Air Systems Flashcards
What stages of the compressor section is bleed air drawn from?
Engine bleed air is obtained from the 4th and 10th stages of the compressor section.
What provides pressure and temperature regulation for the bleed air?
The engine bleed air valve acts as a pressure regulator and shutoff valve.
The valve maintains proper system operating pressure and reduces bleed air outflow in
response to high bleed air temperature.
What happens if over-temperature or over-pressure is sensed?
Bleed sensors illuminate the respective BLEED light when engine bleed air temperature or pressure exceeds a predetermined limit. The respective engine bleed air valve closes automatically.
What would cause both BLEED lights to come on after takeoff or go around?
both BLEED lights illuminate if an incorrect bleed configuration is present after takeoff or go-around
When does the ISOL open in the AUTO position?
The isolation valve opens if either engine bleed air switch or air conditioning pack
switch is positioned OFF. Isolation valve position is not affected by the APU bleed air switch.
Why is it important to keep the engines at idle when ISOL OPEN, EBV ON and APU BLEED ON with APU running?
To avoid back pressure in the APU
What causes Wing Body Overheat?
A wing-body overheat condition is caused by a bleed air duct leak.
Which PACK supplies air to the Flight Deck / Cabin?
Conditioned air from the left pack, upstream of the mix manifold, flows directly to the flight deck. Excess air from the left pack, air from the right pack, and air from the recirculation system is combined in the mix manifold. The mixed air is
then distributed through the left and right sidewall risers to the passenger cabin.
Is it possible to fly to the certified ceiling with 1 PACK operating?
YES
When and why would PACK high flow be inhibited?
automatic switching to high flow is inhibited when the airplane is on the ground, or inflight with the flaps extended, to ensure adequate engine thrust for single engine operation.
How are the PACKs cooled?
Ram air
What would cause the PACK light to illuminate?
An overheat condition
When can the PACK light be reset using the Trip Reset Switch?
When directed by QRH. To reset if tripped from and overheat condition
Will the pilot be alerted if the primary flight deck temperature control fails?
No. Only after landing
What happens automatically if smoke is detected in the E & E bay?
When smoke is detected the system will automatically set the packs to high flow, turn the E/E Cooling Supply Fan(s) OFF for approximately 5 minutes, overboard exhaust valve opens to the smoke position and the recirculation fans turn off.
