Patent Application
20240169849
This application claims the benefit of the French patent application No. 2211937 filed on Nov. 17, 2022, the entire disclosures of which are incorporated herein by way of reference.
The present invention relates to a method and avionics computer for adapting an anchor point of a terminal segment of a virtual path for a non-precision FLS approach mode of an aircraft, with a view to landing the aircraft on a runway of an aerodrome, and to a procedure and set of systems for implementing such a non-precision approach mode, comprising such a method and such a device, respectively.
In the context of the present invention, a “non-precision approach” is understood to mean an approach that is not a precision instrument approach such as, for example, an ILS approach (ILS standing for Instrument Landing System), which uses, in particular, runway-edge ground stations and a dedicated radio receiver installed on board the aircraft.
An approach is a non-precision approach, such as considered in the present invention, when the above equipment is not available or in operation, at least in part, so that a conventional precision approach cannot be implemented. The present invention applies to a non-precision FLS approach (FLS standing for FMS Landing System and FMS standing for Flight Management System).
To implement this approach, using a non-precision FLS approach mode (or FLS mode), it is necessary to determine a virtual path, corresponding to the theoretical path that the aircraft must follow during this approach. Guiding the aircraft then consists in attempting to cancel out any discrepancies between the actual position of the aircraft and the position it would have if it were on this virtual path. Conventionally, the virtual path comprises a terminal segment, namely the last segment before reaching the runway. This terminal segment is defined with respect to a downstream end point called an anchor point.
Implementing FLS mode provides important assistance to the pilot of the aircraft, in particular by carrying out various guidance, monitoring and, if necessary, warning operations.
However, in order for this FLS mode to be able to be implemented as far as a touchdown zone on the runway, the anchor point must be positioned appropriately, in particular with respect to the runway threshold. Indeed, in the absence of such appropriate positioning, FLS mode cannot be implemented as far as the touchdown zone and implementation thereof is stopped at a certain distance from the runway.
Now, depending on its determination, the anchor point is not always positioned as needed to implement an FLS mode.
This usual system for implementing a non-precision FLS approach mode may therefore be further improved, in particular in terms of availability.
One objective of the present invention is to improve the implementation of a non-precision FLS approach mode of an aircraft. To this end, it relates to a method for adapting an anchor point of a terminal segment of a virtual path for a non-precision FLS approach mode (or FLS mode) of an aircraft, with a view to landing the aircraft on a runway of an aerodrome, the method being implemented in an avionics computer, in particular, a flight management system (FMS) (or computer), comprising at least a processing unit and a navigation database.
According to the invention, the method comprises at least the following steps, implemented by the processing unit:
Thus, by virtue of the invention, when the abovementioned conditions are met, an appropriate anchor point that is located on the threshold of the runway is defined. By virtue of this new positioning of the anchor point, it is possible to implement an FLS mode until landing (that is to say, as far as a touchdown zone of the runway) and therefore benefit from the advantages (guidance, monitoring, warning), specified below, of FLS mode, which could not have been implemented without this adaptation.
It will be noted that this adaptation, that is to say, this displacement of the anchor point, slightly offsets the anchor point laterally by at most around ten meters with respect to the position of the initial anchor point, this being negligible in terms of implementation authorization and safety.
In one preferred embodiment, the predetermined distance is of the order of 0.14 nautical miles (around 260 meters).
The present invention also relates to a procedure for implementing a non-precision FLS approach mode of an aircraft, with a view to landing the aircraft on a runway of an aerodrome, the procedure using a virtual path a terminal segment of which is defined with respect to an anchor point, the procedure being implemented by a set of avionics systems.
According to the invention, the procedure comprises at least a method for adapting an anchor point as described above and uses the anchor point determined by the avionics computer as anchor point of the terminal segment of the virtual path.
Advantageously, the procedure, during the landing of the aircraft, guides the aircraft at least along the terminal segment of the virtual path, as far as a touchdown zone on the runway.
In addition, advantageously, the procedure, during the landing of the aircraft, monitors the aircraft as far as a touchdown zone on the runway, so as to detect, where applicable, at least one (vertical and/or horizontal) deviation of the current position of the aircraft with respect to the terminal segment of the virtual path.
Furthermore, advantageously, the procedure, in the event of detection of a (vertical and/or horizontal) deviation greater than a predetermined value, emits at least one of the following warnings in the cockpit of the aircraft: a visual warning, an acoustic warning.
