W DOC AIRBUS | AMM A320F

Analyze Hydraulic Fluid

TASK 12-32-29-281-001-A
Analyze Hydraulic Fluid

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.
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 CONTROLS AGREE WITH THE POSITION OF THE ITEMS THEY OPERATE BEFORE YOU PRESSURIZE A HYDRAULIC SYSTEM. UNWANTED MOVEMENT OF HYDRAULICALLY OPERATED ITEMS CAN CAUSE SERIOUS INJURY AND/OR DAMAGE.
WARNING: OBEY THE HYDRAULIC SAFETY PROCEDURES.
WARNING: DO NOT GET THE FLUID ON YOUR SKIN OR IN YOUR EYES. IF YOU DO:
  • FLUSH IT AWAY WITH CLEAN WATER
  • GET MEDICAL AID.
WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
ZONE: 147
ZONE: 195
ZONE: 196
FIN: 1187GM
FIN: 2187GM
FIN: 3187GM
1. Reason for the Job
Refer to the MPD TASK: 291000-15
ANALYZE HYDRAULIC FLUID
2. Job Set-up Information
 A. Fixtures, Tools, Test and Support Equipment
REFERENCE
QTY
DESIGNATION
No specific
3
BOTTLE - SAMPLE
No specific
1
CONTAINER - CLEAN, APPLICABLE
No specific
1
WARNING NOTICE(S)
 B. Consumable Materials
REFERENCE
DESIGNATION
(Material No.08BBB1)
Non Aqueous Cleaner-- Petroleum Based -
(Material No.08BBF1)
Non Aqueous Cleaner_- Methyl-Ethyl-Ketone -
(Material No.14QFB1)
Wire-Locking Dia: 0.8 mm CRES Nickel Alloy -
(Material No.14SBA1)
Textile-Lint free Cotton -
 C. Work Zones and Access Panels
ZONE/ACCESS
ZONE DESCRIPTION
147
MAIN GEAR WELL AND HYDRAULIC COMPARTMENT
195
HYDRAULIC COMPT AND FAIRINGS
196
HYDRAULIC COMPT AND FAIRINGS
195BB, 196BB
 D. Referenced Information
REFERENCE
DESIGNATION
TASK 12-12-29-611-001-A
Fill the Hydraulic Fluid Reservoir with a Hand Pump
TASK 12-32-29-281-001-A
Analyze Hydraulic Fluid
TASK 12-32-29-281-802-A
Sampling for Analysis (One System Contaminated in Particle)
TASK 12-32-29-281-803-A
Measure the Fluid Particle Content of Green, Blue and Yellow Systems with Laser Particle Analyser
TASK 12-36-29-600-001-A
Change of the Hydraulic Fluid in the Green Hydraulic System - with Ground Cart Available
TASK 12-36-29-600-002-A
Change of the Hydraulic Fluid in the Yellow Hydraulic System - with Ground Cart Available
TASK 12-36-29-600-003-A
Change of the Hydraulic Fluid in the Blue Hydraulic System - with Ground Cart Available
TASK 12-36-29-600-004-A
Reclamation of the Hydraulic Fluid in the Green Hydraulic System
TASK 12-36-29-600-005-A
Reclamation of the Hydraulic Fluid in the Yellow Hydraulic System
TASK 12-36-29-600-006-A
Reclamation of the Hydraulic Fluid in the Blue Hydraulic System
TASK 12-36-29-600-802-A
Replacement of the Hydraulic Fluid in the Green Hydraulic System because of an Increased Level of Acidity when a Ground Cart is not Available
TASK 12-36-29-600-803-A
Replacement of the Hydraulic Fluid in the Blue Hydraulic System because of an Increased Level of Acidity when a Ground Cart is not Available
TASK 12-36-29-600-804-A
Replacement of the Hydraulic Fluid in the Yellow Hydraulic System because of an Increased Level of Acidity when a Ground Cart is not Available
TASK 12-36-29-615-001-A
Clean the Fluid in the Green Hydraulic System
TASK 12-36-29-615-002-A
Clean the Fluid in the Yellow Hydraulic System
TASK 12-36-29-615-003-A
Clean the Fluid in the Blue Hydraulic System
TASK 12-36-29-615-802-A
Cleaning of the Hydraulic Fluid in the Green Hydraulic System with the Water Separation System (WSS4)
TASK 12-36-29-615-803-A
Cleaning of the Hydraulic Fluid in the Yellow Hydraulic System with the Water Separation System (WSS4)
TASK 12-36-29-615-804-A
Cleaning of the Hydraulic Fluid in the Blue Hydraulic System with the Water Separation System (WSS4)
TASK 20-11-11-911-001-A
Safetying with Lockwire
TASK 20-23-21-911-001-A
Removal/Installation of the Bobbins from their Housings and Installation of O-rings, Square Seals, and Back-up Rings on the Bobbins
TASK 27-14-00-710-001-A
Operational Test of the Aileron and Hydraulic Actuation
TASK 27-24-00-710-001-A
Operational Test of the Rudder Hydraulic Actuation
TASK 27-24-00-710-002-A
Operational Test of the Rudder Servocontrols with Individual Hydraulic System
