DOC AIRBUS | AMM A320FTHRUST REVERSER STRUCTURE - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
1. General
The thrust reverser is attached to the pylon immediately aft of the engine fan case. When stowed, the reverser forms a continuation of the engine fan exhaust nozzle and when deployed, the reverser directs the fan exhaust forwards.
The reverser is constructed in two halves that form a bifurcated duct. The reverser halves are hinged at the top to the pylon, clamped to the aft outer flange of the fan case and latched along the bottom centerline.
The two complete thrust reverser cowls are wing interchangeable.
** ON A/C NOT FOR ALL The thrust reverser is attached to the pylon immediately aft of the engine fan case. When stowed, the reverser forms a continuation of the engine fan exhaust nozzle and when deployed, the reverser directs the fan exhaust forwards.
Fan Thrust Reverser Structure - Cut away ViewThe reverser is constructed in two halves that form a bifurcated duct. The reverser halves are hinged at the top to the pylon, clamped to the aft outer flange of the fan case and latched along the bottom centerline.
The two complete thrust reverser cowls are wing interchangeable.
2. Description
A. Fixed Structure
Each thrust Reverser half is supported from the pylon by three hinges.
These hinges are integral with a machined aluminium beam which runs along the upper portion of the thrust reverser.
Each thrust Reverser half is supported from the pylon by three hinges.
These hinges are integral with a machined aluminium beam which runs along the upper portion of the thrust reverser.
(1) Outer Barrel
The outer barrel forms the fan flow outer contour. In stow position, blocker doors are parts of the outer cowl. The outer barrel has a composite honeycomb structure. It consists of graphite skins bonded to Nomex honeycomb.
The outer barrel forms the fan flow outer contour. In stow position, blocker doors are parts of the outer cowl. The outer barrel has a composite honeycomb structure. It consists of graphite skins bonded to Nomex honeycomb.
(2) Inner Barrel
The inner barrel forms the fan flow inner contour and engine outer envelope.
The thrust reverser inner barrel panel incorporates four flush inlet holes in the forward section that allow cooling air from the fan duct into the engine core compartment. These holes, along with the LPT cooling system discharge air, provide the cooling and ventilation for the engine core compartment. Air passes through the compartment and is exhausted out of the annular opening between the thrust reverser and the core nozzle. Right thrust reverser incorporates a flush inlet for precooler cold air. The inner barrel is acoustically treated. It consists of aluminium perforated face sheet bonded to aluminium honeycomb core. The inner (engine side) surface of the inner barrel is treated for thermal/fire protection.
The inner barrel is protected by a DARCHEM fire blanket. The blanket consists of a back-skin No.3 crimp stainless steel 0.05 mm thick and a front skin No.3 crimp stainless steel 0.075mm thick. Internal insulation consists of TRITON fibre 9 mm compressed to 8 mm. A sufficient quantity of breathers are provided to ensure acceptable air flow permeability. The blanket is attached to the inner cowl using a hook and latch method.
The forward section of the inner barrel is protected with MA25 S ablative coating.
The inner barrel forms the fan flow inner contour and engine outer envelope.
The thrust reverser inner barrel panel incorporates four flush inlet holes in the forward section that allow cooling air from the fan duct into the engine core compartment. These holes, along with the LPT cooling system discharge air, provide the cooling and ventilation for the engine core compartment. Air passes through the compartment and is exhausted out of the annular opening between the thrust reverser and the core nozzle. Right thrust reverser incorporates a flush inlet for precooler cold air. The inner barrel is acoustically treated. It consists of aluminium perforated face sheet bonded to aluminium honeycomb core. The inner (engine side) surface of the inner barrel is treated for thermal/fire protection.
The inner barrel is protected by a DARCHEM fire blanket. The blanket consists of a back-skin No.3 crimp stainless steel 0.05 mm thick and a front skin No.3 crimp stainless steel 0.075mm thick. Internal insulation consists of TRITON fibre 9 mm compressed to 8 mm. A sufficient quantity of breathers are provided to ensure acceptable air flow permeability. The blanket is attached to the inner cowl using a hook and latch method.
The forward section of the inner barrel is protected with MA25 S ablative coating.
(3) Forward frame
The forward frame supports all the hydraulic system, HCU, latches, actuators, the stow switches and the "V" blade which interfaces with the fan frame (Ref. 78-36-00) (except the SOV which is on the pylon).
