Hydraulic¶
Hydraulic: 1 General¶
The aircraft has two hydraulic systems: blue and green.
Hydraulic: 2 Power Generation¶
The common hydraulic tank is in the hydraulic bay (LH landing gear fairing).
BLUE COMPARTMENT 4 l GREEN COMPARTMENT 4 l TOTAL FLUID VOLUME 9.6 l MINIMUM FILLING LEVEL 8.5 l NORMAL FILLING LEVEL 9.35 l ALERT LEVEL 2.5 l DIRECT-FLUID LEVEL READING SIGHT-GLASS The hydraulic tank is a direct air-fluid contact type and is not pressurized. A sight glass is fitted on the tank for direct-reading of fluid level. The tank is internally divided in two equal compartments (green and blue) by a diaphragm and open in the upper side to allow simultaneous refilling. A compartment baffle avoids fluid splashing and reduces foaming. Each compartment has a low level alert triggered when fluid quantity drops below 2.5 l. Each system is pressurized by an electrical hydraulic pump powered by ACW. The blue circuit is fitted with an additional DC driven auxiliary pump. The auxiliary DC electric pump automatically provides hydraulic power to operate the users of the blue system if the ACW pump fails. A momentary ground switch located on the pedestal enables to energize the auxiliary pump manually. This momentary ground switch will operate the DC auxiliary pump for:
- as long as the switch is pushed when the Aircraft BAT toggle sw is OFF.
- 30 seconds when the BAT toggle sw is ON and the Aircraft is electrically supplied (GEN or EXT PWR ) . Both ACW main hydraulic pumps and the DC auxiliary pump have a nominal output pressure of 3 000 psi. Each system has a 0.2 l power accumulator installed in the hydraulic bay. The accumulators reduce pumps vibrations and pressure surges. They also compensate for the pump response lag-time when the output demand is high. On ground, when electrical power is not available, the hydraulic system can be pressurized through a ground hydraulic power unit. The connector for the ground hydraulic power unit is on the Ground Service Panel in the hydraulic bay. A ground switch on the center pedestal enables the supply of energy to the auxiliary pump even if electrical power is not available.
Hydraulic: 3 Supplied Systems¶
- The blue system supplies: o Wing flaps extension/retraction (four hydraulic jacks) o Spoilers (two hydraulic jacks) o Nose wheel steering (one hydraulic jack) o Propeller brake for the RH engine o Emergency and parking brakes for the four wheels of the main landing gear, through a specific accumulator with separated pressure indicator.
- The green system supplies: o Landing gear extension/retraction:
- Three hydraulic jacks
- Three actuators for uplock release
- Three actuators for lock down release. o Normal brake for the four wheels of the main landing gear. In case of one hydraulic pump failure, the other pump can supply the associated systems if the flight crew opens the crossfeed valve. Note In case of LO LVL alert, the crossfeed valve:
- Remains closed, if it was in closed position
- Automatically closes, if it was in opened position.
Hydraulic: 1 HYD PWR Panel¶
14, 0, 4, 3 V13.2 L_CB_00000000_0000000_000_00_00
- Fig. 1 : Hydraulic CP Shadow -
OFF LO PR OVHT BLUE PUMP AUX PUMP GREEN PUMP X FEED LO LVL OFF LO PR 26VU HYD PWR EMER BRK SPLR FLAPS PROP BRK N/W STRG NORM BRK LDG GEAR 1 2 5 1 3 4 5 OVHT OVHT LO LVL ON OFF LO PR 4 - Fig. 2 : Hydraulic Power Panel - 1 Main Pumps pb The main pumps pb control the activation/deactivation of pumps powered by ACW electric motor. (pb pressed in) Activates pump. OFF (pb released) deactivates pump, OFF light comes on white. LO PR The light comes on amber and the caution message "HYD BLUE (GREEN) LO PR" from FWS appears on EWD associated with a Master Caution light and a Single Chime, when the fluid pressure of the associated pump decreases below 1 500 psi.
