Equipment Cooling

Question 1

What compartment does the equipment cooling provide air to

Answer 1

• Flight deck equipment
• Electrical and electronics racks (E&E)

Question 2

When is warm equipment cooling air ducted overboard on the ground

Answer 2

• Engines not operating
• Equipment cooling selector in NORM
• Ambient temperature moderate or high
  (Grnd exhaust valve open, inboard exhaust valve closed)

Question 3

WHen does the equipment cooling system configure for flight

Answer 3

When one or more engine on each wing is operating

Question 4

How can you manually configure the equipment cooling system for flight

Answer 4

Equipment Cooling Selector to STBY

Question 5

Which valve is closed when equipment cooling is in closed loop mode

Answer 5

Inboard exhaust valve

Question 6

What is the source of equipment cooling air for the flight deck

Answer 6

• two or three packs operating: flight deck equipment cooling source valve

Question 7

Describe. The operation of the equipment cooling system with the equipment cooling selector in OVRD

Answer 7

• Non-normal ops:
  + override in flight if fans inoperative OVRD
  + smoke/override valve opens, with all other valves closed, to overboard vent
  + pulls air though panel, equipment cooling ducts, E&E bay and out to create a reverse flow of air

Question 8

Under what conditions would the equipment cooling system revert to closed loop mode?

Answer 8

• LLCCAFR in FWD LOW, BOTH LOW, or FWD HIGH and temp ejected lower than 50F (10c)
  Or
• EQUIP COOLING switch in NORM or STBY with a single internal fan failure
  Or
• MAIN CARGO FIRE “ARM” switch ARMED