Bleed Air System Flashcards
The bleed air system receives air from 3 main sources, they are ?
- Engines
- APU
- Ground pneumatic sources
What (7) components & systems use bleed air?
- Air driven hydraulic pumps
- Wing anti ice
- Cargo heating
- Engine & APU starting
- Air conditioning packs
- Hydraulic reservoir pressurisation
- Trim air
Uses of APU bleed air on the ground?
- Air conditioning &,
- Engine starting
APU bleed air can be used in flight up to approx ?
22,000 ft
Positioning the APU bleed air switch to AUTO with the APU running opens which valves?
The APU bleed air valve & all 3 isolation valves (allowing air into the bleed air ducting)
Bleed air from the engine comes from the ……………section?
Low pressure or LP section
Air from the LP section is used primarily during ?
High thrust settings such as t/o, climb & cruise
Bleed air from the HP section is used to ?
Supplement LP air during low thrust settings such as descent
The bleed air system is controlled by the ?
ASCPC - the air supply & cabin pressure controller
What’s the job of the ASCPC?
To open & close the HP valve, & adjust the Fan Air Modulating Valve to provide cold air for the pre-cooler, which controls the bleed air temperature in the ducts
What does the PRSOV do?
The pressure regulating valve (PRSOV), controls the flow & pressure of air to the ducts
If the fan air pre-cooler cannot provide enough cooling for the bleed air, the PRSOV ?
Reduces the quantity of bleed air to keep the temperature within limits
Bleed Air Duct Protected Areas
Engine struts
Left wing
Right wing
Body duct
Under normal circumstances, what is the source of bleed air to start the second engine?
APU
What best describes the leak detection & isolation operation?
Automatic leak detection & automatic isolation, crew action is not required
