Installation of the Emergency Ram Air Inlet Actuator

TASK 21-55-51-400-001-A
Installation of the Emergency Ram Air Inlet Actuator

FIN: 7HZ

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	ACCESS PLATFORM 1M (3 FT)-ADJUSTABLE

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
191AB

C. Expendable Parts

FIG.ITEM	DESIGNATION	IPC-CSN
1	COTTER PINS	AIPC 21-55-02-01-090
1	COTTER PINS	AIPC 21-55-82-01-100

D. Referenced Information

REFERENCE	DESIGNATION
TASK 21-55-00-710-001-A	Operational Check of the Emergency Ram-Air Inlet System
TASK 24-42-00-861-001-A	Energize the Ground Service Network from the External Power
TASK 24-42-00-862-001-A	De-energize the Ground Service Network Supplied from the External Power
Emergency Ram Air Inlet Actuator

3. Job Set-up
Subtask 21-55-51-860-050-A

A. Aircraft Maintenance Configuration
(1) Make sure that the ground service network is energized
(Ref. AMM TASK 24-42-00-861-001).

Subtask 21-55-51-865-051-A

B. Make sure that this(these) circuit breaker(s) is(are) open, safetied and tagged:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	AIR COND/RAM/AIR/INLET	1HZ	D10

Subtask 21-55-51-010-051-A

C. Get Access
(1) Make sure that the ACCESS PLATFORM 1M (3 FT)-ADJUSTABLE is in position at the access panel 191AB.
(2) Make sure that the access panel 191AB is removed.

4. Procedure
Subtask 21-55-51-420-050-A

A. Installation of the Actuator
(1) Clean the component interfaces and the adjacent area.
(2) Do an inspection of the component interfaces and the adjacent area.
(3) Make sure that the length of the actuator (15) between the pivot point centers is 372.0 +1.0 mm or -1.0 mm (14.6457 +0.0394 in. or -0.0394 in.).
(4) Install the washers (7) and the bushings (6) and put the actuator (15) in position.
(5) Install the washer (4) and the bolt (5).
(6) Install the washer (3).
(7) Install the nut (2) and tighten it.
(8) Install the bolt (14).
(9) Install the washer (12).
(10) Install the nut (13) and tighten it.
(11) Lock the nuts (2) and (13) with the new AIPC 21-55-02-01-090 COTTER PINS (1) or AIPC 21-55-82-01-100 COTTER PINS (1).
(12) Remove the CAP-BLANKING from each electrical connector and receptacle.
(13) Make sure that all the electrical connections are clean and in the correct condition.
(14) Connect the electrical connector (16).
(15) Connect the bonding strip (9).
(a) Install the washer (10) and the screw (11).
(b) Install the nut (8) and tighten it.

Subtask 21-55-51-865-052-A

B. Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	AIR COND/RAM/AIR/INLET	1HZ	D10

Subtask 21-55-51-710-050-A

C. Do an operational test of the emergency ram air inlet (Ref. AMM TASK 21-55-00-710-001).

5. Close-up
Subtask 21-55-51-410-050-A

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Install the access panel 191AB.
(3) Remove the access platform(s).

Subtask 21-55-51-862-050-A

B. De-energize the ground service network
(Ref. AMM TASK 24-42-00-862-001).

[Rev.10 from 2021] 2026.04.02 06:11:33 UTC