Pressurization and Air Conditioning

Question 1

How many caban pressurization modes does the CRJ-200 have?

Answer 1

8

Question 2

Ground Mode

Answer 2

Both outflow valves open.

Question 3

PRE-PRESSURE MODE:

Answer 3

When thrust levers are advanced the cabin goes to -150 AGL at 300 FPM.

Question 4

TAKE OFF ABORT MODE:

Answer 4

FTM VOL 2 Air Conditioning and Pressurization

1. When thrust levers retarded to idle the cabin climbs at 500 FPM for 20 sec then returns to ground mode.

Question 5

CLIMB MODE

Answer 5

FTM VOL 2 Air Conditioning and Pressurization Page 34

1. Cabin climbs at 500fpm

Question 6

FLIGHT ABORT MODE

Answer 6

FTM VOL 2 Air Conditioning and Pressurization Page 34

1. This mode is armed whe the cabin is at less then 6000 feet AGL for 10 min after weight off wheels. When a 1,000 FPM decent is initiated the cabin preselect is reset to the departure field elevation.

Question 7

CRUISE MODE

Answer 7

FTM VOL 2 Air Conditioning and Pressurization Page 34

1. When airplane altitude is maintained (+ 200 feet) for 10 minutes, a descent schedule occurs. When descent is initiated, the cabin descends at 300 FPM.

Question 8

LANDING MODE

Answer 8

Cabin altitude is driven below field elevation. When cabin is below landing elevation, the cabin will climb at 500 FPM for 60 seconds then the outflow valves are driven full open.

Question 9

TOUCH AND GO MODE

Answer 9

FTM VOL 2 Air Conditioning and Pressurization Page 34

1. On touchdown, the system assumes landing mode; when thrust levers advance it goes into pre-pressure mode.

Question 10

How many Pack does the CL-65 have?

Answer 10

2

Question 11

What does pressing the EMER DEPRESS switch light do?

Answer 11

FTM VOL 2 Air Conditioning and Pressurization Page 33​

1. Commands both outflow valves to full open
2. The altitude limiters will attempt to prevent the cabin from climbing above 14,250 + 750 feet

Question 12

What does the Amber FAULT light on the PRESS CONTROL switch light mean?

Answer 12

The FAULT (amber) light illuminates when both pressure controllers have failed.

Question 13

What does the MAN RATE knob do?

Answer 13

FTM VOL 2 Air Conditioning and Pressurization Page 33​

1. The MAN RATE selector range is from 50 - 3,000 + 1,000 FPM and will be displayed on the ECS Synoptic page.

Question 14

The outflow valves are electrically controlled and
slaved through a pneumatic line. How are they operated in Auto Mode?

What about Manual mode?

Answer 14

FTM VOL 2 Air Conditioning and Pressurization Page 32

In Auto mode the left valve is the master,
• the right is slaved, and
• the valves respond to electric inputs.

In Manual Mode:
• the right valve is the master, and
• the valves respond to pneumatic inputs.

Question 15

How many pressure controllers does the CRJ-200 have?

Answer 15

2

One is always in use while the other acts as a back up. If one fails it auto switches to the back up.

ADC 1 is the normal input and ADC 2 is the back up. If both pressure controllers fails they system goes into hold mode.

Controlers auto switch when on the ground after 3 min

Question 16

What altitude due altitude limit controlers keep the cabin alt at?

Answer 16

Altitude limit controllers will close to limit cabin altitude to 14,250 + 750 feet.

Question 17

When will the CPAM trigger the passenger oxygen masks to auto deploy?

Answer 17

The Cabin Pressure Acquisition Module (CPAM) will trigger the passenger oxygen auto-deploy system when cabin altitude reaches 14,000 feet. The CPAM will also turn on the no smoking and fasten seatbelt signs at 10,000 feet cabin altitude, if the PAX signs are selected to auto.

Question 18

When do you get the CABIN ALT caution message?

CABIN ATL warning message?

Answer 18

CAUTION: Cabin Alt 8,500.
WARNING: Cabin Alt 10,000 or greater

Question 19

What stages of bleed air do we have have on the CRJ-200 and what do they do?

Answer 19

• 7th Stage- Used for pressurizing some seals and gaskets.
• 10th Stage- Used for engine starts, air conditioning, equipment cooling, and pressurization.
• 14th Stage- Thrust reversers, wing and cowl anti-icing

Question 20

What sources do we have for 10th stage bleed air?

