Detailed Inspection of Pack Air Check Valves Flappers for Condition and Operation

TASK 21-52-43-210-001-A
Detailed Inspection of Pack Air Check Valves Flappers for Condition and Operation

ZONE: 130
ZONE: 190
FIN: 15HM
FIN: 16HM

1. Reason for the Job
Refer to the MPD TASK: 215000-02
DETAILED INSPECTION OF PACK AIR CHECK VALVES FLAPPERS FOR CONDITION AND OPERATION
2. Job Set-up Information
A. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
130	FWD CARGO COMPT AFT BULKHEAD OF AVNCS COMPT TO FWD PRESSURE BULKHEAD OF WING CENTER BOX
190	BELLY FAIR, AIR CONDITIONING & HYD COMPT

B. Referenced Information

REFERENCE	DESIGNATION
TASK 21-52-43-000-001-A	Removal of the Pack Downstream Check-Valves
TASK 21-52-43-400-001-A	Installation of the Pack Downstream Check-Valves

3. Job Set-up
Subtask 21-52-43-020-053-A

A. Remove the pack downstream check-valve (Ref. AMM TASK 21-52-43-000-001).

4. Procedure
Subtask 21-52-43-210-052-A

A. Inspection of the Check Valve (P/N 769A0000-01 and 769A0000-02)
(1) Make sure that the check valve is clean.
(2) Do a visual inspection of the valve-flap and its seat, the hinge pin and the return spring of the valve-flap for signs of cracks, dents, marks or corrosion.
(3) Make sure that the valve-flap operates correctly on its hinge pin. To do this, move it with your hand. Also make sure that the valve-flap touches its seat correctly.

Subtask 21-52-43-210-053-A

B. Inspection of the Check Valve (P/N 769B0000-01 and P/N 769B0000-02)
(1) Make sure that the check valve is clean.
(2) Do a visual inspection of the valve-flap and its seat and the hinge pin for signs of cracks, dents, marks or corrosion.
(3) Make sure that the valve-flap operates correctly on its hinge pin. To do this, move it with your hand. Also make sure that the valve-flap touches its seat correctly.

5. Close-up
Subtask 21-52-43-420-052-A

A. Install the pack downstream check-valve (Ref. AMM TASK 21-52-43-400-001).

[Rev.10 from 2021] 2026.04.02 06:11:32 UTC