TASK 27-26-00-710-001-A
Operational Test of the Yaw Damper Actuation
TASK 27-34-00-710-001-A
Operational Test of the Elevator and Hydraulic Actuation
TASK 27-44-00-710-001-A
Operational Test of the Jamming Protection Device of the Trimmable Horizontal Stabilizer Actuator
TASK 27-44-00-710-002-A
Operational Test of the Trimmable Horizontal Stabilizer Actuator with the Individual Hydraulic Systems
TASK 27-44-54-720-001-A
Functional Test of the Pressure-Off Brakes
TASK 27-51-00-710-001-A
Operational Test of the Wing Tip Brake and the Pressure Off Brake
TASK 27-54-00-710-001-A
Operational Test of the Flap System
TASK 27-64-00-710-001-A
Operational Test of the Spoiler Hydraulic Actuation
TASK 27-81-00-710-001-A
Operational Test of the Wing-Tip Brake and the Pressure-Off Brake
TASK 27-84-00-710-001-A
Operational Test of the Slat System
TASK 27-96-00-710-007-A
Operational Check of the Damping Measurement by BITE (Aileron)
TASK 27-96-00-710-008-A
Operational Check of the Damping Measurement by BITE (Elevator)
TASK 29-00-00-280-001-A
Check of the Internal Leakage of the Green Hydraulic System
TASK 29-00-00-280-002-A
Check of the Internal Leakage of the Blue Hydraulic System
TASK 29-00-00-280-003-A
Check of the Internal Leakage of the Yellow Hydraulic System
TASK 29-00-00-910-002-A
Safety Procedures of the Hydraulic System
TASK 29-10-00-863-001-A
Pressurize the Green Hydraulic System with a Hydraulic Ground Power-Cart
TASK 29-10-00-863-002-A
Pressurize the Yellow Hydraulic System with a Hydraulic Ground Power-Cart
TASK 29-10-00-863-003-A
Pressurize the Blue Hydraulic System with a Hydraulic Ground Power-Cart
TASK 29-10-00-863-003-A-01
Pressurize the Blue Hydraulic System with the Blue Electric Pump
TASK 29-10-00-864-001-A
Depressurize the Green Hydraulic System
TASK 29-10-00-864-002-A
Depressurize the Yellow Hydraulic System
TASK 29-10-00-864-003-A
Depressurize the Blue Hydraulic System
TASK 29-11-14-400-001-A
Installation of the HP Manifold of the Green Hydraulic System
TASK 29-11-43-610-010-A
Servicing of the Engine-Pump Case-Drain Filter
TASK 29-11-43-610-041-A
Servicing the Engine-Pump Case-Drain Filter
TASK 29-11-43-610-802-A
Servicing of the Engine-Pump Case-Drain Filter
TASK 29-11-44-610-001-A
Servicing of the LP-Filter
TASK 29-11-45-610-001-A
Servicing of the HP-Filter
TASK 29-12-14-400-001-A
Installation of the HP Manifold of the Blue Hydraulic System
TASK 29-12-43-610-001-A
Servicing of the Electric-Pump Case-Drain Filter
TASK 29-12-44-610-001-A
Servicing of the LP-Filter
TASK 29-12-45-610-001-A
Servicing of the HP-Filter
TASK 29-13-14-400-001-A
Installation of the HP Manifold of the Yellow Hydraulic System
TASK 29-13-43-610-010-A
Servicing of the Engine-Pump Case-Drain Filter
TASK 29-13-43-610-041-A
Servicing of the Engine Pump Case-Drain Filter
TASK 29-13-43-610-802-A
Servicing of the Engine-Pump Case-Drain Filter
TASK 29-13-44-610-001-A
Servicing of the LP-Filter
TASK 29-13-45-610-001-A
Servicing of the HP-Filter
TASK 29-22-00-720-003-A
Operational Check of RAT Manual Deployment and Functional Check of RAT using Ground Test Unit, followed by Check of Filter Indicator
TASK 29-23-00-863-001-A
Pressurize the Green Hydraulic System from the Yellow Hydraulic System through the PTU with the Electric Pump
TASK 32-12-00-010-001-A
Open the Main Gear Doors for Access
TASK 32-12-00-410-001-A
Close the Main Gear Doors after Access
F Sampling Valves - Location and Operation
F Fluid Analysis - Chemical Content
F Fluid Analysis - Particles content - Flow Chart 1
F Fluid Analysis - Particles content - Flow Chart 2
3. Job Set-up
Subtask 12-32-29-941-050-A
A. Safety Precautions
   (1) Obey the hydraulic safety procedures (Ref. AMM TASK 29-00-00-910-002).
   (2) Put the WARNING NOTICE(S) in position to tell persons not to move:
  • The flight controls
  • The lever of the landing gear selector.
Subtask 12-32-29-863-050-A
B. Pressurize the hydraulic system(s)
