DOC AIRBUS | AMM A320FRAPID DECOMPRESSION SAFETY SYSTEM - DESCRIPTION AND OPERATION
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1. General
A rapid-decompression safety-system is installed in the aircraft.
** ON A/C NOT FOR ALL A rapid-decompression safety-system is installed in the aircraft.
2. Component Location
Component Location ** ON A/C NOT FOR ALL
Component Location ** ON A/C NOT FOR ALL
Component Location ** ON A/C NOT FOR ALL
Component Details ** ON A/C NOT FOR ALL
Component Details ** ON A/C NOT FOR ALL
Component Details ** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL Component Location ** ON A/C NOT FOR ALL Component Location ** ON A/C NOT FOR ALL Component Location ** ON A/C NOT FOR ALL Component Details ** ON A/C NOT FOR ALL Component Details ** ON A/C NOT FOR ALL Component Details ** ON A/C NOT FOR ALL 3. System Description
The rapid-decompression safety-system prevents a pressure difference between different closed areas in the aircraft (for example; cockpit/cabin, cabin/cargo compartment) if a rapid decompression occurs. This prevents structural damage to the fuselage and damage to the equipment and furnishings, installed in these areas.
The rapid-decompression safety-system has:
** ON A/C NOT FOR ALL The rapid-decompression safety-system prevents a pressure difference between different closed areas in the aircraft (for example; cockpit/cabin, cabin/cargo compartment) if a rapid decompression occurs. This prevents structural damage to the fuselage and damage to the equipment and furnishings, installed in these areas.
The rapid-decompression safety-system has:
- Rapid-decompression panels (cargo compartments).
- Dado panels (cabin) (Ref. AMM D/O 25-23-00-00).
- Air grills (stowages and lavatories).
- Cockpit door (Ref. AMM D/O 52-51-00-00).
4. Component Description
A. Rapid-Decompression Panels
Component Location ** ON A/C NOT FOR ALL
Component Location ** ON A/C NOT FOR ALL
Component Location ** ON A/C NOT FOR ALL
The rapid-decompression panel has these components:
The rapid-decompression panel has these components:
Component Location ** ON A/C NOT FOR ALL Component Location ** ON A/C NOT FOR ALL Component Location ** ON A/C NOT FOR ALL The rapid-decompression panel has these components:
- Decompression panels.
- Decompression frames.
- Latch assemblies.
- Fasteners.
The rapid-decompression panel has these components:
- Decompression panels.
- Decompression frames.
- Latch assemblies.
- Protection devices.
(1) Decompression Panel
The panels have a composite structure made of a honeycomb-core and a flame-retardant laminated-skin. On one side of the panel the laminated-skin is extended and makes a border around the honeycomb-filling. This side of the panel completes the lining of the cargo compartment on the inner side.
The border is cut at each corner. The cut starts at the edge of the border and continues diagonally to the corner of the honeycomb-filling. Sealing tape is bonded to the side of the border that touches the inner lining of the cargo compartment. The cuts in the border are sealed with this tape.
The panels have a composite structure made of a honeycomb-core and a flame-retardant laminated-skin. On one side of the panel the laminated-skin is extended and makes a border around the honeycomb-filling. This side of the panel completes the lining of the cargo compartment on the inner side.
The border is cut at each corner. The cut starts at the edge of the border and continues diagonally to the corner of the honeycomb-filling. Sealing tape is bonded to the side of the border that touches the inner lining of the cargo compartment. The cuts in the border are sealed with this tape.
(2) Frame
The frame is covered with flame-retardant material, attached with adhesive tape. The frame is installed on the decompression panel, on the side that faces out from the cargo compartment.
The frame is covered with flame-retardant material, attached with adhesive tape. The frame is installed on the decompression panel, on the side that faces out from the cargo compartment.
(3) Latch Assembly
The latch assembly has a housing, which includes a latch and a spring. The latch has a shaped end and is always in the closed position. To open the latch assembly you push the latch back into its housing, against the spring tension. The latch assemblies are installed on the decompression panel on the side that faces out from the cargo compartment.
The latch assembly has a housing, which includes a latch and a spring. The latch has a shaped end and is always in the closed position. To open the latch assembly you push the latch back into its housing, against the spring tension. The latch assemblies are installed on the decompression panel on the side that faces out from the cargo compartment.
(4) Protection Devices
The protection devices are installed with screws to the ceiling-panels around each decompression-panel. The protection devices still permit the full function of (BLOW-IN) or (BLOW-OUT) for the decompression-panels. The protection devices protect the decompression-panels against impact from "X" and "Y" directions of misaligned luggage.
