Process and system for controlling the pressure in an aircraft cabin

1. A process for controlling the pressure in an aircraft cabin, comprising the steps of:

detecting the status of an aircraft door,

transmitting a signal indicative of the status of the aircraft door to a unit for controlling an avionics ventilation system and an air conditioning system, the avionics ventilation system cooling an avionics system of the aircraft during operational situations in which sufficiently high pressure prevails in the aircraft cabin and discharging cooling exhaust air from the aircraft cabin, the air conditioning system being adapted to cool the avionics system of the aircraft when less than sufficiently high pressure prevails in the air craft cabin, and

controlling the avionics ventilation system in dependence upon the signal indicative of the status of the aircraft door wherein a build-up of pressure in the aircraft cabin is prevented when the signal indicative of the status of the aircraft door indicates that the aircraft door is not fully closed and secured.

2. The process according to claim 1 , wherein the unit for controlling the avionics ventilation system controls an air outlet valve of the avionics ventilation system and a build-up of pressure in the aircraft cabin is prevented when the signal indicative of the status of the aircraft door indicates that the aircraft door is not fully closed and secured.

3. The process according to claim 1 , further comprising the steps of:

transmitting the signal indicative of the status of the aircraft door to a unit for controlling a cabin pressurization system, and

controlling the cabin pressurization system in dependence upon the signal indicative of the status of the aircraft door wherein a build-up of pressure in the aircraft cabin is prevented when the signal indicative of the status of the aircraft door indicates that the aircraft door is not fully closed and secured.

4. The process according to claim 3 , wherein the unit for controlling the cabin pressurization system controls at least one air outlet valve of the cabin pressurization system and a build-up of pressure in the aircraft cabin is prevented when the signal indicative of the status of the aircraft door indicates that the aircraft door is not fully closed and secured.

5. The process according to claim 3 , wherein the signal indicative of the status of the aircraft door is transmitted via dissimilar signal transmission devices to the unit for controlling the avionics ventilation system and to the unit for controlling the cabin pressurization system.

6. The process according to claim 1 , wherein the status of the aircraft door is detected by at least two mutually independent detection devices.

7. A system for controlling the pressure in an aircraft cabin, comprising:

at least one detection device for detecting the status of an aircraft door;

an avionics ventilation system cooling an avionics system of the aircraft during operational situations in which sufficiently high pressure prevails in the aircraft cabin discharging cooling exhaust air from the aircraft cabin,

an air conditioning system cooling the avionics system of the aircraft when less than sufficiently high pressure prevails in the air craft cabin; and

a transmission device for transmitting a signal indicative of the status of the aircraft door to a unit for controlling the avionics ventilation system,

wherein the unit for controlling the avionics ventilation system controls the avionics ventilation system in dependence upon the signal indicative of the status of the aircraft door such that a build-up of pressure in the aircraft cabin is prevented when the signal indicative of the status of the aircraft door indicates that the aircraft door is not fully closed and secured.

8. The system according to claim 7 , wherein the unit for controlling the avionics ventilation system controls an air outlet valve of the avionics ventilation system and a build-up of pressure in the aircraft cabin is prevented when the signal indicative of the status of the aircraft door indicates that the aircraft door is not fully closed and secured.

9. The system according to claim 7 , further comprising:

a transmission device for transmitting the signal indicative of the status of the aircraft door to a unit for controlling a cabin pressurization system, wherein the unit for controlling the cabin pressurization system controls the cabin pressurization system in dependence upon the signal indicative of the status of the aircraft door and a build-up of pressure in the aircraft cabin is prevented when the signal indicative of the status of the aircraft door indicates that the aircraft door is not fully closed and secured.

10. The system according to claim 9 , wherein the unit for controlling the cabin pressurization system controls at least one air outlet valve of the cabin pressurization system and a build-up of pressure in the aircraft cabin is prevented when the signal indicative of the status of the aircraft door indicates that the aircraft door is not fully closed and secured.

11. The system according to claim 9 , wherein the transmission device for transmitting the signal indicative of the status of the aircraft door to a unit for controlling an avionics ventilation system and the transmission device for transmitting the signal indicative of the status of the aircraft door to the unit for controlling a cabin pressurization system are dissimilar signal transmission devices.

12. The system according claim 7 , further comprising at least two mutually independent detection devices for detecting the status of the aircraft door.