   (1) Pressurize the applicable hydraulic system:
Subtask 12-32-29-010-050-A
C. Get Access
   (1) Open the applicable access panel/door:
  • For the Green hydraulic system, open the left MLG door (Ref. AMM TASK 32-12-00-010-001).
  • For the Yellow hydraulic system, open access panel 196BB.
  • For the Blue hydraulic system, open access panel 195BB.
Subtask 12-32-29-866-050-A
D. If you operated the hydraulic systems more than one hour ago
Subtask 12-32-29-710-050-A
E. Tests
NOTE: If you get a sample from more than 1 Hydraulic System, it is necessary to do the tests below only one time.
NOTE: The following tests are not necessary but if they are not done, please be informed that 2 days or 36 flight hours (whichever occurs first) to go back to the main base will not be permitted in case of particle contamination on 1 Hydraulic System.
   (1) Do the Operational Test for the Green Hydraulic System:
     (a) Do the operational test of the Ailerons:
     (b) Do the operational test of the Rudder Servocontrols with Individual Hydraulic System (Ref. AMM TASK 27-24-00-710-002).
     (c) Do the operational test of the Yaw Damper Actuation (Ref. AMM TASK 27-26-00-710-001).
     (d) Do the operational test of the Elevators:
     (e) Do the operational test of the Spoiler Hydraulic Actuation (Ref. AMM TASK 27-64-00-710-001).
     (f) Do the operational test of the Trimmable Horizontal Stabilizer (THS):
     (g) Do the operational test of the Flap System:
     (h) Do the operational test of the Slat System:
   (2) Do the Operational Test for the Blue Hydraulic System:
     (a) Do the operational test of the Ailerons:
     (b) Do the operational test of the Rudder Servocontrols with Individual Hydraulic System (Ref. AMM TASK 27-24-00-710-002).
     (c) Do the operational test of the Yaw Damper Actuation (Ref. AMM TASK 27-26-00-710-001).
     (d) Do the operational test of the Elevators:
     (e) Do the operational test of the Spoiler Hydraulic Actuation (Ref. AMM TASK 27-64-00-710-001).
     (f) Do the operational test of the Flap System:
     (g) Do the operational test of the Slat System:
   (3) Do the Operational Test for the Yellow Hydraulic System:
     (a) Do the operational test of the Ailerons:
     (b) Do the operational test of the Rudder Servocontrols with Individual Hydraulic System (Ref. AMM TASK 27-24-00-710-002).
     (c) Do the operational test of the Yaw Damper Actuation (Ref. AMM TASK 27-26-00-710-001).
     (d) Do the operational test of the Elevators:
     (e) Do the operational test of the Spoiler Hydraulic Actuation (Ref. AMM TASK 27-64-00-710-001).
     (f) Do the operational test of the Trimmable Horizontal Stabilizer (THS):
     (g) Do the operational test of the Flap System:
4. Procedure
Subtask 12-32-29-281-050-A
A. Remove a Sample from the Sampling Valve
   (1) Flush the Sampling Valve:
WARNING: USE PROTECTIVE GOGGLES AND GLOVES WHEN YOU REMOVE OR INSTALL LOCKWIRE. EACH TIME YOU CUT LOCKWIRE, REMOVE AND DISCARD IT IMMEDIATELY. LOOSE LOCKWIRE CAN CUT YOU OR MAKE YOU BLIND, AND/OR CAN CAUSE DAMAGE.
     (a) Remove and discard the lockwire from the applicable sampling valve:
       1 For the Green hydraulic system, sampling valve 1187GM
       2 For the Yellow hydraulic system, sampling valve 3187GM
       3 For the Blue hydraulic system, sampling valve 2187GM.
     (b) Remove the cap from the sampling valve.
     (c) Carefully clean the hydraulic sampling valve with the petroleum ether with Non Aqueous Cleaner_- Methyl-Ethyl-Ketone - (Material No.08BBF1) (or as alternative cleaner use Non Aqueous Cleaner-- Petroleum Based - (Material No.08BBB1) ), Textile-Lint free Cotton - (Material No.14SBA1) .
     (d) Put the CONTAINER - CLEAN, APPLICABLE below the sampling valve.
     (e) Put the notch in the head of the cap below the head of the needle valve.
     (f) Move the cap to pull the needle valve down and drain 0.2 l (0.0528 USgal) into the applicable container.
