Terrain Avoidance System for Transport Aircraft

• US 20080288169A1
• Filed: 10/31/2006
• Published: 11/20/2008
• Est. Priority Date: 11/10/2005
• Status: Active Grant

• Current Assignee: Thales SA
• Original Assignee: Thales SA
• Inventors: Marty, Nicolas, Meunier, Hugues
• Granted Patent: US 8,280,622 B2
• Time in Patent Office: Days
• US Class Current: 701/301
• CPC Class Codes: G01C 21/005 with correlation of navigation data from several sources, e.g. map or contour matching G01C21/30 takes precedence
• CPC Class Codes: G01C 5/005 altimeters for aircraft G01C5/02, G01C5/06 take precedence
• CPC Class Codes: G05D 1/106 Change initiated in response to external conditions, e.g. avoidance of elevated terrain or of no-fly zones
• CPC Class Codes: G08G 5/0086 for monitoring terrain radar or analogous systems specially adapted for terrain avoidance G01S13/935
• CPC Class Codes: G08G 5/045 Navigation or guidance aids, e.g. determination of anti-collision manoeuvers radar or analogous systems specially adapted for anti-collision between aircraft G01S13/933

Abstract

This system accompanies the “Avoid terrain” type alarms indicating to the pilot that he has passed the limit-point of success of a standard vertical avoidance maneuver either with complementary indications such as the azimuth sectors suitable for a disengagement maneuver or a predefined disengagement path, or an automatic engagement of a predefined avoidance path. To determine the limit-point, it monitors a penetration of a model of the terrain being flown over into a first protection volume (1) linked to the aircraft and configured so as to model a standard vertical avoidance maneuver path executed without delay, said path being predefined according to the type of aircraft, its weight and its inertia, and, for the determination of the disengagement azimuth sectors, an analysis of the penetrations of the model of the terrain being flown over into a second protection volume (2) with large azimuth aperture, linked to the aircraft and configured so as to contain the limit-point protection volume (1) and, for the various azimuths covered, paths of a composite maneuver beginning with change-of-heading maneuvers with which to reach the azimuth concerned and continuing with the standard terrain vertical avoidance maneuver, said paths being, over their parts corresponding to the standard vertical avoidance maneuver, predefined according to the type of aircraft, its weight and its inertia.

Claims

1. A system onboard an aircraft, for preventing collisions with the terrain likening a risk of collision with the terrain after a predetermined forecast delay to the penetration of a cartographic representation of the terrain being flown over, stored in a database accessible to the aircraft, into a protection volume linked to the aircraft located relative to the terrain being flown over by means of onboard locating equipment, oriented in the direction of progress of the aircraft and configured so as to model a standard terrain vertical avoidance maneuver path engaged over the forecast delay based on the path followed by the aircraft predicted from flight information delivered by aircraft flight equipment, assuming that the aircraft maintains its current speed vector with the same trend, if it is in the process of changing, said system comprising:

means for detecting the limit-point of success of a standard terrain vertical avoidance maneuver likening the crossing of this limit-point by the aircraft to the penetration of the terrain into a protection volume linked to the aircraft and configured so as to model a standard vertical avoidance maneuver path executed without notable delay, said path being predefined according to the aircraft type,

means for determining azimuth disengagement sectors, either side of the direction of progress of the aircraft, suitable for the success of a standard terrain vertical avoidance maneuver likening the azimuth disengagement sectors to the azimuth sectors (a, b, c) free of penetration of the terrain into a protection volume with large azimuth aperture, linked to the aircraft and configured so as to contain the limit-point protection volume and, for the various azimuths covered, paths of a composite maneuver beginning with change-of-heading maneuvers with which to reach the azimuth concerned and continuing with the standard terrain vertical avoidance maneuver, said paths being, over their parts corresponding to the standard vertical avoidance maneuver, predefined according to the aircraft type,

means for signaling the crossing of the limit-point of success of the standard terrain vertical avoidance maneuver, and

means for signaling azimuth disengagement sectors.

2. The system as claimed in claim 1, wherein a predefined path corresponding to a standard vertical avoidance maneuver is also dependent on the weight of the aircraft.

3. The system as claimed in claim 1, wherein a predefined path corresponding to a standard vertical avoidance maneuver is also dependent on the inertia of the aircraft.

4. The system as claimed in claim 1, wherein a predefined path corresponding to a standard vertical avoidance maneuver is also dependent on the aircraft configuration of the moment.

5. The system as claimed in claim 1, further comprising means for signaling a composite terrain avoidance maneuver with minimal change of heading.

6. The system as claimed in claim 1, further comprising means for guiding the crew of the aircraft in executing a composite terrain avoidance maneuver.

7. The system as claimed in claim 1, further comprising means for automatically executing a composite terrain avoidance maneuver directly affecting the aircraft flight equipment.

8. The system as claimed in claim 1, further comprising means for alerting to a medium-term risk of collision with the terrain involving, to be resolved, a change of path of the aircraft, on the part of the crew, likening a collision with the terrain to the penetration of the terrain into an alert protection volume linked to the aircraft modeling a predefined standard vertical avoidance maneuver path engaged in the medium term.

9. The system as claimed in claim 1, further comprising means for raising an alarm concerning a short-term risk of collision with the terrain likening a short-term collision with the terrain to the penetration of the terrain into an alarm protection volume linked to the aircraft modeling a predefined standard vertical avoidance maneuver path engaged in the short term.

10. The system as claimed in claim 8, with alert and/or alarm means concerning the medium- and/or short-term risk of collision with the terrain, wherein the protection volume linked to the aircraft to determine disengagement sectors and the protection volumes linked to the aircraft for alert and alarm model predefined standard avoidance maneuver paths of different types, the predefined path modeled in the protection volume to determine disengagement sectors having a climb gradient greater than the predefined paths modeled in the alert and alarm protection volumes.

11. The system as claimed in claim 9, with alert and/or alarm means concerning the medium- and/or short-term risk of collision with the terrain, wherein the protection volume linked to the aircraft to determine disengagement sectors and the protection volumes linked to the aircraft for alert and alarm model predefined standard avoidance maneuver paths of different types, the predefined path modeled in the protection volume to determine disengagement sectors having a climb gradient greater than the predefined paths modeled in the alert and alarm protection volumes.