Adjustment of the RAT Interlock Proximity Switch
TASK 29-22-00-820-005-A
Adjustment of the RAT Interlock Proximity Switch
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Work Zones and Access Panels
C. Referenced Information
3. Job Set-up
Subtask 29-22-00-860-115-A
Subtask 29-22-00-820-067-A
Subtask 29-22-00-860-116-A
[Rev.10 from 2021]
2026.04.01 00:26:02 UTC
Adjustment of the RAT Interlock Proximity Switch
WARNING:
PUT THE SAFETY DEVICES AND THE WARNING NOTICES IN POSITION BEFORE YOU START A TASK ON OR NEAR:
- THE FLIGHT CONTROLS
- THE FLIGHT CONTROL SURFACES
- THE LANDING GEAR AND THE RELATED DOORS
- COMPONENTS THAT MOVE.
WARNING:
MAKE SURE THAT THE TRAVEL RANGES OF THE FLIGHT CONTROLS SURFACES ARE CLEAR. MOVEMENT OF FLIGHT CONTROLS CAN CAUSE INJURY TO PERSONS AND/OR DAMAGE TO EQUIPMENT.
WARNING:
MAKE SURE THAT THE RAT TRAVEL RANGE IS CLEAR BEFORE YOU EXTEND/RETRACT THE RAT.
WARNING:
MAKE SURE THAT THE GROUND SAFETY-LOCKS ARE IN POSITION ON THE LANDING GEAR. THIS WILL PREVENT UNWANTED MOVEMENT OF THE LANDING GEAR, AND THUS POSSIBLE INJURY TO PERSONS AND DAMAGE TO THE AIRCRAFT AND/OR EQUIPMENT.
ZONE: 195
1. Reason for the JobSelf explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Work Zones and Access Panels
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| 195 | HYDRAULIC COMPT AND FAIRINGS |
| REFERENCE | DESIGNATION |
|---|---|
| TASK 24-41-00-861-002-A | Energize the Aircraft Electrical Circuits from the External Power |
| TASK 24-41-00-861-002-A-01 | Energize the Aircraft Electrical Circuits from the APU |
| TASK 24-41-00-861-002-A-02 | Energize the Aircraft Electrical Circuits from Engine 1(2) |
| TASK 24-41-00-862-002-A | De-energize the Aircraft Electrical Circuits Supplied from the External Power |
| TASK 24-41-00-862-002-A-01 | De-energize the Aircraft Electrical Circuits Supplied from the APU |
| TASK 24-41-00-862-002-A-02 | De-energize the Aircraft Electrical Circuits Supplied from the Engine 1(2) |
| TASK 29-00-00-864-001-A | Put the Related Hydraulic System in the Depressurized Configuration before Maintenance Action |
| TASK 29-14-00-614-001-A | Depressurization of the Hydraulic Reservoirs |
| TASK 29-22-00-710-007-A | Operational Test of the Manual Deployment and the Retraction of the Ram Air Turbine |
| TASK 29-22-00-869-005-A | Extension of the Ram Air Turbine (RAT) on the Ground |
| TASK 29-22-51-400-011-A | Installation of the RAT Interlock Proximity Switch |
Subtask 29-22-00-860-115-A
A. Aircraft Maintenance Configuration
(1) As necessary, use the applicable SAFETY BARRIERS, specified by the operator's instructions and your local regulations.
(2) Put the WARNING NOTICE(S) in position to tell persons not to pressurize the Blue hydraulic system:
(Ref. AMM TASK 29-00-00-864-001).
(4) Depressurize the reservoir of the Blue hydraulic system (Ref. AMM TASK 29-14-00-614-001).
(5) Extend the Ram Air Turbine (RAT) (Ref. AMM TASK 29-22-00-869-005).
(6) Install the COVER - PROTECTION on the turbine blades.
Subtask 29-22-00-865-117-A (1) As necessary, use the applicable SAFETY BARRIERS, specified by the operator's instructions and your local regulations.
(2) Put the WARNING NOTICE(S) in position to tell persons not to pressurize the Blue hydraulic system:
- In the cockpit on the hydraulic section 40VU of the overhead panel
- On the ground service panel of the Blue hydraulic system.
(Ref. AMM TASK 29-00-00-864-001).
(4) Depressurize the reservoir of the Blue hydraulic system (Ref. AMM TASK 29-14-00-614-001).
(5) Extend the Ram Air Turbine (RAT) (Ref. AMM TASK 29-22-00-869-005).
(6) Install the COVER - PROTECTION on the turbine blades.
B. Open, safety and tag this(these) circuit breaker(s):
4. Procedure| PANEL | DESIGNATION | FIN | LOCATION |
|---|---|---|---|
| ** ON A/C NOT FOR ALL | |||
| 49VU | HYD/RAT/CTL | 2801GE | D14 |
| ** ON A/C NOT FOR ALL | |||
| 49VU | HYD/RAT/CTL | 2801GE | B13 |
| ** ON A/C ALL | |||
| 106VU | CSM/G /EV/MAN/SPLY | 6XE | B04 |
| 121VU | HYDRAULIC/RAT/SPLY/EXTN/SOL1 | 2803GE | P33 |
Subtask 29-22-00-820-067-A
A. Adjustment of the RAT Interlock Proximity Switch
(1) Turn the blades of the RAT out of line with the leg assembly (4).
(2) Install an INCLINOMETER on the top of the RAT hub (at 12 O'clock position).
(3) Set the inclinometer to zero.
