DOC AIRBUS | AMM A320FENGINE AIR INTAKE ICE PROTECTION - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
1. General
The ice protection system of the engine air intakes is normally selected only in icing conditions.
Ice protection heats the intake cowls with air bled from the engine compressor.
The function of the ice protection of the engine air intakes is to supply bleed air to heat the inlet lip during icing encounters. This maintains the inlet duct of the engine free of harmful accumulation of ice.
The installation consists of ducting, coupling, seals, a shutoff valve, mechanical supports and a piccolo tube.
The air bled from the seventh stage of the high compressor is the heat source.
A solenoid-operated shutoff valve (which is designed to be spring-loaded in the closed position in case of failure) provides the on-off control. The piccolo tube distributes the air within the leading edge of the intake cowl. The spent air exhausts via a flush duct in the aft cavity of the intake cowl.
** ON A/C NOT FOR ALL The ice protection system of the engine air intakes is normally selected only in icing conditions.
Ice protection heats the intake cowls with air bled from the engine compressor.
The function of the ice protection of the engine air intakes is to supply bleed air to heat the inlet lip during icing encounters. This maintains the inlet duct of the engine free of harmful accumulation of ice.
The installation consists of ducting, coupling, seals, a shutoff valve, mechanical supports and a piccolo tube.
The air bled from the seventh stage of the high compressor is the heat source.
A solenoid-operated shutoff valve (which is designed to be spring-loaded in the closed position in case of failure) provides the on-off control. The piccolo tube distributes the air within the leading edge of the intake cowl. The spent air exhausts via a flush duct in the aft cavity of the intake cowl.
2. Component Location
Ice Protection of the Engine Air Intakes - Indications on Upper ECAM Display Unit ** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL Ice Protection of the Engine Air Intakes - Indications on Upper ECAM Display Unit ** ON A/C NOT FOR ALL | FIN | FUNCTIONAL DESIGNATION | PANEL | ZONE | ACCESS DOOR | ATA REF |
|---|---|---|---|---|---|
| ** ON A/C NOT FOR ALL | |||||
| 2DN1 | P/BSW-ANTI ICE/ENG 1 | 25VU | 210 | 30-21-00 | |
| 2DN2 | P/BSW-ANTI ICE/ENG 2 | 25VU | 210 | 30-21-00 | |
| 4000DN | VALVE-ENG AIR INTAKE ANTI ICE | 410 | 30-21-51 | ||
** ON A/C NOT FOR ALL
4. Power Supply
The electrical supply and protection of the components is as follows:
** ON A/C NOT FOR ALL The electrical supply and protection of the components is as follows:
| ------------------------------------------------------------------------------ |
| ! COMPONENT/FUNCTION ! CIRCUIT BREAKER ! BUSBAR ! |
| !----------------------------------!-------------------------!---------------! |
| ! ANTI ICE/ENG 1 pushbutton switch ! ! ! |
| ! FAULT legend ! ! ! |
| ! ON legend ! 1DN1 ! 101PP ! |
| ! ENG 1 air intake ! ! ! |
| ! anti ice valve ! ! ! |
| !----------------------------------!-------------------------!---------------! |
| ! ANTI ICE/ENG 2 pushbutton switch ! ! ! |
| ! FAULT legend ! ! ! |
| ! ON legend ! 1DN2 ! 202PP ! |
| ! ENG 2 air intake ! ! ! |
| ! anti ice valve ! ! ! |
| ------------------------------------------------------------------------------ |
5. Interface
A. Interface with the Engine Interface Unit (EIU)
- The information (ANTI ICE pushbutton switch configuration) is sent to the EIU which transmits it to the Full Authority Digital Engine Control (FADEC) by an ARINC 429 bus (label 032 bit 22). The FADEC uses this bit to select the continuous ignition.
- Oil low press and ground information is used to avoid an unwanted anti ice fault on ground, engine not running (anti ice valve open without motive pressure).
B. Interface with the Air Conditioning System Controller (ACSC)
The configuration of the ANTI ICE pushbutton switch or position of the anti ice valve are used for computation of the air bleed status.
The configuration of the ANTI ICE pushbutton switch or position of the anti ice valve are used for computation of the air bleed status.
C. Interface with the System Data Acquisition Concentrator (SDAC)
A warning message is generated on the ECAM system in case of disagreement between anti ice valve control and position.
A warning message is generated on the ECAM system in case of disagreement between anti ice valve control and position.
6. Component Description
[4000DN]
The anti-ice valve is a butterfly shutoff valve of the on/off type. The valve is spring-loaded to the closed position in the absence of motive pressure. A solenoid controls closure of the valve. The valve is fully open in the event of electrical signal loss and with sufficient motive pressure. The valve operates when the upstream motive pressure is greater than 7 psig.
Upon energization to the solenoid, the valve closes.
The solenoid plunger retracts and causes:
De-energization of the solenoid opens the valve. The solenoid plunger extends under the action of the plunger spring. This drives the pilot ball against the motive pressure seat of the pilot and vents chamber A to ambient.
The motive pressure in chamber B acts on the piston to:
Without application of motive pressure, it is possible to move the valve to the desired position by application of a torque of not more than 13 lbf.in (0.15 m.daN) to a standard hexagonal nut attached to the butterfly shaft.
Insertion of the locking pin through the locking hole on the valve body into the mating hole in the piston locks the valve. A ball detent mechanism in the end of the locking pin retains the pin in the hole corresponding to the desired valve position.
A visual position indicator shows the position of the valve.