2 Auxiliary Pump pb The auxiliary pump pb controls operating mode of DC auxiliary pump. AUTO (pb pressed in) runs pump as soon as: - Pressure of ACW blue pump is below 1 500 psi - Propeller brake is released - Gear handle is selected DOWN - At least one engine is running. OFF (pb released) deactivates auxiliary pump, OFF light comes on white. LO PR The light comes on amber and a caution message from FWS appears on EWD associated with a Master Caution and a Single Chime when the outlet pressure of the auxiliary pump decreases below 1 500 psi and operating conditions are established. 3 X FEED pb The crossfeed pb controls the position of the crossfeed valve. (pb released) Closes the crossfeed valve and separates both hydraulics circuits. ON (pb pressed in) opens the crossfeed valve and connects both hydraulic circuits. ON light comes on blue. 4 OVHT Lights The OVHT light comes on amber and the caution message "HYD BLUE (GREEN) OVHT" from FWS appears on EWD associated with a Master Caution and a Single Chime, in case of overheat detection (T > 121 °C) in the associated drain line of the pump housing. 5 LO LVL Lights The LO LVL light comes on amber and the caution message "HYD BLUE (GREEN) LO LVL" from FWS appears on EWD associated with a Master Caution and a Single Chime, when fluid quantity in the associated tank compartment decreases below 2.5 l. The crossfeed valve automatically closes.
Hydraulic: 2 Hydraulic Auxiliary Pump Switch¶
AUX HYD GND CTL ONLY PUMP
Hydraulic Auxiliary Pump Switch The auxiliary pump switch activates for 30 s the auxiliary hydraulic pump and enables it to operate in manual mode. CAUTION This switch operates even when batteries master sw is selected OFF. Intensive use discharges the main battery. This switch functions is used only when aircraft is on ground. Note It is recommended to not use the hydraulic auxiliary pump before hydraulic pressure check.
Hydraulic: 3 MFD Indications¶
Hydraulic indications appears on the ACW/HYD page of the MFD.
MFD - Fig. 1 : Pressure Indication Shadow -
X FEED AVAIL EXT PWR ON BTC TRU 3000 PSI NORM BRK LDG GEAR EMER BRK ACCU FLAPS SPOILERS PSI 3000 STRG N/W PROP BRK 3000 PSI ACW BUS 1 DC STBY FAULT ACW GEN1 AUX HYD DC BUS 2 FAULT ACW GEN2 ACW BUS 2 GREEN HYD BLUE HYD OVHT LO LVL 1 2 8 4 5 6 7 3
- Fig. 2 : Pressure Indication -
AUX PUMP pb on low hydraulic pressure ITEM DISPLAY DESCRIPTION 1 If pressure above 1 500 psi Dash appears in case of invalid data If below or equal 1 500 psi 2 3 4 3000 PSI - - - - PSI PUMP pb on normal hydraulic pressure PUMP pb OFF OFF PR LO PUMP pb on low hydraulic pressure AUX PUMP pb on normal hydraulic pressure OFF STBY If AUX PUMP pb released white "OFF" indication If AUX PUMP pb pressed in green "STBY" indication when pump not running PR LO STBY AUX PUMP indication in case of electrical power failure DC BUS 2 Normal operating MAIN BAT Emergency power ITEM DISPLAY DESCRIPTION XFEED closed Text(s) in normal operation Oil temperature in the drain line of the pump housing > 121 °C 5 6 7 INHIB XFEED open Inhib legend appears if XFEED is inhibited after a LO LVL alert OVHT LO LVL Fluid level in the tank decreases below 2.5 l FLAPS SPOILERS STRG N/W PROP BRK Text(s) in case of system low pressure FLAPS SPOILERS STRG N/W PROP BRK 8 112 PSI
- Fig. 3 : Pressure Indication Legend -
Hydraulic: 1 Electrical Supply¶
