Abstract: A method for assisting low-altitude navigation of an aircraft equipped with a system suited to determine a flight-plan ground trajectory based on intermediate points P at an altitude alt(P), and the aircraft's performance. The method includes the following steps: for each point P, calculating a safe altitude, to obtain a point Psafe, calculating a safe profile formed from segments joining the points Psafe, extracting summits S from among the points Psafe, determining the aircraft's weight at these points S, for each point S, determining the maximum climb slope MaxClimbFPA and the maximum descent slope MaxDescFPA, defining two performance segments which have slopes MaxClimbFPA and MaxDescFPA on either side of the point S and calculating a performance profile formed from performance segments.

Abstract: The present invention relates to a method of decoupling the mode of automatic following of the lateral profile and the mode of automatic following of the vertical profile of an automatic guidance system of an aircraft (A) flying on a reference trajectory (T). The mode of automatic following of the vertical profile is not disengaged immediately on disengaging the mode of automatic following of the lateral profile. After disengaging the mode of automatic following of the lateral profile, the mode of automatic following of the vertical profile is disengaged automatically only if at least one criterion of lateral separation between the current or short-term position of the aircraft and the lateral profile corresponding to the reference trajectory is satisfied, having regard to the position error.

Abstract: The present invention relates to a method for automatically preparing an update of audio communication frequencies between aircraft and ATC stations on the ground, a method making it possible to reduce the communication time associated with the necessary frequency changes between control sectors, therefore limiting the frequency space requirement, and reducing the workload due to the manipulations and control of these frequency changes, both for the air traffic controllers and for the aircraft crews, and wherein the flight plan or the current trajectory followed by the aircraft is dynamically coupled with the geometry information of the control sectors overflown by the aircraft and that, thereby knowing the intersection points of the flight plan with the sector limits, the frequency changes and sector name are prepared before each change of sector, while warning the pilot of their imminence.

Abstract: The general field of the invention is that of systems for aiding the guidance of an aircraft on an airport. The system according to the invention comprises means for determining at least one element of the topology of the airport in relation to the position of the aircraft for selecting. Selecting means are provided by the pilot of the aircraft for the element. Generating means are provided to generate at least one guidance or safety set-point using the topological element. Presenting means are provided for the element or the associated set-point on a man-machine interface to the pilot of the aircraft.

Abstract: The invention relates to a method for calculating an approach trajectory of an aircraft (200) to an airport The aircraft is slaveable in terms of trajectory, thrust and/or speed. The aircraft is able to advance at reduced engine revs. The airport has a runway The approach trajectory terminates in an impact point (205) on the runway and has a high-altitude descent segment (217) and an intermediate geometric segment (207), to which the aircraft is slaved in terms of trajectory and speed. A step of calculating a final approach segment (208) at reduced engine revs and a landing segment is performed with a greater thrust than the reduced revs so as to prepare a possible go-around (209), to which the aircraft is slaved in terms of thrust and speed.

Abstract: A method of optimizing a flight plan of an aircraft used in a flight management system of an aircraft is disclosed. This method makes it possible to constrain the real cost index of the mission executed to the optimal cost index CIopt predetermined by the aircraft operator, by acting on objectives ETAopt and EFOBopt of values of ETA and of EFOB to be achieved. Objectives are linked to this optimal cost index, in order to make the system return from a cost index CIm to the optimal cost index CIopt, while taking account of various constraints imposed by the ATC or the CTFM. Both constraints mext influence the cost index and constraints which limit the field of possible solutions.

Abstract: This method relates to the system of ATM air traffic management with cooperative aircraft provided with a flight management computer FMS, that are linked by a data transmission system ATN to the control authority and that have presented a flight plan to the control authority. It consists in communicating to the control authority via the ATN link, the projections SPWPi,j onto the flight plan LTFP of pseudo-waypoints PWPi,j introduced by the flight management computer FMS during lateral (between two segments of the flight plan) and/or vertical (between two breaks in slope) softened transitions performed by the aircraft at the time of the changes of instructions appearing in the flight plan LTFP. By virtue of this information, the control authority estimates more precisely the actual future position of the aircraft and the changes of instruction, thereby enabling it to increase the safety level in particular for the spacing and separation of traffic.

Abstract: The present invention relates to a method for updating meteorological information for an aircraft. The FMS computer automatically makes the request for the meteorological data so as to anticipate the updating of the latter as soon as an update is available. This automation allows the crew to have the data ready for display and use without waiting, to reduce and smooth the workload of the crew by anticipating the request and the processing of these data, and to limit the potential confusion associated with the receipt, hitherto verbal, of the ATIS information.

Abstract: The present invention relates to a method and a system used by an aircraft to follow a descent trajectory matched with a time schedule. The method is characterized in that the speed of the aircraft is servo-controlled to the speed required to comply with the time schedule by adjusting the pitch angle when the aircraft is not below the planned altitude on the trajectory beyond a threshold and by adjusting the engine thrust when the aircraft is below the planned altitude on the trajectory beyond the threshold.