A visual pop-out overpressure indicator comes out in case of overpressure.
Two hermetically sealed switches actuated by a cam give the electrical position indication.
The cam is splined to the shaft of the actuator. The switches are capable of operation in a high temperature environment. The switches are configured to give a disagreement indication signal if the valve is not in the commanded position.
** ON A/C NOT FOR ALL [4000DN]
The anti-ice valve is a butterfly shutoff valve of the on/off type. The valve is spring-loaded to the closed position in the absence of motive pressure. A solenoid controls closure of the valve. The valve is fully open in the event of electrical signal loss and with sufficient motive pressure. The valve operates when the upstream motive pressure is greater than 7 psig.
Upon energization to the solenoid, the valve closes.
The solenoid plunger retracts and causes:
- the motive pressure to push the pilot ball against the pilot vent seat,
- the motive pressure to flow to chamber A.
De-energization of the solenoid opens the valve. The solenoid plunger extends under the action of the plunger spring. This drives the pilot ball against the motive pressure seat of the pilot and vents chamber A to ambient.
The motive pressure in chamber B acts on the piston to:
- overcome the spring,
- drive the valve to the fully open position.
Without application of motive pressure, it is possible to move the valve to the desired position by application of a torque of not more than 13 lbf.in (0.15 m.daN) to a standard hexagonal nut attached to the butterfly shaft.
Insertion of the locking pin through the locking hole on the valve body into the mating hole in the piston locks the valve. A ball detent mechanism in the end of the locking pin retains the pin in the hole corresponding to the desired valve position.
A visual position indicator shows the position of the valve.
A visual pop-out overpressure indicator comes out in case of overpressure.
Two hermetically sealed switches actuated by a cam give the electrical position indication.
The cam is splined to the shaft of the actuator. The switches are capable of operation in a high temperature environment. The switches are configured to give a disagreement indication signal if the valve is not in the commanded position.
7. Operation/Control and Indicating
A. General
The air bled from the seventh stage of the HP compressor passes through four duct sections and line-mounted valve of the on-off type. At the forward bulkhead of the intake cowl, the anti-ice system interfaces with the piccolo tube in the intake lip. The spent air then exhausts overboard via the exhaust sleeve/flush duct assembly.
The airflow pressure is controlled by an anti ice valve which is of the butterfly type and electrically operated. The safety position of the valve is fully open.
The flow factor is:
ff = QxSQR(T5)/P5
T5 = absolute total temperature (in deg. K)
P5 = absolute static pressure (in bars absolute)
Q = airflow (kg/s).
When the anti-ice valve is open, the information is fed to the Air Conditioning System Controller (ACSC). The latter determines the configuration of the engine bleed air to control the FADEC: this decreases the EPR limit relative to the ambient conditions, the engine operating conditions and the load of the anti-ice bleed.
The air bled from the seventh stage of the HP compressor passes through four duct sections and line-mounted valve of the on-off type. At the forward bulkhead of the intake cowl, the anti-ice system interfaces with the piccolo tube in the intake lip. The spent air then exhausts overboard via the exhaust sleeve/flush duct assembly.
The airflow pressure is controlled by an anti ice valve which is of the butterfly type and electrically operated. The safety position of the valve is fully open.
The flow factor is:
ff = QxSQR(T5)/P5
T5 = absolute total temperature (in deg. K)
P5 = absolute static pressure (in bars absolute)
Q = airflow (kg/s).
When the anti-ice valve is open, the information is fed to the Air Conditioning System Controller (ACSC). The latter determines the configuration of the engine bleed air to control the FADEC: this decreases the EPR limit relative to the ambient conditions, the engine operating conditions and the load of the anti-ice bleed.
B. Control and Indicating
Ice Protection of the Engine Air Intakes - Indications on Upper ECAM Display Unit ** ON A/C NOT FOR ALL
The control and indicating components are located on the overhead panel, on the ANTI ICE section of panel 25VU. Two pushbutton switches designated ENG 1 and ENG 2 are available, each associated with one engine.
Each pushbutton switch includes two luminous legends:
Ice Protection of the Engine Air Intakes - Indications on Upper ECAM Display Unit ** ON A/C NOT FOR ALL Each pushbutton switch includes two luminous legends:
- ON: blue,
- FAULT: amber.
(1) When you release the pushbutton switch, the ON legend is off and the system is not selected on.
(2) When you push the pushbutton switch, the ON legend is on and the system is selected on.
(3) Illumination of the FAULT legend indicates:
(a) With the ON legend off, the following failure:
- the anti ice valve is not fully closed.
It is necessary to push the ENG 1(2) pushbutton switch to extinguish the FAULT legend: the ON legend comes on.
(b) If the ON legend is on, the following failure:
- the anti ice valve is not fully open.
It is necessary to release the ENG 1(2) pushbutton switch to extinguish the FAULT legend: the ON legend goes off.
If failure of the anti ice valve is detected on the ground, it is possible to lock the valve butterfly in either the open or closed position for the next flight.
(4) The ENG ANTI ICE ON indication is displayed in green on the MEMO page on the lower part of the upper ECAM display unit if at least one of the two ice protection systems of the engine air intakes is selected on.
(5) Central warnings
Illumination of the FAULT legend of the ENG 1(2) pushbutton switch is accompanied by activation of the ECAM system:
Illumination of the FAULT legend of the ENG 1(2) pushbutton switch is accompanied by activation of the ECAM system:
- activation of the single chime,
- flashing of the amber MASTER CAUT light,
- warning display on the lower part of the upper ECAM display unit.