Crj Ac And Pressurization Flashcards
What does bleed air supply?
Ac-15000ft Pressure Tr,s Engine starting/ -13000ft Ice protection
How is cabin pressure regulated.
Outflow valves
How is the bleed system monitored?
Via an 10th and 14th bleed detection system. Detects leak and provides visual warnings.
Which engine provides air to the packs?
On side engine
Apu provides air direct to left pack and to right pack via isolation valve.
What is thd percent split between airflow from packs to cabin and cockpit.
Left 70% cockpit
Right 70% cabin
How is air heated and cooled for cabin comfort? Regulated.
A pack dual bypass valve regulates the air through the acm to cool it or around the acm to retain its heat. Then the temperature control valve modulates as necessary to blend bypass air with cooled acm air to achieve temp.
What does ram air do?
Aids pack cooling via a heat exchanger.
Unpressurized flight
How are crts cooled? Avionics?
Independent fans. Display cools crts
And arinc cools avionics.
Which fans operate when?
No 1 fan in flight
No 2 fan on ground
Standby is backup
Fans switch with wow
At rate rate does the cabin climb fof pressurization? Descend?
Climb 500fpm
Descend 300fpm
What does the cpam do?
Generates values for eicas
Deployed oxy masks and illuminates seat belt and no smoking signs at 14000 ft cabin altitude.
What happens if the cpam fails?
Standby cpc generates all indications but will not auto deploy oxy masks.
What are the pressurization auto modes?
Ground-outflow valves fully open
Takeoff-thrust advanced/cabin pressurized to 150 ft below field elev.
Abort-cabin depressurization at 500fpm for 20 secs then outflow valves fully open.
Emer return mode- if you maintain 6000 ft or less for less than 10 minutes and descends at 1000fpm or more it assumes landing is at departed airport.
What position do the bleed valves fail to?
Closed
Except 14th isol valve
What do the different modes on the cargo switch do?
Condair- recirculated air from dist. Manifold passes over an electric heater and maintains approx- 80*f
Fan-only cabin recirculated air, just above freezing
Off- airflow is shut off
