Pneumatic/Air Conditioning/Pressurization Flashcards
What is the maximum permitted cabin pressure differential in flight?
9.8 psid
What is the maximum permitted cabin pressure differential for taxi, takeoff or landing?
0.3 psid
What cabin altitude will cause the passenger oxygen masks to deploy?
13,000 FT (+/-500) Cabin Altitude
What are the Cabin Pressure Controller power sources:
-in Auto?
ESS AC (Phase A)
What are the Cabin Pressure Controller power sources:
- in Manual
ESS DC
What functions does the Cabin Safety Relief Valve provide?
· Positive differential pressure relief at 9.7 + 0.1 psi
· Negative differential pressure relief at -0.25 psi
· Rate Limiting: 3000’/min
What is the temperature range selection in AUTO?
AUTO = 60 - 80 degrees F
Four conditions that will cause the Isolation Valve to open?
· Isolation Valve selected ON
· APU Bleed Air switch selected ON
· Master Crank selected ON
· Master Start selected ON
What are four conditions will cause the pack valves to close?
- Pack switch selected - OFF
- Either engine start switch selected – ON
- Ram air switch selected to RAM • COOL TURB HOT caution message (ground only)
What is the maximum altitude that one Engine Bleed Switch can be selected off?
41,000 feet
- What are the 3 operational modes of the pneumatic system?
Pressure regulated mode (dual pack mode) – 18 to 40psi
Temperature regulated mode – cowl and wing anti ice on
Single pack operation – 10 – 40 psi
- What is the purpose of the isolation valve?
Eliminates problems of two engine flow sharing and
Allows availability of all pneumatic systems with one bleed air turned off
- What is the corrective action for a red “PYLON HOT” CAS message?
Turn the appropriate bleed air switch OFF
- What is indicated by an amber “BLEED PRESS HI” CAS message?
Bleed air pressure in the manifold has exceeded 75 psi
- What is indicated by an amber “BLEED AIR HOT” CAS message?
Bleed air temperature in the manifold has exceeded 550º F
