Pneumatics Flashcards
What is the primary function of the Precooler in the
pneumatic system?
Controls temperature of the engine bleed air entering the
bleed air manifold
APU bleed air can be used for which of the following?
Wing Anti-ice
What does the air crossfeed valve FAULT light mean?
Valve disagreement – not in position selected by switch
How can you manually open and close the air crossfeed valve?
Select Crossfeed Mode pushbutton switch to MAN, then
depress the X FEED pushbutton
What is not supplied by the aircraft pneumatic system?
Pneumatic cargo door operation
How do the engines supply bleed air to the pneumatic system?
Either the 8th or 15th stage compressor depending on engine
RPM
What pneumatic components are sourced directly from their
respective engines?
Engine Anti-ice and thrust reversers
Which engine normally supplies hydraulic reservoir
pressurization?
Number 1 engine
What is the function of the engine bleed valve?
Functions as a pressure regulator and shutoff valve
What happens if a BLEED VALVE pushbutton is selected off?
Engine and HP bleed valves are closed
When will a left or right BLEED LEAK light illuminate?
Overheat detected, remains illuminated as long as the
condition exists
Where does the hot air from the pneumatic manifold go after
passing through the pack valve?
Into the refrigeration unit or through the hot air supply valve
to the hot air manifold
What happens to the air crossfeed valve if electrical power is
lost?
The air crossfeed valve will remain in the last position selected
When do both engine bleed air valves automatically close?
The APU is supplying bleed air
The APU bleed air is switched ON how does the pneumatic
system reconfigure?
The Crossfeed Valve automatically moves to the in-line
position
