Removal of the Aft Acoustical Panels [CFMB]

TASK 72-23-00-000-026-A
Removal of the Aft Acoustical Panels

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

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
FIN: 1000EM1 ** ON A/C NOT FOR ALL
FIN: 1000EM2 ** ON A/C NOT FOR ALL

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

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

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.CP2242)	RTV 732

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
210	CKPT,FWD COMPT BHD TO FLT COMPT BULKHEAD
400	POWER PLANT, NACELLES AND PYLONS
FOR [1000EM1] (ENGINE-1)
437AL, 438AR, 451AL, 452AR
FOR [1000EM2] (ENGINE-2)
447AL, 448AR, 461AL, 462AR

D. Referenced Information

REFERENCE	DESIGNATION
TASK 71-13-00-010-040-B	Opening of the Fan Cowl Doors
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
Aft Acoustical Panel (Configuration 1 and Configuration 2)

3. Job Set-up
Subtask 72-23-00-941-074-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 72-23-00-010-085-A ** ON A/C NOT FOR ALL

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

Subtask 72-23-00-040-062-A ** ON A/C NOT FOR ALL

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

Subtask 72-23-00-010-095-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 72-23-00-020-062-A ** ON A/C NOT FOR ALL

A. Remove the Aft Acoustical Panels as follows (typical, any panel):

CAUTION: IF YOU USE A PNEUMATIC OR ELECTRICAL SCREWDRIVER TO UNTORQUE AND LOOSEN ALL ACOUSTICAL PANEL SCREWS, MAKE SURE THAT THE SCREWDRIVER SPEED IS NOT MORE THAN 200 RPM. IF YOU DO NOT OBEY THIS INSTRUCTION, YOU CAN CAUSE DAMAGE TO THE ACOUSTICAL PANEL.

(1) Remove the screws (130) that attach the aft acoustical panel (140).

NOTE: If one screw is found untorqued, it must be discarded and replaced for re-installation.

(2) Remove the nuts (155) and the screws (150).

PRE SB 72-0071 (Configuration One)

(3) Disengage the panel (140) from the case and thrust reverser adapter-ring.
(a) Remove the panel (140) which comes with its two lateral bonded seals.

END PRE SB 72-0071 (Configuration One)

POST SB 72-0071 (Configuration Two)

(4) Disengage the panel (140) from the case and thrust reverser adapter-ring.
(a) Remove the panel (140).

NOTE: This panel will come without its U-shaped seal (145).

(b) Let the seal (145) squeezed between the two struts and the adjacent aft acoustical panels that "frame" the panel you remove.
(c) Remove the seal (145) and thus, the two adjacent panels, only if this seal is badly damaged.

END POST SB 72-0071 (Configuration Two)

(5) Remove the RTV 732 (Material No.CP2242) which remains on the aft acoustical panels.

[Rev.10 from 2021] 2026.04.01 02:41:32 UTC