21-20 Pressurisation

Question 1

What is the maximum positive differential pressure of the aircraft?

Answer 1

9.0psi

Question 2

What is the maximum negative differential pressure of the aircraft?

Answer 2

-1.0psi

Question 3

What is the safety relief valve setting?

Answer 3

8.6psi

Question 4

Cabin altitude warning at?

Answer 4

9550ft

Question 5

Maximum normal cabin altitude?

Answer 5

8000ft

Question 6

What does CPC stand for? How many are there?

Answer 6

Cabin Pressure Controller (x2)

Question 7

When does a transfer of CPC take place?

Answer 7

70 seconds after landing or when one fails

Question 8

What information does the CPC use from the FMGC?

Answer 8

Landing elevation and landing QNH

Question 9

What information does the CPC use from the ADIRS?

Answer 9

Pressure altitude

Question 10

In automatic pressure control mode, how many phases of flight are there? What are they?

Answer 10

6

GROUND (GN): Outflow valve fully open
TAKEOFF (TO): Pre-pressurises to difference of +0.1 psi
CLIMB (CL): Uses aircraft climb rate
CRUISE (CR): Maximum 8000ft cabin altitude
DESCENT (DE): Maximum cabin rate of -750ft/m, and pressurises aircraft to landing field pressure + 0.1psi
ABORT (AB): No climb after takeoff? Cabin pressure set back to +0.1psi

FCOM 21-20-30

Question 11

What pre-pressurisation rate does the CPC use on the ground?

Answer 11

-400fpm to deltaP of +0.1psi

Question 12

What de-pressurisation rate does the CPC use on the ground?

Answer 12

+500fpm to deltaP of +0.1psi

Question 13

For how long must you leave the cabin pressure MODE SEL in MAN before returning it to AUTO to force a transfer to the other system?

Answer 13

At least 10 seconds

FCOM 21-20-40