Systems Guide

Aerosoft
Airbus A320/A321
SYSTEMS
Systems guide
Vol
4
04-03-50
28 October 2014
HYDRAULIC SYSTEM
GENERAL
There are three separate and fully independent hydraulic systems, Green, Blue and Yellow, each with its own
pump(s), reservoir and accumulator. In normal operation the system is fully automated and does not need any
interaction.
 The Green system can be pressurized by an engine-driven pump and can use the Yellow system via the
connection Power Transfer Unit (PTU).
 The Yellow system can be can be pressurized by an engine-driven pump and can use the Green system
via the connecting PTU. Additionally an electric and a hand pump (not simulated) can be used.
 The Blue system is powered by an electric pump or the Ram Air Turbine (not simulated) and is mainly
intended as a backup emergency system.
 The Power Transfer Unit is used to transfer pressure between the Green and Yellow systems when
differential pressure exceeds a set limit.
ECAM HYD PAGE
All pumps are indicated by triangles on the ECAM. When the pump is off it is a white open triangle, when the
pump is ON and pressure is normal a green triangle is shown. An amber triangle means the pump is on but
pressure too low.
HYD OVERHEAD PANEL
The Hydraulic panel on the overhead panel allows the crew to interact with the system in case of failures. As with
all overhead panels a completely dark panel indicates is in AUTO mode and there are no problems.
 The ENG PUMP pb (ENG 1 PUMP & ENG 2 PUMP) are dark in AUTO mode (ON and pressure within
limits). When there is a problem FAULT will show. When pushed OFF will show and the pump will be
offline and the system depressurize.
 The Blue Electric Pump pb (ELEC PUMP) is always active when one of the AC buses has power. When
pushed (after lifting the switch guard) OFF will show and the system will depressurize. When the pump
is on but pressure too low FAULT will show. The ECAM will show more details on that.