Pressurization

Question 1

What does the pressurization system consist of?

Answer 1

• Two Air Supply Cabin Pressure Controllers
• Remote pressure sensor

Question 2

Which ASCPC is the master?

Answer 2

• The left ASCPC

Note: The right automatically assumes control should the left one fail

Question 3

How many outflow valves are installed on the B777?

Answer 3

• Two

20% of the air exits through the FORWARD outflow valve

80% of the air exits through the AFT outflow valve

This configuration improves smoke removal and ventilation

Question 4

How is excess pressure relieved?

Answer 4

• Through two installed positive pressure relief valves

Question 5

How many negative pressure relief valves are installed on the B777?

Answer 5

Four

Two on each side of the forward fuselage

Question 6

What modes does the cabin altitude controller operate in?

Answer 6

• Climb mode
• cruise mode
• descent mode

Question 7

In cabin altitude controller cruise mode, what is the maximum cabin altitude?

Answer 7

• 8000 ft

Question 8

When does the the cabin altitude controllers enter the descent mode?

Answer 8

At TOD, or at initial descent of 1000 ft from cruise altitude

Question 9

When does the EICAS caution message CABIN ALTITUDE display?

Answer 9

When the cabin altitude climbs above 8500 ft

Question 10

When does the EICAS display the warning message CABIN ALTITUDE?

Answer 10

If the cabin altitude climbs above 10,000 ft