Method and system for emergency ventilating and pressurizing an aircraft cabin

Patent metadata

Field	Value
Publication number	US-9802709-B2
Application number	US-201314100158-A
Country	US
Kind code	B2
Filing date	Dec 9, 2013
Priority date	Dec 10, 2012
Publication date	Oct 31, 2017
Grant date	Oct 31, 2017

Abstract

A method for emergency ventilating and pressurizing an aircraft cabin comprises determining a cabin pressure within the aircraft cabin and determining an ambient pressure in an aircraft environment. Descent of the aircraft is initiated when the cabin pressure falls below a predetermined threshold value. A supply of ambient air from the aircraft environment into the aircraft cabin is initiated, when, during descent of the aircraft, a differential pressure between the cabin pressure and the ambient pressure falls below a first calculated threshold value. The supply of ambient air into the aircraft cabin and an operation of an air outflow valve of a cabin pressurization system of the aircraft are controlled such that a flow of ambient air into the aircraft cabin corresponds to at least a predetermined minimum value and the differential pressure between the cabin pressure and the ambient pressure does not fall below a second calculated threshold value.

First claim

The invention claimed is:

1. A method for emergency ventilating and pressurizing an aircraft cabin, comprising the steps:
determining a cabin pressure prevailing within the aircraft cabin,
determining an ambient pressure prevailing in an aircraft environment,
initiating descent of the aircraft when the cabin pressure falls below a predetermined threshold value,
initiating a supply of ambient air from the aircraft environment into the aircraft cabin, when, during descent of the aircraft, a differential pressure between the cabin pressure and the ambient pressure falls below a first calculated threshold value, and
feedback controlling the supply of ambient air from the aircraft environment into the aircraft cabin based on a feedback signal indicative of a flow of ambient air from the aircraft environment into the aircraft cabin by adjusting a flow cross-section of an emergency ram inlet or of a valve allowing the supply of ambient air into the aircraft cabin and controlling an operation of an air outflow valve of a cabin pressurization system of the aircraft, such that a flow of ambient air from the aircraft environment into the aircraft cabin corresponds to at least a predetermined minimum value and the differential pressure between the cabin pressure and the ambient pressure does not fall below a second calculated threshold value.

2. The method of claim 1 , wherein the supply of ambient air from the aircraft environment into the aircraft cabin and the operation of the air outflow valve of the cabin pressurization system of the aircraft are controlled such that a re-pressurization rate within the aircraft cabin is lower than an ambient pressure increase rate during descent of the aircraft.

3. The method of claim 1 , further comprising the step:
terminating descent of the aircraft and initiating cruising of the aircraft at a constant altitude when the differential pressure between the cabin pressure and the ambient pressure reaches the second calculated threshold value.

4. The method of claim 1 , further including a step of cruising the aircraft at a constant altitude, wherein, when the aircraft cruises at a constant altitude, the supply of ambient air from the aircraft environment into the aircraft cabin and operation of the air outflow valve of the cabin pressurization system of the aircraft are controlled such that the cabin pressure is higher than or equal to an ambient pressure prevailing in the aircraft environment at an altitude of 10,000 feet (3048 m).

5. The method of claim 1 , wherein the supply of ambient air from the aircraft environment into the aircraft cabin is initiated in dependence on a signal provided from a manually actuatable input device.

6. The method of claim 1 , further comprising at least one of the steps:
determining a number of passengers present within the aircraft cabin,
determining an ambient temperature, and
determining a cabin temperature,
wherein a constant cruising altitude of the aircraft and the second calculated threshold value of the differential pressure between the cabin pressure and the ambient pressure, which is maintained while the aircraft is cruising at the constant cruising altitude, are determined in dependence on at least one of the number of passenger preset within the aircraft cabin, the ambient temperature, and the cabin temperature.

7. The method of claim 1 , further comprising the steps:
determining an operational status of an aircraft air conditioning system,
calculating a leakage effective area based on the cabin pressure, the ambient pressure and the operational status of the aircraft air conditioning system, and
determining a maximum constant cruising altitude of the aircraft in dependence on the calculated leakage effective area and the second calculated threshold value of the differential pressure between the cabin pressure and the ambient pressure.

8. The method of claim 1 , further comprising the steps:
determining a position of the air outflow valve of the cabin pressurization system of the aircraft, and
confirming that the flow of ambient air from the aircraft environment into the aircraft cabin corresponds to at least the predetermined minimum value based on the position of the air outflow valve of the cabin pressurization system of the aircraft.

9. A system for emergency ventilating and pressurizing an aircraft cabin, comprising:
a device for determining a cabin pressure prevailing within the aircraft cabin,
a device for determining an ambient pressure prevailing in an aircraft environment, and
an electrical control device, the control device being adapted to:
initiate descent of the aircraft, when the cabin pressure falls below a predetermined threshold value,
initiate a supply of ambient air from the aircraft environment into the aircraft cabin, when, during descent of the aircraft, a differential pressure between the cabin pressure and the ambient pressure falls below a first calculated threshold value, and
feedback-control the supply of ambient air from the aircraft environment into the aircraft cabin based on a feedback signal indicative of a flow of ambient air from the aircraft environment into the aircraft cabin by adjusting a flow cross-section of an emergency ram inlet or of a valve allowing the supply of ambient air into the aircraft cabin and controlling an operation of an air outflow valve of a cabin pressurization system of the aircraft, such that a flow of ambient air from the aircraft environment into the aircraft cabin corresponds to at least a predetermined minimum value and the differential pressure between the cabin pressure and the ambient pressure does not fall below a second calculated threshold value.

10. The system of claim 9 , wherein the control device is adapted to control the supply of ambient air from the aircraft environment into the aircraft cabin and the operation of the air outflow valve of the cabin pressurization system of the aircraft such that a re-pressurization rate within the aircraft cabin is lower than an ambient pressure increase rate during descent of the aircraft.

11. The system of claim 9 , wherein the control device further is adapted to:
terminate descent of the aircraft and initiate cruising of the aircraft at a constant altitude when the differential pressure between the cabin pressure and the ambient pressure reaches the second calculated threshold value, wherein the control device in particular is adapted to control the supply of ambient air from the aircraft environment into the aircraft cabin and the operation of the air outflow valve of the cabin pressurization system of the aircraft such that the cabin pressure is higher than or equal to an ambient pressure prevailing in the aircraft environment at an altitude of 10,000 feet (3048 m), when the aircraft cruises at a constant altitude.

12. The system of claim 9 , wherein the control device is adapted to initiate the supply of ambient air from the aircraft environment into the aircraft cabin automatically or in dependence on a signal provided from a manually actuatable input device.

13. A system for emergency ventilating and pressurizing an aircraft cabin, comprising:
a device for determining a cabin pressure prevailing within the aircraft cabin,
a device for determining an ambient pressure prevailing in an aircraft environment, and
an electrical control device, the control device being adapted to:
initiate descent of the aircraft, when the cabin pressure falls below a predetermined threshold value,
initiate a supply of ambient air from the aircraft environment into the aircraft cabin, when, during descent of the aircraft, a differential pressure between the cabin

Assignees

• Airbus Operations Gmbh

Inventors

• Huart David
• Hadewig Hanjo

Classifications

• B64D2013/064

  comprising more than one system, e.g. dual systems · CPC title

• B64D2013/0618

  with arrangements for reducing or managing bleed air, using another air source, e.g. ram air · CPC title

• B64D13/04 Primary

  Automatic control of pressure · CPC title

• Y02T50/56

  Cross-Sectional Technologies · mapped topic

• B64D13/02

  the air being pressurised · CPC title