Inspection of Aft Acoustical Panels [CFMB]

TASK 72-23-00-280-007-A
Inspection of Aft Acoustical Panels

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	ACCESS PLATFORM 1M(3 FT)
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

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

C. Referenced Information

REFERENCE	DESIGNATION
TASK 71-13-00-010-040-B	Opening of the Fan Cowl Doors
TASK 71-13-00-410-040-B	Closing of the Fan Cowl Doors
TASK 72-23-00-000-026-A	Removal of the Aft Acoustical Panels
TASK 72-23-00-300-044-A	Repair of Forward, Mid and Aft Acoustical Panels when Unbonded Cup
TASK 72-23-00-400-026-A	Installation of the Aft Acoustical Panels
TASK 72-23-00-400-044-A	Installation of Acoustical Panels Attachment Screw Locking
TASK 78-30-00-081-041-B	Make the Thrust Reverser Serviceable after Maintenance
TASK 78-30-00-481-041-B	Make the Thrust Reverser Unserviceable for Maintenance
TASK 78-36-00-010-040-B	Opening of the Thrust Reverser Doors
TASK 78-36-00-410-040-B	Closing of the Thrust Reverser Doors
Fan Acoustical Panels

3. Job Set-up
Subtask 72-23-00-941-095-A ** ON A/C NOT FOR ALL

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

Subtask 72-23-00-010-120-A ** ON A/C NOT FOR ALL

B. Get Access
(1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-040):
(2) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(3) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(4) Put an ACCESS PLATFORM 1M(3 FT) in position.

Subtask 72-23-00-040-073-A ** ON A/C NOT FOR ALL

C. Make the thrust reverser unserviceable (Ref. AMM TASK 78-30-00-481-041).

Subtask 72-23-00-010-121-A ** ON A/C NOT FOR ALL

D. Open the thrust reverser doors (Ref. AMM TASK 78-36-00-010-040):
(1) FOR [1000EM1] (ENGINE-1)
451AL 452AR
(2) FOR [1000EM2] (ENGINE-2)
461AL 462AR

4. Procedure
Subtask 72-23-00-350-060-A ** ON A/C NOT FOR ALL

A. Inspection of Aft Acoustical Panels

INSPECT/CHECK	MAXIMUM SERVICEABLE LIMITS	REMARKS
1.Aft acoustical panel cups
A.Dents, marks, indentations caused by screw head	No limits	(Ref. AMM TASK 72-23-00-400-026) for re-installation.
B.Pierced cups caused by screw head	Not serviceable	(Ref. AMM TASK 72-23-00-400-044)
C.Unbonded cups	Not serviceable	(Ref. AMM TASK 72-23-00-300-044)
D.Missing cups	Not serviceable	(Ref. AMM TASK 72-23-00-300-044)
PRE SB 72-071
2.Damaged or missing bonded seal(s)	No limits unless the whole seal is missing	Replace seal if missing
END OF PRE SB 72-071 POST SB 72-071
3.Mis-installed, badly damaged or missing U-shaped seal (removable)	Not serviceable	Install the seal correctly, or install a new U-shaped seal (Ref. AMM TASK 72-23-00-000-026) or (Ref. AMM TASK 72-23-00-400-026)
END OF SB 72-071
4.Missing panel	Not serviceable
5.Loose bolts	Not serviceable	Tighten bolts
6.Subsurface linear impressions or wrinkles	No limits	Serviceable criteria applied on new parts
7.Voids	Five per panels, 2 in. (50.8 mm) apart, 0.12 in. (3 mm) max. Dia 0.012 in. (0.3 mm) max. depth	Serviceable criteria applied on new parts
8.Defects in the protective coating (initial Tedlar film, or paint) such as:
A.Missing	No limits	Remove the loose material with a sharp blade
B.Defects (dents, nicks, tears, flaking) that let show the inner skin	No limits	Remove the loose material with a sharp blade
9.Inner skin defects, such as:
A.Superficial defects (dents, nicks, tears, impact marks) not through the skin	No limits with a total surface area less than 4 sq in. (2580 sq mm) per panel	Remove the loose material with a sharp blade
B.Defects (tears, cracks, punctures) through the skin	Not serviceable	Replace panel(s) (Ref. AMM TASK 72-23-00-000-026) and (Ref. AMM TASK 72-23-00-400-026)

5. Close-up
Subtask 72-23-00-410-111-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) Close the thrust reverser doors (Ref. AMM TASK 78-36-00-410-040):
(a) FOR [1000EM1] (ENGINE-1)
451AL 452AR
(b) FOR [1000EM2] (ENGINE-2)
461AL 462AR

Subtask 72-23-00-440-067-A ** ON A/C NOT FOR ALL

B. Make the thrust reverser serviceable (Ref. AMM TASK 78-30-00-081-041).

Subtask 72-23-00-410-112-A ** ON A/C NOT FOR ALL

C. Close Access
(1) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-040):
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(2) Remove the access platform(s).
(3) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 12:59:48 UTC