DOC AIRBUS | AMM A320FMAIN STRUCTURE - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
1. General
Main Structure - General ** ON A/C NOT FOR ALL
Main Structure - General ** ON A/C NOT FOR ALL
Main Structure - General ** ON A/C NOT FOR ALL
Main Structure - General ** ON A/C NOT FOR ALL
The main structure of the outer wing is the wing box, which tapers from wing root (RIB1) to wing tip (RIB27). It also makes the integral fuel tank and the vent surge tank (Ref. AMM D/O 28-00-00-00). Access into the wing box is through the access panels in the bottom skin.
** ON A/C NOT FOR ALL Main Structure - General ** ON A/C NOT FOR ALL Main Structure - General ** ON A/C NOT FOR ALL Main Structure - General ** ON A/C NOT FOR ALL Main Structure - General ** ON A/C NOT FOR ALL 2. Component Location
The wing box is made of:
Attached to the wing box are:
Attached to the wing box are:
** ON A/C NOT FOR ALL The wing box is made of:
- the wing spars (front and rear)
- the ribs
- the top and bottom skin-panels
- the top and bottom stringers
- the wing-root joint.
Attached to the wing box are:
- the fixed partitions (slat cans) (Ref. AMM D/O 57-24-00-00)
- the attachment fittings (Ref. AMM D/O 57-26-00-00)
- the access panels (Ref. AMM D/O 57-27-00-00)
- the jacking point and the drip fence (Ref. AMM D/O 57-29-00-00).
- the wing spars (front and rear)
- the ribs
- the top and bottom skin-panels
- the top and bottom stringers
- the wing-root joint.
Attached to the wing box are:
- the fixed partitions (slat cans) (Ref. AMM D/O 57-24-00-00)
- the attachment fittings (Ref. AMM D/O 57-26-00-00)
- the access panels (Ref. AMM D/O 57-27-00-00)
- the jacking point, the drip fence and the air dam (Ref. AMM D/O 57-29-00-00).
3. Description
A. Wing Box
The wing box has a full fuel tank and a vent surge tank.
The sealed inter-spar ribs disconnect these tanks. The primary sealing of the tanks is made with the mechanical attachment of the structure, with a fillet of sealant applied at the tank edges.
Each outer wing fuel-tank also has a closed area, between RIB1 and RIB2, which is a collector cell for the main fuel pumps (Ref. AMM D/O 28-21-00-00).
On each wing there are two unvented dry bays which are inboard of the engine and immediately behind the front spar. The largest dry bay is between RIB5 and RIB6 and the smallest dry bay is between RIB6 and RIB6B. Each dry bay has a drain hole in the lower skin which, if there is a fuel leakage:
There are closing panels in the fuel tank, at the rear of the dry bays. The closing panels are made of carbon fiber with a honeycomb core. They are attached with nuts and bolts to machined aluminum-alloy posts which are installed on the ribs. There is also a top plate land attached to a stringer and a bottom sealing angle. Brackets add strength to the two areas.
Sealing blocks and seals prevent fuel leakage into the dry bays between the stringers and the top and bottom skin panels.
Two holes in the front spar give access to the dry bays. They are closed with closing plates.
The wing box has a full fuel tank and a vent surge tank.
The sealed inter-spar ribs disconnect these tanks. The primary sealing of the tanks is made with the mechanical attachment of the structure, with a fillet of sealant applied at the tank edges.
Each outer wing fuel-tank also has a closed area, between RIB1 and RIB2, which is a collector cell for the main fuel pumps (Ref. AMM D/O 28-21-00-00).
The wing box has a full fuel tank and a vent surge tank.
The sealed inter-spar ribs disconnect these tanks. The primary sealing of the tanks is made with the mechanical attachment of the structure, with a fillet of sealant applied at the tank edges.
Each outer wing fuel-tank also has a closed area, between RIB1 and RIB2, which is a collector cell for the main fuel pumps (Ref. AMM D/O 28-21-00-00).
On each wing there are two unvented dry bays which are inboard of the engine and immediately behind the front spar. The largest dry bay is between RIB5 and RIB6 and the smallest dry bay is between RIB6 and RIB7. Each dry bay has a drain hole in the lower skin which, if there is a fuel leakage:
There are inboard and outboard doors in the fuel tank at the rear of the dry bays. The inboard and outboard doors are made of carbon fiber with a honeycomb core. They are attached with nuts and bolts to the machined aluminum-alloy posts which are installed on the ribs. There are inboard and outboard diaphragm closeouts attached to a stringer in the fuel tank area and inboard and outboard diaphragms between the ribs. Brackets add strength to the two areas.
Seal cleats prevent fuel leakage into the dry bays between the stringers and the top and bottom skin panels.
Two holes in the front spar give access to the dry bays. They are closed with closing plates.
