Detailed Visual Inspection (DVI) of the Fan Case External Surfaces [PW11]

TASK 72-21-00-220-801-A
Detailed Visual Inspection (DVI) of the Fan Case External Surfaces

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

ZONE: 400

1. Reason for the Job
Use this procedure to do a detailed visual inspection (DVI) of the fan case external surfaces.
For more information about the fan case, refer to 72-21-00-00
CONF 21 - FAN CASE - DESCRIPTION AND OPERATION.
Some conditions are permitted for continued service without repair, but it is usually better to remove this damage with a blend repair. The sharper the surface damage, the more important it is to do a blend repair of the area. For surface damage on flanges and metal surfaces that is within the limits permitted for continued service, do a fluorescent penetrant inspection of the nick, dent or scratch for cracks by SPOP 70, normal sensitivity. Refer to task AMM 70-25-00-910-80100. If cracks are not detected, the surface damage is permitted for continued service. Contact Pratt & Whitney if cracks are detected. If surface damage is on the front flange plate or on the aft ring support (details made of aluminum alloy), it is required to touch-up the damaged/repaired area by chromate conversion coating per SPOP 42. Refer to task AMM 70-28-00-910-80300 before you permit for continued service.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 2M (6 FT)
No specific	1	LIGHT SOURCE - ULTRA-VIOLET
No specific	1	MICROMETER - DEPTH
PWA115424	3	WEDGE, HAND

B. Work Zones and Access Panels

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

C. Referenced Information

REFERENCE	DESIGNATION
TASK 71-00-00-860-833-A	Procedure to Prevent Engine Motoring
TASK 71-00-51-000-802-A	Removal of the Power Plant (Bootstrap Method)
TASK 71-00-51-000-802-A-01	Removal of the Power Plant (JacXson Method)
TASK 71-00-51-400-802-A	Installation of the Power Plant (Bootstrap Method)
TASK 71-00-51-400-802-A-01	Installation of the Power Plant (JacXson Method)
TASK 71-13-00-010-802-A	Opening of the Fan Cowl Doors
TASK 71-13-00-410-802-A	Closing of the Fan Cowl Doors
TASK 72-21-00-300-805-A	Blend the Surface Damage of the Fan Case Assembly Metal Area
TASK 72-21-01-220-804-A	Detailed Inspection of the Engine Fan Case V-Groove
TASK 72-21-01-300-801-A	Repair the Fan Case V-Groove Air Seal
TASK 72-21-01-960-802-A	Replacement of the Fan Case Assembly Composite Studs
Detailed Visual Inspection (DVI) of the Fan Case External Surfaces

3. Job Set-up
Subtask 72-21-00-941-091-A ** ON A/C NOT FOR ALL

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

Subtask 72-21-00-010-066-A ** ON A/C NOT FOR ALL

B. Get Access
(1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-802).
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL, 438AR.
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR.
(2) Put the ACCESS PLATFORM 2M (6 FT) in position.

4. Procedure
Subtask 72-21-00-220-058-A ** ON A/C NOT FOR ALL

A. Detailed Visual Inspection (DVI) of the Fan Case External Surfaces

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

CAUTION: DO NOT USE FAN BLADE WEDGE TOOLS IN WINDS MORE THAN FIVE MILES PER HOUR. IF YOU DO NOT OBEY THIS INSTRUCTION, DAMAGE TO THE ENGINE CAN OCCUR.

(1) Install three PWA115424 WEDGE, HAND as necessary to stop fan blade windmill during this inspection and make sure that the red streamer is visible and exits the fan cowl.
(2) Use a MICROMETER - DEPTH and a LIGHT SOURCE - ULTRA-VIOLET as necessary when you do the visual inspection of the fan case outer surface for surface damage. Refer to Table 601 and see the sheet 1 of the figure.
(3) For a detailed visual inspection of the fan case outer V-groove, refer to (Ref. AMM TASK 72-21-01-220-804).
(4) Remove the three PWA115424 WEDGE, HAND, if necessary.