The protection devices are installed with screws to the ceiling-panels around each decompression-panel. The protection devices still permit the full function of (BLOW-IN) or (BLOW-OUT) for the decompression-panels. The protection devices protect the decompression-panels against impact from "X" and "Y" directions of misaligned luggage.
(5) Installation Description and Pressure Values
The rapid-decompression panels are installed in cut-outs in the linings of the cargo compartments. The sealing tape on the border makes a seal between the panel and the lining of the cargo compartment. The flame-retardant material fits tightly in the cut-outs of the linings and helps to seal the cargo compartment.
The rapid-decompression panels are installed from inside of the cargo compartment into the cut-outs as follows:
The rapid-decompression panels that are installed in the ceiling panels of the cargo compartments are kept free. A maximum height to load bulk cargo, is marked on the wall linings of the cargo compartment 2 in. (50.80 mm) below the ceiling.
The rapid-decompression panels that are installed in the FWD wall lining of the FWD cargo compartment are protected. A protection panel is installed on the inner side of the lining in front of the rapid-decompression panels. The panel is attached with brackets, to make a space between the two panels. When bulk cargo is transported, the protection panel keeps the rapid-decompression panels free.
The pressure difference-values between the cabin and the cargo compartment, necessary to release the decompression-panel from the lining, are:
The rapid-decompression panels are installed in cut-outs in the linings of the cargo compartments. The sealing tape on the border makes a seal between the panel and the lining of the cargo compartment. The flame-retardant material fits tightly in the cut-outs of the linings and helps to seal the cargo compartment.
The rapid-decompression panels are installed from inside of the cargo compartment into the cut-outs as follows:
- Push the panel into the cut-out.
- The shaped end of the latches adjust the position of the panel automatically to the center of the cut-out.
- The latches are moved into their housings to the open position.
- The panel is continually pushed over the full surface until the laminated-skin border is flush with the inner side of the linings.
- The latches snap back to the closed position and engage with the outer edges of the cut-outs.
The rapid-decompression panels that are installed in the ceiling panels of the cargo compartments are kept free. A maximum height to load bulk cargo, is marked on the wall linings of the cargo compartment 2 in. (50.80 mm) below the ceiling.
The rapid-decompression panels that are installed in the FWD wall lining of the FWD cargo compartment are protected. A protection panel is installed on the inner side of the lining in front of the rapid-decompression panels. The panel is attached with brackets, to make a space between the two panels. When bulk cargo is transported, the protection panel keeps the rapid-decompression panels free.
The pressure difference-values between the cabin and the cargo compartment, necessary to release the decompression-panel from the lining, are:
- 30 hPa (0.886 in.Hg) if a rapid decompression (BLOW-IN) in the cargo compartment occurs.
- 90 hPa (2.658 in.Hg) if a rapid decompression (BLOW-OUT) in the cabin occurs.
(6) Installation Description and Pressure Values
The rapid-decompression panels are installed in cut-outs in the linings of the cargo compartments. The sealing tape on the border makes a seal between the panel and the lining of the cargo compartment. The flame-retardant material fits tightly in the cut-outs of the linings and helps to seal the cargo compartment.
The rapid-decompression panels are installed from inside of the cargo compartment into the cut-outs as follows:
The rapid-decompression panels that are installed in the ceiling panels of the cargo compartments are kept free. A maximum height to load bulk cargo, is marked on the wall linings of the cargo compartment 2 in. (50.80 mm) below the ceiling.
The rapid-decompression panels that are installed in the FWD wall lining of the FWD cargo compartment are protected. A protection panel is installed on the inner side of the lining in front of the rapid-decompression panels. The panel is attached with brackets, to make a space between the two panels. When bulk cargo is transported, the protection panel keeps the rapid-decompression panels free.
The pressure difference-values between the cabin and the cargo compartment, necessary to release the decompression-panel from the lining, is:
The rapid-decompression panels are installed in cut-outs in the linings of the cargo compartments. The sealing tape on the border makes a seal between the panel and the lining of the cargo compartment. The flame-retardant material fits tightly in the cut-outs of the linings and helps to seal the cargo compartment.
The rapid-decompression panels are installed from inside of the cargo compartment into the cut-outs as follows:
- Push the panel into the cut-out.
- The shaped end of the latches adjust the position of the panel automatically to the center of the cut-out.
