Aircraft comprising a device for influencing the directional stability of the aircraft, and a method for influencing the directional stability of the aircraft

Patent metadata

Field	Value
Publication number	US-9315255-B2
Application number	US-201013255246-A
Country	US
Kind code	B2
Filing date	Mar 17, 2010
Priority date	Mar 17, 2009
Publication date	Apr 19, 2016
Grant date	Apr 19, 2016

Abstract

An aircraft including a device for influencing the directional stability of the aircraft is provided. The device includes a control-input device; a flight control device; a sensor device for acquiring the rotation rates, including the yaw rates, of the aircraft; and at least one actuator, which is coupled with ailerons, spoilers, an elevator and a rudder. The flight control device includes a control function generating adjusting commands for the actuators for controlling the aircraft according to control commands. The aircraft includes two tail-mounted flaps, each including an actuator connected with the flight control device, situated symmetrically to each other and on opposite sides of the fuselage, and movable between retracted and extended positions. The control function is designed such that the adjusting commands that are generated on the basis of the control commands depending on the acquired rotation rates include adjusting commands to the actuators of the tail-mounted flaps.

First claim

The invention claimed is:

1. An aircraft comprising a device for influencing the directional stability of the aircraft, with the aircraft comprising: wings with ailerons and a rudder, with the device for influencing the directional stability of the aircraft comprising:
a control-input device for inputting control demands for controlling the flight path of the aircraft,
a flight control device that is functionally connected with the control-input device,
a sensor device that is functionally connected with the flight control device, for acquiring the rotation rates, including the yaw rates, of the aircraft,
in each case at least one actuator, which is functionally connected with the flight control device, for adjusting the ailerons and for adjusting the rudder, wherein the flight control device comprises a control function that is designed in such a manner that from the control demands and the rotation rates said flight control device generates adjusting commands for the actuators for controlling the aircraft and transmits them to said actuators, wherein:
the aircraft comprises two tail-mounted flaps, situated behind the connecting region of the wings and on opposite sides of the fuselage, each tail-mounted flap being coupled to an actuator that is functionally connected with the flight control device for moving the tail-mounted flaps between a retracted and an extended position,
the control function is designed in such a manner that for lateral control of the aircraft, on the basis of rotation rates about a z-axis of the aircraft acquired by the sensor device, the control function generates commands for actuating of at least one of the tail-mounted flaps and transmits the commands to said actuator for actuating the tail-mounted flaps such that a moment about the z-axis of the aircraft is effected, and
in response to a deflection of at least one of the tail-mounted flaps, additional drag is generated which in turn generates the moment about the z-axis of the aircraft.

2. The aircraft according to claim 1 , wherein the control function is designed in such a manner that for lateral control of the aircraft the adjusting commands that are generated on the basis of the control commands depending on the acquired rotation rates said control function at least in some sections at the same time generates adjusting commands to the actuator of a rudder in order to at the same time in a period of time move at least one of the tail-mounted flaps and the rudder.

3. The aircraft according to claim 1 , wherein the control function is designed in such a manner that for lateral control of the aircraft the adjusting commands that are generated on the basis of the control commands depending on the acquired rotation rates, said control function at least in some sections at the same time generates adjusting commands to the actuator of at least one aileron and to the actuator of at least one spoiler in order to at the same time in a period of time move at least one of the tail-mounted flaps and at least one aileron and at least one spoiler so as to rotate the aircraft on its longitudinal axis.

4. The aircraft according to claim 1 , wherein the control function is designed in such a manner that for lateral control of the aircraft the adjusting commands that are generated on the basis of the control commands depending on the acquired rotation rates comprise adjusting commands to the actuator of the rudder and at least in some sections at the same time comprise adjusting commands to the actuator to both of the tail-mounted flaps for their actuation.

5. The aircraft according to claim 4 , wherein the deflection angle of the first tail-mounted flap that is situated on the side towards which the aircraft due to the control command is to turn is at least 10% greater than the deflection angle of the second tail-mounted flap.

6. The aircraft according to claim 1 , wherein in one operating mode the control function is designed in such a manner that for lateral control of the aircraft the adjusting commands for the actuators that are generated on the basis of the control commands and depending on the acquired rotation rates comprise adjusting commands to the actuator of the rudder and at least in some sections at the same time comprise adjusting commands to the actuator of one of the tail-mounted flaps for their actuation, in which adjusting commands in each case a tail-mounted flap is deflected symmetrically to the rudder in order to rotate the aircraft around its vertical axis.

7. The aircraft according to claim 1 , wherein the axes of rotation of the tail-mounted flaps are arranged behind the axis of rotation of the rudder in relation to the longitudinal axis of the aircraft.

8. The aircraft according to claim 1 , wherein the aircraft comprises an elevator, and wherein the tail-mounted flaps are arranged in such a manner that their axes of rotation extend behind the axis of rotation of the elevators in relation to the longitudinal axis of the aircraft.

9. The aircraft according to claim 1 , wherein the tail-mounted flaps are designed in such a manner that the exterior shells of the tail-mounted flaps, when viewed in circumferential direction of the fuselage, form a complete fuselage section when the tail-mounted flaps are in their stowed positions.

10. The aircraft according to claim 1 , wherein the aircraft comprises a tail-mounted engine arrangement, and wherein when viewed in longitudinal direction of the aircraft the tail-mounted flaps are arranged behind the engines that are arranged in the tail region and that are provided for propulsion of the aircraft.

11. The aircraft according to claim 10 , wherein for noise reduction during the landing approach the control function receives sensor values relating to the flight altitude of the aircraft, and comprises a function by means of which, as soon as the aircraft descends below a predetermined flight altitude, the control function generates and transmits adjusting commands to the actuators of the tail-mounted flaps, according to which control commands both tail-mounted flaps are extended to a predetermined minimum angle.

12. The aircraft according to claim 1 , wherein, in order to reduce the effects of wind gusts acting on the aircraft, the aircraft comprises:
a sensor device that is functionally connected with the control device, for acquiring wind gusts that act on the aircraft,
a wind-gust identification function for identifying wind gusts from the sensor values acquired by the sensor,
a control function which based on a determination by the wind-gust identification function that there is a wind gust transmits adjusting commands to the respective tail-mounted flaps in order to move them in such a way that the deflections of the respective tail-mounted flaps compensate for the effects which the wind gust has on the aircraft.

13. The aircraft according to claim 12 , wherein for identification of wind gusts the control function comprises:
a wind-gust identification function that is designed in such a manner that it determines any rise or change or increase in at least one of rotation rates and accelerations of the aircraft in a predetermined period of time,
a comparison function that compares any rise or change or increase in the rotation rate of the aircraft on its vertical axis in a predetermined period of time with a predetermined limit value, and, if this limit value is exceeded, identifies the presence of a wind gust in response to which a countermeasure needs to be ordered,

wherein the control function is designed in such a manner that based on the identification of a wind gust said control function determines adjusting commands c

Assignees

• Weber Carsten
• Fischer Markus
• Namer Arnaud
• Airbus Operations Gmbh
• Airbus Operations Sas

Inventors

• Weber Carsten
• Fischer Markus
• Namer Arnaud

Classifications

• B64C9/32

  Air braking surfaces · CPC title

• Y02T50/32

  Cross-Sectional Technologies · mapped topic

• B64C5/06 Primary

  Fins (B64C5/08 takes precedence) · CPC title

• Y02T50/30

  Wing lift efficiency · CPC title