Pressurization Flashcards
How does the aircraft meter pressure in the aircraft
Let air out of the outflow valves
How many outflow valves are there
Two
Pneumatic
Electro-pneumatic
What valve is slaved to which one
Pneumatic to electro-pneumatic
Which valve is being used in manual mode
Peumatic
When does the cabin presurize
It pressurizes to 300 ft below field elevation on takeoff roll
What is the max negative pressure differential
-0.03 PSI
When does the cabin altitude light turns ON
10,000 ft cabin altitude
What is the cabin pressure limiter does
Limits cabin altitude to 13,000 +- 1,500 ft
When does the cabin pressure begins to climb on TO
15 seconds after the gear is up
What cabin altitude we set when descending
300 ft below field elevation
What altitude do we set the cabin to prior to the flight
1,000 ft above cruise
How fast does the cabin climb or descend while the rate knob is in detent
650fpm up
45fpm down
What happens when the cabin is dumped
Rapidly decompresses cabin to 13,000 ft
Max differential prssure
7.2 PSI
Normal differential pressure
7.0 PSI
What happens to pressurization if you loose both main generators
Engine bleeds will fail close so no more pressurization available. The cabin will slowly leak
Is cabin limiter available in MAN mode
No it bypasses altitude limiter
How to evacuate smoke from the cabin other then DUMP
Use manual mode to depressurize the cabin. Move the manual controller form 1 o’clock position to the right to raise the cabin altitude thus remove the smoke form the cabin
What should you consider when evacuation the aircraft after landing
DUMP the cabin on the on the approach so you don’t have to wait for the aircraft to depressurize
Airplane is pressurized by means of
Conditioned air form air conditioning system
Pressurization is controlled in
Automatic mode and Manual mode
Which compartment is not pressurized
Avionics bay
How many outflow valves control air discharge
Two
In AUTO mode which valve operational
Pneumatic and Electro-pneumatic
In manual mode which valves are operational
Only pneumatic
With the engines and electrical system off
Both valves are closed
The cabin climb rate may be set between
200-1,450 fpm
The cabin descend rate may be set between
150-1,000 fpm
On the ground engines are running and electrical system is on
Both vales are open
Manual controller rate
UP 2,500 fpm
DN -1,500 fpm
DUMP mode
Depressurizes at 14,400 fpm to 13,000 ft
The AUTO mode of setting the pressurization is always used unless
There is an electrical failure
The AUPO system fails
