AMS: Pressurization

Question 1

Where are the Outflow Valves (OFV), Pressure Relief Valves (PRV) and Negative Pressure Relief Valves (NPRV) located?

Answer 1

Aft Cabin pressure bulkhead

Question 2

Describe the Control, Activation, and Fail Position or the following valves:

OFV (Outflow Valve)
PRV (Pressure Relief Valve)
NPRV (Negative Pressure Relief Valve)

Answer 2

1) OFV is electrically controlled and activated and fails last

2) PRV and NPRV are mechanically controlled and activated (DeltaP) and fail CLOSED.

Question 3

Where is the cockpit indication of the Outflow Valve Position

Answer 3

Environmental Synoptic Page

Question 4

What is the primary difference between the two pressurization Electric Control and Monitoring Unit (ECMU) channels?

Answer 4

1) One Channel controls the outflow valve automatically
2) The other channel controls the outflow valve manually through the MAN position of the PRESN MODE switch

Question 5

Doe both pressurization ECMU channels (controlling AUTO and MAN) provide Cabin Altitude Limit Protection

Answer 5

Yes

Question 6

What actions occur when the PRESN DUMP button is pushed?

Answer 6

1) Outflow valve Opens
2) Recirculating/ Evaporator fans are disables

Question 7

What is the maximum cabin altitude allowed by each pressurization ECMU channel, including a situation where the PRESN DUMP button is pushed

Answer 7

AUTO: 12,000 FT
MAN: 14,500 FT

Question 8

Under what conditions does the red CAB ALTITUDE HI (CAS) illuminate when the aircraft altitude is below 25,000ft

Answer 8

1) When LFE less than 8300 and Cabin Altitude is at 10,000ft
2) When LFE is 8300 to 9600 and Cabin Altitude is at 11,500ft
3) When LFE is greater than 9600 and Cabin Altitude is 14,200ft

Question 9

Under what conditions does the red CAB ALTITUDE HI (CAS) illuminate with the aircraft altitude above 25,000

Answer 9

Cabin Altitude greater than 10,000ft