Method for determining the vertical point for switching from a manual piloting mode to a guided mode

Patent metadata

Field	Value
Publication number	US-9360866-B2
Application number	US-201514747940-A
Country	US
Kind code	B2
Filing date	Jun 23, 2015
Priority date	Jun 27, 2014
Publication date	Jun 7, 2016
Grant date	Jun 7, 2016

Abstract

A method for determining a switch-over vertical point from which an aircraft, having a current position, and flying a current vertical trajectory according to a manual piloting mode having an altitude setpoint, denoted target altitude, loaded by the pilot, switches to a piloting mode guided by a flight management system, in order to rejoin a predefined flight plan having a set of initial altitude constraints, comprising: calculating a first predicted vertical trajectory, determining a first point of intersection between the first predicted trajectory and the target altitude, determining a second predicted trajectory, determining the switch-over vertical point belonging to the first predicted vertical trajectory, based on any incompatible constraints, and as the intersection between the first predicted vertical trajectory and a predicted vertical trajectory calculated by integration of the dynamic flight equations by applying calculation hypotheses for a piloting mode guided by a flight management system.

First claim

The invention claimed is:

1. A method for determining with a flight management system (FMS) that includes a computer a switch-over vertical point from which an aircraft, having a current position, and flying a current vertical trajectory according to a manual piloting mode having an altitude setpoint, denoted target altitude, loaded by a pilot, switches over to a piloting mode guided by the FMS, in order to rejoin a predefined flight plan having a set of initial altitude constraints, the method comprising the steps:
calculating a first predicted vertical trajectory by integration of dynamic flight equations starting from the current position of the aircraft, by extrapolating the current trajectory and by applying calculation hypotheses corresponding to the manual piloting mode for the aircraft,
determining a first point of intersection between the first predicted trajectory and the target altitude, having a first abscissa, the altitude constraints with an abscissa less than the said first abscissa being called anterior constraints, the altitude constraints with an abscissa greater than the said first abscissa being called posterior constraints,
determining a second predicted trajectory by forward integration of the dynamic flight equations starting from the said first intersection point and by applying calculation hypotheses for a piloting mode guided by the FMS,
determining a sub-set of altitude constraints to be complied with indexed by an index i, the index 1 corresponding to the constraint closest to the current position of the aircraft, chosen from amongst the set of initial altitude constraints, each altitude constraint to be complied with having an abscissa,
determining the anterior constraints incompatible with the first predicted trajectory and the posterior constraints incompatible with the second predicted trajectory,
determining the said switch-over vertical point belonging to the first predicted vertical trajectory, using any incompatible constraints, and as the intersection between the said first predicted vertical trajectory and a predicted vertical trajectory calculated by integration of the dynamic flight equations by applying calculation hypotheses for a piloting mode guided by the FMS, and
proposing to the pilot of the aircraft to switch from the manual piloting mode to the piloting mode guided by the FMS when the aircraft reaches said switch-over vertical point.

2. The method according to claim 1 in which the step for determining the switch-over vertical point comprises the sub-steps:
when no constraint is incompatible, the switch-over vertical point is equal to the first point of intersection,
when at least one altitude constraint is incompatible, determining the said switch-over vertical point as the intersection between the first predicted trajectory and a predicted vertical trajectory calculated by backward integration of the dynamic flight equations starting from an associated incompatible constraint, by applying calculation hypotheses for a piloting mode guided by the FMS.

3. The method according to claim 2 in which the step for determining the switch-over point comprises the sub-steps:
for each incompatible constraint:
determining a third associated predicted trajectory by backward integration of the dynamic flight equations starting from the associated incompatible constraint and by applying calculation hypotheses for a piloting mode guided by the FMS,
determining a second associated point of intersection corresponding to the intersection between the first predicted vertical trajectory and the third associated predicted trajectory,

determining the switch-over vertical point, equal to the second associated point of intersection closest to the current position of the aircraft.

4. The method according to claim 1 in which the manual piloting mode is chosen from the group: constant vertical speed managed; constant angle managed; constant altitude managed; and thrust managed.

5. The method according to claim 1 further comprising a step for graphical display of the switch-over vertical point.

6. The method according to claim 1 in which the aircraft is in a climbing phase and in which the calculation hypotheses for the piloting mode guided by the FMS incorporate an operational criterion of the Thrust Climb managed type or of the altitude hold type.

7. The method according to claim 1 in which the aircraft is in a descent phase and must rejoin a predetermined altitude profile and in which the calculation hypotheses for the piloting mode guided by the FMS incorporate an operational criterion that is a function of the position of the aircraft with respect to the predetermined altitude profile.

8. The method according to claim 6 in which the aircraft is situated below the predetermined altitude profile, and in which the operational criterion is of the constant vertical speed managed type or of the altitude hold type.

9. The method according to claim 6 in which the aircraft is situated above the predetermined altitude profile and in which the operational criterion is of the thrust managed (THRUST Idle Managed) type, the said criterion being adjustable by a positioning of airbrakes chosen from amongst the group: no airbrakes (no Airbrake); half-out airbrakes (½ Airbrake); and fully deployed airbrakes (full Airbrake).

10. The method according to claim 1 , further comprising calculating a predicted global trajectory based on the concatenation of at least two portions:
a first portion equal to the first predicted trajectory, up to the switch-over vertical point and
a second portion, starting from the switch-over vertical point, equal to:
the second predicted trajectory when no altitude constraint is incompatible,
the third predicted trajectory associated with the switch-over vertical point when at least one altitude constraint is incompatible.

11. The method according to claim 1 , further comprising the steps:
selecting a chosen point belonging to the first predicted trajectory
replacing the switch-over vertical point by the chosen point,
calculating a predicted global trajectory based on the concatenation of at least two portions:
a first portion equal to the first predicted trajectory, up to the chosen point,
a second portion, starting from the chosen point, corresponding to a trajectory calculated by forward integration of the dynamic flight equations according to a piloting mode guided by the FMS.

12. The method according to claim 11 in which the step for selection of the chosen point is operated by the pilot.

13. The method according to claim 1 in which:
the aircraft is in a descent phase and must rejoin a predetermined altitude profile, and further comprising the steps:
determining a third point equal to the intersection between the first predicted trajectory and the said predetermined altitude profile,
when the said third point is reached prior to the calculated switch-over vertical point:
calculating a predicted global trajectory based on the concatenation of at least two portions:
a first portion equal to the first predicted trajectory, up to the third point,
a second portion, starting from the third point, corresponding to a trajectory calculated by integration of the dynamic flight equations according to a piloting mode guided by the FMS following the predetermined altitude profile.

14. The method according to claim 10 , further comprising a step consisting in calculating predictions of state parameters of the aircraft from a predicted global trajectory.

15. The method according to claim 14 in which the state parameters of the aircraft comprise a pre

Assignees

• Thales Sa

Inventors

• Gutierrez-Castaneda Manuel
• Caudron De Coquereaumont Bertrand
• Jeanjean Xavier

Classifications

• B64C13/18

  using automatic pilot · CPC title

• B64C13/22

  readily revertible to personal control · CPC title

• G08G5/30

  Flight plan management · CPC title

• G08G5/55

  for a single aircraft · CPC title

• G08G5/50

  Navigation or guidance aids · CPC title