Pressurization Flashcards
How many outflow valves are there
Two
How many independent pressure controllers are there?
Two CPAMS
Upon landing the aircraft depressurizes after _____?
60 Seconds - outflow valves command full open
The pressure controller (CPAM) switches from standby
3 minutes after landing
Outflow valves are controlled ____ ?
Electronically
Outflow valves are operated ____ ?
Neumatically
What is the safety feature of the outflow valves?
The built in safety valves open automatically at 8.6 psi and a negative pressure of -.5 psi.
During manual pressurization control which outflow valve is controlled
The secondary outflow valve is directly controlled by the manual selection on the control panel.
In Manual Mode where is the information shown?
Cabin Rate and Altitude can be found on the ECS, the Status and Primary page.
The EMER DEPRESS switch does what?
Depressurizes the aircraft to 14,250’ +/- 750’
On the 700 limit climb to ____ above FL___?
1500 fpm above FL300
The CPAM receives information from what?
The standby pitot static system
True or False - The CPAM receives info from the primary pitot static system.
False - it receives it’s info from the standby pitot static system
How are the 700 / 900 pressure controllers different?
It only has one Pressure Controller with triple redundancy and 2 Safety Valves
The vacuum power required to regulate the outflow valves comes from where?
A Jet Pump off the 10th stage bleed air system.
What happens when a differential pressure of 8.6 psi is sensed by the CPAM
a “CABIN PRESSURE” aural warning with a “DIFF PRESS” warning message. The outflow valves will open to relieve the excess pressure.
During normal operation the primary valve is controlled by what? And the secondary valve is controlled by what?
The CPC1 controls the primary valve and the CPC2 controls the secondary valve. They are slaved to each other.
What happens to the secondary valve in Manual Mode?
The secondary valve becomes the primary valve in Manual Mode, with the primary valve slaved to it.
What does Manual Mode do?
the secondary valve becomes primary and it is controlled directly by manual selection on the control panel.
How many CPC’s on the 200?
Two
How many CPC’s on the 700 / 900?
One
CPAM illuminates the NO SMOKING / FASTEN SEAT BELT sign when…
when the cabin altitude is greater than 10,000’
What should you do if the aircraft becomes inadvertently pressurized on the ground via the low pressure air?
Do not open the door!!! Start the APU and use the EMER DEPRESS switch.
Main 700 / 900 Differences
Only One Outflow Valve with triple redundancy electric motors with Two Safety Valves.
If the CPAM fails, will the O2 Masks drop.
No, but there will be a CABIN PRESS warning message will be generated along with the aural “CABIN PRESSURE” message.
At what cabin altitude does the CPAM drop the masks?
14,000’
What does the flight abort mode do on the CRJ 700 / 900
It maintains the pre pressurization altitude for the first 10 minutes
What is the difference of outflow valves on the different variants
The CRJ 200 has 2 outflow valves
The CRJ 700 / 900 have only one outflow valve
How are the 2 outflow valves controlled on the CRJ 200
Controlled by either of two independent cabin pressure controllers.
Upon landing in the CRJ 200 what happens to the pressurization system?
After 60 seconds WOW the outflow valves are commanded full open
After 3 minutes the standby controller becomes the active controller for the next flight.
The outflow valves on the CRJ 200 are _____ controlled
and _____ operated
the outflow valves are electrically controlled and pneumatically operated
How are the outflow valves pneumatically operated on the CRJ 200
A jet pump off the 10th stage bleed air system provides vacuum power required to regulate the outflow valves
What happens when cabin pressure differential reaches 8.6 psi on the CRJ 200
An Aural “CABIN PRESSURE” warning
with a “DIFF PRESS” warning message on the EICAS
What is the difference between the 2 outflow valves on the CRJ 200
They are identical except the secondary valve has bent lines that connect it directly to the manual pressurization control panel
In manual mode, how is pressurization controlled in the CRJ 200
In manual mode, the secondary outflow valve is directly controlled with the primary valve slaved to it, via the jet pump which modulates the secondary outflow valve
When Manual mode is selected on the pressurization control panel on the CRJ 200 where is the information presented?
ECS page
Status page
Primary page
If the CPAM fails on the CRJ 200, will the PAX 02 MASKS drop when cabin altitudes reach 14,000 ft
NO
The outflow valve on the CRJ 700 / 900 is _____ operated
Electrically Operated via DC power
What do the safety valves on the CRJ 700 / 900 do?
provide over pressure and negative pressure relief
How are the safety valves operated on the CRJ 700 / 90
they are pneumatically operated and spring loaded closed