     (g) Remove the cap from the needle valve.
     (h) Discard the hydraulic fluid (refer to the local regulations).
   (2) Put the clean glass BOTTLE - SAMPLE or the plastic (non PVC) BOTTLE - SAMPLE below the sampling valve. Do not use a container/bottle made from polyvinyl chloride (PVC). This material will affect the results from the hydraulic fluid sample.
   (3) Put the notch in the head of the cap below the head of the needle valve.
F Sampling Valves - Location and Operation
   (4) Move the cap to pull the needle valve down and drain 0.2 l (0.0528 USgal) into the sample bottle.
   (5) Remove the cap from the needle valve.
   (6) Install the cap on the sampling valve.
WARNING: USE PROTECTIVE GOGGLES AND GLOVES WHEN YOU REMOVE OR INSTALL LOCKWIRE. EACH TIME YOU CUT LOCKWIRE, REMOVE AND DISCARD IT IMMEDIATELY. LOOSE LOCKWIRE CAN CUT YOU OR MAKE YOU BLIND, AND/OR CAN CAUSE DAMAGE.
   (7) Safety the cap with 14QFB1Wire-Locking Dia: 0.8 mm CRES Nickel Alloy - (Ref. AMM TASK 20-11-11-911-001).
   (8) Seal the sample bottle.
   (9) Put a tag on the sample bottle with:
  • The aircraft registration
  • The system identification
  • The date and the time.
   (10) Send the sample bottle to the analysis laboratory.
NOTE: You can temporarily release the aircraft to service for a maximum of 30 days waiting for analysis results.
Subtask 12-32-29-281-052-A
B. Contamination Analysis with Particle Count x
   (1) Reference list of maximum limits of classes 8 and 9 of NSA 307110 specification:
     (a) NUMBER OF PARTICLES:
Particle size (1)
Particle size (2)
Class 8
Class 9
5 to 15 micron
6 to 14 micron
64000
128000
15 to 25 micron
14 to 21 micron
11400
22800
25 to 50 micron
21 to 38 micron
2025
4050
50 to 100 micron
38 to 70 micron
360
720
> 100 micron
> 70 micron
64
128
NOTE: (1) Size range, microscope particle counts, for the longest dimension as measured from AS598 or ISO 4407.
NOTE: (2) Size range, APC calibrated from ISO 11171 or an optical or electron microscope with image analysis software, for the projected area equivalent diameter.
NOTE: The values from (1) and (2) are differentially counted.
   (2) You can do the particle count with the Laser Particle Analyzer (LPA2) as an alternative to the procedure written below (Ref. AMM TASK 12-32-29-281-803).
NOTE: When you use the LPA2 to measure the number of particles, refer to the maximum limits of class 8.
   (3) Do the procedures that follow:
     (a) If a sample analysis has a contamination in the maximum limits given above, no more maintenance steps are necessary.
     (b) If the contamination value in the fluid sample is more than the values given in the table above (class 9):
       1 If there is ONLY ONE system contaminated, do (Ref. AMM TASK 12-32-29-281-802).
NOTE: If necessary, and if all the flight-controls operational tests given in Para. 3.E. are completed, you can:
  • Temporarily release the aircraft to service for a maximum of two days or 36 flight hours (that occurs first) to go back to the main base for maintenance.
       2 If there are MORE than ONE systems contaminated, do ONLY ONE of the procedures that follow, FLUID CHANGE OR FLUID CLEANING OR FLUID RECLAIM:
       3 FLUID CHANGE:
         a Replace all the filters (HP, LP & Case Drain) in the contaminated hydraulic systems:
         b Change the hydraulic fluid of all contaminated hydraulic systems:
         c Collect fluid sample on all contaminated hydraulic systems between 1 and 5 Flights Cycles (FC) after fluid change (Ref. AMM TASK 12-32-29-281-001).
NOTE: If necessary, you can temporarily release the A/C to service for a maximum of 14 days (starting at 1st flight after corrective action) waiting for the new sampling results.
NOTE: The sampling analysis can be done with the Laser Particle Analyzer (LPA2) tool.
NOTE: In this condition, it is not necessary to collect fluid samples between 1 and 5 FC and to wait for sampling results, as the LPA2 tool gives result immediately.

