Flight Deck
Since the flight deck requires only a fraction of the air supply provided by the left
pack, most of the left pack output is routed to the mix manifold.
Conditioned air for the flight deck branches into several risers which end at the
floor, ceiling and foot level outlets. Air diffusers on the floor under each seat
deliver continuous air flow as long as the manifold is pressurized.
Overhead diffusers are located on the flight deck ceiling, above and aft of the No.
3 windows. Each of these outlets can be opened or closed as desired by turning a
slotted adjusting screw.
There is also a dual purpose valve behind the rudder pedal of each pilot. These
valves provide air for warming the pilots' feet and for defogging the inside of the
No. 1 windshields. Each valve is controlled by knobs located on the Captain's and
First Officer's panels.
Passenger Cabin
The passenger cabin air supply distribution system consists of the mix manifold,
sidewall risers, and an overhead distribution duct.
Sidewall risers go up the right and left walls of the passenger cabin to supply air
to the overhead distribution duct. The overhead distribution duct routes
conditioned air to the passenger cabin. It extends from the forward to the aft end
of the ceiling along the airplane centerline and also supplies the sidewall diffusers.
Recirculation Fan
The recirculation fan system reduces the air conditioning system pack load and
the engine bleed air demand. Air from the passenger cabin and electrical
equipment bay is drawn to the forward cargo bay where it is filtered and
recirculated to the mix manifold. The fans are driven by AC motors. Each
recirculation fan operates only if the respective RECIRC FAN Switch is selected to
AUTO.
Since the flight deck requires only a fraction of the air supply provided by the left
pack, most of the left pack output is routed to the mix manifold.
Conditioned air for the flight deck branches into several risers which end at the
floor, ceiling and foot level outlets. Air diffusers on the floor under each seat
deliver continuous air flow as long as the manifold is pressurized.
Overhead diffusers are located on the flight deck ceiling, above and aft of the No.
3 windows. Each of these outlets can be opened or closed as desired by turning a
slotted adjusting screw.
There is also a dual purpose valve behind the rudder pedal of each pilot. These
valves provide air for warming the pilots' feet and for defogging the inside of the
No. 1 windshields. Each valve is controlled by knobs located on the Captain's and
First Officer's panels.
Passenger Cabin
The passenger cabin air supply distribution system consists of the mix manifold,
sidewall risers, and an overhead distribution duct.
Sidewall risers go up the right and left walls of the passenger cabin to supply air
to the overhead distribution duct. The overhead distribution duct routes
conditioned air to the passenger cabin. It extends from the forward to the aft end
of the ceiling along the airplane centerline and also supplies the sidewall diffusers.
Recirculation Fan
The recirculation fan system reduces the air conditioning system pack load and
the engine bleed air demand. Air from the passenger cabin and electrical
equipment bay is drawn to the forward cargo bay where it is filtered and
recirculated to the mix manifold. The fans are driven by AC motors. Each
recirculation fan operates only if the respective RECIRC FAN Switch is selected to
AUTO.
