Field 5 of the invention
[0001] The present invention relates to the field of air navigation, and more
particularly to the field of navigation along flight plan procedures.
Prior art
[0002] Flight management systems (FMS) nowadays allow operators to select
10 procedures by inserting them into flight plans. These procedures may for example
consist of the approach to a runway with its associated go-around procedure.
[0003] In modern FMSs, procedures are selected manually by the operator (for
example, the aircraft pilot, or a remote drone operator), and then followed by the
FMSs. An operator is thus able, during the flight, to select a new procedure that will
15 be followed by the FMS. However, this manual selection of new procedures may
increase the workload of the operator, and thus be a source of unsafeness for the
aircraft. This is particularly true in the approach phase, which is both the phase when
the need for a change of procedure is most common, for example in the event of a
runway change imposed by air traffic control or in the event of a go-around, and the
20 phase in which the operator is the most stressed.
[0004] Thus, in the approach phase, an operator may have to select a second
procedure following the initial approach and extend guidance from one to the other,
in parallel with communications with the air traffic controller, while at the same time
ensuring that the aircraft remains safe in a complex environment (close to the ground,
25 often dense traffic near airports, possibility of hazardous terrain for airports in
mountainous areas, etc.).
[0005] There is therefore a need for a method that makes it possible to automate,
with a view to the approach phase, the activation of a second procedure that makes it
possible to safeguard the trajectory of the aircraft in order to complete the landing
30 successfully.
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Summary of the invention
[0006] To this end, one subject of the invention is a computer-implemented method
comprising: loading an initial active flight plan for an aircraft comprising a first
approach procedure to a runway up to a missed approach point, and a missed
approach procedure between said missed approach point and a final 5 point; loading a
secondary flight plan comprising a second approach procedure to the runway
between the missed approach point and the runway, said second approach
procedure following the first approach procedure, and a second missed approach
procedure at the end of said second approach procedure, and ending at a second
10 final point; receiving an instruction from an operator of the aircraft to link the initial
active flight plan and the secondary flight plan, said link consisting of an association
between the active flight plan and the secondary flight plan, allowing automatic
selection of one or the other; in the event of a go-around by the operator at the latest
at said missed approach point, activating said missed approach procedure; otherwise,
15 automatically selecting the secondary flight plan as active flight plan.
[0007] Advantageously, the method comprises, in the event of a go-around during a
predetermined period after passing the missed approach point, automatically
selecting the initial flight plan as current flight plan, and activating said missed
approach procedure.
20 [0008] Advantageously, the guidance instruction active at the time of the automatic
selection of the secondary flight plan as active flight plan is maintained during said
predetermined period.
[0009] Advantageously, the roll rate of the aircraft is limited to a predefined roll rate
during said predetermined period.
25 [0010] Advantageously, the method comprises, when the secondary flight plan is
selected as active flight plan, inserting a DF segment to the first waypoint of the
second approach procedure.
[0011] Advantageously, the method comprises, in the event of a go-around after said
predetermined period after passing the missed approach point, activating the second
30 missed approach procedure.
[0012] Advantageously, said second final point and said final point are collocated.
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[0013] Advantageously, the secondary flight plan is established manually by the
aircraft operator during a flight phase.
[0014] Advantageously, the aircraft operator sends, to the flight management system
of the aircraft, a request to automatically obtain a secondary flight plan, and: the flight
management system generates a plurality of candidate secondary 5 flight plans:
starting at the missed approach point; and passing through the runway; and ending
at said second final point; the operator selects the secondary flight plan from among
said candidate secondary flight plans.
[0015] Advantageously, the method comprises the flight management system of the
10 aircraft converting, when one of the initial and secondary flight plans is activated, said
flight plan into a trajectory, and one action at least from among sending instructions
to follow the trajectory to an autopilot and displaying the trajectory to the aircraft
operator.
[0016] Another subject of the invention is a computer program comprising program
15 code instructions recorded on a computer-readable medium, said program code
instructions being configured, when said program runs on a computer, to execute a
method according to the one of the embodiments of the invention.
[0017] Another subject of the invention is a flight management system for an aircraft,
comprising computing means configured to execute a method according to one of the
20 embodiments of the invention.
[0018] Other features, details and advantages of the invention will become apparent
upon reading the description given with reference to the appended drawings, which
are given by way of example and in which, respectively:
- figure 1 shows an FMS system in which the invention may be implemented;
25 - figure 2 shows one example of a method in one set of embodiments of the
invention;
- figure 3 shows one example of an approach to an airport according to one set
of modes of implementation of the invention;
- figure 4 shows one example of a depiction of a flight plan and procedures
30 according to one set of modes of implementation of the invention;
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- figure 5 shows a display of waypoints to the operator in one set of
embodiments of the invention;
- figure 6 shows a modification of the display of waypoints to the operator in one
set of embodiments of the invention.
