DOC AIRBUS | AMM A320FTHRUST REVERSER HALVES - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
1. General
The thrust reverser assembly is made of two halves that are attached to the pylon immediately aft of the engine fan case. Each half is supported by hinges at the pylon and latched together at the bottom with hook tension latches. When these halves are latched, they form part of the aerodynamic smooth surface of the complete engine nacelle. Each thrust reverser half has an internal kidney-shaped duct that guides the air from the fan to the exhaust nozzle at the rear of the engine. Opening the thrust reverser gives maintainers access to the engine core compartment and Line Replaceable Units (LRUs) of the thrust reverser.
** ON A/C NOT FOR ALL The thrust reverser assembly is made of two halves that are attached to the pylon immediately aft of the engine fan case. Each half is supported by hinges at the pylon and latched together at the bottom with hook tension latches. When these halves are latched, they form part of the aerodynamic smooth surface of the complete engine nacelle. Each thrust reverser half has an internal kidney-shaped duct that guides the air from the fan to the exhaust nozzle at the rear of the engine. Opening the thrust reverser gives maintainers access to the engine core compartment and Line Replaceable Units (LRUs) of the thrust reverser.
2. System Description
Thrust Reverser HalvesA. General
Each thrust reverser half is supported from the pylon by four hinges which are part of an aluminum beam on the upper section of the thrust reverser. Each half has the following main components: the inner fixed structure, translating sleeve, blocker doors and cascades. Each thrust reverser half has hoisting points for removal and installation with the use of a hoisting sling.
Each thrust reverser half is supported from the pylon by four hinges which are part of an aluminum beam on the upper section of the thrust reverser. Each half has the following main components: the inner fixed structure, translating sleeve, blocker doors and cascades. Each thrust reverser half has hoisting points for removal and installation with the use of a hoisting sling.
B. Inner Fixed Structure (IFS)
The IFS assembly is a composite and titanium structure that encloses the engine compartment. The outer surface of the IFS has perforated skin that decreases engine noise and supplies an aerodynamic, smooth surface for fan air. The IFS assembly houses the cascades, provides attachment points for the actuators, and supports the translating sleeve. It has a hinge beam, latch beam, thermal blankets, seals, a Bifurcation Latch System (BLS) and a pressure relief door. The right hand IFS has a duct in the upper bifurcation wall which supplies air to the pre-cooler. It also has an inlet for the Active Clearance Control (ACC) valve which supplies air to cool the turbine case area. The left hand IFS has an inlet which supplies air to the Air Cooled Oil Cooler (ACOC).
The IFS assembly is a composite and titanium structure that encloses the engine compartment. The outer surface of the IFS has perforated skin that decreases engine noise and supplies an aerodynamic, smooth surface for fan air. The IFS assembly houses the cascades, provides attachment points for the actuators, and supports the translating sleeve. It has a hinge beam, latch beam, thermal blankets, seals, a Bifurcation Latch System (BLS) and a pressure relief door. The right hand IFS has a duct in the upper bifurcation wall which supplies air to the pre-cooler. It also has an inlet for the Active Clearance Control (ACC) valve which supplies air to cool the turbine case area. The left hand IFS has an inlet which supplies air to the Air Cooled Oil Cooler (ACOC).
(1) The IFS thermal blankets are installed over the PRD latch and on the inner side of the IFS. These thermal blankets are in sections and attached with click bond fasteners. The thermal blankets are made of insulation sandwiched between two thin sheets of steel foil.
(2) The function of the fire seals is to supply a fire barrier of the engine core compartment and prevent secondary air flow from leaking into the engine compartment. This makes a smooth, aerodynamic duct for fan air. The function of the ACOC and ACC seals is to supply a sealing interface so that there is a correct supply of cooling air.
(3) The function of the BLS is to latch the two thrust reverser halves together and to prevent gaps in the fire seals in the event of a burst duct. The BLS latch is painted fluorescent orange so it will be visible when the latch is not closed.
(4) If there is a burst duct, the pressure relief door prevents pressure from building in the IFS and causing gaps in the fire seals of the upper pylon. The pressure relief door is made of titanium so that it is light weight and resists high temperatures.
C. Translating Sleeve
The translating sleeve forms the outer surface of each thrust reverser half. It is installed in primary and auxiliary slider tracks at the top and the bottom of each thrust reverser half. In the forward thrust position, the translating sleeve is forward and covers the cascades, which provides an aerodynamically smooth surface to the engine nacelle. In the reverse thrust position, the translating sleeve moves aft on the slider tracks, which exposes the cascades while the blocker doors rotate inward. This blocks the flow of fan air coming into the duct and directs it outward and forward through the cascades. The translating sleeve has inner and outer panels, blocker doors, actuators, sliders and seals.
The translating sleeve forms the outer surface of each thrust reverser half. It is installed in primary and auxiliary slider tracks at the top and the bottom of each thrust reverser half. In the forward thrust position, the translating sleeve is forward and covers the cascades, which provides an aerodynamically smooth surface to the engine nacelle. In the reverse thrust position, the translating sleeve moves aft on the slider tracks, which exposes the cascades while the blocker doors rotate inward. This blocks the flow of fan air coming into the duct and directs it outward and forward through the cascades. The translating sleeve has inner and outer panels, blocker doors, actuators, sliders and seals.
D. Blocker Doors
There are ten blocker doors that move and rotate with the translating sleeve. They attach to the inner surface of the translating sleeve and also to drag links on the IFS. In the stowed position, the blocker doors lay flat against the inner surface of the translating sleeve to make an aerodynamic smooth surface for fan air flow. During the deploy cycle, the drag links rotate the blocker doors into the fan duct. This redirects the fan air flow through the cascades. Each cowl half has five blocker doors with aluminum honeycomb core and composite skin. The skin is perforated to decrease noise from the engine.
There are ten blocker doors that move and rotate with the translating sleeve. They attach to the inner surface of the translating sleeve and also to drag links on the IFS. In the stowed position, the blocker doors lay flat against the inner surface of the translating sleeve to make an aerodynamic smooth surface for fan air flow. During the deploy cycle, the drag links rotate the blocker doors into the fan duct. This redirects the fan air flow through the cascades. Each cowl half has five blocker doors with aluminum honeycomb core and composite skin. The skin is perforated to decrease noise from the engine.
E. Cascades
There are seven composite cascades that are part of the thrust reverser duct structure. These are attached to the torque box and aft support ring in a semicircular shape on each cowl half. Each cascade has curved vanes. These vanes direct the fan exhaust air at different angles forward and away from the engine for reverse thrust. Each cascade is removable and non-interchangeable.
There are seven composite cascades that are part of the thrust reverser duct structure. These are attached to the torque box and aft support ring in a semicircular shape on each cowl half. Each cascade has curved vanes. These vanes direct the fan exhaust air at different angles forward and away from the engine for reverse thrust. Each cascade is removable and non-interchangeable.