AIR SYSTEMS

Question 1

High Flow Schedule

Answer 1

• On the ground, when only the APU or external air source is supplying pneumatic air (both packs)
• If one pack is inoperative
• If associated recirculation fan is off or inoperative

High flow to the opposite pack is inhibited when the RPM of either engine falls below a preset value.
Limit EPR/N1 for the associated engine is automatically reduced when a pack is operating in high flow.
(767) High flow to the opposite pack is inhibited when:
Wing anti-ice is on and only one engine is supplying bleed air N2 RPM of either engine is below a preset value
Flaps are not up
(763) AFT cargo fire arm switch is pushed

Question 2

High Flow
( Inhibited )

Answer 2

• RPM of either engine falls below a preset value.
• Limit EPR/N1 for the associated engine is automatically reduced when a pack is operating in high flow.
  (767) High flow to the opposite pack is inhibited when:

Wing anti-ice is on and only one engine is supplying bleed air 
N2 RPM of either engine is below a preset value
Flaps are not up
(763) AFT cargo fire arm switch is pushed