Landing aid device, especially for anti-ground-collision alert vetoing

• US 6,317,663 B1
• Filed: 09/24/1999
• Issued: 11/13/2001
• Est. Priority Date: 09/24/1998
• Status: Expired due to Term

• Current Assignee: Thomson Csf Detexis
• Original Assignee: Thomson Csf Detexis
• Inventors: Meunier, Hugues, Roger, Christophe, Lepere, Gerard, Gauge, Vincent, Leonardi, Eric
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): PIPALA, EDWARD J
• Application Number:
  US09/405,234
• Time in Patent Office: 781 Days
• Field of Search: 701/1, 701/3-5, 701/8, 701/9, 701/14, 701/16, 701/300, 701/301, 701/302, 731/78.R, 731/78.T, 340/945, 340/948, 340/951, 340/961, 340/970-972, 340/974, 244/114.R, 244/183-186
• US Class Current: 701/16
• CPC Class Codes: B64D 45/04 Landing aids; Safety measures to prevent collision with earth's surface
• CPC Class Codes: G01C 5/005 altimeters for aircraft G01C5/02, G01C5/06 take precedence
• CPC Class Codes: G05D 1/0676 specially adapted for landing
• CPC Class Codes: G08G 5/025 Navigation or guidance aids radar or analogous systems specially adapted for landing purposes G01S13/913

Abstract

A landing aid device comprises processing means, which receive aircraft path data, and data regarding the position of at least one runway towards which the aircraft is steering. These processing means comprise calculation means which supply a state signal, comprising at least one condition which is dependent on the path data and on the runway data, this function being chosen so as to express the fact that the path of the aircraft converges towards the runway.

Claims

1. Landing aid device, comprising processing means, which receive on the one hand aircraft path data, and on the other hand data regarding the position of at least one runway, wherein the processing means comprises:

calculation means able to supply a state signal comprising at least one condition which is a function of the path data and of the runway data, this function being chosen so as to express the fact that the path of the aircraft converges towards the runway;

first means capable of generating an alert in the event of the imminence of an aircraft/ground collision; and

second means capable of vetoing said alert in the presence of a veto signal, wherein this veto signal is derived from the state signal.

2. Device according to claim 1, characterized in that the calculation means are organized so as to define a volume which possesses a chosen outline, positioned in a chosen manner with respect to said runway, and in that the state signal comprises a so-called static condition, pertaining to the current position of the aircraft to this volume.

3. Device according to claim 1, characterized in that the state signal comprises a so-called dynamic condition, pertaining to the convergence of a predicted path of the aircraft towards said runway, according to a chosen criterion.

4. Device according to claim 1, characterized in that the runway is defined by a representation stored in memory.

5. Device according to claim 1, characterized in that the calculation means are organized so as to define the said volume with the aid of a horizontal approach sector, by projection on a plane containing the said runway, and in that the static condition comprises a horizontal static subcondition, representative of the coincidence of the current position of the aircraft with this horizontal approach sector.

6. Device according to claim 5, characterized in that the data regarding the position of the runway comprise a representation of a reference point, in the guise of nominal point of grounding of the landing path, together with the orientation of the runway axis in the landing direction;

in that the calculation means are organized so as to define two auxiliary points, situated at chosen distances either side of the reference point, on a straight line transverse to said identified runway and passing through the reference point; and

in that the horizontal approach sector is delimited laterally by two lines which depart respectively from said two auxiliary points and diverge on either side of the runway axis, receding from the runway, up to a maximum distance with respect to the reference point.

7. Device according to claim 6, characterized in that the calculation means are organized so as to calculate the angles between the axis of the runway and the straight lines joining the current position of the aircraft to the two auxiliary points, respectively, whilst the horizontal approach sector comprises points for which the smaller of the two angles is less than an angle/distance limit curve, part of which curve is decreasing with the reduction in the distance from the aircraft to the reference point.

8. Device according to claim 7, characterized in that the decrease in the limit curve goes from around 40°

for a distance of around 4000 meters to around 8°

for a distance of around 900 meters.

9. Device according to claim 6, characterized in that the horizontal approach sector furthermore comprises a substantially rectangular zone, one side of which is defined by said two auxiliary points, and the opposite side of which passes through a point situated a chosen distance downstream of the reference point on the runway axis.

10. Device according to claim 3, wherein the dynamic condition comprises a horizontal dynamic subcondition, representative of the fact that a series of position, projected in the plane containing said runway, of the predicted path of the aircraft, satisfies a criterion of convergence towards the runway.

11. Device according to claim 10, characterized in that the calculation means are organized so as to calculate the angle between the horizontal projection of the approach heading of the aircraft and the axis of the runway, so as to determine two boundaries which can be likened to a part at least of the said horizontal approach sector, as well as a margin, derived from the distance between the horizontal position of the aircraft and the more remote of the two boundaries, except if the aircraft is receding from both boundaries simultaneously;

and in that the horizontal dynamic subcondition is satisfied when the said approach heading is less than a heading/margin limit curve, an intermediate part of which limit curve is decreasing with the reduction in the said margin.

12. Device according to claim 11, characterized in that the approach heading is defined on the basis of a direction vector departing from the current position of the aircraft together with a measurement and a direction which are derived from the instantaneous horizontal speed of the aircraft, and from the angle which this vector forms with the axis of the runway.

13. Device according to claim 2, characterized in that the static condition comprises a vertical static subcondition, representative of the presence of the aircraft inside a vertical approach sector.

14. Device according to claim 13, characterized in that the calculation means are organized so as to define two other auxiliary points, one situated on the runway axis a chosen distance upstream of the reference point, the other a chosen distance downstream of the reference point and at a chosen height, and in that the vertical approach sector comprises the points whose distance upstream of the reference point is less than a threshold, and which lie between a straight line of slope which decreases downstream and passes through the first point and a straight line of slope which decreases downstream and passes through the second point, the second slope being greater than the first.

15. Device according to claim 3, characterized in that the dynamic condition comprises a vertical dynamic subcondition, representative of the fact that positions of the predicted path of the aircraft satisfy a criterion of convergence to the said identified runway, in a vertical plane intersecting the said runway.

16. Device according to claim 13, characterized in that the dynamic condition comprises a vertical dynamic subcondition, representative of the fact that positions of the predicted path of the aircraft satisfy a criterion of convergence to the said identified runway, in a vertical plane intersecting the said runway;

in that the calculation means are organized so as to establish the vertical speed of the aircraft towards the ground, and the residual height of the aircraft above the bottom boundary of the vertical approach sector; and

in that the vertical dynamic subcondition is satisfied when the said residual height is greater than a height/speed limit curve, an intermediate part of which limit curve is decreasing with the reduction in speed towards the ground.

17. Device according to claim 1, characterized in that the state signal comprises a condition regarding the configuration of the aircraft.

18. Device according to claim 17, characterized in that the condition regarding the configuration of the aircraft comprises a condition pertaining to the lowering of the landing gear, and at least one condition relating to the flaps.

19. A landing aid device, comprising:

an alert generator capable of generating an alert in the event of the imminence of an aircraft/ground collision;

a calculator, which receives on the one hand aircraft path data, and on the other hand data regarding the position of at least one runway, and which is able to supply a state signal indicating at least one condition in which the path of the aircraft converges towards the runway; and

an alert inhibitor, responsive to said state signal, for inhibiting said alert generator and preventing generation of said alert.