Abstract: A navigational aid method of an aircraft, carried out by a flight management system, for comparing a reference trajectory of the aircraft subjected to a wind vector field with a new trajectory between the same starting and end points, respectively, the method comprises: determining the reference trajectory, determining the new trajectory, loading meteorological data, determining a directional surface, delimited by a directional closed curve, consisting of the new trajectory, from the starting point to the end point, closed by the opposite of the reference trajectory from the end point to the starting point, determining a wind curl on the basis of the wind vector field, determining a flow of the wind curl through the surface, a positive value of flow indicating that the new trajectory makes better use of the wind load, a negative value of flow indicating that the new trajectory makes less effective use of the wind load.

Abstract: A method for adapting an aircraft constant-gradient descent segment comprises: an acquisition step in which state variables characterizing the aircraft, environment variables characterizing the environment thereof and path variables characterizing the predicted path thereof at one of the initial and final points of the segment are acquired; a calculation step whereby a limit ground gradient for at least one performance criterion is calculated from the state variables, environment variables and path variables; a validity verification step checking the validity of the path initially predicted against the most restrictive limit ground gradient; and when the path initially predicted is not valid: a feasibility verification step checking the feasibility of a command to modify at least one state variable; if feasibility is verified, a prediction of executing the command; otherwise, a prediction of modifying one of the initial and final points of the segment with respect to constraints of the flight plan.

Abstract: This method for computing a conjugated airport navigation graph, from an initial airport navigation graph, is implemented by a computer. This method involves acquiring the initial graph including a plurality of navigation arcs, each including two end nodes, having at least one authorized navigation direction and being identified by its two end nodes. This method further involves determining a conjugated node for each navigation arc and for each authorized navigation direction of the arc, each conjugated node corresponding to a single authorized direction and representing the arc of the initial graph associated with the authorized direction. The conjugated graph is computed by connecting the conjugated nodes as a function of the connections between the arcs of the initial graph and the authorized directions. Two conjugated nodes connect to one another corresponding to two successive arcs of the initial graph and to a same authorized direction.

Abstract: A navigation aid method for an aircraft flying a reference trajectory between a point of departure and a point of arrival subject to a field of wind vectors comprises: decomposing the reference trajectory into a plurality of discrete waypoints Pi, loading meteorological data comprising the field of wind vectors, iterating the following steps N times, to generate an improved trajectory: for each waypoint Pi named current point, determining a reference plane, determining an orthonormal reference frame, determining a wind curl ((?W)Pi), determining a sign of the projection of the wind curl on axis zi ((?W)zi Pi), determining a direction of displacement from the current point Pi to a new current waypoint Pi?, determining a line of displacement, determining a displacement distance, determining the new current waypoint, determining a new trajectory, assigning the new waypoints Pi? determined in the preceding iteration to the waypoints Pi for the next iteration.

Abstract: A method for generating a taxi trajectory of an aircraft in an airport area includes the acquisition of a clearance including departure, arrival and intermediate elements of said area, the acquisition of a graph, and the determination, based on said graph, of entry and/or exit nodes for each element. It also includes the calculation, in the graph, of paths that are external to the elements and a path that is internal to each intermediate element, each external path connecting an exit node of one element to an entry node of the following element, each internal path connecting the entry node and exit node of said intermediate element, the paths calculated at first among the external and internal paths having a minimal cost; the calculation of a global path based on the internal path(s) and external paths and the generation of said taxi trajectory based on the global path.

Abstract: A navigational aid method of an aircraft, carried out by a flight management system, for comparing a reference trajectory of the aircraft subjected to a wind vector field with a new trajectory between the same starting and end points, respectively, the method comprises: determining the reference trajectory, determining the new trajectory, loading meteorological data, determining a directional surface, delimited by a directional closed curve, consisting of the new trajectory, from the starting point to the end point, closed by the opposite of the reference trajectory from the end point to the starting point, determining a wind curl on the basis of the wind vector field, determining a flow of the wind curl through the surface, a positive value of flow indicating that the new trajectory makes better use of the wind load, a negative value of flow indicating that the new trajectory makes less effective use of the wind load.

Abstract: A navigation aid method for an aircraft flying a reference trajectory between a point of departure and a point of arrival subject to a field of wind vectors comprises: decomposing the reference trajectory into a plurality of discrete waypoints Pi, loading meteorological data comprising the field of wind vectors, iterating the following steps N times, to generate an improved trajectory: for each waypoint Pi named current point, determining a reference plane, determining an orthonormal reference frame, determining a wind curl ((?W)Pi), determining a sign of the projection of the wind curl on axis zi ((?W)zi Pi), determining a direction of displacement from the current point Pi to a new current waypoint Pi?, determining a line of displacement, determining a displacement distance, determining the new current waypoint, determining a new trajectory, assigning the new waypoints Pi? determined in the preceding iteration to the waypoints Pi for the next iteration.

Abstract: This method for computing a conjugated airport navigation graph, from an initial airport navigation graph, is implemented by a computer. This method comprises acquiring the initial graph including a plurality of navigation arcs, each including two end nodes, having at least one authorized navigation direction and being identified by its two end nodes. This method further comprises determining a conjugated node for each navigation arc and for each authorized navigation direction of said arc, each conjugated node corresponding to a single authorized direction and representing said arc of the initial graph associated with said authorized direction; and computing the conjugated graph by connecting the conjugated nodes as a function of the connections between the arcs of the initial graph and the authorized directions, two conjugated nodes connected to one another corresponding to two successive arcs of the initial graph and to a same authorized direction.

Abstract: A method for adapting an aircraft constant-gradient descent segment comprises: an acquisition step in which state variables characterizing the aircraft, environment variables characterizing the environment thereof and path variables characterizing the predicted path thereof at one of the initial and final points of the segment are acquired; a calculation step whereby a limit ground gradient for at least one performance criterion is calculated from the state variables, environment variables and path variables; a validity verification step checking the validity of the path initially predicted against the most restrictive limit ground gradient; and when the path initially predicted is not valid: a feasibility verification step checking the feasibility of a command to modify at least one state variable; if feasibility is verified, a prediction of executing the command; otherwise, a prediction of modifying one of the initial and final points of the segment with respect to constraints of the flight plan.

Abstract: This building method concerns building of at least one aircraft guideline in an airport navigation network. The navigation network includes a plurality of polygons and is associated with an airport area including taxiways, each guideline connecting two distinct sides of a corresponding polygon, the navigation network being configured to be stored in a memory of a computer system. The method is implemented by a computer and includes the following steps creating nodes at each intersection between an existing guideline and a side of a corresponding polygon, or at the middle of a side shared by two polygons when no guideline is secant with said side, detecting at least one pair of nodes not connected by a guideline, computing, for each detected pair of nodes, a guideline in the form of a polynomial curve, and storing the computed guidelines in the memory of the computer system.