(4) Remove the nut (10), the washers (9), (5) and the bolt (6) which attaches the eye-end (8) of the RAT actuator to the leg assembly (4).
(5) Remove the the RAT actuator from the forked mounting (7).
(6) Move the leg assembly (4) from the horizontal position (0 degrees on the inclinometer) approximately 6 degrees to the stowed position. In this position measure the dimension "X" between the interlock proximity switch (3) and the flag lever (1). Make sure that the value is between 0.018 in. (0.4572 mm) and 0.020 in. (0.5080 mm). If necessary adjust the value of the dimension "X" with applicable shims (Ref. AMM TASK 29-22-51-400-011).
(8) Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):
2801GE.
(9) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
(10) On the RAT ground control-panel 3GE (11):
(12) Move the leg assembly (4) from the horizontal position (0 degrees on the inclinometer) to the stowed position.
(14) If necessary, adjust the RAT interlock proximity switch (3) as follows:
(a) If the INTERLOCK WARNING lamp comes on before the leg assembly (4) is in the 6 degree position:
.
(16) Set the stow switch on the RAT ground control panel 3GE (11) to the RESET position and release it to reset the interlock logic in the RAT ground control panel 3GE.
(17) Turn the blades of the RAT in line with the leg assembly (4).
(18) Move the leg assembly (4) from the horizontal position (0 degrees on the inclinometer) to the stowed position.
(19) Make sure that the INTERLOCK WARNING lamp on the RAT ground control panel 3GE (11) does not come on.
(20) On the RAT ground control-panel 3GE (11):
(Ref. AMM TASK 24-41-00-862-002).
(22) Open, safety and tag this(these) circuit breaker(s):
2801GE.
(23) Remove the inclinometer from the RAT hub.
(24) Put the eye-end (8) of the RAT actuator between the forked mounting (7).
(25) Loosely install the bolt (6), the washers (5) and (9) and the nut (10).
.
(27) Remove the COVER - PROTECTION from the turbine blades.
Subtask 29-22-00-710-069-A (1) Turn the blades of the RAT out of line with the leg assembly (4).
(2) Install an INCLINOMETER on the top of the RAT hub (at 12 O'clock position).
(3) Set the inclinometer to zero.
(4) Remove the nut (10), the washers (9), (5) and the bolt (6) which attaches the eye-end (8) of the RAT actuator to the leg assembly (4).
(5) Remove the the RAT actuator from the forked mounting (7).
(6) Move the leg assembly (4) from the horizontal position (0 degrees on the inclinometer) approximately 6 degrees to the stowed position. In this position measure the dimension "X" between the interlock proximity switch (3) and the flag lever (1). Make sure that the value is between 0.018 in. (0.4572 mm) and 0.020 in. (0.5080 mm). If necessary adjust the value of the dimension "X" with applicable shims (Ref. AMM TASK 29-22-51-400-011).
NOTE: Make sure that the RAT blades do not touch the fuselage.
(7) Release the leg assembly (4) to the horizontal position. (8) Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):
2801GE.
(9) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
(10) On the RAT ground control-panel 3GE (11):
- Set the 28VDC switch to the ON position
- Set the LAMP TEST switch to the test position and make sure that all lamps come on.
(12) Move the leg assembly (4) from the horizontal position (0 degrees on the inclinometer) to the stowed position.
NOTE: Make sure that the RAT blades do not touch the fuselage.
(13) Make sure that the INTERLOCK WARNING lamp on the RAT ground control panel 3GE (11) comes on between 6 and 7 degrees from the horizontal position. (14) If necessary, adjust the RAT interlock proximity switch (3) as follows:
(a) If the INTERLOCK WARNING lamp comes on before the leg assembly (4) is in the 6 degree position:
- Loosen the nuts (2) and move the RAT interlock proximity switch (3) in the forward direction.
- Loosen the nuts (2) and move the RAT interlock proximity switch (3) in the rearward direction.
. (16) Set the stow switch on the RAT ground control panel 3GE (11) to the RESET position and release it to reset the interlock logic in the RAT ground control panel 3GE.
(17) Turn the blades of the RAT in line with the leg assembly (4).
(18) Move the leg assembly (4) from the horizontal position (0 degrees on the inclinometer) to the stowed position.
(19) Make sure that the INTERLOCK WARNING lamp on the RAT ground control panel 3GE (11) does not come on.
(20) On the RAT ground control-panel 3GE (11):
- Set the 28VDC switch to the OFF position.
(Ref. AMM TASK 24-41-00-862-002).
(22) Open, safety and tag this(these) circuit breaker(s):
2801GE.
(23) Remove the inclinometer from the RAT hub.
(24) Put the eye-end (8) of the RAT actuator between the forked mounting (7).
(25) Loosely install the bolt (6), the washers (5) and (9) and the nut (10).
NOTE: Because of the design, there is a clearance between the washers (5), (9) and the leg assembly (4).
(26) TORQUE the nut (10) to between 5.29 and 4.74 m.daN (39.01 and 34.96 lbf.ft )
. (27) Remove the COVER - PROTECTION from the turbine blades.
B. Do an operational test of the manual deployment and the retraction of the RAT (Ref. AMM TASK 29-22-00-710-007).
5. Close-upSubtask 29-22-00-860-116-A
A. Put the aircraft back to the serviceable condition.
(1) Remove the access platform(s).
(2) Remove the safety barriers.
(3) Remove the WARNING NOTICE(S).
(1) Remove the access platform(s).
(2) Remove the safety barriers.
(3) Remove the WARNING NOTICE(S).
RAT Interlock Proximity Switch