Table 601: Fan Case External Surfaces - Visual Inspection

EXAMINE	DAMAGE	DISPOSITION
All surfaces for:
Cracks	Any amount.	Not permitted. Replace the engine (Ref. AMM TASK 71-00-51-000-802) and (Ref. AMM TASK 71-00-51-400-802).
External composite surfaces for:
Nicks, dents, scratches, rubs and scuffs	All quantities not more than 0.010 in. (0.254 mm) depth, if the damages do not extend below the protective layer.	Permitted.
	More than 0.010 in. (0.254 mm) depth.	Not permitted. Replace the engine (Ref. AMM TASK 71-00-51-000-802) and (Ref. AMM TASK 71-00-51-400-802).
Delamination or peeling	All quantities.	Not permitted. Replace the engine (Ref. AMM TASK 71-00-51-000-802) and (Ref. AMM TASK 71-00-51-400-802).
Voids and surface porosities	All quantities, if void or porosity does not extend below the protective layer.	Permitted.
	If void or porosity extends below the protective layer.	Not permitted. Replace the engine (Ref. AMM TASK 71-00-51-000-802) and (Ref. AMM TASK 71-00-51-400-802).
Dry spots	All quantities not more than 1.00 in. (25.40 mm) diameter.	Permitted.
	More than 1.00 in. (25.40 mm) diameter.	Not permitted. Replace the engine (Ref. AMM TASK 71-00-51-000-802) and (Ref. AMM TASK 71-00-51-400-802).
Resin rich area	All quantities.	Permitted.
Wrinkle	All quantities not more than 0.05 in. (1.27 mm) depth and 3.9 in. (99.06 mm) length.	Permitted.
	More than 0.05 in. (1.27 mm) deep or 3.9 in. (99.06 mm) length.	Not permitted. Replace the engine (Ref. AMM TASK 71-00-51-000-802) and (Ref. AMM TASK 71-00-51-400-802).
Surface discoloration	Black, gray, green or brown.	Permitted.
Other surface imperfections	All quantities if the damages do not extend below the protective layer.	Permitted.
	Damages that extend below the protective layer.	Not permitted. Replace the engine (Ref. AMM TASK 71-00-51-000-802) and (Ref. AMM TASK 71-00-51-400-802).
Composite fan case flange, forward shell, aft shell and containment area for:
Resin cracks	Not more than 0.02 in. (0.51 mm) crack opening width and 0.02 in. (0.51 mm) crack depth and crack does not extend below the protective layer.	Permitted.
	More than 0.02 in. (0.51 mm) crack opening width or 0.02 in. (0.51 mm) crack depth or crack extends below the protective layer.	Not permitted. Replace the engine (Ref. AMM TASK 71-00-51-000-802) and (Ref. AMM TASK 71-00-51-400-802).
Composite fan case forward shell, aft shell and containment area for:
Resin imperfections	All quantities not more than 0.50 in. (12.70 mm) diameter.	Permitted.
	More than 0.50 in. (12.70 mm) diameter.	Not permitted. Replace the engine (Ref. AMM TASK 71-00-51-000-802) and (Ref. AMM TASK 71-00-51-400-802).
Containment taper for:
Resin cracks	No crack opening and not more than 0.50 in. (12.70 mm) crack length and not more than 3.9 in. (99.1 mm)total length and crack does not extend below the protective layer.	Permitted.
	More than the limits above.	Not permitted. Replace the engine (Ref. AMM TASK 71-00-51-000-802) and (Ref. AMM TASK 71-00-51-400-802).
Resin imperfections	Any amount not more than 0.25 in. (6.35 mm) diameter.	Permitted.
	More than 0.25 in. (6.35 mm) diameter.	Not permitted. Replace the engine (Ref. AMM TASK 71-00-51-000-802) and (Ref. AMM TASK 71-00-51-400-802).
Flanges and metal surfaces in Area A and Area B for nicks, scratches and dents	Any amount up to 0.005 in. (0.127 mm) depth.	Permitted for continued service.
	Any amount more than 0.005 in. (0.127 mm) depth.	Contact Pratt & Whitney.
Flanges and metal surfaces in Area C for nicks, scratches and dents	Any amount up to 0.005 in. (0.127 mm) depth.	Permitted for continued service.
	Any amount up to 0.020 in. (0.508 mm) depth.	Not permitted. Remove the engine or repair the fan case (Ref. AMM TASK 72-21-00-300-805).
	Any amount more than 0.020 in. (0.508 mm) depth.	Contact Pratt & Whitney.
Aft ring support forward area for nicks, scratches and dents	Any amount up to 0.005 in. (0.127 mm) depth.	Permitted for continued service.
	Any amount up to 0.100 in. (2.54 mm) depth.	Not permitted. Remove the engine or repair the fan case (Ref. AMM TASK 72-21-00-300-805).
	Any amount more than 0.100 in. (2.54 mm) depth.	Contact Pratt & Whitney.
Flanges and metal surfaces in other areas (excluding fan case outer V-groove surface) for:
Nicks, scratches and dents
	Any amount not more than 0.005 in. (0.127 mm) depth.	Permitted for continued service.
	Any amount not more than 0.030 in. (0.762 mm) depth.	Not permitted. Remove the engine or repair the fan case (Ref. AMM TASK 72-21-00-300-805).
	More than 0.030 in. (0.762 mm) depth.	Contact Pratt & Whitney.
All flanges and metal surfaces, except closeout segments and flange segments, for:
Missing corrosion protection layer	Any amount.	Not permitted. Replace the engine within 50 flight hours or ten flight cycles or contact Pratt & Whitney (Ref. AMM TASK 71-00-51-000-802) and (Ref. AMM TASK 71-00-51-400-802).
Corrosion pits	Any amount.	Contact Pratt & Whitney.
V-groove seal for:
Loose or missing condition	Any amount.	Not permitted. Repair the fan case in five flight cycles (Ref. AMM TASK 72-21-01-300-801).
Cuts, cracks or tears	Any amount.	Not permitted. Repair the fan case in five flight cycles (Ref. AMM TASK 72-21-01-300-801).
Studs for:
Missing, loss of bond or damaged condition	Studs that are missing, have loss of bond or are damaged that you can use the mating part(s) to identify.	Not permitted. Repair the fan case (Ref. AMM TASK 72-21-01-960-802).
	Studs that are missing, have loss of bond or are damaged with locations that you cannot use the mating part(s) to identify.	Not permitted. Remove the engine or contact Pratt & Whitney before next flight (Ref. AMM TASK 71-00-51-000-802).
Bosses for:
Missing, loss of bond or damaged condition	All quantities.	Contact Pratt & Whitney.

(5) Examine the assembly for foreign objects, damage and correct assembly.

5. Close-up
Subtask 72-21-00-410-068-A ** ON A/C NOT FOR ALL

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Remove the access platform(s).
(3) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-802).
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL, 438AR.
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR.
(4) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 02:48:17 UTC