Pneumatics Flashcards
When the HP valve is closed with both engines running (i.e. normal system pressure) what bleed air delivery pressure is maintained?
Where is the pressure displayed?
Bleed air delivery pressure is maintained at 45 +/-5 PSI at the precooler inlet
Pressure is displayed on the ECAM Bleed page
Where is bleed air temperature regulated?
By a precooler which uses cooling bleed air from the engine fan.
What warnings are lost following a failure of BMC 1?
Remaining BMC (Bleed Monitoring Computer 2) does not provide:
Eng 1 bleed leak
APU bleed leak
The precooler outlet temperature on the ECAM Bleed page is normally displayed in green, what conditions must exist for it to be displayed in amber?
Temp will be displayed in amber if the BMC detects an overheat or low temperature.
Low temp only detected in flight with wing anti ice on and prv open (150°C)
When are ANTI ICE indications (in white) displayed on the ECAM Bleed page?
The ANTI ICE indications are displayed on the ECAM Bleed page as soon as the Wing Anti Ice pb has been selected ON.
If the X-Bleed selector sw is set to AUTO (except during engine start) what will happen automatically following a left wing pneumatic leak?
The crossbleed valve will close automatically
The pre-cooler cools air to what temp?
200° C
Air to air precooler
The BMC will always detect and indicate overheat, under what conditions will it detect low temp?
In flight
Wing anti-ice on
Pressure regulating valve is open
Following a failure of one BMC, what warnings are still available from the remaining BMC?
Over pressure
Over temp
Wing leak
How many BMCs are there?
2 Bleed Management Computers
What warnings are lost following a failure of BMC 2?
Eng 2 bleed leak
What are the 3 sources of high pressure for the pneumatic system?
Engine bleed systems
APU load compressor
HP ground connection
What are the consequences of a Bleed Management Computer failure?
The adjacent BMC provides most monitoring functions
Associated FAULT light lost
Associated bleed valve does not close automatically
With the X-BLEED switch in AUTO, when will the cross bleed valve close?
If the APU bleed valve is closed
Wing leak
Pylon leak
APU leak (except during engine start)
Where is bleed air pressure and temp measured?
Pressure measured at precooler inlet
Temperature measured at precooler outlet
The precooler inlet pressure is normally displayed in green when does it display amber?
If < 4PSI or overpressure
