DOC AIRBUS | AMM A320FFAN COWL - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
1. General
The fan cowl door assemblies are interchangeable units. They enclose the engine fan case between the air intake cowl and thrust reverser. Each fan cowl door assembly incorporates strakes. Each assembly is supported by three hinges at the pylon and latched along the bottom centerline with three adjustable tension hook latches.
The fan cowl door assemblies are interchangeable units. They enclose the engine fan case between the air intake cowl and thrust reverser. Inboard fan cowl door of each nacelle incorporates strakes. Each assembly is supported by three hinges at the pylon and latched along the bottom centerline with three adjustable tension hook latches.
** ON A/C NOT FOR ALL The fan cowl door assemblies are interchangeable units. They enclose the engine fan case between the air intake cowl and thrust reverser. Each fan cowl door assembly incorporates strakes. Each assembly is supported by three hinges at the pylon and latched along the bottom centerline with three adjustable tension hook latches.
Fan Cowl DoorsThe fan cowl door assemblies are interchangeable units. They enclose the engine fan case between the air intake cowl and thrust reverser. Inboard fan cowl door of each nacelle incorporates strakes. Each assembly is supported by three hinges at the pylon and latched along the bottom centerline with three adjustable tension hook latches.
2. Description
The fan cowls are bonded graphite epoxy skins and aluminum honeycomb sandwich construction.
A land is effected with the air intake cowl at the forward end, and with the fan thrust reverser at the aft end.
Both lands incorporate an edge protector. The forward land incorporates two fan cowl locator fittings (associated with air intake cowl alignment fitting).
A composite outer skin of the fan cowl incorporates a lightning protection system consisting of an expanded copper screen (ECS) material. This material enables the fan cowl to satisfy Zone 1A lightning strike requirements.
A bulb-type seal is provided along the lower longitudinal splitline and a sheet metal rub strip is provided along the upper longitudinal splitline which interfaces with a pylon mounted sheet metal seal.
Strakes are installed on the right and the left side of the fan cowl doors of each engine.
An electrical bonding strip, which is connected to the strake backplate and the fan cowl locator blade provides an electrical bond between the strake and the engine.
The fan cowls are bonded graphite epoxy skins and aluminum honeycomb sandwich construction.
A land is effected with the air intake cowl at the forward end, and with the fan thrust reverser at the aft end.
Both lands incorporate an edge protector. The forward land incorporates two fan cowl locator fittings (associated with air intake cowl alignment fitting).
A composite outer skin of the fan cowl incorporates a lightning protection system consisting of an expanded copper screen (ECS) material. This material enables the fan cowl to satisfy Zone 1A lightning strike requirements.
A bulb-type seal is provided along the lower longitudinal splitline and a sheet metal rub strip is provided along the upper longitudinal splitline which interfaces with a pylon mounted sheet metal seal.
Strakes are installed on the inboard fan cowl door of each engine.
An electrical bonding strip, which is connected to the strake backplate and the fan cowl locator blade provides an electrical bond between the strake and the engine.
** ON A/C NOT FOR ALL The fan cowls are bonded graphite epoxy skins and aluminum honeycomb sandwich construction.
A land is effected with the air intake cowl at the forward end, and with the fan thrust reverser at the aft end.
Both lands incorporate an edge protector. The forward land incorporates two fan cowl locator fittings (associated with air intake cowl alignment fitting).
A composite outer skin of the fan cowl incorporates a lightning protection system consisting of an expanded copper screen (ECS) material. This material enables the fan cowl to satisfy Zone 1A lightning strike requirements.
A bulb-type seal is provided along the lower longitudinal splitline and a sheet metal rub strip is provided along the upper longitudinal splitline which interfaces with a pylon mounted sheet metal seal.
Strakes are installed on the right and the left side of the fan cowl doors of each engine.
An electrical bonding strip, which is connected to the strake backplate and the fan cowl locator blade provides an electrical bond between the strake and the engine.
The fan cowls are bonded graphite epoxy skins and aluminum honeycomb sandwich construction.
A land is effected with the air intake cowl at the forward end, and with the fan thrust reverser at the aft end.
Both lands incorporate an edge protector. The forward land incorporates two fan cowl locator fittings (associated with air intake cowl alignment fitting).
A composite outer skin of the fan cowl incorporates a lightning protection system consisting of an expanded copper screen (ECS) material. This material enables the fan cowl to satisfy Zone 1A lightning strike requirements.
A bulb-type seal is provided along the lower longitudinal splitline and a sheet metal rub strip is provided along the upper longitudinal splitline which interfaces with a pylon mounted sheet metal seal.
Strakes are installed on the inboard fan cowl door of each engine.
An electrical bonding strip, which is connected to the strake backplate and the fan cowl locator blade provides an electrical bond between the strake and the engine.
3. Opening/Closing
There are two telescopic hold open rods on each door. The hold open rods lock to brackets on the engine fan case. They support the fan cowl doors in the open position. A 40-degree position serves for routine maintenance and a 55-degree position serves for increased access.
Three hook type latches are provided on the left hand door, and mating adjusta-keeper clevis on the right hand door. The bottom seal pressure between the doors is adjustable by varying the shim pack thickness behind the latch striker pads. The latch handle closing pressure is adjustable with the fan cowl doors closed.
** ON A/C NOT FOR ALL There are two telescopic hold open rods on each door. The hold open rods lock to brackets on the engine fan case. They support the fan cowl doors in the open position. A 40-degree position serves for routine maintenance and a 55-degree position serves for increased access.
