Era Aw139 - Hydraulic System

Front 1

What are the 2 Circuits that make up the Hydraulic System on the AW139?

Back 1

2 Hydraulic Circuits
1. The Flight Control Circuit - (Main Rotor Tail Rotor)
2. The Utility Circuit - (Landing Gear Extension/Retraction)

Front 2

How many Hydraulic Sytems are there on the AW139?

Back 2

2 Hydraulic Systems on the AW139

Front 3

Which Hydraulic System supplies pressure to the FLight Controls?

Back 3

Both Systems

Front 4

What Hydraulic System is utilized to control the Landing gear in Emergency Situations only on the AW139?

Back 4

The #1 System is utilized to operate the landing gear in emergency situations for extension only.

Front 5

What hydraulic system normally operates the landing gear on the AW139?

Back 5

# 2 System operates the landing gear under normal conditions.

Front 6

What is the purpose of the TRSOV in the AW139 Hydraulic System?

What System is it part of and where is it located?

Back 6

TRSOV - Tail Rotor Shut Off Valve. Used to prevent or attempt to prevent further leakage in the Hydraulic System if the PCM levels are dropping.

TRSOV is located in the #2 System Aft of the #2 PCM

Front 7

What is the purpose of the Electrical Hydraulic Pump in the AW139?

What System is it part of?

Where is it located?

Back 7

Electrical Hydraulic Pump - Used to operate Flight Controls during Preflight Checks at a reduced pressure of 100Bar

It is part of #1 System

Located - FWD of the #1 PCM

Front 8

What indications are present on the Hydraulic Control Panel?

What control is present on the Hydraulic Control Panel?

Back 8

Control Panel Indications - Over Pressure & Over Temperature

Control Panel Functions - SOV shutoff control only.

Front 9

What is the purpose of the PCM's in the AW139 Hydraulic System?

Back 9

PCM's Store, Distribute and Monitor the Hydraulic Fluid for their respective systems.

Front 10

How many pumps are there total in the AW 139 Hydraulic system?

Back 10

3 Mechanical - Pump 1, 2, 4,
1 Electrical - Pump 3

Front 11

What Hydraulic Pumps and of which type, supply pressure to the Number 1 System?

Number 2 System?

Back 11

1 System - Pumps 1 & 3
#1 - Mechanic Pump # 3 Electrical Pump

2 System - 2 & 4
Both Mechanical Pumps

Front 12

What type of pumps are the Mechanical Pumps on the AW139 Hydraulic System?

What Pressure do they operate at?

Back 12

Mechanical Pumps - Constant Pressure /Variable Flow

Pressure = 207 bar or 3000PSI

Front 13

What pressure does the Electrical Hydraulic Pump operate at on the AW139?

What cause the reduction in pressure as the Flight Controls are checked during Preflight?

Back 13

Electrical Pump Pressure - 105 Bar 1500 PSI

Pressure fluctuates during Preflight Checks due to the limited volume that the electrical pump can supply.

Front 14

Where is the #1 Mechanical Pump Located on the AW139?

# 2 Mechanical Pump?

Back 14

#1 Mechanical Pump Located - At the top of the #1 Engine Driveshaft Input on the Main Transmission

The Same Location on the #2 Engine Driveshaft Input.

Front 15

Where is the # 4 Mechanical Hydraulic Pump Located on the AW139?

Back 15

#4 Mechanical Hydraulic Pump Located - On the forward section of the Main Transmission Housing above the Oil Sight Glass.

Front 16

What does LGCV stand for ?

Back 16

LGCV = Landing Gear Control Valve

Front 17

What is the Time Limit on the Electrical Hydraulic Pump?

What is the reason it is limited?

Back 17

Elect Pump Time Limit = Automatic @ 2 minutes

For Battery Protection.

Front 18

Are there any differences between Hydraulic Pump 1 and pumps 2 & 4 on the AW139?

Back 18

Pump Differences 1, 2, 4,

No they are all the same pump type in pressure and flow.

Front 19

How many Level Switches are in each PCM in the AW139?
What Levels do they Indicate?

Back 19

PCM Fluid Level Switches = 3 Each

Levels Indicated :
50%
28%
22%

Front 20

How many filters are on each PCM assembly ?

Which one has a CAS or Input to the synoptic Page?

Which One has a Bypass?

Back 20

Hydraulic Filters PCM

-2 Each - 1 Press 1 Return
-The Return filter has a "clogged" input to the MAU
-The Return Filter has a Bypass that triggers the CAS input.

Front 21

What SOV's does the switch on the Hydraulic Control panel control?

What SOVs do the Level Switches in the PCM's control?

Back 21

Hydraulic SOV Control Panel - Controls the Flight Control Hydraulic SOV's

The Level Switches perform automatic functions based on the levels for the Utility SOV's.

Front 22

Where is the Pressure Sensor for the respective Hydraulic System Located?

The Temperature Sensor

Back 22

Hydraulic Pressure Sensor is located after the Pressure Filter Before the SOV

The Temp Sensor is located in the Return line to the PCM Resevior

Front 23

What is the purpose of the Hydraulic SOV switch on the control panel:
Central Position?
On Ground Closed either 1 or 2 ?
In Flight Closed Either 1 or 2?

