DOC AIRBUS | AMM A320FAIR INTAKE - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
1. General
A. General Description
(1) The air intake cowl is an interchangeable aerodynamic cowl installed at the front of the engine. The functions of the inlet cowl are:
- To supply airflow to the fan and to the engine core
- To provide a smooth aerodynamic surface to the airflow
- To provide acoustic treatment for noise reduction
- Anti-icing in the nacelle.
(2) The air intake cowl has:
- An outer barrel
- An inner barrel (acoustic panel)
- Nose lip assembly and anti-icing system
- Forward bulkhead
- Aft bulkhead
- Access doors.
B. Component
(1) Outer Barrel
The outer barrel has three Carbon Fiber Reinforced Plastic (CFRP) sections. The three sections are assembled with splices. The forward edge of each panel is attached to the forward bulkhead and the aft edge of each panel is attached to the aft bulkhead.
At the top of the outer barrel, a ventilation scoop decreases the temperature of the fan-cowl compartment zone.
A FADEC cooling assembly is installed between the 3 o'clock and 4 o'clock positions on the outer barrel. This is to supply airflow to the FADEC blower.
A drain hole at the bottom of the outer barrel does not let water collect in the barrel.
The outer barrel has three Carbon Fiber Reinforced Plastic (CFRP) sections. The three sections are assembled with splices. The forward edge of each panel is attached to the forward bulkhead and the aft edge of each panel is attached to the aft bulkhead.
At the top of the outer barrel, a ventilation scoop decreases the temperature of the fan-cowl compartment zone.
A FADEC cooling assembly is installed between the 3 o'clock and 4 o'clock positions on the outer barrel. This is to supply airflow to the FADEC blower.
A drain hole at the bottom of the outer barrel does not let water collect in the barrel.
(2) Inner Barrel
The inner barrel has three sections. The outer section is made of CFRP and gives structural strength. The middle layer is made of Nomex and decreases engine noise. The inner layer is made of corrosion-resistant steel wire-mesh to give structural strength.
Two drain holes at the bottom of the inner barrel do not let water collect in the barrel.
The inner barrel has three sections. The outer section is made of CFRP and gives structural strength. The middle layer is made of Nomex and decreases engine noise. The inner layer is made of corrosion-resistant steel wire-mesh to give structural strength.
Two drain holes at the bottom of the inner barrel do not let water collect in the barrel.
(3) Nose Lip Assembly and Anti-Icing System
The nose lip assembly is made of aluminum alloy. The nose lip assembly and the forward bulkhead make a chamber. In this chamber, a cyclone-type anti-icing system (O-ring injector) is attached to the forward bulkhead. The air from the engine is supplied to the cyclone system through the anti-icing ducts (supply duct and shroud duct) through the aft bulkhead. The anti-icing system can operate in all the flight and ground conditions.
The inner surface of the nose lip assembly has a high-temperature paint to prevent corrosion and provide thermal protection.
A drain hole at the bottom does not let water collect in the nose lip assembly.
A nose lip exhaust-grid releases the anti-icing air overboard between the 5 o'clock and 6 o'clock positions of the nose lip.
The nose lip assembly is made of aluminum alloy. The nose lip assembly and the forward bulkhead make a chamber. In this chamber, a cyclone-type anti-icing system (O-ring injector) is attached to the forward bulkhead. The air from the engine is supplied to the cyclone system through the anti-icing ducts (supply duct and shroud duct) through the aft bulkhead. The anti-icing system can operate in all the flight and ground conditions.
The inner surface of the nose lip assembly has a high-temperature paint to prevent corrosion and provide thermal protection.
A drain hole at the bottom does not let water collect in the nose lip assembly.
A nose lip exhaust-grid releases the anti-icing air overboard between the 5 o'clock and 6 o'clock positions of the nose lip.
(4) Forward Bulkhead
The forward bulkhead is the primary structural part of the inlet cowl assembly. It gives structural strength to the inlet cowl assembly. The forward bulkhead is made of titanium.
Rivets attach the nose lip assembly to the forward bulkhead.
The nozzle of the anti-icing system is attached to the forward bulkhead.
The forward bulkhead is the primary structural part of the inlet cowl assembly. It gives structural strength to the inlet cowl assembly. The forward bulkhead is made of titanium.
Rivets attach the nose lip assembly to the forward bulkhead.
The nozzle of the anti-icing system is attached to the forward bulkhead.
(5) Aft Bulkhead
The aft bulkhead also gives structural strength to the inlet cowl assembly. The aft bulkhead is made of CFRP.
Four locators are installed on the aft bulkhead ring. The locator plates are made of INCO718 and the locator supports are made of titanium. The primary functions of the locators are as follows:
An aft bulkhead ring made of titanium, gives structural strength to the inlet cowl assembly.
The aft bulkhead also gives structural strength to the inlet cowl assembly. The aft bulkhead is made of CFRP.
Four locators are installed on the aft bulkhead ring. The locator plates are made of INCO718 and the locator supports are made of titanium. The primary functions of the locators are as follows:
- Hold the fan cowl in the correct position during the flight
- Make sure that the fan cowl opens and closes correctly
- Give lightning strike protection.
An aft bulkhead ring made of titanium, gives structural strength to the inlet cowl assembly.
(6) Access Doors
The air intake cowl has the three access doors that follow:
The nose anti-icing door gives access to the Nacelle Anti-Ice (NAI) ducts for maintenance. It also protects the outer barrel from the hot air flow that comes from the NAI system.
The T12 maintenance door gives access to the T12 probe for maintenance.
The air intake cowl has the three access doors that follow:
- The retrieval door
- The nose anti-icing door
- The T12 maintenance door.
The nose anti-icing door gives access to the Nacelle Anti-Ice (NAI) ducts for maintenance. It also protects the outer barrel from the hot air flow that comes from the NAI system.
The T12 maintenance door gives access to the T12 probe for maintenance.
C. Location
The air inlet cowl and its components are installed on the front of the engine.
The air inlet cowl and its components are installed on the front of the engine.
Air IntakeD. Operation
(1) Fan-Cowl Compartment Airflow
The air from the ventilation scoop goes through the distributor assembly:
The air from the ventilation scoop goes through the distributor assembly:
- To make sure that there is a good airflow. This will not let flammable liquid collect at the distributor.
- To decrease the temperature
- To let the extinguishing agent spread equally in the fan cowl compartment, if a fire occurs.
(2) NAI System
The NAI system does not let ice collect on the nose lip assembly. Hot air from the engine goes from the aft bulkhead to the forward bulkhead and nose lip assembly through the anti-icing duct.
The NAI system does not let ice collect on the nose lip assembly. Hot air from the engine goes from the aft bulkhead to the forward bulkhead and nose lip assembly through the anti-icing duct.