Pneumatic, Air Conditioning And Pressurization Flashcards
What sources of pressurized air are available for the air conditioning/environmental system?
Engine bleed, APU bleed, and external air cart
When does the CABIN ALTITUDE CAS illuminate if the destination altitude is below 7850’?
Caution(amber) at 8500’; Warning(red) at 9400’
Flying into Telluride (KTEX), how does the CABIN ALTITUDE WARNING HIGH (A) CAS affect CABIN ALTITUDE (C) and (W)?
Increases CABIN ALTITUDE caution to Field elevation +650’; Increases CABIN ALTITUDE warning to Field Elevation +1550’
What is the IASC and how many are there?
Integrated Air System Controller – controls all pneumatics (Environmental and Anti-ice) and leak monitoring - 2 controllers each with 2 channels
How many outflow valves are installed?
1
Where is the outflow valve located?
Below the right wing leading edge, Behind right landing light
How is the outflow valve opened and closed?
Electrically by servo motors
How many safety valves are installed and where are they located?
Two on the aft pressure bulkhead
What is the function of the safety valves?
To provide overpressure and negative pressure relief
Do the safety valves require electrical power to operate?
No, they are pneumatically operated, and spring loaded closed
Does the environmental system use IP air or HP air?
IP (Intermediate Pressure) …regulated to ~ 50 psi
Most valves in the bleed and air conditioning system are controlled and actuated by?
Electrically controlled and pneumatically actuated
What two valves are electrically actuated?
Outflow valve and avionics cooling valve
What conditions cause the IP bleed valves to be closed?
Fire switch PBA, Loss of bleed pressure to valve, electrical power loss to valve, engine start
What does the Ozone Converter do?
Converts the Ozone from the IP bleed air into oxygen to combat fatigue and dehydration
When the START switch is selected, what happens to the Flow Control Valves?
They automatically close to shut down the air conditioning system allocating all bleed air to the engine starter (ATS)
When does the ditching switch become active?
Below 15000’ the outflow valve opens on a depressurizing schedule
What does Ram air do?
Provides cooling air to the air heat exchangers and for cabin ventilation at low altitudes (<10000) if the pack and trim air fail or unpressurized flight is required
Is the trim air cold or hot air?
Hot air
What is pack air?
Colder air
Pressing the Emer Depress switch does what?
When in AUTO mode - Cabin depressurizes at 2500fpm to 14000ft ±100ft or aircraft altitude, whichever is lower; When in MANUAL mode - Cabin depressurizes at 3000fpm to 14500ft ±500ft or aircraft altitude, whichever is lower
How is temperature controlled in ‘Auto’ mode?
Ventilated temp sensors in the cockpit and cabin input to the IASC’s to regulate set temperature
How is temperature controlled in ‘Manual’ mode?
Direct control through the IASC’s to regulate the temperature
The temperature ‘Pull up/Pull down’ works under what conditions?
APU or Pneumatic cart air pressure is available, Air source = Normal, Temp mode = AUTO, main cabin door not closed, and more than 10 O difference between selected and indicated temperature
What modes of pressurization operation are there?
3 Total modes: 2 in ‘Auto’ through IASC’s #1 and #2, 1 in ‘Manual’ direct control of outflow valve via rate knob (max. 3000 fpm)
What are the indications when an external air cart is being used?
ECS and summary pages indicate bleed pressure in the right and left side of the manifold. No green ‘flow lines’
Where do you find ‘X-Bleed’/’External Air Cart’ start procedures?
QRH Volume 1 – Supplemental Data tab, S-51-1
How do you set landing altitude manually while in Auto Press mode?
Landing alt outer knob to manual and inner knob to select alt in 20 ft increments (cyan indication)