Or

       4 FLUID CLEANING:
         a Replace all the filters (HP, LP & Case Drain) in the contaminated hydraulic systems:
         b Clean the hydraulic fluid of all contaminated hydraulic systems with the HSPA181-380J HYDRAULIC PURIFIER or the WSS4 WATER SEPARATION SYSTEM:
         c Collect fluid sample between 1 and 5 FC after cleaning (Ref. AMM TASK 12-32-29-281-001).
NOTE: If necessary, you can temporarily release the A/C to service for a maximum of 14 days (starting at 1st flight after corrective action) waiting for the new sampling results.
NOTE: The sampling analysis can be done with the LPA2 tool.
NOTE: In this condition, it is not necessary to collect fluid samples between 1 and 5 FC and to wait for sampling results, as the LPA2 tool gives result immediately.

Or

       5 FLUID RECLAIM:
         a Repair the contaminated hydraulic systems:
         b Collect the sample immediately after the reclaim procedure (Ref. AMM TASK 12-32-29-281-001).
NOTE: Wait for approved sampling result before Aircraft DISPATCH.
NOTE: The reclaim procedure is shorter and less expensive than the fluid change procedure. But it is necessary to collect a fluid sample and wait for approved results before aircraft can be released into service.
NOTE: The sampling analysis can be done with the LPA2 tool.
     (c) If the contamination is confirmed, do necessary maintenance steps. New fluid sample analysis before aircraft release into service is necessary. Contact Airbus for more data if necessary.
Subtask 12-32-29-281-053-A
C. Chemical Analysis
Chemical analysis must be to NSA307110 "Limit Characteristics of fluid in operation". If the values of the chemical analysis are in the given limits, no further actions are required. The values below are the permitted limits for in-service fluid:
  • Acid number: 1.0 mg KOH/g maximum
  • Density at 23 +/- 3 deg.C: 970 to 1066 kg/m3 (60.56 to 66.55 lb/ft3)
  • Water content: 0.50% recommended, 0.80% maximum.
NOTE: The maximum water content is 0.80%. But to increase the hydraulic fluid life, Airbus recommends to keep this value at less than 0.50%.
  • Viscosity at 38 deg.C: 6.0 to 12.5 CST
  • Chlorine content: 200 ppm maximum
  • Electrical conductivity: 0.30 microSiemens.cm-1 minimum.
   (1) Additional Temporary Authorizations:
     (a) The table that follows gives you the approval for aircraft dispatch if the result of the fluid chemical analysis is not in the correct limits.
Hydraulic Fluid Parameters
In Service Limits
Corrective Action Application
Tolerance (see NOTE 1)
Permitted Time Frames (see NOTE 2)
Acid number
1.0 mg KOH/g maximum
immediately
1.0 to 3.5mg KOH/g
see the table Para. 4.D.(4)
Density
970 to 1066 kg/m3
immediately
not applicable
less than
600FH or 750FC
which come first
Water content
0.5% recommended
0.8% maximum
immediately
0.8% to 1.0%
less than 600 FH or 750 FC which comes first
Water content
0.5% recommended
0.8% maximum
immediately
1.0% to 1.5%
7 calendar days
Viscosity
6.0 to 12.5 CST
immediately
at 38 deg.C:
5.5 to 6.0 CST
10 calendar days
or 150 FH
Chlorine content
200 ppm maximum
immediately
200 to 300 ppm
10 calendar days
or 150 FH
Electrical
conductivity
0.30 microSimens.cm-1 minimum
immediately
lower than
0.30 microSiemens.cm-1
less than
600FH or 750FC
which come first
NOTE: 1: Tolerance shows the level of contaminations allowed for a limited time duration (see associated allowed time frame).
NOTE: 2: Permitted Time Frame is an additional time the aircraft can stay in service. It is the period from the discovery of the contamination to selected corrective action.
Subtask 12-32-29-281-058-A
D. Repercussion of the Chemical Analysis
   (1) Water contamination:
     (a) If the water contamination is from 0.8% to 1.3%:
       1 Clean the hydraulic fluid of the applicable hydraulic system with the HSPA181-380J HYDRAULIC PURIFIER or the WSS4 WATER SEPARATION SYSTEM:

