DOC AIRBUS | AMM A320FBULK CARGO COMPARTMENT DOOR - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
1. General
The bulk cargo-compartment door (bulk door) is installed on the lower right side of the fuselage between FR60 and FR62. The bulk door is a manually operated door and gives access to the bulk cargo compartment. It opens to the inner side and a hook arrester safeties it in the fully open position.
The size of the bulk door is 1200 x 940 mm (47.24 x 37.00 in. ) and its weight is 32.2 kg (71.0 lbs.).
** ON A/C NOT FOR ALL The bulk cargo-compartment door (bulk door) is installed on the lower right side of the fuselage between FR60 and FR62. The bulk door is a manually operated door and gives access to the bulk cargo compartment. It opens to the inner side and a hook arrester safeties it in the fully open position.
The size of the bulk door is 1200 x 940 mm (47.24 x 37.00 in. ) and its weight is 32.2 kg (71.0 lbs.).
2. Component Location
** ON A/C NOT FOR ALL 
Bulk Cargo-Compartment Door - Component Location| ------------------------------------------------------------------------------- |
| FIN I FUNCTIONAL DESIGNATION I PANELIZONEIACCESS I ATA |
| I I I I DOOR I REF. |
| ------------------------------------------------------------------------------- |
| DOOR STRUCTURE 827 52-33-00 |
| DOOR SUSPENSION 827 52-33-12 |
| LINING AND INSULATION 827 52-33-13 |
| DOOR SEAL 827 52-33-18 |
| LOCKING MECHANISM 827 52-33-21 |
| STOP ASSEMBLIES 827 52-33-31 |
| BALANCE MECHANISM 827 52-33-41 |
3. System Description
The Bulk door is attached with two hinge arms on the related hinge fittings of the fuselage. It has a balance mechanism to decrease the force necessary to open the Bulk door to the inner side. This mechanism keeps the Bulk door open so that it can not fall down when it is not fully opened. The door handle mechanism operates the locking shaft which locks or releases the Bulk door. The locking shaft also operates the latch assy which safeties the Bulk door in its fully open position.
A proximity switch of the door warning system monitors the locked condition of the Bulk door. This switch sends a signal to the Electronic Centralized Aircraft Monitor (ECAM) System which gives a warning in the cockpit.
** ON A/C NOT FOR ALL The Bulk door is attached with two hinge arms on the related hinge fittings of the fuselage. It has a balance mechanism to decrease the force necessary to open the Bulk door to the inner side. This mechanism keeps the Bulk door open so that it can not fall down when it is not fully opened. The door handle mechanism operates the locking shaft which locks or releases the Bulk door. The locking shaft also operates the latch assy which safeties the Bulk door in its fully open position.
A proximity switch of the door warning system monitors the locked condition of the Bulk door. This switch sends a signal to the Electronic Centralized Aircraft Monitor (ECAM) System which gives a warning in the cockpit.
4. Component Description
A. Door Structure
The primary structure of the Bulk door includes horizontal beams and vertical spars which are made of aluminum alloy. The inner and outer skins, also made of aluminum alloy, contain the primary structure. All components are riveted together to give the Bulk door its rigidity. All rivets and joints in the skins and door structure are sealed to give a pressure-tight outer surface.
The outer skin has a cut-out to rivet the housing of the door handle mechanism to the structure. This housing has a recess for the external door handle to get a continuous surface with the outer skin.
A liquid drain device is installed in the lower beam between the seal and outer skin. On the ground, the drain opens to let the liquid out. During the flight, the drain device closes because of the differential pressure.
The primary structure of the Bulk door includes horizontal beams and vertical spars which are made of aluminum alloy. The inner and outer skins, also made of aluminum alloy, contain the primary structure. All components are riveted together to give the Bulk door its rigidity. All rivets and joints in the skins and door structure are sealed to give a pressure-tight outer surface.
The outer skin has a cut-out to rivet the housing of the door handle mechanism to the structure. This housing has a recess for the external door handle to get a continuous surface with the outer skin.
A liquid drain device is installed in the lower beam between the seal and outer skin. On the ground, the drain opens to let the liquid out. During the flight, the drain device closes because of the differential pressure.
B. Door Suspension
The suspension of the Bulk door includes two hinge fittings and two hinge arms with their dampers. The hinge fittings are riveted to the vertical spars of the door structure. The hinge arms are attached to the hinge fittings and connected to the fuselage door frame. These connections are made with pivot pins which are safetied in position with a screw and a tab washer. The dampers decrease the shockloads of the hinge fittings which can occur during the pressurization of the fuselage.
The suspension of the Bulk door includes two hinge fittings and two hinge arms with their dampers. The hinge fittings are riveted to the vertical spars of the door structure. The hinge arms are attached to the hinge fittings and connected to the fuselage door frame. These connections are made with pivot pins which are safetied in position with a screw and a tab washer. The dampers decrease the shockloads of the hinge fittings which can occur during the pressurization of the fuselage.
