Method and device for determining a maximum stabilization height in the final flight phase of an airplane
View Patent ↗A method of determining and utilizing a maximum stabilization height of a moving airplane includes: determining a nominal total height at any point of the nominal path of the airplane, determining a total height of the airplane, determining a nominal maximum total height that the airplane is able to reach from its current position corresponding to a nominal total height and according to an optimum total height variation law, determining the maximum stabilization height corresponding to the nominal maximum total height that the airplane is able to reach, and determining whether to continue or to interrupt a landing procedure during the final flight phase of the airplane based on the determined maximum stabilization height.
1. Method of determining and utilizing a maximum stabilization height h stab of an airplane moving from a current position, at a height h av relative to a reference point and with a speed V av in a final flight phase of said airplane, said final flight phase comprising a nominal approach path roughly in a vertical plane passing through an axis X of a runway and determined by:
nominal height values according to the position along the axis X called height law h nom (X) relative to the reference point;
nominal approach speed values according to the position along the axis X called speed law V nom (X);
wherein the method comprises configuring a computer to:
determine a nominal total height H Tnom at any point of the nominal path by the relation
H
Tnom
(
X
)
=
h
nom
(
X
)
+
(
V
nom
2
(
X
)
)
2
g
in which g represents the earth's gravity field;
determine a total height of the airplane H Tav by the relation
H
Tav
=
h
av
+
V
av
2
2
g
determine a nominal maximum total height that the airplane is able to reach from its current position corresponding to a nominal total height and according to an optimum total height variation law
ⅆ
H
Tav
ⅆ
X
;
and
determine the maximum stabilization height h stab corresponding to the nominal maximum total height that the airplane is able to reach; the method further comprising determining whether to continue or to interrupt a landing procedure during the final flight phase of the airplane based on the determined maximum stabilization height.
2. Method according to claim 1 in which, when the total height of the airplane H Tav is greater than the nominal total height H Tnom (X) for the current value X of the airplane, the optimum total height variation law
ⅆ
H
Tav
ⅆ
X
corresponds to the total height variation law of the airplane when the engines are set to obtain a thrust P roughly equal to the minimum thrust at the flight point concerned.
3. Method according to claim 1 , in which the nominal approach speed V nom (X) is considered constant in the final flight phase.
4. Method according to claim 3 , in which the optimum total height variation law
ⅆ
H
Tav
ⅆ
X
is considered constant in the final flight phase.
5. Method according to claim 4 , in which the stabilization height h stab is determined by a relation:
h
stab
=
h
thd
+
(
h
av
+
V
av
2
2
g
-
h
thd
-
V
nom
2
2
g
-
(
ⅆ
H
Tav
ⅆ
X
)
X
av
)
(
(
tan
γ
gl
)
(
tan
γ
gl
-
(
ⅆ
H
Tav
ⅆ
X
)
)
)
with:
γ gi =the angle of the nominal approach gradient,
h thd =the nominal height of passage of the airplane at the threshold level,
X av =the position of the airplane along the runway axis.
6. Method according to claim 1 , in which the optimum total height variation law
ⅆ
H
Tav
ⅆ
X
is roughly equal to
(
P
-
D
)
m
g
,
in which D represents an aerodynamic drag corresponding to the aerodynamic drag of the airplane during the flight phase concerned and in which m represents a mass corresponding to the mass of the airplane during the flight phase concerned.
7. Method according to claim 6 , in which the thrust P of the engines is disregarded relative to the aerodynamic drag D of the airplane.
8. Method according to claim 1 , comprising a subsequent step in which the maximum stabilization height h stab is compared to a reference minimum height h ref .
9. Method according to claim 8 , in which an alarm is triggered when the maximum stabilization height h stab is less than the reference minimum height h ref .