- The latches are moved into their housings to the open position.
- The panel is continually pushed over the full surface until the laminated-skin border is flush with the inner side of the linings.
- The latches snap back to the closed position and engage with the outer edges of the cut-outs.
The rapid-decompression panels that are installed in the ceiling panels of the cargo compartments are kept free. A maximum height to load bulk cargo, is marked on the wall linings of the cargo compartment 2 in. (50.80 mm) below the ceiling.
The rapid-decompression panels that are installed in the FWD wall lining of the FWD cargo compartment are protected. A protection panel is installed on the inner side of the lining in front of the rapid-decompression panels. The panel is attached with brackets, to make a space between the two panels. When bulk cargo is transported, the protection panel keeps the rapid-decompression panels free.
The pressure difference-values between the cabin and the cargo compartment, necessary to release the decompression-panel from the lining, is:
- 90 hPa (2.658 in.Hg) if a rapid decompression (BLOW-OUT) in the cabin occurs.
B. Dado Panels
The dado panel has a decorative panel with a cover assembly, and a support assembly. The decorative panel is seen from inboard and finishes the interior lining of the cabin from the upper sidewall-panels to the floor. It attaches the dado panel to the fuselage structure. The cover assembly is installed on the outboard side of the decorative panel.
The support assembly is installed on the outboard side of the decorative panel and attaches the dado panel to the floor. Decompression plates are installed in cut-outs in the back wall of the support assembly. The top edge of the plate is attached with half-hinges to the back wall and can move inboard and outboard. The bottom edge of the plate is held in the cut-out with stop-plates attached on both sides of the back wall. Insulation material is bonded on to the inboard side of the back wall and the inboard side of the decompression plates.
The pressure difference-value between the cabin and the cargo compartment, necessary to release the decompression panel in the support assembly, is 0.05 hPa (0.0014 in.Hg)
The dado panel has a decorative panel with a cover assembly, and a support assembly. The decorative panel is seen from inboard and finishes the interior lining of the cabin from the upper sidewall-panels to the floor. It attaches the dado panel to the fuselage structure. The cover assembly is installed on the outboard side of the decorative panel.
The support assembly is installed on the outboard side of the decorative panel and attaches the dado panel to the floor. Decompression plates are installed in cut-outs in the back wall of the support assembly. The top edge of the plate is attached with half-hinges to the back wall and can move inboard and outboard. The bottom edge of the plate is held in the cut-out with stop-plates attached on both sides of the back wall. Insulation material is bonded on to the inboard side of the back wall and the inboard side of the decompression plates.
The pressure difference-value between the cabin and the cargo compartment, necessary to release the decompression panel in the support assembly, is 0.05 hPa (0.0014 in.Hg)
C. Air Grills
The air grills are installed in some closed modules, for example stowages and lavatories.
The air grills are installed in some closed modules, for example stowages and lavatories.
D. Cockpit Door
The cockpit door is installed in the fixed partition between FR13 and FR14. It has an electrically operated locking mechanism. The locking mechanism is connected to a control unit, which is located on the overhead panel. Pressure sensing channels are located on the control unit, and measure sufficient fall in pressure to release the locking mechanism (rapid decompression). The sensing channels are independent from software and/or microprocessor failures.
The cockpit door is installed in the fixed partition between FR13 and FR14. It has an electrically operated locking mechanism. The locking mechanism is connected to a control unit, which is located on the overhead panel. Pressure sensing channels are located on the control unit, and measure sufficient fall in pressure to release the locking mechanism (rapid decompression). The sensing channels are independent from software and/or microprocessor failures.
5. Operation/Control and Indicating
A. Rapid-Decompression Panels
In usual operation the rapid-decompression panels form part of the cargo compartment linings.
If a rapid-decompression occurs in the cargo compartment, the higher air pressure pushes on the rapid-decompression panels. The shaped end of the latch pushes against the edge of the cut-out and causes the latch to move into the open position. The released rapid-decompression panels are blown rapidly into the cargo compartments (BLOW-IN). The higher air pressure can flow from the cabin to the cargo compartment.
If a rapid-decompression occurs in the cabin, the higher air pressure pushes on the rapid-decompression panels. The laminated-skin border folds away at the place where the honeycomb filling starts. The cuts in the corners help to accelerate this process. The panels are released and blown rapidly out from the cargo compartments (BLOW-OUT). The higher air pressure can flow from the cargo compartment to the cabin.
In usual operation the rapid-decompression panels form part of the cargo compartment linings.