C. Lining and Insulation
Special insulation panels with different thicknesses are installed in the gaps between the horizontal beams and the vertical spars (referred to as interspaces) for the heat protection. They are made of polyethylene foam and attached with their self-adhesive sides on the inner face of the outer skin. The thinner panels are only in the inter spaces where the movable components of the locking and balance mechanism are installed.
A special lining for the fire protection is installed on the inner skin of th e Bulk door. This lining is in three parts which are attached with VELCRO tapes on their positions.
Special insulation panels with different thicknesses are installed in the gaps between the horizontal beams and the vertical spars (referred to as interspaces) for the heat protection. They are made of polyethylene foam and attached with their self-adhesive sides on the inner face of the outer skin. The thinner panels are only in the inter spaces where the movable components of the locking and balance mechanism are installed.
A special lining for the fire protection is installed on the inner skin of th e Bulk door. This lining is in three parts which are attached with VELCRO tapes on their positions.
D. Door Seal
The door seal, made of special rubber hose, is installed in the retainers, riveted on the door structure. When the Bulk door is closed, the door seal is pressed on a bulb section of the fuselage door frame. The cabin pressure inflates the door seal to make a pressure-tight interface.
The door seal, made of special rubber hose, is installed in the retainers, riveted on the door structure. When the Bulk door is closed, the door seal is pressed on a bulb section of the fuselage door frame. The cabin pressure inflates the door seal to make a pressure-tight interface.
E. Locking Mechanism
The locking mechanism is installed in the lower section of the Bulk door. Its primary components are the door handle mechanism, the locking shaft and the latch assy.
The door handle mechanism has the lever assy and external door handles which are installed in the handle housing. The external door handle contains a lock mechanism which keeps the handle in the recess of its housing. The spring moves the external door handle from the recess if the mechanism is released. The internal actuator pin of the extended handle engages with the slot of the lever assy. Thus, the external door handle can operate the locking shaft only when it is out of the recess.
A detention rod is installed between the lever assy and the door structure. It makes sure that the lever assy is always in the overcenter position.
The locking mechanism includes the locking shaft with the related shaft lever and the main lever and the barrel locks. The two barrel locks engage with the latch spigots to lock the Bulk door in the closed position. The latch spigots are on the door frame of the fuselage. The push-rod connects the lever assy with the main lever to transmit the movement of the door handle to the locking shaft.
To safety the Bulk door in the open position, the hook of the latch assy engages with the hook arrester. The spring unit connects the hook with the shaft lever so that the movement of the locking shaft operates the hook.
The two barrel locks engage with the latch spigots and hold the Bulk door in the closed position. The latch spigots are attached to the door frame of the fuselage. A detention rod is installed between the lever assy and the door structure. It makes sure that the lever assy is always in the overcenter position.
The locking mechanism is installed in the lower section of the Bulk door. Its primary components are the door handle mechanism, the locking shaft and the latch assy.
The door handle mechanism has the lever assy and external door handles which are installed in the handle housing. The external door handle contains a lock mechanism which keeps the handle in the recess of its housing. The spring moves the external door handle from the recess if the mechanism is released. The internal actuator pin of the extended handle engages with the slot of the lever assy. Thus, the external door handle can operate the locking shaft only when it is out of the recess.
A detention rod is installed between the lever assy and the door structure. It makes sure that the lever assy is always in the overcenter position.
The locking mechanism includes the locking shaft with the related shaft lever and the main lever and the barrel locks. The two barrel locks engage with the latch spigots to lock the Bulk door in the closed position. The latch spigots are on the door frame of the fuselage. The push-rod connects the lever assy with the main lever to transmit the movement of the door handle to the locking shaft.
To safety the Bulk door in the open position, the hook of the latch assy engages with the hook arrester. The spring unit connects the hook with the shaft lever so that the movement of the locking shaft operates the hook.
The two barrel locks engage with the latch spigots and hold the Bulk door in the closed position. The latch spigots are attached to the door frame of the fuselage. A detention rod is installed between the lever assy and the door structure. It makes sure that the lever assy is always in the overcenter position.
F. Balance Mechanism
The balance mechanism includes the torsion bar, the pre-load unit and the connection rod. All components are installed in the upper section of the Bulk door.
The connection rod is attached between the forward lever of the torsion bar and the fuselage structure. The connection rod causes a tension of the torsion bar during the movement of the Bulk door in the open position.
The preload unit includes the flange bearing assy, the clamping sleeve and the clamping screw. A pivot pin connects the rear lever of the torsion bar with the clamping sleeve. The clamping screw sets the torsion bar in the preload condition.
The balance mechanism includes the torsion bar, the pre-load unit and the connection rod. All components are installed in the upper section of the Bulk door.
The connection rod is attached between the forward lever of the torsion bar and the fuselage structure. The connection rod causes a tension of the torsion bar during the movement of the Bulk door in the open position.