The wing box has a full fuel tank and a vent surge tank.
The sealed inter-spar ribs disconnect these tanks. The primary sealing of the tanks is made with the mechanical attachment of the structure, with a fillet of sealant applied at the tank edges.
Each outer wing fuel-tank also has a closed area, between RIB1 and RIB2, which is a collector cell for the main fuel pumps (Ref. AMM D/O 28-21-00-00).
On each wing there are two unvented dry bays which are inboard of the engine and immediately behind the front spar. The largest dry bay is between RIB5 and RIB6 and the smallest dry bay is between RIB6 and RIB6B. Each dry bay has a drain hole in the lower skin which, if there is a fuel leakage:
- Prevents large quantities of fuel in the dry bay, and
- Helps to detect internal leaks in a short time.
There are closing panels in the fuel tank, at the rear of the dry bays. The closing panels are made of carbon fiber with a honeycomb core. They are attached with nuts and bolts to machined aluminum-alloy posts which are installed on the ribs. There is also a top plate land attached to a stringer and a bottom sealing angle. Brackets add strength to the two areas.
Sealing blocks and seals prevent fuel leakage into the dry bays between the stringers and the top and bottom skin panels.
Two holes in the front spar give access to the dry bays. They are closed with closing plates.
The wing box has a full fuel tank and a vent surge tank.
The sealed inter-spar ribs disconnect these tanks. The primary sealing of the tanks is made with the mechanical attachment of the structure, with a fillet of sealant applied at the tank edges.
Each outer wing fuel-tank also has a closed area, between RIB1 and RIB2, which is a collector cell for the main fuel pumps (Ref. AMM D/O 28-21-00-00).
The wing box has a full fuel tank and a vent surge tank.
The sealed inter-spar ribs disconnect these tanks. The primary sealing of the tanks is made with the mechanical attachment of the structure, with a fillet of sealant applied at the tank edges.
Each outer wing fuel-tank also has a closed area, between RIB1 and RIB2, which is a collector cell for the main fuel pumps (Ref. AMM D/O 28-21-00-00).
On each wing there are two unvented dry bays which are inboard of the engine and immediately behind the front spar. The largest dry bay is between RIB5 and RIB6 and the smallest dry bay is between RIB6 and RIB7. Each dry bay has a drain hole in the lower skin which, if there is a fuel leakage:
- Prevents large quantities of fuel in the dry bay, and
- Helps to detect internal leaks in a short time.
There are inboard and outboard doors in the fuel tank at the rear of the dry bays. The inboard and outboard doors are made of carbon fiber with a honeycomb core. They are attached with nuts and bolts to the machined aluminum-alloy posts which are installed on the ribs. There are inboard and outboard diaphragm closeouts attached to a stringer in the fuel tank area and inboard and outboard diaphragms between the ribs. Brackets add strength to the two areas.
Seal cleats prevent fuel leakage into the dry bays between the stringers and the top and bottom skin panels.
Two holes in the front spar give access to the dry bays. They are closed with closing plates.
B. Wing Spars
The spars are machined from aluminum alloy. They give strength to the wing box. The front and the rear spars extend from RIB1 to RIB27.
The spars are machined from aluminum alloy. They give strength to the wing box. The front and the rear spars extend from RIB1 to RIB27.
(1) Front Spar
The front spar is made as a single piece, to include:
The front spar is made as a single piece, to include:
- a horizontal stiffener (crack retarder)
- vertical web stiffeners
- a reinforced hole at each slat track position
- reinforced holes for the components of the fuel system (Ref. AMM D/O 28-00-00-00)
- an opening for the build door between STA0/RIB1 and STA700/RIB2, for the installation of the outer wing to the centre box.
(2) Rear Spar
The rear spar is made from three parts. These are the inner, the middle and the outer sections. Joint plates connect these sections together to make a continuous structure. The joints are made at RIB6 and RIB22. The rear spar is machined to include:
The rear spar is made from three parts. These are the inner, the middle and the outer sections. Joint plates connect these sections together to make a continuous structure. The joints are made at RIB6 and RIB22. The rear spar is machined to include:
- a horizontal stiffener (crack retarder)
- vertical web stiffeners
- reinforced holes for the components of the fuel system (Ref. AMM D/O 28-00-00-00)
- a reinforced jacking point at RIB9.
C. Ribs
Each wingbox of each outer wing has 27 ribs made from aluminum alloy. Each rib is continuous between the front and rear spars. The center-wing to outer-wing joint is made at STA0/RIB1, which closes the center wing box. RIB22 and RIB27 make the other lateral boundaries of the fuel and vent tanks.
At RIB2 thru RIB9, and at RIB12 and RIB19, the ribs have double flanges for the attachment of the skin panels. The remaining ribs have single flanges.
