Pressurization Flashcards
Each cabin pressurization controller directly controls a ___________ to independently operate the outflow valve.
DC Powered Motor
T/F: One pressurization controller is alternately sequenced as the primary operational controller for each new flight?
True
The amber pressurization AUTO FAIL light will illuminate for what conditions?
Indicates a single controller failure when ALTN light is also illuminated.
Indicates a dual controller failure when illuminated alone
When does the cabin altitude warning horn sound?
When the cabin altitude exceeds 10,000 feet
At FL410, the cabin altitude should be…
8,000 feet or 8.35 psi
T/F: The manual pressurization controller has a separate DC powered motor that operates the outflow valve
True (separate from the motors the primary, automatic pressurization controllers use)
Where is the aft outflow valve located?
The valve is mounted on the right underside of the airplane immediately aft of the aft cargo compartment.
How long does it take the outflow valve to travel from fully open to fully closed?
Up to 20 seconds
When do the positive pressure relief valves (2) open ?
8.95 psi differential
What is the maximum cabin pressure differential?
9.1 psi
Where is the negative pressure relief valve located?
The negative pressure relief valve is on the lower aft fuselage, on the right side, near the aft service door
What is the maximum pressure differential for takeoff?
0.125 psi
When does the OFF SCHED DESCENT light illuminate?
The OFF SCHED DESCENT light will illuminate when the airplane descended before reaching the planned cruise altitude set in the FLT ALT indicator.
What is the max differential pressure for landing?
0.125 psi
T/F: The cabin is set to land slightly pressurized so that rapid changes in altitude during approach result in minimum cabin pressure changes
True
The majority of the Passenger cabin air is circulated through the air return grills and ducting of the _____________, then is discharged overboard via the aft outflow valve.
AFT cargo compartments
How many positive pressure relief valves does the aircraft have?
2
Normal operating differential pressure is allowed or not allowed within the amber band of the differential pressure gauge?
Allowed
The ______________ valve prevents ambient pressure from exceeding cabin pressure by an excessive amount
negative pressure relief
Where are the two main pressurization controllers located?
E&E Compartment
When does the ALTN light illuminate at the bottom of the Bleed Air Control Panel?
- Pressurization mode selector in ALTN position, or
- If both ALTN and AUTO FAIL lights are lit, a single controller has failed and the has auto transferred to the other controller (when in Auto mode ) `
During automatic pressurization, the cabin climbs at a rate ___________ to the aircraft rate of climb.
proportional
When does the OFF SCHED DESCENT light illuminate?
When the airplane descended before reaching the planned cruise altitude set in the FLT ALT indicator.
T/F: The cabin is set to land slightly pressurized so that rapid changes in altitude during approach result in minimum cabin pressure changes.
True