Three hook type latches are provided on the left hand door, and mating adjusta-keeper clevis on the right hand door. The bottom seal pressure between the doors is adjustable by varying the shim pack thickness behind the latch striker pads. The latch handle closing pressure is adjustable with the fan cowl doors closed.
4. Access Doors/Pressure Relief Door
A combination access/pressure relief door is provided in the right-hand fan cowl door for access to the starter valve manual override. This door also acts as a pressure relief door to protect the door structure in the event of a burst duct. The left-hand fan cowl door includes an access door for engine oil servicing and inspection of the hydraulic case drain filter clogging indicator and master oil chip detector indicator. The air outlet vent is located in the right-hand cowl panel lower aft section. The fan cowl doors are fireproof without external air flow above the 45-degree radial and fireproof with external air flow below the 45-degree radial. In addition, the doors are fire resistant without external air flow below the 45-degree radial.
A combination access/pressure relief door is provided in the right-hand fan cowl door for access to the starter valve manual override. This door also acts as a pressure relief door to protect the door structure in the event of a burst duct. The left-hand fan cowl door includes an access door for engine oil servicing and inspection of the hydraulic case drain filter clogging indicator and master oil chip detector indicator. The air outlet vent is located in the right-hand cowl panel lower aft section. The fan cowl doors are fireproof without external air flow above the 45-degree radial and fireproof with external air flow below the 45-degree radial. In addition, the doors are fire resistant without external air flow below the 45-degree radial.
IDG Viewing door.
A viewing door is installed in the forward lower section of the right fan cowl door. The viewing door provides access to do a check of the IDG oil level without opening the fan cowl door. The door has quick release fasteners for easy access and a landyard to hold the door when it is open.
** ON A/C NOT FOR ALL A combination access/pressure relief door is provided in the right-hand fan cowl door for access to the starter valve manual override. This door also acts as a pressure relief door to protect the door structure in the event of a burst duct. The left-hand fan cowl door includes an access door for engine oil servicing and inspection of the hydraulic case drain filter clogging indicator and master oil chip detector indicator. The air outlet vent is located in the right-hand cowl panel lower aft section. The fan cowl doors are fireproof without external air flow above the 45-degree radial and fireproof with external air flow below the 45-degree radial. In addition, the doors are fire resistant without external air flow below the 45-degree radial.
A combination access/pressure relief door is provided in the right-hand fan cowl door for access to the starter valve manual override. This door also acts as a pressure relief door to protect the door structure in the event of a burst duct. The left-hand fan cowl door includes an access door for engine oil servicing and inspection of the hydraulic case drain filter clogging indicator and master oil chip detector indicator. The air outlet vent is located in the right-hand cowl panel lower aft section. The fan cowl doors are fireproof without external air flow above the 45-degree radial and fireproof with external air flow below the 45-degree radial. In addition, the doors are fire resistant without external air flow below the 45-degree radial.
IDG Viewing door.
A viewing door is installed in the forward lower section of the right fan cowl door. The viewing door provides access to do a check of the IDG oil level without opening the fan cowl door. The door has quick release fasteners for easy access and a landyard to hold the door when it is open.
5. Fan Cowl Structure
The internal pressure loads and external air loads are reacted through the honeycomb structure. They are transmitted into the pylon through the hinge fittings. The door lands provide support to prevent deflection under pressure. The cowl doors, when completely latched, provide hoop continuity.
The cowl doors are designed to be structurally adequate when any one latch is unlatched or any one hinge failed. A nacelle overpressurization condition due to a pneumatic duct failure is released through the pressure relief door. The pressure relief doors are designed to prevent fan compartment pressure from exceeding 4 psid (0.28 bar).
** ON A/C NOT FOR ALL The internal pressure loads and external air loads are reacted through the honeycomb structure. They are transmitted into the pylon through the hinge fittings. The door lands provide support to prevent deflection under pressure. The cowl doors, when completely latched, provide hoop continuity.
The cowl doors are designed to be structurally adequate when any one latch is unlatched or any one hinge failed. A nacelle overpressurization condition due to a pneumatic duct failure is released through the pressure relief door. The pressure relief doors are designed to prevent fan compartment pressure from exceeding 4 psid (0.28 bar).
6. Fan Cowl Materials
The fan cowl structural assembly is a bonded composite skin and a aluminium honeycomb sandwich structure with provisions for attaching hinge fittings, latch fittings, access doors, hold open rods, and air vents. See the following table for component materials.
** ON A/C NOT FOR ALL The fan cowl structural assembly is a bonded composite skin and a aluminium honeycomb sandwich structure with provisions for attaching hinge fittings, latch fittings, access doors, hold open rods, and air vents. See the following table for component materials.
| Fan Cowl Component Materials |
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| COMPONENT MATERIAL |
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| Skins Graphite epoxy tape and fabric |
| Core 5052 or 5056 aluminium honeycomb |
| Hinges 17-4PH steel casting |
| Latch housing 17-4PH steel casting |
| Adjusta-keeper clevis housing 17-4PH steel casting |
| Hold open rod Graphite epoxy fabric tubes |
| aluminium end fittings |
7. Fan Cowl Removal/Installation
Each fan cowl assembly (left and right) is attached to the pylon by three hinge fittings.
Each fan cowl assembly (left and right) is attached to the pylon by three hinge fittings.