Borescope Inspection of the Inner Cowl Bolts of the Combustion Chamber [CFMB]

TASK 72-42-00-290-007-A
Borescope Inspection of the Inner Cowl Bolts of the Combustion Chamber

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)
856A1321	1	FIBERSCOPE SET
856A1322	1	BORESCOPE-LIGHT SOURCE SET
856A1323	1	MONITOR, RESOLUTION BORESCOPE

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 73-11-40-000-002-A	Removal of the Fuel Nozzle for SAC Engines
TASK 73-11-40-000-002-A-01	Removal of the Fuel Nozzle for DAC Engines
TASK 73-11-40-400-002-A	Installation of the Fuel Nozzle for SAC Engines
TASK 73-11-40-400-002-A-01	Installation of the Fuel Nozzle for DAC Engines
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
NTM 720000

3. Job Set-up
Subtask 72-42-00-941-059-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 72-42-00-010-080-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)

Subtask 72-42-00-040-059-A ** ON A/C NOT FOR ALL

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

Subtask 72-42-00-010-081-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 72-42-00-010-082-A ** ON A/C NOT FOR ALL

A. Remove parts before borescope inspection.
(1) Select fuel nozzles to remove that will allow access to the outer liner area to be inspected.
(2) Remove the fuel nozzles (Ref. AMM TASK 73-11-40-000-002)

Subtask 72-42-00-290-066-A ** ON A/C NOT FOR ALL

B. Do a borescope inspection.
(1) Use the 856A1323 MONITOR, RESOLUTION BORESCOPE (856A1323G01) to make sure borescope and the light source are serviceable. See the Non Destructive Test Manual for this procedure NTM 720000.
(2) Connect the fiber light cable to the 856A1321 FIBERSCOPE SET (856A1321P01 or 856A1321P03 or 856A1321P06) and to the port on the 856A1322 BORESCOPE-LIGHT SOURCE SET (856A1322P03, P04, or P07).
(3) Put the fiberscope of the 856A1321 FIBERSCOPE SET (856A1321P01 or 856A1321P03 or 856A1321P06) into the fuel nozzle ports and turn on the light source of 856A1322 BORESCOPE-LIGHT SOURCE SET (856A1322P03, or P04).
(4) Adjust the borescope equipment to obtain maximum clarity of view.
(5) Inspect the following:

INSPECT/CHECK	MAXIMUM SERVICEABLE LIMITS	REMARKS
1.Inner side of inner cowl for:
A.Missing bolts	Not serviceable	See limit extensions
B.Loose bolts	Not serviceable	See limit extensions
C.Cracked bolt tack welds	Not serviceable	See limit extensions

(6) When the inspection is complete, turn off the light source and remove the fiberscope.

Subtask 72-42-00-410-078-A ** ON A/C NOT FOR ALL

C. Install the fuel nozzles (Ref. AMM TASK 73-11-40-400-002).

5. Close-up
Subtask 72-42-00-410-076-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
(3) Remove the access platform(s).

Subtask 72-42-00-440-059-A ** ON A/C NOT FOR ALL

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

Subtask 72-42-00-410-077-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 WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 02:42:46 UTC