Removal of the Avionics Equipment Blowing and Extraction Ducts

TASK 21-26-42-000-002-A
Removal of the Avionics Equipment Blowing and Extraction Ducts

1. Reason for the Job
To do the maintenance of the strake on the right side of the fuselage.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE
No specific	AR	PLUG - BLANKING
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
128EG, 824

C. Referenced Information

REFERENCE	DESIGNATION
TASK 24-42-00-861-001-A	Energize the Ground Service Network from the External Power
TASK 52-41-00-010-002-A	Open the Avionics Compartment Doors for Access
TASK 53-12-13-000-001-A	Removal of the avionics compartment floor panels
Avionics Equipment Blowing-Duct
Avionics Equipment Extraction-Ducts

3. Job Set-up

CAUTION: USE ONLY THE GROUND SERVICE NETWORK TO SUPPLY ELECTRICITY BECAUSE THE AVIONICS VENTILATION SYSTEM IS NOT SERVICEABLE. IF YOU ENERGIZE THE AIRCRAFT ELECTRICAL CIRCUITS WITHOUT THE VENTILATION SYSTEM YOU WILL CAUSE DAMAGE TO ELECTRICAL EQUIPMENT.

Subtask 21-26-42-861-058-A

A. Energize the ground service network
(Ref. AMM TASK 24-42-00-861-001).

Subtask 21-26-42-865-059-A

B. Open, safety and tag this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	AIR COND/AVNCS VENT/CTL	6HQ	D06
49VU	AIR COND/AVNCS VENT/CTL	5HQ	D05
122VU	AIR COND/AVNCS/VENT/MONG	3HQ	Y17
** ON A/C NOT FOR ALL
123VU	AVNCS VENT/EXTC/FAN	2HQ	AE02
** ON A/C ALL
123VU	AVNCS VENT/BLOWER/FAN	1HQ	AD10
** ON A/C NOT FOR ALL
123VU	AVNCS VENT/EXTC/FAN	2HQ	AC04

Subtask 21-26-42-010-060-A

C. Get Access
(1) Put the ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position at the access door 824.
(2) Open the access door 824 (Ref. AMM TASK 52-41-00-010-002).
(3) Remove access panel 128EG (Ref. AMM TASK 53-12-13-000-001).

4. Procedure
Subtask 21-26-42-020-056-A

A. Removal of the Avionics Equipment Blowing-Duct

Avionics Equipment Blowing-Duct

(1) Remove the clamp (17) and disconnect the drain hose (16) from the duct (14).
(2) Remove the clamps (18) and (22).
(3) Hold the duct (14) and remove the clamp (15).
(4) Remove the duct (14) and discard the O-ring (21).
(5) Put the PLUG-BLANKING in each disconnected line end.

Subtask 21-26-42-020-057-A

B. Removal of the Avionics Equipment Extraction-Ducts

Avionics Equipment Extraction-Ducts

(1) Remove the clamps (6) and the sleeve (5).
(2) Remove the clamp (3).
(3) Remove the clamps (7) and the flexible sleeve (8).
(4) Remove the duct (4) and discard the O-ring (2).
(5) Remove the clamps (12) and the flexible sleeve (13).
(6) Remove the clamp (11).
(7) Remove the duct (9) and discard the O-ring (10).
(8) Put the PLUG-BLANKING in each disconnected line end.

[Rev.10 from 2021] 2026.04.02 06:11:04 UTC