Pressurization Flashcards
How is pressurization achieved?
By regulating amount of air leaving
aircraft through TROV
How is control of CPCS page of TSC
affected by pressurization system
mode of operation?
In Auto mode, Aircraft Altitude, Cabin
Altitude, Baro Corr, Landing Elevation,
and Rate Limit is viewed on CPCS page.
In Semi mode, this data can be changed.
What’s the meaning of amber FAULT
light on the CABIN PRESSURE
CONTROL panel?
It indicates failure of both CPCU 1 and 2:
you’d have to select MANUAL
When does system automatically
switch to Flight and begin to pre-
pressurize cabin prior to takeoff?
Initiated if doors are closed and any of the
following occur: switch is selected to
Flight, airplane begins to move > 9 knots
or throttles are advanced
What happens in-flight when Landing
is selected on Pressure Profile switch?
Cabin pressure control system
automatically switches to descent
pressurization schedule (i.e., 300 fpm).
When does the Pressure Profile switch
automatically switch to Landing?
When aircraft descends from cruise at
least 1,000 feet
When would you use the semi-
automatic (Semi) mode?
Whenever FMS data is not available or is
invalid, when directed by checklist, or at
discretion of flight crew (e.g., flying to
high altitude airport).
What’s one benefit of flying in Semi
mode?
You have more control over the system
What’s the purpose of MANUAL
mode?
Used to manually control TROV and may
be used as backup method if CPCU 1 and
2 fail
What’s the purpose of pressure relief valve?
It provides rate-limiting function to
prevent damage to aircraft fuselage from
excessive positive or negative pressures.
What type of action does the system
perform after landing to ensure
minimal differential pressure exists
within the cabin?
During ground operations when TROV is
full open, pressure relief valve is forced
open with bleed air
When would pressure relief valve start
to relieve pressure?
There are two (2) pneumatic chambers:
one relieves at 10.80 differential pressure
and the other relieves at 11.00
What’s the trip point for red Cabin
Pressure Low CAS message?
Landing field elevation
What are the prerequisites for
Emergency Descent Mode (EDM)?
Cabin Pressure Low CAS message
Aircraft altitude ≥ FL400
Autopilot engaged
Describe aircraft operation in EDM.
Speed target on guidance panel changes to
340 KCAS in manual mode, altitude
preselect is set to 15,000 feet,
APcommands a left 90° heading change in
heading hold mode, and A/T decreases
engine throttles to idle.
If not engaged, A/T automatically engages and decreases engine throttles to idle.
Airplane descends to MMO/VMO to 15,000 feet and speed brakes automatically extend.
At 15,000 feet, speed target changes to 250 KCAS.
Override EDM by disconnecting AP.
