Systems Guide

A318/A319/A320/A321
Professional
SYSTEMS
Systems guide
Vol
4
04-03-7
11 July 2018
PRESSURIZATION
Under normal operation conditions the complete pressurization is fully automatic. The system consists of:
• two Cabin Pressure Controllers
• outflow valve
• control panel
• two safety valves
In automatic operation pressurization is divided in 6 different modes
• Ground: before take-off and 1 minute after landing the outflow, valve is fully open to equalize
pressure with outside pressure.
• Take-off: just before take-off the system pre-pressurizes the cabin to avoid a sudden pressure
increase
• Climb: cabin altitude is decreased to cruise level using input from vertical speed and other
sensors
• Cruise: cabin pressure is maintained
• Descent: cabin altitude is increased to cruise level using input from vertical speed and other
sensors
• Abort: in case of an aborted take-off the system will prevent the triggered climb mode from
starting to decrease the pressure.