Abstract: The invention relates to a method of automatically managing the flight of an aircraft in turbulent air comprising notably the determination of the current speed (Vc), of an optimal turbulence speed (Vt), of a current thrust value (P). The data relating to a turbulence is acquired. An optimal turbulence speed is determined. Measuring a deviation (?) between the current speed (Vc) and the turbulence speed (Vt). Comparing the deviation (?) and a maximum deviation value (?max). Iterating k times of the previous three steps, to determine whether the deviation (?) is greater than the maximum deviation (?max) for the kth consecutive time, and the readjustment of the current thrust (P) so as to reduce the deviation (?) to a value less than that of the maximum deviation (?max) and to make the current speed (Vc) converge to the turbulence speed (Vt).

Abstract: The method in accordance with the invention is a method of providing a 3D emergency descent trajectory for aircraft comprising the steps of searching for at least one possible better trajectory allowing a secure continuation in relation to the relief and/or the surrounding conditions towards a homing point as soon as a situation requiring an unscheduled modification of the current trajectory occurs, wherein this trajectory is updated as a function of the alterations in the surrounding conditions, as a function of the information provided by the onboard sensors and/or outside information received.

Abstract: The subject of the present invention is a method for improving route and 4D prediction calculations by FMS in the framework of ATC tactical flight instructions, which method enables the FMS of an aircraft to carry out its usual predictions as precisely as possible when it has left or anticipates leaving its initial flight plan following an instruction from the air traffic controller, and has no instructions telling it where and when to return to the initial flight plan, and the invention is characterized in that it consists in transmitting to the aircraft, from an air traffic control centre, information enabling the FMS system to be aware of traffic crossing points (X1) and control sector changes, and to use this information to predict the coordinates of a point (X2) at which it is supposed to rejoin its initial flight plan at the earliest opportunity after the crossing point that required an alteration of trajectory and at the latest opportunity on the last point of the current sector.

Abstract: The present invention relates to a method and a system for monitoring the following of a reference trajectory by an aircraft.

Abstract: The invention relates to a method for automatic detection of turbulence by a second aircraft, by information exchange between the second aircraft and at least a first aircraft. The first aircraft has means for transmitting information and the second aircraft has means for receiving the information transmitted by the first aircraft. The method includes the identification of information about turbulence liable to be encountered by the second aircraft, by analyzing the information received from the first aircraft. An alarm is activated on the basis of the turbulence information.

Abstract: Flight management systems can behave erratically when the distance measurements on which they are based are subject to value jumps because they liken these value jumps to movements of the aircraft performed at speeds exceeding the performance levels of the aircraft for which they were designed. To avoid this, the proposed flight management system uses a filter to spread the distance value jumps in time, over periods of the order of those needed for the aircraft to come through the distance differences that they represent. This filter replaces a value jump with a ramp making up the difference and corresponding to a movement that remains within the performance scope of the aircraft.

Abstract: The present invention relates to a guidance method for temporarily deviating a vehicle initially following a predefined path. The method is characterized in that the modalities according to which the vehicle leaves the predefined path, accompanied by conditions based on which it rejoins it, are sent to the guided vehicle in the form of an alphanumeric message via a digital data link.

Abstract: The present invention relates to a method for changing the path followed by an aircraft, the aircraft initially following a predefined path on the basis of a sequence of waypoints, the method allowing a subsequent return of the aircraft to the predefined path in the same direction or in the reverse direction. The method allows a possible return of the aircraft to the predefined path in the same direction such that the waypoints of the predefined path are projected onto a new path according to a projection function ensuring that the order of the sequence of the projected image points complies with the order of the sequence of the original waypoints. The projection of a waypoint already reached by the aircraft also is considered as having been reached. The projections of the waypoints on the new path are considered reached by the aircraft progressively as the latter progresses along the new path.

Abstract: The invention relates to a method of changing the approach procedure of an aircraft comprising steps of selecting a new landing runway of the destination airport and of selecting a landing aid system or non-precision approach procedure associated with this runway. The selection steps comprise an automatic selection of a pair associating the new landing runway with the landing aid system or with the non-precision approach procedure, the pair originating from a database containing the pairs related to the destination airport.

Abstract: The invention relates to a method for assisting low-altitude navigation of an aircraft equipped with a system suited to determining a flight-plan ground trajectory based on intermediate points P at an altitude alt(P), and the aircraft's performance.

Abstract: The invention relates to a flight management system for aircraft which makes it possible to carry out tests of the results of the calculations of the main functions for formulating the flight plans and trajectories of the aircraft making it possible to anticipate errors in this formulation, to present them to the crew as a function of criticality criteria, to store them so as to be communicated and processed by the maintenance teams.