Pressurization

Question 1

How is the desired cabin pressure maintained normally?

Answer 1

The Cabin Pressure Control System (CPCS) regulates the outflow of air from the cabin by commanding the position of outflow valve. The CPCS has a preprogrammed schedule based on aircraft altitude and LFE.

Question 2

If the CPCS fails how can the crew manage cabin pressure?

Answer 2

Select CPCS mode MAN. Now crew is directly controlling position of outflow valve. Changes in thrust setting, alt, temp, or pressure will require crew to adjust valve.

Question 3

What is the purpose of the DITCH switch?

Answer 3

Will close outflow valve for water landing/close for deicing.

Question 4

What is the purpose of the DUMP switch?

What happens when pressed?

Answer 4

Notifies the AMSC to open the OFV and dump cabin pressure.

Cabin will climb to 14,900 at no more than 8000fpm. If below 14,500 it will fully depressurize cabin.

Question 5

What is the max cabin pressure differential permitted for all operations?

Answer 5

9.2 psid

Question 6

What is the max cabin diff for taxi, takeoff, and landing?

Answer 6

.2 psid

Question 7

What are the limitations regarding the baggage door in flight?

Answer 7

Must be closed for taxi, takeoff, and landing. Access to baggage is not permitted above 40k except by flight crew for emergency.

Question 8

What is the function of the safety outflow valve?

Answer 8

It is a pressure relief valve that in the event of a OFV failure it will limit the cabin diff to 9.45 psid.

Question 9

Single bleed service ceiling

Answer 9

FL260