Hydraulics Flashcards
Which components can pressurise the
GREEN System?
EDP1
&
PTU
Which Components can
pressurise the
BLUE System?
Blue Electric Pump
&
RAT
Which components can
pressurise the
YELLOW System?
EDP2
PTU
&
Yellow Electric Pump
Which components can the
Hand Pump
pressurise?
Cargo Door
actuators only.
When will the
PTU Operate?
When the difference between the
GREEN & YELLOW
systems exceeds
500 psi.
When is the
PTU inhibited?
- Aircraft is on GROUND, and
- Either: Park Brake is set,
- or NWS is in the towing position, and
- One Eng Master SW is ON, the other OFF.
- Also, it will not run within 40 secs of Cargo Door operation.
Does the RAT deploy
automatically
for any Hydraulic System
Failures?
No
What do the priority valves do?
Cut off hydraulic power to heavy users.
This preserves hydraulic power for
flight controls.
Hydraulic Reservoirs are pressurised.
Why?
This prevents cavitation at the
pumps.
Particularly at altitude.
When does the BLUE
electric pump
usually operate?
After First Engine Start
or
In flight with AC power available.
When does the YELLOW Electric Pump
normally operate?
- Switch in NORMAL Position - For Cargo Door Operation only.
- Switch in ON Position - It runs if AC Power is available.
What 4 faults cause
EDP1 or EDP2 FAULT lights
to illuminate?
- Reservoir Low Level
- Reservoir Overheat
- Reservoir Low Air Pressure
- Low Pump Output Pressure
If a FAULT light illuminates in a Pump
or the PTU pb, the PUMP/PTU is switched off.
What is the difference in sysytem response for
an OVERHEAT (fluid or pump)?
The FAULT light remains illuminated
until the system cools when
it will extinguish.
For other faults the FAULT light(s)
extinguish when the pb
is switched OFF.
Before Engine Start,
which hydraulic systems
can be pressurised?
ALL OF THEM
- Switch the YELLOW Elec Pump ON, this will pressurise the YELLOW system and GREEN via the PTU.
- Select the BLUE override pb ON, this will pressurise the BLUE system.
At what pressure is a
‘Low Pressure’
ECAM caution/Warning
triggered?
1,450 psi