Method and device for measuring the angle of attack and the sideslip of an aircraft

1. Method for measuring the angle of attack of the longitudinal axis of an aircraft with respect to the relative wind, in which method a probe is used which is provided, at the front end thereof, with a central directional sensor which is arranged at the intersection of the horizontal and vertical midplanes of said probe, and with at least two eccentric midplane directional sensors which are in parallel with said central directional sensor and are arranged at an equal distance therefrom on either side of said horizontal midplane of said probe, the method comprising:

pivotally connecting said probe to said aircraft about a first pivot axis which is in parallel with said horizontal midplane of said probe and is orthogonal to said longitudinal axis of the aircraft;

rotating said probe about said first pivot axis in order to make said probe assume the particular inclined position in which the measurements provided by said eccentric midplane directional sensors are equal; and

measuring the particular angle of inclination which is produced, in this particular inclined position, between said horizontal midplane of the probe and the longitudinal axis (L-L) of the aircraft,

wherein said probe is provided, at the front end thereof and in addition to said central directional sensor and said eccentric midplane directional sensors, with at least two lateral directional sensors which are in parallel with said central directional sensor and are arranged at an equal distance therefrom on either side of said vertical midplane of said probe, and wherein, in order to measure the sideslip of the aircraft, the method comprises:

pivotally connecting said probe to said aircraft about a second pivot axis which is in parallel with said longitudinal axis of the aircraft;

rotating said probe and said first pivot axis about said second pivot axis in order make said probe assume the particular combined inclined position in which not only are the measurements provided by said eccentric midplane directional sensors equal, but so too are the measurements provided by said lateral directional sensors; and

measuring the particular value of the angle of rotation of said second pivot axis in said particular combined inclined position of the probe.

2. Method according to claim 1 , wherein, during the flight of the aircraft, said particular angle of inclination which is produced between the horizontal midplane of the probe and the longitudinal axis of the aircraft, and said particular value of the angle of rotation of said second pivot axis are continuously determined.

3. Method according to claim 1 , wherein said central directional sensor, said eccentric midplane directional sensors, and said lateral directional sensors are of the same type.

4. Method according to claim 3 , wherein said central directional sensor, said eccentric midplane directional sensors, and said lateral directional sensors are pressure sensors.

5. Method according to claim 3 , wherein said central directional sensor, said eccentric midplane directional sensors, and said lateral directional sensors are temperature sensors.

6. Method according to claim 1 , wherein

in order to rotate said probe about said first pivot axis, an actuator provided with a movable actuation member is used, and said particular angle of inclination is measured by the corresponding position of said movable actuation member of the actuator; and

in order to rotate said probe and said first pivot axis about said second pivot axis, an actuator provided with a movable actuation member is used, and said value of the angle of rotation of said second pivot axis is measured by the corresponding position of said movable actuation member of said actuator.

7. Device for measuring the angle of attack of the longitudinal axis of an aircraft with respect to the relative wind, comprising a probe which is provided, at the front end thereof, with a central directional sensor which is arranged at the intersection of the horizontal and vertical midplanes of said probe, and with at least two eccentric midplane directional sensors which are in parallel with said central directional sensor and are arranged at an equal distance therefrom on either side of said horizontal midplane of said probe, said device comprising:

first means for pivotally connecting said probe to said aircraft about a first pivot axis which is in parallel with said horizontal midplane of said probe and orthogonal to said longitudinal axis of the aircraft;

first means for rotating said probe about said first pivot axis in order to make said probe assume the particular inclined position in which the measurements provided by said eccentric midplane directional sensors are equal; and

first means for measuring the particular angle of inclination which is produced, in this particular inclined position, between said horizontal midplane of the probe and the longitudinal axis of the aircraft,

wherein

said probe is provided, at the front end thereof, in addition to said central directional sensor and said eccentric midplane directional sensors, with at least two lateral directional sensors which are in parallel with said central directional sensor and are arranged at an equal distance therefrom on either side of said vertical midplane of said probe; and

said device further comprises:

second means for pivotally connecting said probe to said aircraft about a second pivot axis which is in parallel with said longitudinal axis of the aircraft;

second means for rotating said probe and said first pivot axis about said second pivot axis in order to make said probe assume the particular combined inclined position in which not only are the measurements provided by said eccentric midplane directional sensors equal, but so too are the measurements provided by said lateral directional sensors; and

second means for measuring the particular value of the angle of rotation of said second pivot axis in said particular combined inclined position of the probe, said angle of rotation representing the sideslip of said aircraft.

8. Aircraft comprising a device for measuring the angle of attack and the sideslip according to claim 7 .