The present invention furthermore relates to an avionics computer, in particular to a flight management system (or computer), for adapting an anchor point of a terminal segment of a virtual path for a non-precision FLS approach mode of an aircraft, with a view to landing the aircraft on a runway of an aerodrome, the avionics computer comprising at least a processing unit and a navigation database.
According to the invention, the processing unit is configured:
The present invention also relates to a set of avionics systems for implementing a non-precision FLS approach mode of an aircraft, with a view to landing the aircraft on a runway of an aerodrome, the set comprising at least one flight management system configured to use a final virtual path a terminal segment of which is defined with respect to an anchor point.
According to the invention, the set (of systems) comprises at least one avionics computer for adapting an anchor point as described above, and the set (of systems) is configured to use the anchor point defined by the avionics computer as an anchor point of the terminal segment of the virtual path.
In a preferred embodiment, the set additionally comprises at least one of the following systems: a flight warning system, a flight guidance system, a terrain avoidance and warning system, and is configured to implement at least one of the following actions during the landing of the aircraft:
Moreover, the present invention also relates to an aircraft, in particular a cargo aircraft, which comprises at least an avionics computer and/or at least a set of systems, such as those described above.
The appended figures will make it easy to understand how the invention may be implemented. In these figures, identical references denote similar elements.
The avionics computer 1, shown schematically in
In one preferred embodiment, this avionics computer 1 corresponds to a flight management system (FMS) (or computer) of an aircraft AC, for example of a cargo aircraft.
In one preferred application, this avionics computer 1 forms part of a set 2 of systems that is intended to implement a non-precision FLS approach mode (referred to as an “FLS mode” below) of the aircraft AC.
In the examples of
The set 2, as is conventional and as explained in more detail below, allows a (final) virtual path TV to be determined and the aircraft AC to be made to follow it to implement an FLS mode, with a view to landing the aircraft AC on the runway 3. As also explained below, the set 2 determines the (possible) lateral and vertical deviations of the current position PC of the aircraft AC with respect to this virtual path TV (or virtual approach axis), and the aircraft AC is then piloted so as to cancel out these deviations.
The set 2 (which is located on board the aircraft AC, as shown highly schematically in
This virtual path TV comprises a terminal segment 5. This terminal segment 5 corresponds to a straight-line segment that, in the direction (illustrated by an arrow F) of flight of the aircraft AC during the approach, starts at a fix FAF (FAF standing for final approach fix), that is to say, an upstream point or fix representing the place where final approach begins, and it has a particular slope, generally of the order of 3°. In the following description, the terms “upstream” and “downstream” are defined with respect to the direction of flight of the aircraft AC, indicated by the arrow F in
The terminal segment 5 ends at a downstream point representing an anchor point AP.
The purpose of the avionics computer 1 is to adapt, in certain conditions, the anchor point AP of the terminal segment 5 and to provide it to the set 2 so that it uses it to implement FLS mode.
To this end, the avionics computer 1 comprises at least, as shown in
More specifically, the processing unit 8 is configured:
To implement FLS mode, the set 2 comprises, in addition to the avionics computer 1, a plurality of conventional systems grouped together into a subset 9 in
To implement FLS mode, the set 2 may also additionally use other conventional systems or means grouped together into a subset 14 in
In one preferred embodiment, and as described in more detail below, the set 2 (of systems) is configured, during the landing of the aircraft AC, to implement the following actions:
The avionics computer 1, as described above, is intended to implement a method P (shown in
In terms of its implementation, the method P forms part of a procedure M (
As shown in
The method P takes into account the position (that is to say, the latitude, the longitude, and the altitude) of the initial anchor point 7.
The initial anchor point 7 (which represents the anchor point considered by the set 2 before the adaptation implemented by the avionics computer 1) may correspond to the MAP point (explained below) or else to a point determined by a conventional computing means (in particular, the avionics computer 1) of the set 2. This initial anchor point 7 then represents a “pseudo-FEP”, that is to say, a point having the characteristics of a final end point (FEP) but that has not been coded as an FEP point, but determined by a computing means of the set 2.
The method P also takes into account the position (that is to say, the latitude, the longitude, and the altitude) of the landing threshold point LTP (hereinafter LTP point) of the runway 3. The LTP (landing threshold point), which is recorded in the navigation database 6, is a point located laterally at the intersection between the threshold 12 (that is to say, the upstream edge of the runway 3, which is orthogonal to the axis 3A of the runway 3 and has a length equal to the width L of the runway 3) of the runway 3 and the axis 3A of the runway 3, and vertically at a runway threshold height TCH (threshold crossing height). This height TCH is either coded in the navigation database 6 or recorded in a memory of the avionics computer 1, and is generally equal to 50 feet (around 15 meters) in this case.
