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

TASK 72-21-01-220-802-A
Detailed Visual Inspection (DVI) of the Fan Case Rubstrip

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

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

WARNING: MAKE SURE THAT THE ENGINE SHUTDOWN OCCURRED NOT LESS THAN FIVE MINUTES BEFORE YOU DO THIS PROCEDURE. 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 rubstrip.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	MAT - PROTECTIVE
No specific	1	MICROMETER - DEPTH
636-1100-3GSE	1	INLET COWL PROTECT COVER
PWA107214	1	GAGE CHECKING-FAN BLADE TIP CLEARANCE
PWA29156	1	GAGE-FAN CASE RUB STRIP

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.P05-416)	chalk, white

C. Work Zones and Access Panels

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

D. Referenced Information

REFERENCE	DESIGNATION
TASK 71-00-00-860-833-A	Procedure to Prevent Engine Motoring
TASK 72-21-01-300-802-A	Repair the Fan Case Rubstrip
Detailed Visual Inspection (DVI) of the Fan Case Rubstrip

3. Job Set-up
Subtask 72-21-01-941-052-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).

4. Procedure

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

Subtask 72-21-01-220-051-A ** ON A/C NOT FOR ALL

A. Detailed Visual Inspection (DVI) of the Fan Case Rubstrip
(1) Put an 636-1100-3GSE INLET COWL PROTECT COVER or equivalent MAT - PROTECTIVE inside the engine inlet cowl.
(2) Do a DVI of the fan case rubstrip for voids, holes, pits and surface damage. Refer to Table 601.

Detailed Visual Inspection (DVI) of the Fan Case Rubstrip ** ON A/C NOT FOR ALL

(a) If you find axial cracking that follows rubstrip honeycomb ribbon pattern, contact Pratt & Whitney.
(3) Measure the fan case rubstrip for excessive wear by one of the two methods, A or B.
(a) Method A (fan blade tip clearance). See the sheet 1 of the figure.

Detailed Visual Inspection (DVI) of the Fan Case Rubstrip ** ON A/C NOT FOR ALL

1 Use the PWA107214 GAGE CHECKING-FAN BLADE TIP CLEARANCE or equivalent to measure the fan case rubstrip as follows:

CAUTION: DO NOT USE A MARKER OTHER THAN CHALK. IF YOU DO, DAMAGE TO THE FAN CASE RUBSTRIP CAN OCCUR.

a Use P05-416chalk, white and make a mark on the rubstrip at eight equally spaced locations approximately 6.1 in. (154.94 mm) axially rearward from the fan case rubstrip forward edge (center of the segment of the fan rub path).
b Select a fan blade and pull (by the aft edge at mid-span) the blade forward against the blade lock on the front hub.
c Use the PWA107214 GAGE CHECKING-FAN BLADE TIP CLEARANCE or equivalent and measure the clearance between the blade tip and the marks at the eight locations as follows:

Measure perpendicular to the face of the fan blade at approximately the mid-chord position.
Turn the fan blade assembly as necessary and use the same fan blade at all the positions.
Make sure that the fan blade is kept pulled forward during all measurements.
Record the clearance measurements at all the positions.

d If the blade clearance is 0.205 in. (5.207 mm) or less at all the clock positions (one to eight), the rubstrip is serviceable.
e If the blade tip clearance at one or more of the clock positions (one through eight) is more than 0.205 in. (5.207 mm), use Table 602 and calculate the average clearance for each group.

Compare the average clearance of the applicable group(s) with the limits in method A. Refer to Table 601.

(b) Method B (rubstrip wear hole depth measurement). See the sheet 2 of the figure.

Detailed Visual Inspection (DVI) of the Fan Case Rubstrip ** ON A/C NOT FOR ALL

1 Check the wear depth of the fan case rubstrip wear holes with the PWA29156 GAGE-FAN CASE RUB STRIP or MICROMETER - DEPTH, as follows:
a Find the 24 wear depth holes, eight groups of three, equally spaced along the inner diameter surface of the fan case rubstrip.
b Measure the wear holes at clock positions one to eight, three holes at each location, with the PWA29156 GAGE-FAN CASE RUB STRIP or a MICROMETER - DEPTH.
c If using the PWA29156 GAGE-FAN CASE RUB STRIP, set the gage to zero on the detail set master.
d Record the depth of each wear hole and use the following criteria.
e If all the wear hole depth measurements are 0.146 in. (3.708 mm) or more, the rubstrip is serviceable.
f If more measurement is less than 0.146 in. (3.708 mm), do the following:
g Take an average of the hole and the other two holes at the clock location. If the average of the three holes is in limits, the holes in that location are acceptable. If the average of the three holes are not in limits, go to step 4.A.(3).(b).1_.h_.
h Use Table 602 and calculate the average wear hole depth for each group. See Table 601 for limits.

