DOC AIRBUS | AMM A320FDOOR - OVERPRESSURE RELEASE, APU COMPARTMENT - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
1. General
The overpressure release door is installed in the upper left side of the APU compartment between FR83 and FR84.
It prevents damage to the fuselage tailcone if there is a sudden increase of pressure in the APU compartment.
If a sudden increase of pressure occurs (e.g. a leak at a bleed-air line) the door opens, it closes automatically when the pressure decreases. A drive lever keeps the opening of the door to a limit.
A hinge connects the door to the fuselage structure. When the door is closed it is level with the fuselage contour. Tension springs keep it in the closed position.
** ON A/C NOT FOR ALL The overpressure release door is installed in the upper left side of the APU compartment between FR83 and FR84.
It prevents damage to the fuselage tailcone if there is a sudden increase of pressure in the APU compartment.
If a sudden increase of pressure occurs (e.g. a leak at a bleed-air line) the door opens, it closes automatically when the pressure decreases. A drive lever keeps the opening of the door to a limit.
A hinge connects the door to the fuselage structure. When the door is closed it is level with the fuselage contour. Tension springs keep it in the closed position.
2. Component Description
The door is made of aluminum alloy. It has seven louvered openings which are for ventilation.
Screws attach the hinge to the inside of the door. Rivets connects the hinge on the fuselage structure at FR83.
A bonding strap is attached to the hinge and to the fuselage structure.
The tension springs are installed between a bracket on FR84 and an attachment fitting on the door. The bracket and the attachment fitting are made from aluminum alloy.
A slot in the drive lever lets the door move out and in.
The tension springs are loaded to 11.7 +-0.5 daN or -+0.5 daN (26.3026 +-1.1240 lbf or -+1.1240 lbf). A nut (installed at the end of the tension springs) lets you adjust the tension in the spring.
** ON A/C NOT FOR ALL The door is made of aluminum alloy. It has seven louvered openings which are for ventilation.
Overpressure Release Door - Component LocationScrews attach the hinge to the inside of the door. Rivets connects the hinge on the fuselage structure at FR83.
A bonding strap is attached to the hinge and to the fuselage structure.
The tension springs are installed between a bracket on FR84 and an attachment fitting on the door. The bracket and the attachment fitting are made from aluminum alloy.
A slot in the drive lever lets the door move out and in.
The tension springs are loaded to 11.7 +-0.5 daN or -+0.5 daN (26.3026 +-1.1240 lbf or -+1.1240 lbf). A nut (installed at the end of the tension springs) lets you adjust the tension in the spring.
3. Operation
If there is an overpressure in the APU compartment a force is applied to the overpressure release door. When the force is more than 11.7 daN (26.3026 lbf) the door opens and the overpressure is released into the open area.
The door closes automatically when the pressure decreases.
If there is an overpressure in the APU compartment a force is applied to the overpressure release door. When the force is more than 11.7 daN (26.3026 lbf) the door opens and the overpressure is released into the open area.
The door closes automatically when the pressure decreases.