If a rapid-decompression occurs in the cabin, the higher air pressure pushes on the rapid-decompression panels. The laminated-skin border folds away at the place where the honeycomb filling starts. The cuts in the corners help to accelerate this process. The panels are released and blown rapidly out from the cargo compartments (BLOW-OUT). The higher air pressure can flow from the cargo compartment to the cabin.
In usual operation the rapid-decompression panels form part of the cargo compartment linings.
If a rapid-decompression occurs in the cargo compartment, the higher air pressure pushes on the rapid-decompression panels. The shaped end of the latch pushes against the edge of the cut-out and causes the latch to move into the open position. The released rapid-decompression panels are blown rapidly into the cargo compartments (BLOW-IN). The higher air pressure can flow from the cabin to the cargo compartment.
If a rapid-decompression occurs in the cabin, the higher air pressure pushes on the rapid-decompression panels. The laminated-skin border folds away at the place where the honeycomb filling starts. The cuts in the corners help to accelerate this process. The panels are released and blown rapidly out from the cargo compartments (BLOW-OUT). The higher air pressure can flow from the cargo compartment to the cabin.
In usual operation the rapid-decompression panels form part of the cargo compartment linings.
If a rapid-decompression occurs in the cabin, the higher air pressure pushes on the rapid-decompression panels. The laminated-skin border folds away at the place where the honeycomb filling starts. The cuts in the corners help to accelerate this process. The panels are released and blown rapidly out from the cargo compartments (BLOW-OUT). The higher air pressure can flow from the cargo compartment to the cabin.
B. Dado Panels
In usual operation the dado panels let the air flow between the Cargo compartments and the cabin.
If a rapid-decompression occurs in the cargo compartment, the higher air pressure flows under the decorative panels. The covers channel the flow to the decompression plates and pushes them in the outboard direction. The higher air pressure can flow rapidly from the cabin to the cargo compartment.
If a rapid-decompression occurs in the cabin, the higher air pressure pushes the decompression plates in the inboard direction. The covers channel the flow under the decorative panel. The higher air pressure can flow rapidly from the cargo compartment to the cabin.
In usual operation the dado panels let the air flow between the Cargo compartments and the cabin.
If a rapid-decompression occurs in the cargo compartment, the higher air pressure flows under the decorative panels. The covers channel the flow to the decompression plates and pushes them in the outboard direction. The higher air pressure can flow rapidly from the cabin to the cargo compartment.
If a rapid-decompression occurs in the cabin, the higher air pressure pushes the decompression plates in the inboard direction. The covers channel the flow under the decorative panel. The higher air pressure can flow rapidly from the cargo compartment to the cabin.
C. Air Grills
In usual operation the air grills let the air move freely to and from the housings (stowages and lavatories).
If a rapid-decompression occurs, the air will flow rapidly through the air grills into the cabin.
In usual operation the air grills let the air move freely to and from the housings (stowages and lavatories).
If a rapid-decompression occurs, the air will flow rapidly through the air grills into the cabin.
D. Cockpit Door
In usual operation the cockpit door permits access to and from the cockpit to the cabin. During flight the cockpit door is closed and locked.
If a rapid-decompression in the cabin occurs, the cockpit door stays closed and locked. The higher air pressure in the cockpit flows through various ventilation paths, into the cabin and avionics compartment. The door frame, frame attachments and lavatory wall are strengthened to resist the initial high pressure, until the higher air pressure has decreased.
If a rapid-decompression occurs in the cockpit, the avionics compartment or the FWD Cargo compartment, the sensing channel measures the rapid fall in pressure. The control unit immediately releases (5 ms) the cockpit door locking mechanism. The higher air pressure, pushes the cockpit door open to the cockpit, and flows rapidly from the cabin into the cockpit.
In usual operation the cockpit door permits access to and from the cockpit to the cabin. During flight the cockpit door is closed and locked.
If a rapid-decompression in the cabin occurs, the cockpit door stays closed and locked. The higher air pressure in the cockpit flows through various ventilation paths, into the cabin and avionics compartment. The door frame, frame attachments and lavatory wall are strengthened to resist the initial high pressure, until the higher air pressure has decreased.
If a rapid-decompression occurs in the cockpit, the avionics compartment or the FWD Cargo compartment, the sensing channel measures the rapid fall in pressure. The control unit immediately releases (5 ms) the cockpit door locking mechanism. The higher air pressure, pushes the cockpit door open to the cockpit, and flows rapidly from the cabin into the cockpit.