Not permitted.
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • One scratch permitted
  • Up to 2.36 in. (60 mm) in length.
22.Visual examination of the fan blade (1) dovetail and shank (if the fan blade (1) is removed from the fan disk) in Areas N and T.

A.Nicks or dents on the LE and the TE radius over 1.38 in. (35 mm) from the bottom root.
  • Any number
  • Up to 0.04 in. (1 mm) in depth
  • Up to 0.0062 in.2 (4 mm2) in damaged section
  • Any length.
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • One indication permitted per radius
  • Up to 0.08 in. (2 mm) in depth
  • Up to 0.0217 in.2 (14 mm2) in damaged section
  • Any length.
B.Nicks or dents on the LE and the TE radius up to 1.38 in. (35 mm) from the bottom root.
  • Any number
  • Up to 0.02 in. (0.5 mm) in depth
  • Up to 0.00155 in.2 (1 mm2) in damaged section
  • Any length.
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • Up to 0.04 in. (1.0 mm) in depth
  • Up to 0.0062 in.2 (4 mm2) in damaged section
  • Any length.
C.Nicks or dents on LE and TE radius bottom end (0 in. (0.00 mm) to 0.11 in. (2.79 mm) from root).
  • One indication permitted per radius
  • Up to 0.019 in. (0.48 mm) in depth
  • Up to 0.098 in. (2.49 mm) in length
  • Up to 0.07 in. (1.78 mm) in width.
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • One indication permitted per radius
  • Up to 0.03 in. (0.76 mm) in depth
  • Up to 0.11 in. (2.79 mm) in length
  • Up to 0.098 in. (2.49 mm) in width.
D.Scratches on the LE and the TE radius.
  • One indication permitted per radius
  • Up to 0.007 in. (0.18 mm) in depth
  • Up to 0.78 in. (19.81 mm) in length.
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • One indication permitted per radius
  • Up to 0.019 in. (0.48 mm) in depth
  • Up to 1.96 in. (49.78 mm) in length.
E.Nicks or dents on the LE surface.
  • Up to 0.02 in. (0.5 mm) in depth
  • Up to 0.062 in.2 (40 mm2) in cumulated surface.
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • Up to 0.02 in. (0.5 mm) in depth
  • Up to 0.124 in.2 (80 mm2) in cumulated surface.
F.Scratches on the LE surface.
  • Two indications permitted
  • Up to 0.007 in. (0.18 mm) in depth
  • Up to 0.78 in. (19.81 mm) in length.
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • One indication permitted
  • Up to 0.019 in. (0.48 mm) in depth
  • Up to 0.78 in. (19.81 mm) in length.
G.Nicks, dents on the TE surface.
  • Up to 0.02 in. (0.5 mm) in depth
  • Up to 0.062 in.2 (40 mm2) in cumulated surface.
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • Up to 0.02 in. (0.5 mm) in depth
  • Up to 0.124 in.2 (80 mm2) in cumulated surface.
H.Scratches on the TE surface.
  • Up to 0.007 in. (0.18 mm) in depth
  • Up to 1.18 in. (29.97 mm) in length
  • Up to 3.93 in. (99.82 mm) in cumulated length.
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • Up to 0.019 in. (0.48 mm) in depth
  • Up to 1.57 in. (39.88 mm) in length
  • Up to 3.93 in. (99.82 mm) in cumulated length.
23.Visual examination of the fan blade (1) dovetail and shank (if the fan blade (1) is removed from the fan disk) in Area P.


A.Cracks, tears, fiber breakage.
Not serviceable.