The preload unit includes the flange bearing assy, the clamping sleeve and the clamping screw. A pivot pin connects the rear lever of the torsion bar with the clamping sleeve. The clamping screw sets the torsion bar in the preload condition.
G. Stop Assemblies
The stop assemblies include the adjustable stops and the stop fittings. The adjustable stops are attached to each beam end of the Bulk door. The stops touch the stop fittings when the fuselage is pressurized during the flight. The stop fittings are attached to the door frame of the fuselage.
The stop assemblies include the adjustable stops and the stop fittings. The adjustable stops are attached to each beam end of the Bulk door. The stops touch the stop fittings when the fuselage is pressurized during the flight. The stop fittings are attached to the door frame of the fuselage.
A. Open Mode
To open the Bulk door from the external side, press the button of the external door handle. This releases the handle lock mechanism and the external door handle moves from the recess. This position makes sure that the external door handle can operate the locking shaft.
To release the closed Bulk door, put the external door handle to its "OPEN" position. This movement causes the lever assy to operate the pushrod which turns the locking shaft. Thus, the front and rear barrel locks disengage from their latch spigots and the Bulk door is released.
To release the Bulk door from the inner side, use a spanner with a width across the flats of 28.5749 mm (1.1250 in.) to operated the lever assy directly.
The disengaged rear barrel lock does not operate the spring-loaded lever assy of the latch spigot. This causes its related target to operate the proximity switch 50WV which sends a signal to the ECAM system. Thus, the ECAM system gives a warning in the cockpit to tell that the Bulk door is not locked.
Move the Bulk door inboard until the latch spigots on the fuselage frame come in view. The balance mechanism holds the Bulk door in this position.
Put the external door handle in the "LOCKED" position again. This moves the locking shaft which operates the spring rod to safety the overcenter position of the hook. After this operation, push the external door handle into its recess again to prevent possible damage during the loading .
Then move the Bulk door manually inboards until the hook engages with the hook arrester of the fuselage crossbeam. This operation safeties the Bulk door in its fully open position.
To open the Bulk door from the external side, press the button of the external door handle. This releases the handle lock mechanism and the external door handle moves from the recess. This position makes sure that the external door handle can operate the locking shaft.
To release the closed Bulk door, put the external door handle to its "OPEN" position. This movement causes the lever assy to operate the pushrod which turns the locking shaft. Thus, the front and rear barrel locks disengage from their latch spigots and the Bulk door is released.
To release the Bulk door from the inner side, use a spanner with a width across the flats of 28.5749 mm (1.1250 in.) to operated the lever assy directly.
The disengaged rear barrel lock does not operate the spring-loaded lever assy of the latch spigot. This causes its related target to operate the proximity switch 50WV which sends a signal to the ECAM system. Thus, the ECAM system gives a warning in the cockpit to tell that the Bulk door is not locked.
Move the Bulk door inboard until the latch spigots on the fuselage frame come in view. The balance mechanism holds the Bulk door in this position.
Put the external door handle in the "LOCKED" position again. This moves the locking shaft which operates the spring rod to safety the overcenter position of the hook. After this operation, push the external door handle into its recess again to prevent possible damage during the loading .
Then move the Bulk door manually inboards until the hook engages with the hook arrester of the fuselage crossbeam. This operation safeties the Bulk door in its fully open position.
B. Close Mode
To close the Bulk door, press the button of the external door handle. This releases the handle lock mechanism and the external door handle moves from the recess. This position makes sure that the external door handle can operate the locking shaft.
To release the opened Bulk door, put the external door handle to its "OPEN" position. This movement causes the lever assy to operate the push rod which turns the locking shaft. Thus, the spring unit operates the hook which disengages from the hook arrester. The balance mechanism prevents that the Bulk door falls down if it is not safetied.
Pull the Bulk door down into the door opening until it is in line with the fuselage contour. Put the external door handle to the "LOCKED" position. This operation moves the locking shaft so that the front and rear barrel locks engage with their latch spigots. During this movement, the rear barrel lock operates the lever assy and its related target operates the proximity switch 50WV. This operation cancels the warning of the ECAM system in the cockpit.
Push the external door handle into its recess when the Bulk door is closed and locked.
To close the Bulk door, press the button of the external door handle. This releases the handle lock mechanism and the external door handle moves from the recess. This position makes sure that the external door handle can operate the locking shaft.
To release the opened Bulk door, put the external door handle to its "OPEN" position. This movement causes the lever assy to operate the push rod which turns the locking shaft. Thus, the spring unit operates the hook which disengages from the hook arrester. The balance mechanism prevents that the Bulk door falls down if it is not safetied.
Pull the Bulk door down into the door opening until it is in line with the fuselage contour. Put the external door handle to the "LOCKED" position. This operation moves the locking shaft so that the front and rear barrel locks engage with their latch spigots. During this movement, the rear barrel lock operates the lever assy and its related target operates the proximity switch 50WV. This operation cancels the warning of the ECAM system in the cockpit.
Push the external door handle into its recess when the Bulk door is closed and locked.