Cleats attach the top stringers to the ribs. Ribs 12 and 19 are reinforced to provide attachment points for the forward flap-track-beam attachment. The holes in the ribs (for access and fuel pipes) are also reinforced.
Rib 2 has two manhole doors (Ref. AMM D/O 57-27-00-00), which are kept closed with clamps. Maintenance access is given at RIB5 and the hole is closed with a load-carrying door.
There are 27 ribs, machined from aluminum alloy, installed in the wingbox of each outer wing. Each rib is continuous between the front and rear spars. The centre-wing to outer-wing joint is made at STA0/RIB1, which closes the centre wing box. Ribs RIB22 and RIB27 make the other lateral boundaries of the fuel and vent tanks.
At RIB2 thru RIB9, and at RIB12 and RIB19, the ribs have double flanges for attachment of skin panels. The remainder have single flanges.
Cleats attach the top stringers to the ribs. Ribs 12 and 19 are reinforced to provide attachment points for the forward flap-track-beam attachment. The holes in the ribs, for access and fuel pipes, are reinforced.
Rib 2 has two hinged access doors (Ref. AMM D/O 57-27-00-00), which are kept closed with springs. Access for build is provided in RIB5 and the hole is closed with a load-carrying door.
Top and Bottom Skin Panels ** ON A/C NOT FOR ALL
Top and bottom skin panel, showing vent duct location and construction ** ON A/C NOT FOR ALL
Each wingbox of each outer wing has 27 ribs made from aluminum alloy. Each rib is continuous between the front and rear spars. The center-wing to outer-wing joint is made at STA0/RIB1, which closes the center wing box. RIB22 and RIB27 make the other lateral boundaries of the fuel and vent tanks.
At RIB2 thru RIB9, and at RIB12 and RIB19, the ribs have double flanges for the attachment of the skin panels. The remaining ribs have single flanges.
Cleats attach the top stringers to the ribs. Ribs 12 and 19 are reinforced to provide attachment points for the forward flap-track-beam attachment. The holes in the ribs (for access and fuel pipes) are also reinforced.
Rib 2 has two manhole doors (Ref. AMM D/O 57-27-00-00), which are kept closed with clamps. Maintenance access is given at RIB5 and the hole is closed with a load-carrying door.
There are 27 ribs, machined from aluminum alloy, installed in the wingbox of each outer wing. Each rib is continuous between the front and rear spars. The centre-wing to outer-wing joint is made at STA0/RIB1, which closes the centre wing box. Ribs RIB22 and RIB27 make the other lateral boundaries of the fuel and vent tanks.
At RIB2 thru RIB9, and at RIB12 and RIB19, the ribs have double flanges for attachment of skin panels. The remainder have single flanges.
Cleats attach the top stringers to the ribs. Ribs 12 and 19 are reinforced to provide attachment points for the forward flap-track-beam attachment. The holes in the ribs, for access and fuel pipes, are reinforced.
Rib 2 has two hinged access doors (Ref. AMM D/O 57-27-00-00), which are kept closed with springs. Access for build is provided in RIB5 and the hole is closed with a load-carrying door.
Top and Bottom Skin Panels ** ON A/C NOT FOR ALL Top and bottom skin panel, showing vent duct location and construction ** ON A/C NOT FOR ALL D. Skin Panels and Stringers
The top and the bottom surfaces of the wing box are made of skin panels machined from aluminum alloy. There are two panels on the top skin and three panels on the bottom skin. To increase their strength, the panels have stringers machined from aluminum alloy extrusions. Joint straps, made of aluminum alloy, connect the panels. Interference bolts attach the panels to the ribs and the spars.
The top and the bottom skin panels continue a short distance forward of the front spar. The leading edge structure attaches to these projections.
Outboard of the MLG support rib, the skin panels continue a short distance aft of the rear spar. The trailing edge structure and the trailing edge devices attach to these projections.
There are 21 access panels, in the bottom skin panels, which give access into the wing box. The bottom skin panels are reinforced in the area around the holes for the fuel pumps (Ref. AMM D/O 28-21-00-00).
There is one opening in the top skin between RIB22 and RIB23, for the overwing refuel adaptor.
Reinforcing plates are attached to the outer face of the bottom skin panels, and to the inner face of the top skin panels to add strength at the pylon attachments.
A reinforcing plate, machined from aluminum alloy, is attached to the outer surface of the wing-box bottom skin. This adds strength to the skin panels at the MLG attachments.
The top and the bottom surfaces of the wing box are made of skin panels machined from aluminum alloy. There are two panels on the top skin and three panels on the bottom skin. To increase their strength, the panels have stringers machined from aluminum alloy extrusions. Joint straps, made of aluminum alloy, connect the panels. Interference bolts attach the panels to the ribs and the spars.
The top and the bottom skin panels continue a short distance forward of the front spar. The leading edge structure attaches to these projections.