B.Nicks, dents.
  • Up to 0.0098 in. (0.25 mm) in depth
  • Up to 0.01 in.2 (6.45 mm2) per single surface
  • Minimum distance between two nicks: 0.40 in. (10.16 mm).
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • Up to 0.019 in. (0.48 mm) in depth
  • Up to 0.03 in.2 (19.35 mm2) per single surface
  • Minimum distance between two nicks 0.20 in. (5.08 mm).
C.Scratches if depth is up to 0.004 in. (0.1 mm).
  • Any number
  • Any length.
D.Scratches if depth is more than 0.004 in. (0.1 mm) and up to 0.008 in. (0.2 mm).
  • Up to 1.97 in. (50 mm) in length
  • Up to 9.84 in. (250 mm) in cumulated length.
E.Scratches if depth is more than 0.008 in. (0.2 mm) and up to 0.02 in. (0.5 mm).
Not permitted.
The continue-in-service limit of 100 cycles is permitted with the criteria:
  • Up to 3.15 in. (80 mm) in length
  • Up to 9.84 in. (250 mm) in cumulated length.
24.Visual examination of the fan blade (1) dovetail and shank (if the fan blade (1) is removed from the fan disk) in Area Q:
NOTE: Area Q is defined as the LE composite surface of the fan blade (1) shank and root between the metallic LE adhesive (upper limit) and the LE wear strip (lower limit).
NOTE: Radius are not a part of Area Q.


A.Decohesion on the LE face concave (pressure) side.
Any amount, any length if width of the surrounding area does not exceed 0.11 in. (3 mm).
One surrounding area permitted.
Radially, the surrounding area cannot have contact with the upper and with the lower limit of Area Q.

B.Decohesion on LE face convex (suction) side.
Any amount, any length if width of the surrounding area does not exceed 0.11 in. (3 mm).
One surrounding area permitted.
Radially, the surrounding area cannot have contact with the upper and with the lower limit of Area Q.

25.Visual examination of the fan blade (1) dovetail and shank (if the fan blade (1) is removed from the fan disk) in Area R.


A.Micro-cracking in the resin on the concave (pressure) surface and the convex (suction) surface.
Any amount.
26.Visual examination of the fan blade (1) dovetail and shank (if the fan blade (1) is removed from the fan disk) in Area S.


A.Decohesion on the concave (pressure) surface and the convex (suction) surface.
Any amount.

27.Visual examination of the wear strips of the fan blade (1) dovetail (if the fan blade (1) is removed from the fan disk).


A.Loose, missing.
Serviceable if missing material is not more than 0.03 in. (0.76 mm) from one of the edges.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
B.Wear.
Any amount if not worn through to the composite blade surface and the worn area is not frayed.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
C.Nicks, dents, scratches.
Any amount if the composite is not visible and the wear strips surface not frayed.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
D.Frayed, disbonded corners.
Serviceable if the frayed or disbonded area is not more than 0.11 in. (2.79 mm) across the diagonal corner of the wear strip.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
E.Frayed, disbonded edges.
Serviceable if is not more than 0.03 in. (0.76 mm) from one of the edges.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
F.Discoloration.
Serviceable.

28.Visual examination of the platform wear strips area if the fan blade (1) is not removed.


A.Loose, missing on visible suction side.
Permitted if the missing material is not more than 0.03 in. (1 mm) from the upper edges.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
B.Wear up to the composite material or loose, missing on the visible-pressure side platform wear-strip area.
Serviceable up to 5.70 in. (145 mm) wear strip length.
The continue-in-service limit of 100 cycles is permitted with the criteria: Up to 7.79 in. (198 mm). See repair (Ref. AMM TASK 72-21-20-300-801).
C.Wear on the visible-suction side platform wear-strip area.
Any amount, if not worn through to the composite blade surface and the worn area is not frayed.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
D.Nicks, dents, scratches.
Any amount, if not worn through to the composite blade surface and if the dented area is not frayed.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
E.Frayed, disbonded corners.
Permitted if the frayed or disbonded area is not more than 0.11 in. (3 mm) across the diagonal corner of the wear strip.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
F.Frayed, disbonded edges on visible pressure side.
Permitted if is not more than 0.03 in. (1 mm) from one of the edges.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount. See repair (Ref. AMM TASK 72-21-20-300-801).
G.Frayed, disbonded edges on visible suction side.
Permitted if is not more than 0.03 in. (1 mm) from one of the edges.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
H.Discoloration.
Permitted.

