Pneumatics Flashcards
(29 cards)
The APU provides bleed air up to what altitude?
20,000’
The bleed air ducts are constructed of what material(s)?
Stainless Steel
Titanium
Aluminum
High Pressure bleed air is routed through HP valves to …
Wing Anti-Ice System
Intermediate Pressure bleed air is routed through IP valves to …
To the common manifold where the ECS system controls it
The bleed air manifold is located …
In the engine pylons and aft equipment bay
Both the APU and ground air cart supply air to what side of the cross bleed valve?
Right Side
The IP valves are controlled by and operated by …
Electrically controlled by the L/R BLEED switches on the panel and pneumatically operated
The pressure regulating function of the IP valve limits engine discharge pressure to …
50 +- 3
L/R BLEED AIR caution occurs when …
IP valve fails and manifold pressure exceeds 60 psi
The IP valves are in a closed position when any occurs … (5)
Engine Shut Down
Power lost to the valves
ENG FIRE switch selected
Valves selected closed on the AIR COND/BLEED panel
During Engine start
The HP valves regulate engine high pressure bleed to …
36 +- 3 psi
The HP valves are controlled by and operated by …
WING SOURCE and WING switch electrically control the pneumatically operated valves
The HP valves are closed when any of the following occur … (4)
Engines Shut Down
Power lost to valves
ENG FIRE switch selected
WING anti-ice selected OFF
The APU bleed valve is controlled by …
The APU ECU (electrical control unit)
The amount of bleed air taken from the APU depends on …
APU exhaust temperature as determined by the ECU
The APU bleed valve is closed …
APU is shut down
Signal loss from the ECU
The IASC’s are located where …
One is under the floor
One is under the liner of the lavatory above the floor
Describe the function of the IASC’s
The units gather air conditioning and bleed air control functions and monitor cabin pressure and airframe ice protection functions
IASC 1 monitors …
Left HP valve and left IP valve
IASC 2 monitors …
Right HP valve and right IP valve
Each IASC consists of 2 channels that monitor …
Channel A - environmental control system and cabin pressure control
Channel B - wing anti-icing monitoring and control along with leak detection
When the L/R STARTER switch is positioned to start, what occurs relative to the pneumatic system … (4)
Cross-bleed valve opens (if previously selected closed)
Flow control valves close (if previously open)
Associated start valve opens
Engine ATS engages
A BLEED LOOP FAULT occurs if …
One loop of a dual loop system has failed
A BLEED LOOP FAIL occurs if …
Both loops of a dual loop system have failed. Will also occur when a single-loop system has failed
