DOC AIRBUS | AMM A320FAIRFOIL - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
1. General
The wings are the only airfoil sections to be protected against icing conditions. The leading edge slats 3, 4 and 5 are thermally anti-iced by a manually selected hot air system which directs engine bleed air into the leading edges of the slats.
Air for ice protection is supplied by the pneumatic system, the flow being controlled by a pressure control/shut-off valve. The pneumatically powered control/shut-off valves are selected open when power is supplied to the electrical circuit. Airflow trimming restrictors are fitted downstream of each valve.
The air leaving the control valves passes through ducts in the wing fixed leading edge to a telescopic duct which routes the air to the inboard end of the piccolo duct in slat 3. Air is distributed along slats 3, 4 and 5 by piccolo ducts interconnected by flexible couplings.
The piccolo ducts release the air into the slats through holes along their forward length. The air flows around the forward area of the slat then goes through acceleration slots into the rear section. It is then released overboard through the holes in the bottom surface of the slat.
When only one engine is available to supply hot air, the pneumatic system crossfeed duct is used to supply the two wings from one engine.
The wing-ice protection system can only be operated continuously while the aircraft is flying, but can be tested on the ground for a limited period.
Airfoil Anti-icingThe wings are the only airfoil sections to be protected against icing conditions. The leading edge slats 3, 4 and 5 are thermally anti-iced by a manually selected hot air system which directs engine bleed air into the leading edges of the slats.
Air for ice protection is supplied by the pneumatic system, the flow being controlled by a pressure control/shut-off valve. The pneumatically powered control/shut-off valves are selected open when power is supplied to the electrical circuit. Airflow trimming restrictors are fitted downstream of each valve.
The air leaving the control valves passes through ducts in the wing fixed leading edge to a telescopic duct which routes the air to the inboard end of the piccolo duct in slat 3. Air is distributed along slats 3, 4 and 5 by piccolo ducts interconnected by flexible couplings.
The piccolo ducts release the air into the slats through holes along their forward length. The air flows around the forward area of the slat then goes through acceleration slots into the rear section. It is then released overboard through the holes in the bottom surface of the slat.
When only one engine is available to supply hot air, the pneumatic system crossfeed duct is used to supply the two wings from one engine.
The wing-ice protection system can only be operated continuously while the aircraft is flying, but can be tested on the ground for a limited period.