[0019] Some acronyms commonly used in the technical field 5 of the present
application may be used in the description. These acronyms are listed in the table
below, notably with their English expression and their meaning.
Acronym Expression Meaning
DF Direct to Fix Direct to fix. Type of navigation segment,
comprising a join to the next waypoint with a
gradual change in the heading of the aircraft from
the initial heading.
FAF Final Approach
Fix
Final approach fix. Designates a waypoint in a
navigation database defined for an airport
instrument approach. This is the starting point for
the final segment of the approach.
FPLN Flight Plan Flight plan. Description of the flight followed by
the aircraft, and notably the waypoints describing
the route thereof.
FMD Flight
Management
Display
Display, in a cockpit, of Flight Management data
in the form of pages or windows. System for
displaying data supplied by an FMS system.
FMS Flight
Management
System
Flight Management System. Computerized system
for computing trajectories and flight plans for
aircraft, and for supplying guidance instructions
adapted to the operator or autopilot to follow the
computed trajectory.
IF Intermediate Fix Intermediate approach fix. Designates a waypoint
in a navigation database defined for an airport
instrument approach. This is an intermediate
point of an approach to the airport, separating
the initial segment from the intermediate
segment of the approach.
KCCU Keyboard
Console Control
Unit
Keyboard Cursor Control Unit. Human-Machine
Interface able to be integrated into a cockpit,
comprising a keyboard so that the operator is
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5
10
[0020] F
igure
15 1
shows an FMS system in which the invention may be implemented.
[0021] A flight management system may be implemented by at least one computer on
board an aircraft or on board a ground station. According to various embodiments of
the invention, it may be a flight management system for various types of aircraft, for
20 example an airplane, a helicopter or a drone. The FMS 100 determines notably a
geometry of a flight plan profile followed by the aircraft. The trajectory is computed in
four dimensions: three spatial dimensions and a time/speed profile dimension. The
FMS 100 also transmits, to the operator, via a first operator interface, or to the
autopilot, guidance instructions computed by the FMS 100 to follow the flight profile.
25 The operator may be located in the aircraft, for example if the aircraft is an airplane
or a helicopter, or else on the ground, for example if the aircraft is a drone.
[0022] A flight management system may comprise one or more databases such as
the database PERF DB 150, and the database NAV DB 130. For example, the
database PERF DB 150 may contain aerodynamic parameters of the aircraft, or else
30 features of the engines of the aircraft. It contains notably the performance margins
able to enter information into the FMS.
MAP or
MAPT
Missed Approach
PoinT
Missed Approach Point. Designates a waypoint
defined for an airport in a navigation database. It
corresponds to the point from which, if a visual
reference (for example a runway) is not visible to
the operator, said operator has to perform a
missed approach procedure.
MCDU Multi-purpose
Control Display
Unit
Multifunction Display Unit. Human-Machine
Interface able to be integrated into a cockpit,
allowing the display and entry of numerous
information related to the FMS.
ND Navigation
Display
Navigation Screen. Cockpit display element
showing in particular the lateral flight trajectory.
VD Vertical Display Vertical Display. Display element able to be
integrated into a cockpit, and displaying the
reference profile and the vertical joining profile of
the aircraft.
WPT WayPoinT Waypoint. In air navigation, designates a point on
the route to be reached where a change of
heading has to take place.
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applied systematically in the prior art to guarantee safety margins on the descent and
approach phases. The database NAV DB 130 may for example contain the following
elements: geographical points, beacons, air routes, departure procedures, arrival
procedures, altitude constraints, speed constraints or slope constraints.
[0023] The management of a flight plan according to the prior art 5 may invoke means
allowing the aircraft flight crew to create/modify a flight plan through one or more
human-machine interfaces, for example :
· the MCDU;
· the KCCU;
10 · the FMD;
· the ND;
· the VD.
[0024] This flight plan creation/modification may for example comprise the loading of
15 procedures by the operator, along with the selection of a procedure to be added to
the current flight plan.
[0025] The FMS 100 comprises a flight plan management module 110, usually called
FPLN. The module FPLN 110 notably makes it possible to manage various
geographical elements forming a skeleton of a route to be followed by the aircraft
20 comprising: a departure airport, waypoints, air routes to be followed, an arrival airport.
