METHOD AND DEVICE FOR AIRCRAFT, FOR AVOIDING COLLISION WITH THE TERRAIN

• US 20100042273A1
• Filed: 08/29/2007
• Published: 02/18/2010
• Est. Priority Date: 09/12/2006
• Status: Active Grant

• Current Assignee: Thales SA
• Original Assignee: Thales SA
• Inventors: Marty, Nicolas, Meunier, Hugues, Percier, Julia
• Granted Patent: US 8,897,935 B2
• Time in Patent Office: Days
• US Class Current: 701/9
• CPC Class Codes: G01C 23/005 Flight directors indicating arrangements specially adapted for rotary gyroscopes G01C19/32
• CPC Class Codes: G05D 1/0607 specially adapted for aircraft
• CPC Class Codes: G05D 1/0676 specially adapted for landing
• 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 alarms of TAWS type and in particular the alarms of “Avoid terrain” type indicating to the pilot that he has passed the limit point of success of a standard vertical avoidance maneuver, indications (32, 33) of free-travel distances in azimuth sectors suited to a clearance maneuver and one or more recommended relief avoidance maneuvers (A, B), both lateral and vertical. For the determination of the limit point, it monitors the penetration of a model of the terrain being flown over into a first protection volume (1) linked to the aircraft and configured in such a way as to model a standard vertical avoidance maneuver trajectory executed without notable delay. For the determination of the azimuth sectors open to a clearance maneuver, it analyzes the penetrations of the model of terrain being flown over in a second protection volume with large azimuth aperture, linked to the aircraft and configured in such a way as to contain the limit point protection volume (1). To evaluate the free-travel distances, it searches for limit points of effectiveness of a standard vertical avoidance maneuver, on arbitrary distancing trajectories in the azimuth sectors open to the clearance maneuvers. Based on the determination of these free-travel distances, the system determines the limit instant of manual initiation by the pilot or automatic initiation of an avoidance trajectory and determines the optimum route alteration to be initiated prior to the avoidance maneuver.

Claims

1. A system for preventing collisions with the terrain:

detecting means for detecting the risks of collision with the terrain after a predetermined forecasting delay, by likening them to the penetration of a topographic representation of the terrain being flown over stored in a database accessible to the aircraft, in a protection volume linked to the aircraft located relative to the terrain being flown over by means of an onboard locating equipment item, oriented in the direction in which the aircraft is moving and configured in such a way as to model a standard vertical terrain avoidance maneuver trajectory undertaken over the forecasting delay from the trajectory followed by the aircraft predicted from flight information delivered by flight equipment of the aircraft,

determining means for determining, on the trajectory followed by the aircraft, a possible limit point for success of a standard vertical terrain avoidance maneuver, by likening the crossing by the aircraft of this limit point to the penetration of the terrain into a protection volume linked to the aircraft and configured in such a way as to model a standard vertical avoidance maneuver trajectory executed without delay, said trajectory being predefined as a function of the type of the aircraft, and

indications means for giving indications on the azimuth clearance sectors, around the direction in which the aircraft is moving, suitable for the success of a standard vertical terrain avoidance maneuver, by likening the azimuth clearance sectors to the azimuth sectors free of penetration of the terrain into a protection volume with large azimuth aperture, linked to the aircraft and configured in such a way as to contain the limit point protection volume and, for the different azimuths covered, trajectories of a compound maneuver beginning with change-of-heading maneuvers making it possible to reach the azimuth concerned and continuing with the standard vertical terrain avoidance maneuver,

said system being characterized in that it comprises;

means for estimating free-travel distance to estimate, in each azimuth clearance sector, on a straight distancing trajectory with constant gradient and over a distance corresponding to several minutes of flight, a free-travel distance free of potential conflict with the terrain, and

means for signaling azimuth clearance sectors with their free-travel distances.

2. The system as claimed in claim 1, wherein the means for estimating free-travel distance determine, on the distancing trajectories, possible limit points for success of a standard vertical avoidance maneuver marking the limit of a free-travel distance.

3. The system as claimed in claim 1, wherein the means for estimating free-travel distance determine, on the distancing trajectories, possible points of initiation of a vertical avoidance maneuver with arbitrary slope, less than that of a standard vertical avoidance maneuver, said initiation points being taken as the limit of an immediate free-travel distance.

4. The system as claimed in claim 1, wherein the distancing trajectory concerned in a clearance sector is a horizontal straight trajectory.

5. The system as claimed in claim 1, wherein the distancing trajectory concerned in a clearance sector is a straight trajectory reproducing the slope of the current trajectory of the aircraft.

6. The system as claimed in claim 1, characterized wherein the distancing trajectory concerned in a clearance sector is a climbing straight trajectory.

7. The system as claimed in claim 1, wherein the compound maneuver used to generate the protection volume for the determination of the clearance sectors begins with a change-of-heading maneuver consisting in a turn in a horizontal plane.

8. The system as claimed in claim 1, wherein the compound maneuver used to generate the protection volume for the determination of the clearance sectors begins with a change-of-heading maneuver consisting in a climbing turn.

9. The system as claimed in claim 2, wherein the standard vertical avoidance maneuver concerned for the determination of the free-travel distances in the clearance sectors has its trajectory predefined as a function of the type of the aircraft and of its current climb capabilities.

10. The system as claimed in claim 2, wherein the standard vertical avoidance maneuver concerned for the determination of the free-travel distances in the clearance sectors has its trajectory predefined as a function of the type of the aircraft and of its current configuration.

11. The system as claimed in claim 1, further comprising means for selecting at least one compound terrain avoidance maneuver minimizing the change of route and any conflicts in the medium term with the terrain.

12. The system as claimed in claim 11, further comprising means for displaying the selected compound maneuver or maneuvers.

13. The system as claimed in claim 11, further comprising means for guiding the crew of the aircraft in the execution of a compound terrain avoidance maneuver.

14. The system as claimed in claim 11, further comprising means for automatically executing a compound terrain avoidance maneuver acting directly on the flight equipment of the aircraft.

15. The system as claimed in claim 1, further comprising means for warning of the risk of collision in the medium term with the terrain, likening a collision with the terrain to the penetration of the terrain into a warning protection volume linked to the aircraft that models a predefined standard vertical avoidance maneuver trajectory undertaken in the medium term.

16. The system as claimed in claim 1, further comprising short-term terrain collision risk alarm means likening a collision in the short term with the terrain to the penetration of the terrain into an alarm protection volume linked to the aircraft that models a predefined standard vertical avoidance maneuver undertaken in the short term.

17. The system as claimed in claim 1, further comprising medium- and short-term terrain collision risk warning and alarm means implementing a protection volume for the determination of the clearance sectors and of the warning and alarm protection volumes modeling predefined standard avoidance maneuver trajectories of different types, the predefined trajectory modeled in the protection volume for the determination of the clearance sectors having a climb slope greater than the predefined trajectories modeled in the warning and alarm protection volumes.