The comparison step E1, implemented by the processing unit 8, comprises:
In one preferred embodiment, the predetermined distance dAP is of the order of 0.14 nautical miles (around 260 meters).
Furthermore, the checking step E2, also implemented by the processing unit 8, comprises checking whether the direction of the initial terminal segment 5A of the virtual path TV crosses the threshold 12 of the runway 3.
In the context of the present invention, it is considered that the direction of the initial terminal segment 5A crosses the threshold 12 when the direction of the initial terminal segment 5A (that is to say, the initial terminal segment 5A or the upstream extension of the initial terminal segment 5A) crosses a vertical plane of width equal to the width L of the runway 3 and that passes through the threshold 12 of the runway 3.
The abovementioned condition (the direction of the terminal segment 5A crosses the threshold 12) is therefore met if, laterally, the initial anchor point 7 is offset at most by a distance L/2 from the LTP point.
The computing step E3, implemented by the processing unit 8, comprises adapting the anchor point AP if the abovementioned two conditions, satisfied in the comparison step E1 and in the monitoring step E2, respectively, are met simultaneously:
If these two conditions are met, the computing step E3 defines the LTP point as an anchor point AP (instead of the initial anchor point 7).
In the first example shown in
In this example, the abovementioned conditions are indeed met. On the one hand, the projection of the extension of the initial terminal segment 5A does cross the threshold 12 of the runway 3. On the other hand, the distance D1 between the initial anchor point 7 and the point is much less than the distance dAP.
In this first example, the anchor point AP determined by the avionics computer 1 therefore corresponds to the LTP point and the terminal segment 5 (between the fix FAF and the point AP) is aligned with the initial terminal segment 5A (between the fix FAF and the point 7).
Depending on the position, the initial anchor point may sometimes correspond to a missed approach point (MAP), or MAP point, relative to the runway 3. The MAP point, which is published, corresponds to the limit point at which the pilot must, at the latest, initiate a go-around when the corresponding approach is missed (this, in particular, being the case when the pilot is unable to see the runway 3 before reaching this MAP point).
Moreover, in the second example shown in
In this example, the abovementioned conditions are also met. On the one hand, the projection of the extension of the initial terminal segment 5 does cross the threshold 12 of the runway 3. On the other hand, the distance D2 between the initial anchor point 7 and the LTP point is much less than the distance dAP.
In this second example, the anchor point AP determined by the avionics computer 1 therefore also corresponds to the LTP point.
In this case, the terminal segment 5 (of the virtual path TV) followed by the aircraft AC (which ends at this anchor point AP) is parallel to the initial terminal segment 5A connecting the fix FAF to the initial anchor point 7, while being offset (laterally) by a lateral offset DEV.
In this example, the terminal segment 5 of the virtual path TV that is followed by the aircraft AC is thus offset slightly, laterally (that is to say, in the horizontal plane), with respect to the initial terminal segment 5A. This lateral offset DEV is less than or equal to half the width L of the runway 3, otherwise the initial terminal segment 5 would not cross the threshold 12 of the runway 3. This lateral offset DEV is therefore small, generally less than 0.01 NM (around 18.5 meters), and is negligible (in particular, having no negative impact on safety and not preventing implementation thereof).
The terminal segment 5 has the same slope as the initial terminal segment 5A, and it ends at the anchor point AP.
Moreover, as indicated above, the procedure M, which implements FLS mode using the set 2 (of systems), comprises the method P for adapting the anchor point AP as described above, and uses the anchor point AP determined by the method P as an anchor point of the terminal segment 5 of the virtual path TV.
To this end, when FLS mode is active, that is to say, during the approach of the aircraft AC and the landing of the aircraft AC, as far as the touchdown zone 18 of the runway 3, the procedure M implements (using the set 2) various steps or operations specified below.
The procedure M comprises a guidance step (or operation) EA, implemented continuously, comprising guiding the aircraft AC along the terminal segment 5 of the virtual path TV as far as the touchdown zone 18 on the runway 3.
Guiding the aircraft AC comprises canceling out any discrepancies (which are detected continuously) between the current position PC of the aircraft AC, determined as specified below, and the position it would have if it were on the virtual path TV. In the example of
The display system 17 displays these discrepancies (or deviations) on screens that are installed in the cockpit of the aircraft AC.
