Visual inspection of the Low Pressure Turbine (LPT) Rear Frame [CFML]

TASK 72-59-04-200-801-A
Visual inspection of the Low Pressure Turbine (LPT) Rear Frame

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.

1. Reason for the Job
This procedure gives criteria for visual inspection of the LPT (Low Pressure Turbine) rear frame.

NOTE: The inspection criteria below are applicable after removal of high metal.

NOTE: You can use equivalent alternatives for standard tools, equipment and consumable materials.

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. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL, 438AR, 451AL, 452AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL, 448AR, 461AL, 462AR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 71-13-00-010-803-A	Opening of the Fan Cowl Doors
TASK 71-13-00-410-803-A	Closing of the Fan Cowl Doors
TASK 78-30-00-040-809-A	Deactivation of the Thrust Reverser System for Ground Maintenance
TASK 78-30-00-440-809-A	Reactivation of the Thrust Reverser System after Ground Maintenance
TASK 78-36-00-010-806-A	Opening of the Thrust Reverser Cowl Doors
TASK 78-36-00-410-806-A	Closing of the Thrust Reverser Cowl Doors
Visual Inspection of the Low Pressure Turbine (LPT) Rear Frame

3. Job Set-up
Subtask 72-59-04-941-050-A

A. Safety Precautions
(1) On the center pedestal, on ENG panel 115VU:
(a) Make sure that the ENG/MODE selector switch is in the NORM position.
(b) Make sure that the ENG/MASTER 1(2) control switch was in the OFF position not less than five minutes before you do this procedure.
(c) Put a WARNING NOTICE(S) in position to tell persons not to operate:

The ENG/MODE selector switch
The ENG/MASTER 1(2) control switch.

(2) On the ENG section of maintenance panel 50VU:
(a) Make sure that the ON legend of the FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put a WARNING NOTICE(S) in position to tell persons not to energize FADEC 1(2).

Subtask 72-59-04-010-050-A

B. Get Access
(1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-803):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL 448AR
(2) Put an ACCESS PLATFORM 1M(3 FT) in position.

Subtask 72-59-04-040-050-A

C. Deactivation of the Thrust Reverser System for Maintenance

WARNING: YOU MUST DEACTIVATE THE THRUST REVERSER BEFORE YOU DO WORK ON OR AROUND IT. IF YOU DO NOT, THE THRUST REVERSER CAN OPERATE ACCIDENTALLY AND CAUSE AN INJURY AND/OR DAMAGE.

(1) Do the deactivation of the thrust reverser system for ground maintenance (Ref. AMM TASK 78-30-00-040-809).

Subtask 72-59-04-010-051-A

D. Get Access
(1) Open the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-010-806):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
451AL 452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
461AL 462AR

4. Procedure
Subtask 72-59-04-210-050-A

A. Visual Inspection of Low Pressure Turbine (LPT) Rear Frame (1)

INSPECT/CHECK	MAXIMUM SERVICEABLE LIMITS	REMARKS
1.Visual inspection of all visible areas
A.Cracks	Not serviceable.
B.Coloration	Any coloration is acceptable.
2.Visual inspection of the aft outer flange, area Z
A.Nicks, dents, scratches	Any number if: - Not more than 0.98 in. (24.89 mm) in length - Not more than 0.0098 in. (0.25 mm) in depth - At least 1.0 in. (25.40 mm) apart.
3.Visual inspection of the aft inner flange, area Y
A.Nicks, dents, scratches	Any number if: - Not more than 0.98 in. (24.89 mm) in length - Not more than 0.0098 in. (0.25 mm) in depth - At least 1.0 in. (25.40 mm) apart.
4.Visual inspection of the clevis mounts areas L and K
A.Nicks, scores, scratches on lug faces	Not serviceable.
B.Disengaged, loose, missing bushings	Not serviceable.
5.Visual inspection of outer casing - clevis sectors No. 2 (3), No. 1 (4) and No. 15 (2)
A.Nicks and dents	Not serviceable.
B.Scratches	Not serviceable.
6.Visual inspection of outer casing - other sectors
A.Nicks, dents and scratches	Any number no more than 0.031 in. (0.79 mm) in depth and 1.00 in. (25.40 mm) minimum between two defects.
B.Cracks in welds	Not serviceable.
7.Visual inspection of the oil scavenge tube (5)
A.Cracks	Not serviceable.
B.Dents	Not serviceable.
C.Nicks, scratches, chafing, scores in straight section and bends	Not serviceable.
8.Visual inspection of tube and hose fitting nuts of the oil scavenge tube (5)
A.The condition of corners (9)	Any amount, if the correct torque can be kept.
B.Worn, bent, torn, missing fully or not thread (7)	Any amount, if the effective threads are not decreased by more than one after chasing.
C.Safetywire holes (8) tear-out	Serviceable, if there is one hole.
D.Circumferential scratches in areas A3 and C3	Any amount, if not more than 0.0051 in. (0.13 mm) in depth.
E.Circumferential scratches in area B3	Any amount, if not detected with a 0.0402 in. (1.02 mm) radius scriber.
F.Axial scratches in areas A3 and C3	Any amount, if not more than 0.0051 in. (0.13 mm) in depth.
G.Axial scratches in area B3	Not serviceable.
H.Nicks, pits in area C3	Any amount, if not more than 0.031 in. (0.79 mm) in depth.
J.Nicks, pits in areas A3 and B3	Not serviceable.
9.Visual inspection of stage 7 borescope port (10)
A.Cracks in welds	Not serviceable.

5. Close-up
Subtask 72-59-04-410-050-A

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-410-806):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
451AL 452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
461AL 462AR

Subtask 72-59-04-440-050-A

B. Do the reactivation of the thrust reverser system after ground maintenance (Ref. AMM TASK 78-30-00-440-809).

Subtask 72-59-04-410-051-A

C. Close Access
(1) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-803):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL 448AR
(2) Remove the access platform(s).
(3) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 02:53:59 UTC