Outboard of the MLG support rib, the skin panels continue a short distance aft of the rear spar. The trailing edge structure and the trailing edge devices attach to these projections.
There are 21 access panels, in the bottom skin panels, which give access into the wing box. The bottom skin panels are reinforced in the area around the holes for the fuel pumps (Ref. AMM D/O 28-21-00-00).
There is one opening in the top skin between RIB22 and RIB23, for the overwing refuel adaptor.
Reinforcing plates are attached to the outer face of the bottom skin panels, and to the inner face of the top skin panels to add strength at the pylon attachments.
A reinforcing plate, machined from aluminum alloy, is attached to the outer surface of the wing-box bottom skin. This adds strength to the skin panels at the MLG attachments.
E. Wing Root Joint
The wing box of the outer wing is attached to the wing box of the center wing at RIB1. Top and bottom fittings of aluminum alloy connect the spar webs of the center wing to those of the outer wing. A cruciform member is used to keep the continuity of the top skin across the joint. Bolts attach the top skin panels of the center wing and the outer wing to the cruciform member.
Crown fittings made of aluminum alloy keep the continuity of the top skin stringers across the joint. The crown fittings are attached to the outboard vertical face of the cruciform member (RIB1). Bolts attach the stringers to the crown fittings.
The continuity of the bottom skin across the joint is kept through a triform member. There is a strap machined from aluminum alloy across the joint. Interference bolts attach the strap and the bottom skin panels to the triform member. The bottom skin stringers are not continuous across the joint. End loads are absorbed by the stringer-to-skin joint.
The wing box of the outer wing is attached to the wing box of the center wing at RIB1. Top and bottom fittings of aluminum alloy connect the spar webs of the center wing to those of the outer wing. A cruciform member is used to keep the continuity of the top skin across the joint. Bolts attach the top skin panels of the center wing and the outer wing to the cruciform member.
Crown fittings made of aluminum alloy keep the continuity of the top skin stringers across the joint. The crown fittings are attached to the outboard vertical face of the cruciform member (RIB1). Bolts attach the stringers to the crown fittings.
The continuity of the bottom skin across the joint is kept through a triform member. There is a strap machined from aluminum alloy across the joint. Interference bolts attach the strap and the bottom skin panels to the triform member. The bottom skin stringers are not continuous across the joint. End loads are absorbed by the stringer-to-skin joint.
F. Dry Bay(s)
On each wing there are two unvented dry bays which are inboard of the engine and immediately behind the front spar. Each dry bay has a drain hole in the lower skin which, if there is a fuel leakage:
Sealing blocks and seals prevent fuel leakage into the dry bays between the stringers and the top and bottom skin panels.
Two holes in the front spar give access to the dry bays. They are closed with closing plates.
On each wing there are two unvented dry bays which are inboard of the engine and immediately behind the front spar. Each dry bay has a drain hole in the lower skin which, if there is a fuel leakage:
There are inboard and outboard doors in the fuel tank at the rear of the dry bays. The inboard and outboard doors are made of carbon fiber with a honeycomb core. They are attached with nuts and bolts to the machined aluminum-alloy posts, which are installed on the ribs. There are inboard and outboard diaphragm closeouts attached to a stringer in the fuel tank area and inboard and outboard diaphragms between the ribs. Brackets add strength to the two areas.
Seal cleats prevent fuel leakage into the dry bays between the stringers and the top and bottom skin panels.
Two holes in the front spar give access to the dry bays. They are closed with closing plates.
On each wing there are two unvented dry bays which are inboard of the engine and immediately behind the front spar. Each dry bay has a drain hole in the lower skin which, if there is a fuel leakage:
- Prevents large quantities of fuel in the dry bay, and
- Helps to detect internal leaks in a short time.
Sealing blocks and seals prevent fuel leakage into the dry bays between the stringers and the top and bottom skin panels.
Two holes in the front spar give access to the dry bays. They are closed with closing plates.
On each wing there are two unvented dry bays which are inboard of the engine and immediately behind the front spar. Each dry bay has a drain hole in the lower skin which, if there is a fuel leakage:
- Prevents large quantities of fuel in the dry bay, and
- Helps to detect internal leaks in a short time.
There are inboard and outboard doors in the fuel tank at the rear of the dry bays. The inboard and outboard doors are made of carbon fiber with a honeycomb core. They are attached with nuts and bolts to the machined aluminum-alloy posts, which are installed on the ribs. There are inboard and outboard diaphragm closeouts attached to a stringer in the fuel tank area and inboard and outboard diaphragms between the ribs. Brackets add strength to the two areas.
Seal cleats prevent fuel leakage into the dry bays between the stringers and the top and bottom skin panels.
Two holes in the front spar give access to the dry bays. They are closed with closing plates.