29.Visual examination of the platform wear strips if fan blade (1) is removed.

A.Loose, missing on visible suction side.
Permitted if the missing material is not more than 0.03 in. (1 mm) from one of the edges.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
B.Loose, missing on visible pressure side.
Wear up to the composite material or loose, missing on the visible-pressure side platform wear-strip area.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount. See repair (Ref. AMM TASK 72-21-20-300-801).
C.Wear on the upper-pressure-side platform wear-strip area.
Serviceable up to 5.70 in. (145 mm) wear strip length.
The continue-in-service limit of 100 cycles is permitted with the criteria: Up to 7.79 in. (198 mm). See repair (Ref. AMM TASK 72-21-20-300-801).
D.Wear on the suction and pressure-side platform wear-strip area except on upper-pressure side wear-strip area.
Any amount, if not worn through to the composite blade surface and the worn area is not frayed.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
E.Nicks, dents, scratches.
Any amount, if not worn through to the composite blade surface and if the dented area is not frayed.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
F.Frayed, disbonded corners.
Permitted if the frayed or disbonded area is not more than 0.11 in. (3 mm) across the diagonal corner of the wear strip.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
G.Frayed, disbonded edges on visible pressure side.
Permitted if is not more than 0.03 in. (1 mm) from one of the edges.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount. See repair (Ref. AMM TASK 72-21-20-300-801).
H.Frayed, disbonded edges on visible suction side.
Permitted if is not more than 0.03 in. (1 mm) from one of the edges.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
J.Discoloration.
Permitted.

30.Visual examination of the LE and the TE wear strips of the fan blade (1) (if the fan blade (1) is removed from the fan disk).


A.Loose, missing.
Serviceable if the missing material is not more than 0.03 in. (0.76 mm) from one of the edges.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
B.Wear.
Any amount if not worn through to the composite blade surface and the worn area is not frayed.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
C.Nicks, dents, scratches.
Any amount if the composite is not visible and the wear strips surface not frayed.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
D.Frayed, disbonded corners.
Serviceable if the frayed or disbonded area is not more than 0.11 in. (2.79 mm) across the diagonal corner of the wear strip.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
E.Frayed, disbonded edges.
Serviceable if is not more than 0.03 in. (0.76 mm) from one of the edges.
The continue-in-service limit of 100 cycles is permitted with the criteria: Any amount.
F.Discoloration.
Serviceable.

Table - Visual Examination of the Fan Blade
Subtask 72-21-20-280-052-A
B. Tap Test of the Metallic LE
CAUTION: BE CAREFUL WHEN YOU DO THE TAP TEST. USE THE APPLICABLE TOOL. IF YOU DO NOT OBEY THIS PRECAUTION, YOU CAN CAUSE DAMAGE TO THE LEADING EDGE AND THE FAN BLADES.
   (1) If necessary, following visual examination, do the tap test as follows with an aluminum mallet:
NOTE: Use the mallet that weights between 1.59 oz (45 g) and 3.53 oz (100 g) to do the tap test of the metallic LE. You can use a mallet from the figure or use an equivalent mallet, that suits the specification above.
F Metallic Leading Edge Nose and Sidewall
     (a) Tap on each side (convex and concave) of the fan blade (1).
     (b) Tap from the end of the metallic LE nose to the metallic LE sidewalls.
     (c) Tap from the bottom of the metallic LE to the tip.
NOTE: If a solid click is heard, the area is bonded. If a hollow sound is heard, the area is disbonded.
   (2) Make a mark around each disbonded area on the metallic LE with a PENCIL SPM 701021.
   (3) Refer to Para. 4.A. for maximum serviceable limits.
5. Close-up
Subtask 72-21-20-942-055-A
A. Close Access
   (1) Make sure that the work area is clean and clear of tools and other items.
   (2) Remove the MAT - PROTECTIVE from the lower half of the inlet cowl.
   (3) Remove the WARNING NOTICE(S).
[Rev.10 from 2021] 2026.04.01 02:51:37 UTC
"Aviabrain" 2025