Back 23

Hydraulic SOV Switch :
Central Position = System automatically controls for anomalies
Ground Closed = Isolate for Preflight check or Maintenance
Flight Closed = manually Isolate anomalies in temp or press or operation.

Front 24

What is the Temp and Press at which the Hyd Temp or Press CAS and annunciator on the control panel will illuminate?

Back 24

Hydraulic Temp CAS & control Light = 134C
Hydraulic Press CAS & Controller Light = 163bar

Front 25

If the MAU fails is the Hydraulic synoptic page information valid?

Back 25

NO

Front 26

In the #1 Hyd System Explain the Function and resultant automatic response by the MAU to a decrease in fluid level:
22%
Level in #2 Decreases to 22% as well?

Back 26

#1 Fluid Level 22%:

Utility SOV Closes no emergency landing gear extend

#2 drops to 22% as well:
#1 Flight SOV is locked open to prevent loss of Tail Rotor boost when #2 system closes TRSOV.

Front 27

In what condition is the Flight Control SOV utilized by the pilot in flight?

Back 27

Hydraulic System Over temp.

Front 28

What happens automatic functions occur when the #2 Hydraulic Reservoir reaches a 50% Level?

Back 28

#2 Level 50%

The # 2 Utility SOV closes disabling the normal Landing gear extension and pressure to hold the gear up.

Front 29

What Happens when the #2 Hydraulic Reservoir reaches 28%?

Back 29

#2 Level at 28%

#2 Utility SOV reopens and the TRSOV will be closed.

Front 30

What happens when the # 2 Hydraulic Reservoir continues to decrease to 22%?

Back 30

# 2 level 22%
#2 Utility SOV recloses disabling normal function of gear
TRSOV remains Closed

Front 31

When the Elect Hydraulic Pump is being used for flight control checks during preflight, what 5 CAS messages should be displayed?

What lights on the Control Panel?

Why?

Back 31

CAS Messages during preflight check using Elect Pump:
1-2-4 HYD PUMP.
1-2 SERVO
1-2 HYD PRESS
HYD UTIL PRESS
EMER LDG PRESS
Control Panel - Elect Pump On and Hyd PRESS =ON
The 105 bar from electrical pump is a failed amount of pressure in the MAU's logic.

Front 32

What affect will a single failed pump either 2 or 4 have on the Hydraulic System?

What CAS Message will be Displayed?

Back 32

The system will operate normally with all pressures at 207bar and all SOV's open as normal.

CAS Message = 2 HYD PUMP The controller will have no annunciators.

Front 33

What affect will a Failed #1 Pump have on the Hydraulic System?

What CAS Messages will be displayed?

Back 33

#1 Pump Fail
-Utility SOV will remain Undetermined Status
- Flight Control SOV Undetermined Status
- Flight Controls for #1 Considered Failed
- Emergency Landing Gear not Available
#2 side operates normally.
CAS = 1 HYD PUMP, 1 HYD PRESS, 1 SERVO, EMER LDG PRESS

Front 34

Why is there a HYD UTIL PRESS CAS Message when the # 2 System level drops to 50%?

Back 34

The Utility SOV #2 Closes and the pressure drops to 0 at the press sensor and the gear free falls due to lack of pressure.

Front 35

What causes the 2 SERVO CAS Message when the #2 Fluid Reservoir reaches 28%?

What changes are displayed on the Synoptic Page?

Back 35

The TRSOV Closing cause the 2 SERVO CAS

Hydraulic Synoptic pages displays TRSOV Closed as well as the TR Actuator and Main Rotor Actuators in Yellow caution outline

Front 36

What state will cause the
2 SERVO
HYD UTIL PRESS
2 HYD MIN
CAS Messages to be displayed?
What will the Hydraulic Synoptic Page display?

Back 36

#2 Fluid Level Reaches 22%

Synoptic Page will display
#2 Utility Closed - Gear Falls
#2 TRSOV Closed
All Flight And TR & LDG Servos shown Caution Yellow

Front 37

What indication and CAS messages will be displayed if the #1 Hyd Reservoir drops to 50% or even 28%

Back 37

#1 Level At 50%
CAS Messages = None
Synoptic Page = Amber Caution and level displayed 50% or 28% on # 1 reservoir.

Front 38

What are the CAS Messages associated with the #1 Hydraulic Reservoir reaching 22%?

Back 38

#1 22%
CAS = 1 HYD MIN for level at minimum
EMER LDG PRESS to indicate that Emergency landing gear extension is no longer available.

Front 39

What is the first reaction to any malfunction in the Hydraulic system that begins to close SOV's or display CAS Messages?

Back 39

Extend and lock the gear in the down position.

Front 40

What condition would cause the following CAS Messages
2 HYD TEMP
2 HYD OIL PRESS
2 SERVO

Why?

Back 40

# 2 Hydraulic System Overheat
Temp Exceeds 134C and the MAU shuts down both the Flight Control SOV and TRSOV to try and cool the system.
Note the Utility SOV remains open as because the gear are not moving back and forth adding heat to the system.

Front 41

What critical note restriction is present when there is a temp fault in one system and a servo fault in the opposite system?

What dangerous condition could result?

Back 41

DO not close the overheated system to cool if the servos on the opposite side are illuminated amber and a 1-2 SERVO caution is displayed.

The overheated servos being removed to allow them to cool may leave you with unreliable servos in the opposite system and control lock cold occur.