The forward frame supports all the hydraulic system, HCU, latches, actuators, the stow switches and the "V" blade which interfaces with the fan frame (Ref. 78-36-00) (except the SOV which is on the pylon).
(4) Ramp
The ramp serves to deflect the air when the blocker doors are deployed. It is a composite honeycomb structure. Graphite composite skins are bonded to aluminium honeycomb.
The ramp fairing considered represent 470 mm of the fan duct zone not covered.
The ramp serves to deflect the air when the blocker doors are deployed. It is a composite honeycomb structure. Graphite composite skins are bonded to aluminium honeycomb.
The ramp fairing considered represent 470 mm of the fan duct zone not covered.
(5) Materials
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| COMPONENT MATERIAL |
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| Hinge 2024 AL |
| Inner Barrel 7227 or 7237 AL skins, |
| 5052 AL honeycomb core |
| Outer Barrel Graphite skins, Nomex |
| honeycomb core |
| Blocker Door 7227 or 7237 AL skins, |
| 5052 AL honeycomb core |
| for inner panel and |
| graphite skins, Nomex |
| honeycomb core for outer |
| panel |
| Ramps Graphite skins, |
| 5052 honeycomb core |
| Forward Frame 2024 AL |
| Beams AS7G06 and 2024 AL |
(6) Fire protection
The thrust reverser is the boundary of 2 designated fire zones. The fan compartment and the core compartment.
The fan compartment is bounded by the thrust reverser forward frame and the 6 o'clock engine pipe cavity, which consists of stainless steel/titanium fireshields. Fireseals are utilized at locations where the thrust reverser abutts adjacent structure. The core compartment is bounded by the engine case interfaces forward and aft and the opposite reverser half at the remaining interfaces. All interfaces are fireproof. This is obtained by the use of fireproof seals, or due to the material properties as far as the V-groove and J-ring are concerned.
The thrust reverser is the boundary of 2 designated fire zones. The fan compartment and the core compartment.
The fan compartment is bounded by the thrust reverser forward frame and the 6 o'clock engine pipe cavity, which consists of stainless steel/titanium fireshields. Fireseals are utilized at locations where the thrust reverser abutts adjacent structure. The core compartment is bounded by the engine case interfaces forward and aft and the opposite reverser half at the remaining interfaces. All interfaces are fireproof. This is obtained by the use of fireproof seals, or due to the material properties as far as the V-groove and J-ring are concerned.
(7) Pressure relief
The reverser incorporates a pressure relief system which prevents permanent structural deformation in the event of a single bleed duct rupture in combination with external air loading throughout the flight envelope.
It consists of an annular opening between the thrust reverser and the core compartment.
The reverser incorporates a pressure relief system which prevents permanent structural deformation in the event of a single bleed duct rupture in combination with external air loading throughout the flight envelope.
It consists of an annular opening between the thrust reverser and the core compartment.
(8) Drainage
Drainage of the core compartment is provided by a dedicated drain tube located on engine center line at the lowest part of the core cowl and runs vertically venting directly to ambient.
Drainage of the core compartment is provided by a dedicated drain tube located on engine center line at the lowest part of the core cowl and runs vertically venting directly to ambient.
(1) General
Two blocker doors are installed onto each half reverser. Each blocker door rotates around pins secured onto upper and lower fittings located at 3 and 9 o'clock. All the blockers doors are actuated by hydraulic actuators and rotate independently.
Two blocker doors are installed onto each half reverser. Each blocker door rotates around pins secured onto upper and lower fittings located at 3 and 9 o'clock. All the blockers doors are actuated by hydraulic actuators and rotate independently.
NOTE: All doors are different.
(3) Efflux Pattern
The reverser is designed in such a way that :
The reverser is designed in such a way that :
- there is no direct impingement of the flow onto the wing under normal operating conditions
- no occurrences of reingestion under normal operating conditions
- a minimum of unbalanced thrust forces.
- the shape of the reverser openings.
- the height and shape of the kicker-plate at the leading edge of each reverser blocker door.
- shape of the forward internal skin of the reverser blocker door.
- side walls along the edge of the blocker doors.
The configuration of the right thrust reverser is different from the left one.
(4) Seals
The characteristics of the seals are :
The characteristics of the seals are :
- large diameter seal
- pressurized seal
- silicone and fiber glass material
- no seal scrubbing during door motion
- seal in compression
- each seal is particular to one component with no angle.