Presurization

Question 1

How is pressurization achieved?

Answer 1

By supplying constant inflow of air and by regulating the amount of air leaving aircraft through the Thrust Recovery Outflow Valve (TROV)

Question 2

Automatic pressurization is available down to what source of power?

Answer 2

Main batteries through static inverter

Question 3

What’s the meaning of amber FAULT light on CABIN PRESSURE CONTROL panel?

Answer 3

It indicates failure of both channels of dual channel controller: you’d have to select MANUAL

Question 4

When does pressurization system automatically switch to FLIGHT and begin to pre-pressurize cabin prior to takeoff?

Answer 4

It’s initiated if doors are closed and any of the following occur: switch is in FLIGHT position, airplane begins to move > 9 knots or throttles are advanced

Question 5

What happens in-flight when LANDING is selected on FLIGHTLANDING switch?

Answer 5

Cabin pressure control system automatically switches to descent pressurization schedule (i.e., 300 fpm).

Question 6

When does FLIGHT-LANDING switch automatically switch to LANDING?

Answer 6

When aircraft descends from cruise at least 1,000 feet

Question 7

When would you use semi-automatic (SEMI) mode?

Answer 7

Whenever FMS data is not available or is invalid, when directed by checklist, or at discretion of flight crew (e.g., flying in QFE environment or to high altitude airport)

Question 8

What’s one of the benefits of flying in SEMI mode?

Answer 8

in SEMI mode?

You have more control over the system

Question 9

What’s the purpose of MANUAL mode?

Answer 9

Used to manually control TROV and may be used as backup method in event of failure of both channels of cabin pressure controller.

Question 10

What moves the TROV in manual mode?

Answer 10

A DC motor controlled by the pilot with the knob on the CPCS

Question 11

In manual mode, how would you determine rate of TROV movement?

Answer 11

By observing motor power indicator: frequency of flashes is proportional to valve opening or closing speed.

Question 12

What’s the purpose of pressure relief valve?

Answer 12

It provides rate-limiting function to prevent damage to aircraft fuselage from excessive positive or negative pressures.

Question 13

What type of action does the pressurization system perform after landing to ensure minimal differential pressure exists within the cabin?

Answer 13

During ground operations when TROV is full open, pressure relief valve is forced open with bleed air (unless you’re in manual mode)

Question 14

When would pressure relief valve start to relieve pressure?

Answer 14

There are two (2) pneumatic chambers: one relieves at 10.80 differential pressure and the other relieves at 11.00

Question 15

What are cabin pressure low warning trip points based on?

Answer 15

Landing field elevation

Question 16

What are the prerequisites for Emergency Descent Mode (EDM)?

Answer 16

Cabin Pressure Low CAS message Aircraft altitude ≥ FL400 Autopilot engaged

Question 17

Describe aircraft operation in EDM

Answer 17

Aircraft automatically enters HDG hold mode, turns 90° left and enters FLCH mode with 340 kt manual speed (MAN SPD) target. Altitude preselector is set to 15,000 ft. If not already engaged, AT engages, and throttles pull back to facilitate rapid descent. The aircraft performs an ASEL capture at 15,000 ft and SPD target changes from 340 kts to 250 kts. The target SPD is maintained as long as AT is engaged.

Question 18

How can EDM be cancelled?

Answer 18

By disengaging AP

Question 19

With rapid loss of cabin pressure or altitude, what’s the first thing the crew should accomplish?

Answer 19

Don personal oxygen mask and ensure mask is set to 100% oxygen

Question 20

What is the air conditioner temperature range in NORMAL?

Answer 20

60 - 90

Question 21

What is the air conditioner temperature range in MANUAL?

Answer 21

35 - 230

Question 22

What do blue wing anti-ice lines indicate on ECS/PRESS synoptic page?

Answer 22

Wing anti-ice temperature is <=100 F within two minutes of activation.

Question 23

What do green wing anti-ice lines indicate on ECS/PRESS synoptic page?

Answer 23

Normal temperature (100 - 180 degrees F)

Question 24

What do amber wing anti-ice lines indicate on ECS/PRESS synoptic page?

Answer 24

Wing temp is <100 AFTER two minutes from the time it’s commanded to ON or > 180 F.

Question 25

What is the BAC minimum manifold set point range for operations at low power settings?

Answer 25

14 to 24 PSI

Question 26

Why are there set points for the BAC?

Answer 26

Set points exist to ensure adequate pneumatic temp and press at the various power settings and bleed air requirements.

Question 27

Can a BAC maintain 35 PSI without opening the high stage (8th) valve?

Answer 27

Yes.

If engine power is such that mid-stage air is enough to maintain 14, 24 or 35 PSI, then nothing happens. If not, the BAC opens the high stage valves.