Visual Inspection of the N1 Sensor [CFML]

TASK 77-11-05-210-801-A
Visual Inspection of the N1 Sensor

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

REFERENCE	QTY	DESIGNATION
No specific	1	LIGHT SOURCE - INSPECTION
No specific	1	MIRROR - INSPECTION, FLEXIBLE
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, 452AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL, 448AR, 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 72-24-01-000-801-A	Removal of Segment Shrouds 1 thru 5
TASK 72-24-01-400-801-A	Installation of Segment Shrouds 1 thru 5
TASK 77-11-05-000-801-A	Removal of the N1 Sensor
TASK 77-11-05-400-801-A	Installation of the N1 Sensor
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 N1 Sensor

3. Job Set-up
Subtask 77-11-05-941-052-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 WARNING NOTICE(S) in position to tell persons not to operate:

The ENG/MODE selector switch, and
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 77-11-05-010-054-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

Subtask 77-11-05-040-052-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 maintenance (Ref. AMM TASK 78-30-00-040-809).

Subtask 77-11-05-010-055-A

D. Open the right thrust-reverser cowl-door (Ref. AMM TASK 78-36-00-010-806):
(1) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
452AR
(2) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
462AR

4. Procedure
Subtask 77-11-05-210-050-A

A. Visual Inspection of the N1 Sensor
(1) Remove the segment shroud 2 (Ref. AMM TASK 72-24-01-000-801).
(2) Remove and disconnect the connector from the N1 sensor, if need (Ref. AMM TASK 77-11-05-000-801).
(3) Do the visual inspection of the N1 sensor (1) for the indications that follow:

NOTE: You can use a LIGHT SOURCE - INSPECTION and a MIRROR - INSPECTION, FLEXIBLE to perform this inspection.

Table 1 : Visual inspection of surfaces A, B, E, F, FF, G, GG, H, HH (Visible surfaces), M, S and T

INSPECT/CHECK	MAXIMUM SERVICEABLE LIMITS	REMARKS
Cracks, Dents, Tear, Nicks, Scoring/Scratches, Erosion/Peening and Corrosion	Not serviceable	Replace the N1 sensor (Ref. AMM TASK 77-11-05-000-801) and (Ref. AMM TASK 77-11-05-400-801).
Deposits	Serviceable with identification can be readable with visual and optical device

Table 2 : Zone description

ZONE	DESCRIPTION
A	Connector Housing
B	Mounting Flange
E	Bonding Strap
F	Lid
FF	Connector Gasket
G	Lid fixings
GG	Connector Gasket
H	Bonding Strap Fixings
HH	Connector Gasket
M	Attachment Fixings
S	Connector plate
T	Connector

(4) Install and connect the N1 sensor (Ref. AMM TASK 77-11-05-400-801).
(5) Install the segment shroud 2 (Ref. AMM TASK 72-24-01-400-801).

5. Close-up
Subtask 77-11-05-410-052-A

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

Subtask 77-11-05-440-051-A

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

Subtask 77-11-05-410-053-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 WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.02 06:37:51 UTC