Podcast
Questions and Answers
At what pressure do the safety valves open?
At what pressure do the safety valves open?
What information is used to optimize cabin pressurization in automatic mode?
What information is used to optimize cabin pressurization in automatic mode?
How does the avionics ventilation system control temperature with skin temperature below +35°C?
How does the avionics ventilation system control temperature with skin temperature below +35°C?
When does the emer.ram air inlet valve open when the Ram Air pb is set to 'ON'?
When does the emer.ram air inlet valve open when the Ram Air pb is set to 'ON'?
Signup and view all the answers
When does the RPCU automatically open the outflow valve?
When does the RPCU automatically open the outflow valve?
Signup and view all the answers
What happens to the outflow valve when the RAM AIR pb is set to 'ON'?
What happens to the outflow valve when the RAM AIR pb is set to 'ON'?
Signup and view all the answers
What is the primary function of the safety valves?
What is the primary function of the safety valves?
Signup and view all the answers
What is the condition for the emer.ram air inlet valve to open?
What is the condition for the emer.ram air inlet valve to open?
Signup and view all the answers
What is the purpose of the RPCU?
What is the purpose of the RPCU?
Signup and view all the answers
What happens when the RPCU automatically opens the outflow valve?
What happens when the RPCU automatically opens the outflow valve?
Signup and view all the answers
Study Notes
Cabin Air System Overview
- The Mixer Unit connects to cabin fans, LP ground connector, emergency ram air inlet, and Pack 1 and Pack 2.
- Trim air valves optimize temperature by adding fresh air.
Temperature Regulation and Control
- Hot air pressure regulating valve failure causes:
- Optimized regulation loss.
- Temperature remains at the selected value when the failure occurs.
- Hot air pressure regulating valve is controlled by the Air Conditioning System Controllers.
- Temperature control is automatic through the Air Conditioning System Controllers and pack controllers.
Pack Functionality
- Bleed air from the APU with the APU bleed valve open automatically selects pack flow to normal.
- The pack flow control valve is pneumatically operated and electrically controlled.
- Pack flow may be selected from both the cockpit overhead panel and cabin stations.
Cabin Pressure and Altitude Control
- Maximum normative cabin altitude is approximately 9,550 ft ± 350 ft.
- Maximum negative differential pressure for the cabin is -2 psi.
- Safety valves prevent excessive positive and negative pressure differential.
- Cabin pressurization begins at engine start, optimizing during ascent and cruise.
Operation Conditions and Failures
- Emergency ram air inlet valve opens based on delta P conditions and Ditching push button settings.
- If trim air valve fails, optimized temperature regulation of the corresponding zone is lost.
- The hot air pressure regulating valve closes with duct overheat or pack overheat.
Operational Limits
- During landing, packs ram air inlet flaps open when speed is below 70 knots after a delay.
- Maximum cabin altitude warning occurs when cabin altitude exceeds 14,000 ft.
- The outflow valve indicator can show amber if the valve is fully closed or open excessively.
- Use of Packs alongside LP ground unit is prohibited on hot airfields over specified temperatures.
Safety and Emergency Protocols
- The Residual Pressure Control Unit (RPCU) automatically manages outflow valve operations during abnormal pressure conditions.
- Under SYS 1 fault, the system transitions to SYS 2, which may require crew action depending on the circumstances.
- The safety valves are operated pneumatically.
Miscellaneous
- Conditioned air is distributed throughout the cockpit, cargo bays, and cabin, with ventilation provided by galleys and lavatory fans.
- Cabin altitude adjustments are based on automatic inputs from FMGC, ADIRS, and environmental readings.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge of aircraft air systems, including the mixer unit, hot air pressure regulating valves, and bleed air supply from the APU. This quiz covers various aspects of air systems in aviation.