The module FPLN 110 also makes it possible to manage various procedures forming
part of a flight plan such as: a departure procedure, an arrival procedure. The FPLN
110 capability makes it possible notably to create, modify and delete a primary or
secondary flight plan.
25 [0026] The flight plan and its various information related notably to the corresponding
trajectory computed by the FMS may be displayed for consultation by the flight crew
using display devices, also called human-machine interfaces, which are present in
the cockpit of the aircraft, such as an FMD, an ND, a VD.
[0027] The module FPLN 110 uses data stored in databases PERF DB 150 to
30 construct a flight plan and the associated trajectory.
[0028] The FMS 100 also comprises a module TRAJ 120 for computing a lateral
trajectory for the flight plan defined by the module FPLN 110. The module TRAJ 120
notably constructs a continuous trajectory from points of an initial flight plan while at
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the same time complying with the performance of the aircraft as supplied by the
database PERF DB 150. The initial flight plan may be an active flight plan or a
secondary flight plan. The continuous trajectory may be presented to the operator by
way of one of the human-machine interfaces.
[0029] The FMS 100 also comprises a trajectory prediction module 5 PRED 140. The
module PRED 140 notably constructs an optimized vertical profile from the lateral
trajectory of the aircraft as supplied by the module TRAJ 120. To this end, the
module PRED 140 uses the data from the first database PERF DB 150. The vertical
profile may be presented to the operator by way of a VD, for example.
10 [0030] The FMS 100 also comprises a localization module 170, called LOCNAV in
figure 1. The module LOCNAV 170 notably performs optimized geographical
localization, in real time, of the aircraft on the basis of geolocation means on board
the aircraft.

CLAIMS
1. A computer-implemented method (200) comprising:
- loading an initial active flight plan (210) for an aircraft comprising a first
approach procedure (310) to a runway (350) up to a missed approach 5 point (MAP),
and a missed approach procedure (320) between said missed approach point (MAP)
and a final point (323);
- loading a secondary flight plan (220) comprising a second approach procedure
(330) to the runway (350) between the missed approach point (MAP) and the runway,
10 said second approach procedure following the first approach procedure and a
second missed approach procedure (340) at the end of said second approach
procedure, and ending at a second final point;
- receiving (221) an instruction from an operator of the aircraft to link the initial
active flight plan and the secondary flight plan, said link consisting of an association
15 between the active flight plan and the secondary flight plan, allowing automatic
selection of one or the other;
- in the event (230) of a go-around by the operator at the latest at said missed
approach point, activating (240) said missed approach procedure (320);
- otherwise, automatically selecting the secondary flight plan as active flight plan
20 (250).
2. The method as claimed in claim 1, comprising, in the event of a go-around
during a predetermined period after passing the missed approach point (260),
automatically selecting the initial flight plan as current flight plan (270), and activating
25 (240) said missed approach procedure (320).
3. The method as claimed in claim 2, wherein the guidance instruction active at
the time of the automatic selection of the secondary flight plan as active flight plan is
maintained during said predetermined period.
30
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4. The method as claimed in claim 2, wherein the roll rate of the aircraft is limited
to a predefined roll rate during said predetermined period.
5. The method as claimed in claim 2, comprising, when the secondary flight plan
is selected as active flight plan (250), inserting a DF segment to the 5 first waypoint of
the second approach procedure.
6. The method as claimed in one of claims 2 to 5, comprising, in the event of a
go-around after said predetermined period after passing the missed approach point
10 (MAP), activating the second missed approach procedure (340).
7. The method as claimed in one of claims 1 to 6, wherein the secondary flight
plan is established manually by the aircraft operator during a flight phase.
15 8. The method as claimed in one of claims 1 to 6, wherein the aircraft operator
sends, to the flight management system of the aircraft, a request to automatically
obtain a secondary flight plan, and wherein:
- the flight management system generates a plurality of candidate secondary
flight plans:
20 o starting at the missed approach point (MAP); and
o passing through the runway (350); and
o ending at said second final point;
- the operator selects the secondary flight plan from among said candidate
secondary flight plans.
25
9. The method as claimed in one of claims 1 to 8, comprising the flight
management system of the aircraft converting, when one of the initial and secondary
flight plans is activated, said flight plan into a trajectory, and one action at least from
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among sending instructions to follow the trajectory to an autopilot and displaying the
trajectory to the aircraft operator.
10. A computer program comprising program code instructions recorded on a
computer-readable medium, said program code instructions being 5 configured, when
said program runs on a computer, to execute a method as claimed in one of claims 1
to 9.
11. A flight management system for an aircraft, comprising computing means
10 configured to execute a method as claimed in one of claims 1 to 9.