Answer 20

Normal is the 10 stage of the engine compressors but can also be supplied by the APU or a ground power cart.

Question 21

Why are the 10th Stsge bleed air valves interconnected?

Answer 21

• This prevents the airflow from the engines back flowing THROUGH the APU LCV into the APU causing damage to the APU compressor
• With Engines and APU running if the L/R 10th stage bleed is opened the APU LCV will close

Question 22

What purpose does the ISOL valve serve?

Answer 22

• Isolated the left from the right side of the 10th stage bleed manifold.
• Allows for crossover engine starts (known as Cross Bleed engine starts)
• APU Engine starts
• Ground air supply engine starts
• Crossover air conditioning

Question 23

What kind of leak detection do we have for 10/14th stage bleed air?

Answer 23

• Dual Loop for 10th Stage ( more than one source of bleed air more than one loop)
• single Loop for 14th Stage. ( one source one loop)

Question 24

What does the DUCT MON loop A/B test do?

Answer 24

It tests the continuity of the individual 10th stage loops A and B to ensure they are not shorted to ground.

Note that if “1” of the loops had a short it can be placed on MEL. Not both.

Question 25

How is pack pressure and out put divided through out the CRJ-200?

Answer 25

* Right Pack- 70% cabin and 30% to distribution manifold. Cabin exhaust air is routed under the floor boards to the out flow valves. * Left Pack -70% flight compartment and 30% to distribution manifold. Flight compartment exhaust air is routed through the avionics bay to the out flow valves.

Question 26

What pressure does the 10th stage system regulate the packs to? Single pack OPPS?

Answer 26

30PSI for dual packs 41PSI for single pack

Question 27

The cargo fan supplies what kinda of air to the cargo compartment?

Answer 27

Re-circulated cabin exhaust air Note- if the temperate exceeds 35^c the fan shuts down and a yellow caution message on ED2 is displayed.

Question 28

How are the Out Fow Valves operated?

Answer 28

Out Flow Valves are operated by a jet pump driven by the 10th Stage air. * Auto Mode- left valve is master and right is slave and both respond to electronic inputs. * Manual Mode- right is master and valves respond to pneumatic imputes.

Question 29

With the PAX signs in “AUTO”. When will the seatbelt and no smoking signs automatically turn on

Answer 29

CPAM will turn on the PAX signs at 10,000 feet if the switch is in auto.

Question 30

If the cabin depressurizes or if the PACKS are left off, at what cabin altitude will the oxogen masks auto deploy?

Answer 30

14,000 feet.

Question 31

What does the “FAULT” light illuminated on the cabin press panel mean?

Answer 31

It will illuminate only when both cabin pressure controllers have failed.

Question 32

What happens when the guarded EMER DEPRESS switch light is selected?

Answer 32

Both outflow valves open to depressurize the cabin. The altitude limiters will attemptn prevent the cabin from rising above 14,250 +\- 750 feet.

Question 33

How does the MAN ALT switch work?

Answer 33

In the UP position it allows the outflow valves to open and cabin ALT to climb at the rate selected by the MAN RATE knob In the DOWN position it allows the outflow valves to close and the cabin alt to descend at a rate selected by the MAN RATE knob. The man rate knob range is 50-3,000 +/- 1,000 fpm.

Question 34

When do Presurization controlers switch?

Answer 34

Automaticly in flight if one fails or After 3 min after weight on wheels.

Question 35

When do we get a BLEED MISCONFIG caution messege

Answer 35

1. When the Wing or Cowl anti-ice are selected ON 2. 10th Stage SOV open 3. Landing gear down or Flaps greater then 0

Question 36

What system cools our avionics

Answer 36

The cockpit avionics and avionics bay are coold by the conditioned air from the cockpit supplie or recirculated air from the cabin and cockpit.

Question 37

What is the split in the packs from cabin to cockpit

Answer 37

**LEFT PACK** 70% cockpit 30% cabin **RIGHT PACK** 30%cockpit 70% cabin

Question 38

What does the FAULT light on the L or R pack switch light mean?

Answer 38

When the pack senses over presure of over temp. The pack will automaticly shut down and the FAULT light will tun on for the individual pack.

Question 39

What does the RAM AIR function do for the aircraft

Answer 39

1. Cooles Hydraulic systems 1 & 2 2. Provides pack heat exchanger cooling. 3. Ventalates the cabin and cockpit during total presureazation failure.