The display system 17 comprises, for example, the primary flight parameter screen (PDF, primary flight display) 19, shown in
The screen 19 comprises, as is conventional, a flight indicator 22, a heading indicator 23, an altitude indicator 24 and a speed indicator 25.
When implementing FLS mode, the display system 17 displays, in particular, the following information on the screen 19:
In one particular embodiment, the terrain avoidance and warning system 13 activates, where applicable, the “F-G/S” and “F-LOC” modes.
The flight indicator 22 indicates that the aircraft AC is located below the virtual path, as in the example of
In addition, the display system 17 also comprises the navigation screen 20, which comprises, as is conventional and as shown in
In the example shown, relating to the situation of
In one particular embodiment, the current position PC of the aircraft AC, which is used for guidance, is determined by the processing unit 8 of the avionics computer 1 (flight management system). To this end, the processing unit 8, in a conventional manner, consolidates:
Furthermore, the procedure M also comprises a monitoring step EB, implemented continuously, comprising, during the landing of the aircraft AC, monitoring the aircraft AC as far as the touchdown zone 18 on the runway 3.
This monitoring step EB is capable of detecting, where applicable, a deviation, such as the vertical deviation PDEz of
Moreover, the procedure M comprises a warning step EC comprising, in the event of detection (in the monitoring step EB) of a vertical deviation and/or of a horizontal deviation that is greater than a predetermined value, emitting one or more warnings in the cockpit of the aircraft.
To warn the pilot of such an excessive deviation situation, the acoustic warning unit 21 emits an acoustic signal in the cockpit of the aircraft AC.
In addition, the display unit 17 outputs, on the screen 19, at least one characteristic symbol 28, preferably in flashing form, so as to warn the pilot of the aircraft of this excessive deviation.
To this end, depending on the envisaged architecture of the set 2, the flight warning system 10 or the flight guidance system 11 provides instructions to the display system 17 so that it produces such a display.
The avionics computer 1 and the method P (and the set 2 and the procedure M that use the anchor point determined by the avionics computer 1 and the method P), as described above, have many advantages. In particular, they have advantages:
The systems and devices described herein may include a controller, control unit, control device, controlling means, system control, processor, computing unit or a computing device comprising a processing unit and a memory which has stored therein computer-executable instructions for implementing the processes described herein. The processing unit may comprise any suitable devices configured to cause a series of steps to be performed so as to implement the method such that instructions, when executed by the computing device or other programmable apparatus, may cause the functions/acts/steps specified in the methods described herein to be executed. The processing unit may comprise, for example, any type of general-purpose microprocessor or microcontroller, a digital signal processing (DSP) processor, a central processing unit (CPU), an integrated circuit, a field programmable gate array (FPGA), a reconfigurable processor, other suitably programmed or programmable logic circuits, or any combination thereof.
The memory may be any suitable known or other machine-readable storage medium. The memory may comprise non-transitory computer readable storage medium such as, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. The memory may include a suitable combination of any type of computer memory that is located either internally or externally to the device such as, for example, random-access memory (RAM), read-only memory (ROM), compact disc read-only memory (CDROM), electro-optical memory, magneto-optical memory, erasable programmable read-only memory (EPROM), and electrically-erasable programmable read-only memory (EEPROM), Ferroelectric RAM (FRAM) or the like. The memory may comprise any storage means (e.g., devices) suitable for retrievably storing the computer-executable instructions executable by processing unit.
The methods and systems described herein may be implemented in a high-level procedural or object-oriented programming or scripting language, or a combination thereof, to communicate with or assist in the operation of the controller or computing device. Alternatively, the methods and systems described herein may be implemented in assembly or machine language. The language may be a compiled or interpreted language. Program code for implementing the methods and systems described herein may be stored on the storage media or the device, for example a ROM, a magnetic disk, an optical disc, a flash drive, or any other suitable storage media or device. The program code may be readable by a general or special-purpose programmable computer for configuring and operating the computer when the storage media or device is read by the computer to perform the procedures described herein.
Computer-executable instructions may be in many forms, including program modules, executed by one or more computers or other devices. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform particular tasks or implement particular abstract data types. Typically, the functionality of the program modules may be combined or distributed as desired in various embodiments.
While at least one exemplary embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without departing from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the exemplary embodiment(s). In addition, in this disclosure, the terms “comprise” or “comprising” do not exclude other elements or steps, the terms “a” or “one” do not exclude a plural number, and the term “or” means either or both. Furthermore, characteristics or steps which have been described may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or application from which it claims benefit or priority.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2211937 | Nov 2022 | FR | national |