or

Change the hydraulic fluid of the applicable hydraulic system
(Ref. AMM TASK 12-36-29-600-001)
(Ref. AMM TASK 12-36-29-600-002)
(Ref. AMM TASK 12-36-29-600-003).

       2 Collect a new hydraulic fluid sample between 1 to 5 FC after corrective action.
NOTE: If necessary, you can temporarily release the A/C to service for a maximum of 14 days (starting at 1st flight after corrective action) waiting for the new sampling results.
       3 Remove the LP/HP filter elements of the applicable hydraulic system as given in the subsequent procedures:
         a For the Green hydraulic system
(Ref. AMM TASK 29-11-44-610-001)
(Ref. AMM TASK 29-11-45-610-001)
         b For the Blue hydraulic system
(Ref. AMM TASK 29-12-44-610-001)
(Ref. AMM TASK 29-12-45-610-001)
         c For the Yellow hydraulic system
(Ref. AMM TASK 29-13-44-610-001)
(Ref. AMM TASK 29-13-45-610-001).
       4 Examine the applicable filter elements for corroded particles.
       5 If you find no corroded particles:
         a Make sure that the filter elements are clean and in the correct condition. If necessary, replace the applicable filter element with a new one.
         b Install the LP/HP filter elements as given in the subsequent procedures:
       6 If you find corroded particles:
         a Install new HP/LP filter elements as given in the subsequent procedures:
         b Continue with the procedures given in step (1)(b)(2_) and subsequent and step (1)(c)(2_) and subsequent.

     (b) If the water contamination is more than 1.3% and less than 2.5%:
       1 Do the procedure given under step (1)(a) and also:
       2 Do the check of the internal leakage of the applicable hydraulic system
(Ref. AMM TASK 29-00-00-280-001)
(Ref. AMM TASK 29-00-00-280-002)
(Ref. AMM TASK 29-00-00-280-003).
       3 Do the operational test of the wing tip brake and the pressure off brake
(Ref. AMM TASK 27-51-00-710-001)
(Ref. AMM TASK 27-81-00-710-001).
       4 Remove the bobbins of the HP manifold of the applicable hydraulic system
(Ref. AMM TASK 29-11-14-400-001)
(Ref. AMM TASK 29-12-14-400-001)
(Ref. AMM TASK 29-13-14-400-001)
(Ref. AMM TASK 20-23-21-911-001).
       5 Examine the bobbins for signs of corrosion.
         a If you find no signs of corrosion:
  • Install the bobbins
         b If you find signs of corrosion:
  • Replace the bobbins and the applicable component.
       6 If you found corroded particles or signs of corrosion:
         a Continue with the procedures given in step (1)(c)(2_) to (1)(c)(5_).

     (c) If the water contamination is more than 2.5%:
       1 Do the procedures given in step (1)(a) and step (1)(b)(2_) to (1)(b)(6_).
       2 Do the functional test of the ram air turbine
(Ref. AMM TASK 29-22-00-720-003).
       3 Do the operational test of the damping measurement of the aileron
(Ref. AMM TASK 27-96-00-710-007).
       4 Do the operational test of the damping measurement of the elevator
(Ref. AMM TASK 27-96-00-710-008).
       5 Do the operational test of the rudder hydraulic actuation
(Ref. AMM TASK 27-24-00-710-001).
   (2) Chlorine contamination:
     (a) If the chlorine content of the fluid sample is equal to or more than the values given above:
       1 Clean the hydraulic fluid of the applicable hydraulic system with the HSPA181-380J HYDRAULIC PURIFIER or the WSS4 WATER SEPARATION SYSTEM:

or

Change the hydraulic fluid of the applicable hydraulic system (Ref. AMM TASK 12-36-29-600-001), (Ref. AMM TASK 12-36-29-600-002) and (Ref. AMM TASK 12-36-29-600-003).
       2 Collect a new hydraulic fluid sample between 1 to 5 FC after corrective action.
NOTE: If necessary, you can temporarily release the A/C to service for a maximum of 14 days (starting at 1st flight after corrective action) waiting for the new sampling results.
   (3) Density, Viscosity or Conductivity contamination:
     (a) If the density, viscosity or conductivity of the fluid sample is not in the permitted limits given above:
       1 Change the hydraulic fluid of the applicable hydraulic system (Ref. AMM TASK 12-36-29-600-001), (Ref. AMM TASK 12-36-29-600-002) and (Ref. AMM TASK 12-36-29-600-003).
       2 Collect a new hydraulic fluid sample between 1 to 5 FC after corrective action.
NOTE: If necessary, you can temporarily release the A/C to service for a maximum of 14 days (starting at 1st flight after corrective action) waiting for the new sampling results.
   (4) Acidity contamination:
Acidity Level
Grace Period for Corrective Action
Fluid Replacement
Procedure
Acidity <= 1.0
not applicable
not applicable
next MPD check
1.0 < acidity <= 1.2
30 days
2x reservoir fluid replacement (see NOTE 1)
1. Replace fluid in grace period and operate flight controls between each reservoir refilling or do minimum 1 FC.
2. Take a new sample minimum after 1 FC and in 1 week (see NOTE 2). Test result must be available in 30 days.
3. If acidity level is less than 1, do a check of acidity level at next MPD check.
1.2 < acidity <= 1.5
3x reservoir fluid replacement (see NOTE 1)
1.5 < acidity <= 1.8
14 days
4x reservoir fluid replacement (see NOTE 1)
1.8 < acidity <= 2.2
5x reservoir fluid replacement (see NOTE 1)
2.2 < acidity <= 2.5
6x reservoir fluid replacement (see NOTE 1)
2.5 < acidity <= 3.5
3 FC if only one system is affected and there is no contamination in other systems.
NOTE: If there is a contamination in more than one system, no grace period is allowed.
Change the hydraulic fluid of the applicable hydraulic system (Ref. AMM TASK 12-36-29-600-001), (Ref. AMM TASK 12-36-29-600-002) and (Ref. AMM TASK 12-36-29-600-003).
1. Replace fluid in grace period.
2. Take a new sample minimum after 1 FC and in one week (see NOTE 2). Test result must be available in 30 days.
3. If acidity level is less than 1, do a check of acidity level at next MPD check.
Acidity > 3.5
no grace period
NOTE: 1: For the replacement of the hydraulic fluid of the applicable hydraulic system in the reservoir only, refer to (Ref. AMM TASK 12-36-29-600-802), (Ref. AMM TASK 12-36-29-600-803) and (Ref. AMM TASK 12-36-29-600-804). This procedure will help you to avoid hydraulic fluid replacement in all of the hydraulic system.
You can also change the hydraulic fluid of the related hydraulic system (Ref. AMM TASK 12-36-29-600-001), (Ref. AMM TASK 12-36-29-600-002) and (Ref. AMM TASK 12-36-29-600-003).
NOTE: 2: For parking and storage, the FC can be replaced with 5 minutes flight control operation. Refer to Para. 3.E.
Subtask 12-32-29-860-050-A
E. Put the aircraft back to the serviceable condition.
   (1) Depressurize the hydraulic system:
5. Close-up
Subtask 12-32-29-611-050-A
A. Make sure that the fluid level in the hydraulic reservoirs is correct. If necessary, fill the reservoirs (Ref. AMM TASK 12-12-29-611-001).
Subtask 12-32-29-410-050-A
B. Close Access
   (1) Make sure that the work area is clean and clear of tools and other items.
   (2) Close the applicable access panel/door:
  • For the Green hydraulic system, close the left MLG door (Ref. AMM TASK 32-12-00-410-001).
  • For the Yellow hydraulic system, close access door 196BB.
  • For the Blue hydraulic system, close access door 195BB.
   (3) Remove the WARNING NOTICE(S).
[Rev.10 from 2021] 2026.03.31 22:58:03 UTC
"Aviabrain" 2025