EQUIPMENT DC BUS SUPPLY (C/B) AC BUS SUPPLY (C/B) Blue pump power NIL ACW BUS 1 (on lateral panel C/B BLUE HYD PUMP PWR SPLY) Blue pump control DC EMER BUS (on lateral panel C/B BLUE PUMP CTL) NIL Blue system alert DC EMER BUS (on lateral panel C/B CAUTION BLUE SYS) NIL Green pump power NIL ACW BUS 2 (on lateral panel C/B GREEN HYD PUMP PWR SPLY) Green pump control DC ESS BUS (on lateral panel C/B GREEN PUMP CTL) NIL Green system alert DC EMER BUS (on lateral panel C/B CAUTION GREEN SYS) NIL Auxiliary pump power DC BUS 2 (on lateral panel C/B AUX HYD PUMP NORM PWR SPLY) HOT MAIN BAT BUS (on lateral panel C/B AUX HYD PUMP GND PWR SPLY) NIL Auxiliary pump control DC BUS 2 (on lateral panel C/B HYD PWR AUX PUMP CTL & IND NORM) HOT MAIN BAT BUS (on lateral panel C/B AUX PUMP CTL & IND GND) NIL Pressure indicator DC EMER BUS (on lateral panel C/B PRESS IND) NIL X FEED valve DC STBY BUS (on lateral panel C/B X FEED) NIL
Hydraulic: 1 HYD BLUE (GREEN) LO LVL-Alert¶
CONDITION VISUAL AURAL Tank compartment fluid quantity below 2.5 l - MC light flashing amber - HYD BLUE (GREEN) LO LVL amber message on EWD - LO LVL amber message on ACW HYD SD - Associated LO LVL amber light on overhead panel SC
Hydraulic: 2 HYD BLUE (GREEN) LO PR-Alert¶
CONDITION VISUAL AURAL Pump delivery pressure below 1 500 psi - MC light flashing amber - HYD BLUE (GREEN) LO PR amber message on EWD - LO PR amber message on ACW HYD SD - Associated pump LO PR amber light on overhead panel SC
Hydraulic: 3 HYD BLUE (GREEN) OVHT-Alert¶
CONDITION VISUAL AURAL Pump housing drain line temperature above 121 °C - MC light flashing amber - HYD BLUE (GREEN) OVHT amber message on EWD - OVHT amber message on ACW HYD SD - Associated OVHT amber light on overhead panel SC
Hydraulic: 4 HYD AUX LO PR-Alert¶
CONDITION VISUAL AURAL Pump delivery pressure below 1 500 psi - MC light flashing amber - HYD AUX LO PR amber message on EWD - AUX HYD LO PR amber message on ACW HYD SD page - AUX PUMP LO PR amber light on overhead panel SC
Hydraulic: 5 HYD AUX OVHT-Alert¶
CONDITION VISUAL AURAL Pump housing drain line temperature above 121 °C - MC light flashing amber - HYD AUX OVHT amber message on EWD - OVHT amber message on ACW HYD SD - AUX PUMP OVHT amber light on overhead panel SC
Hydraulic: 6 HYD BLUE AND GREEN PUMPS LOSS-Alert¶
CONDITION VISUAL AURAL Loss of hydraulic pump information - MC light flashing amber - HYD PUMPS LOSS amber message on EWD SC
Hydraulic: 7 HYD BLUE AND GREEN SYS LOSS-Alert¶
CONDITION VISUAL AURAL Loss of both hydraulic systems - MC light flashing amber - HYD SYS LOSS amber message on EWD SC
Hydraulic: 1 Parking-Emergency Braking Accumulator¶
In addition to the PRKG BRK ON annunciation on EWD and the Parking / Emergency Braking Accumulator display on MFD ACW/HYD page, the aircraft has a Parking / Emergency Braking Accumulator pressure indicator on the left maintenance panel.
OFF ON ONLY WHEN NORM IND LOST BRAKE ACCU HYD PSI x 1000
The pressure of the Brake Accumulator appears in green. Multiply the value by 1 000 (as indicated by the legend on the front face). The switch activation energizes the indicator for 2 min. When the hydraulic pressure of the accumulator is below 1 700 psi or above 3 100 psi, the indicator displays blank.
Maintenance uses the indicator when MFD is not activated and in the case of main indication loss.
Hydraulic: 1 Schematics¶
BRAKE ACCU HYD.SYST PSIx1000 B G 1 1 1 2 3 3 2 3 2 0 0 0 M LO PR OFF BLUE PUMP M M NOSE WHEEL STEERING LANDING GEAR FLAPS SPOILERS EMERG & PARKING NORMAL BRAKING OVHT LO LEVEL LO LEVEL OVHT LO PR ON AUX PUMP OVHT ON X FEED LO PR OFF GREEN PUMP RETURN PROPELLER BRAKE
COMMON RESERVOIR
/ \
BLUE COMPARTMENT GREEN COMPARTMENT
| |
+--------+--------+ +--> [GREEN PUMP]
| | |
[BLUE PUMP] [AUX PUMP] |
| | |
+-------- BLUE PRESSURE ----[X-FEED]---- GREEN PRESSURE
| |
| +--> LANDING GEAR
| +--> NORMAL BRAKING
+--> NOSE-WHEEL STEERING
+--> FLAPS
+--> SPOILERS
+--> PROPELLER BRAKE
+--> EMERGENCY/PARKING BRAKING accumulator
Pressure transmitters monitor both systems and the brake accumulator. Return
flow from both systems routes to the common reservoir.