Method and device for verifying a temperature value at a destination altitude of an aircraft

1. A method of verifying a first temperature value corresponding to the temperature at a destination altitude of an aircraft, comprising:

a) measuring a dynamic temperature on the outside of the aircraft, at the actual altitude of said aircraft;

b) determining a static temperature around the aircraft using said dynamic temperature;

c) determining a second temperature value corresponding to an estimated temperature at said destination altitude using said static temperature and a thermodynamic equation;

d) determining the difference between said first and second temperature values; and

e) if said difference is greater than a predetermined value, emitting a warning signal.

2. The method as claimed in claim 1 , wherein, in step b), said static temperature T r1 is determined using the following equation:

T r1 =T r /[1+(0.2 K r M 2 )]

in which:

T r represents the measured dynamic temperature;

K r represents a coefficient; and

M represents the Mach number.

3. The method as claimed in claim 1 , wherein, in step c), said second temperature value T r2 is determined using the following thermodynamic equation:

T r2 =T std2 ( T r1 /T std1 )

in which:

T r1 represents said static temperature at the actual altitude of the aircraft;

T std1 represents the standard temperature at said actual altitude of the aircraft; and

T std2 represents the standard temperature at the destination altitude.

4. The method as claimed in claim 3 , wherein said standard temperature T std1 determined using the following equation:

T std1 =288−( L 0 H 1 )

in which:

L 0 is a coefficient; and

H 1 is the actual altitude of the aircraft.

5. The method as claimed in claim 3 , wherein said standard temperature T std2 as determined using the following equation:

T std2 =288−( L 0 H 2 )

in which:

L 0 is a coefficient; and

H 2 is said destination altitude.

6. The method as claimed in claim 1 , wherein said predetermined value used in step e) is substantially equal to 10° C.

7. A device for verifying a first temperature value corresponding to the temperature at a destination altitude of an aircraft, which comprises:

a measuring section that measures a dynamic temperature on the outside of the aircraft;

a first determining section that determines a static temperature around the aircraft using said dynamic temperature;

a second determining section that determines a second temperature value, corresponding to an estimated temperature at said destination altitude, using said static temperature and a thermodynamic equation;

a difference determining section that determines the difference between said first and second temperature values; and

an emitting section that emits a warning signal when said difference is greater than a predetermined value.

8. A flight management system of an aircraft, comprising at least:

the device specified in claim 7 ;

an input section that allows an operator to input at least one temperature value; and

a central processing unit that corrects at least one altitude value only if the device has verified that the at least one temperature value entered by the operator is precise, wherein:

said device is automatically triggered when a temperature value is input by an operator, so as to verify this temperature value.

9. An aircraft, which includes the system specified in claim 8 .

10. An aircraft, which includes the device specified in claim 7 .

11. An aircraft, which includes a device that implements the method specified in claim 1 .