10. Piloting aid device, comprising:
means of acquiring parameters characteristic of an airplane, of the flight and of a landing environment including nominal height values according to the position along the axis X called height law h nom (X) relative to the reference point, and nominal approach speed values according to the position along the axis X called speed law V nom (X),
calculation means, which determine, from values including the parameters received from the acquisition means, a maximum stabilization height h stab , by:
determining a nominal total height H Tnom at any point of the nominal path by the relation
H
Tnom
(
X
)
=
h
nom
(
X
)
+
(
V
nom
2
(
X
)
)
2
g
in which g represents the earth's gravity field;
determining a total height of the airplane H Tav by the relation
H
Tav
=
h
av
+
V
av
2
2
g
determining a nominal maximum total height that the airplane is able to reach from its current position corresponding to a nominal total height and according to an optimum total height variation law
ⅆ
H
Tav
ⅆ
X
;
and
determining the maximum stabilization height h stab corresponding to the nominal maximum total height that the airplane is able to reach;
means of presenting information characterizing the maximum stabilization height h stab ; and
means for determining whether to continue or to interrupt a landing procedure during the final flight phase of the airplane based on the determined maximum stabilization height.
11. Device according to claim 10 , in which the calculation means comprise at least one computer handling functions other than determining the maximum stabilization height h stab .
12. Device according to claim 10 , in which the information presentation means comprise means of displaying information representative of the stabilization height h stab calculated by the calculation means.
13. Device according to claim 12 , in which the display means comprise at least one screen in a cockpit of the airplane able to present information representative of the stabilization height h stab in graphic form.
14. Device according to claim 12 , in which the display means present information characteristic of a reference minimum height h ref .
15. Device according to claim 10 , in which the information presentation means comprise alarm means able to present an alarm signal when the stabilization height h stab is less than the reference minimum height h ref .
16. Device according to claim 15 , in which the alarm means generate a sound signal in the cockpit of the airplane.
17. Device according to claim 15 , in which the alarm means generate a visual signal in the cockpit of the airplane.
18. A piloting aid device comprising:
means of acquiring parameters characteristic of an airplane, of the flight and of a landing environment,
calculation means, which determine, from values including the parameters received from the acquisition means, a maximum stabilization height h stab ,
means of presenting information characterizing the maximum stabilization height h stab ,
and in which the value of the stabilization height h stab is established according to the method of claim 1 .
19. Airplane including a device, comprising:
means of acquiring parameters characteristic of an airplane, of the flight and of a landing environment including nominal height values according to the position along the axis X called height law h nom (X) relative to the reference point, and nominal approach speed values according to the position along the axis X called speed law V nom (X),
calculation means, which determine, from values including the parameters received from the acquisition means, a maximum stabilization height h stab , by:
determining a nominal total height H Tnom at any point of the nominal path by the relation
H
Tnom
(
X
)
=
h
nom
(
X
)
+
(
V
nom
2
(
X
)
)
2
g
in which g represents the earth's gravity field;
determining a total height of the airplane H Tav by the relation
H
Tav
=
h
av
+
V
av
2
2
g
determining a nominal maximum total height that the airplane is able to reach from its current position corresponding to a nominal total height and according to an optimum total height variation law
ⅆ
H
Tav
ⅆ
X
;
and
determining the maximum stabilization height h stab corresponding to the nominal maximum total height that the airplane is able to reach;
means of presenting information characterizing the maximum stabilization height h stab ; and
means for determining whether to continue or to interrupt a landing procedure during the final flight phase of the airplane based on the determined maximum stabilization height.
20. Airplane in which a maximum stabilization height h stab is established according to a method of determining and utilizing a maximum stabilization height h stab of the airplane when moving from a current position, at a height h av relative to a reference point and with a speed V av in a final flight phase of said airplane, said final flight phase comprising a nominal approach path roughly in a vertical plane passing through an axis X of a runway and determined by:
nominal height values according to the position along the axis X called height law h nom (X) relative to the reference point;
nominal approach speed values according to the position along the axis X called speed law V nom (X);
wherein the method comprises configuring a computer to:
determine a nominal total height H Tnom at any point of the nominal path by the relation
H
Tnom
(
X
)
=
h
nom
(
X
)
+
(
V
nom
2
(
X
)
)
2
g
in which g represents the earth's gravity field;
determine a total height of the airplane H Tav by the relation
H
Tav
=
h
av
+
V
av
2
2
g
determine a nominal maximum total height that the airplane is able to reach from its current position corresponding to a nominal total height and according to an optimum total height variation law
ⅆ
H
Tav
ⅆ
X
;
and
determine the maximum stabilization height h stab corresponding to the nominal maximum total height that the airplane is able to reach;
the method further comprising determining whether to continue or to interrupt a landing procedure during the final flight phase of the airplane based on the determined maximum stabilization height.