Table 601: Fan Case Rubstrip Inspection Criteria

EXAMINE	DAMAGE	DISPOSITION
Fan case rubstrip for:
Circumferential scoring	All quantities	Permitted for continued service.
Damage (voids, holes, pits or missing material) that does not show the septum layer or the honeycomb material.	All quantities 0.125 in. (3.175 mm) or less in diameter	Permitted for continued service.
	All quantities less than 1.5 in. (38.100 mm) in diameter. Total area of missing material is not more than 15 in.2 (9677.400 mm2).	Permitted for continued service.
	A maximum of five areas less than 10 in. (254.00 mm) circumferential and 3 in. (76.20 mm) axial, if the distance between them is equal to the maximum dimension of the nearest damaged area.	Permitted for continued service.
	A maximum of one missing rubstrip segment, not more than 20.7 in. (0.53 m) circumferential and 11.9 in. (302.26 mm) axial.	Permitted for 50 flight hours or 20 cycles (whichever occurs first), then remove the engine or repair (Ref. AMM TASK 72-21-01-300-802).
	A maximum of two missing non-adjacent rubstrip segments, not more than 41.4 in. (1.05 m) circumferential and 11.9 in. (302.26 mm) axial.	Permitted for five cycles maximum service, then remove the engine or repair (Ref. AMM TASK 72-21-01-300-802).
	Two missing adjacent rubstrip segments, or three or more non-adjacent missing rubstrip segments.	Not permitted. Remove the engine before next flight.
	Local damage in one location not more than 246.33 in.2 (1589.22 cm2) for a total area of 492.66 in.2 (3178.45 cm2), 0.25 in. (6.35 mm) minimum from the center of a wear hole. If the damaged areas are more than 1.500 in. (38.10 mm)in diameter, there must be a distance between them equal to the maximum dimension of the nearest damaged area.	Permitted for five cycles maximum service, then remove the engine or repair (Ref. AMM TASK 72-21-01-300-802).
Damage that shows the septum sheet layer or that extends through the septum sheet layer or into the honeycomb material.	Average fan blade tip clearance for each group is not more than 0.205 in. (5.207 mm).	Permitted.
	A maximum of 1.500 in. (38.100 mm) in diameter.	Permitted for five cycles maximum service, then remove the engine or repair.
	More than 1.500 in. (38.100 mm) in diameter.	Not permitted. Remove the engine before next flight.
Rubstrip wear (Method A, fan blade tip clearance)	Average fan blade tip clearance for each group is not more than 0.205 in. (5.207 mm).	Permitted.
	Average fan blade tip clearance for each group is more than 0.205 in. (5.207 mm) and wear does not extend through the septum sheet layer at all locations.	Permitted for five cycles maximum service, then remove the engine or repair (Ref. AMM TASK 72-21-01-300-802).
	Rubstrip wear that extends through the septum sheet layer and into the honeycomb material.	Not permitted. Remove the engine before next flight.
Rubstrip wear (Method B, wear hole depth measurement)	Average wear hole depth for each group is 0.146 in. (3.708 mm) or more.	Permitted.
	Average wear hole depth for each group is less than 0.146 in. (3.708 mm) and wear at all locations does not extend through the septum sheet layer and into the honeycomb material.	Permitted for five cycles maximum service, then remove or repair (Ref. AMM TASK 72-21-01-300-802).
	All quantities of wear that extends through the septum sheet layer and into the honeycomb material.	Not permitted. Remove the engine before next flight.

Table 602: Fan Case Rubstrip Group Positions

GROUP	POSITION
1	7, 8, 1
2	8, 1, 2
3	1, 2, 3
4	2, 3, 4
5	3, 4, 5
6	4, 5, 6
7	5, 6, 7
8	6, 7, 8

(4) Remove the MAT - PROTECTIVE from the fan cowl.
(5) Examine the assembly for foreign objects, damage, and correct assembly.

5. Close-up
Subtask 72-21-01-860-052-A ** ON A/C NOT FOR ALL

A. Put the aircraft back to its initial configuration.
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 02:48:23 UTC