Flight control system and method with track maintenance for a rotary wing aircraft

Patent metadata

Field	Value
Publication number	US-9682768-B2
Application number	US-201514750726-A
Country	US
Kind code	B2
Filing date	Jun 25, 2015
Priority date	Jun 30, 2014
Publication date	Jun 20, 2017
Grant date	Jun 20, 2017

Abstract

A flight control system for a rotary wing aircraft, the aircraft following a track T sol , relative to the ground with a ground course angle TK sol , a forward speed Va, a flight path angle P, and a heading Ψ, the aircraft having one or more rotary wings provided with blades of collective pitch and of cyclic pitch that are variable about respective pitch axes and that are capable of performing movements in rotation and in translation. The flight control system has two control members each provided respectively with at least one movement axis A, B, C, D, and an autopilot for generating control signals. An action on one of the control members relative to one of the movement axes A, B, C, D gives rise independently to a modification to the forward speed Va, to the ground course angle TK sol , or indeed to the flight path angle P by means of the autopilot.

First claim

What is claimed is:

1. A flight control system for a rotary wing aircraft, the aircraft flying while maintaining track T sol relative to the ground with a ground course angle TK sol , a forward speed Va, a flight path angle P, and a heading Ψ, a longitudinal direction X extending from the rear of the aircraft to the front of the aircraft, an elevation direction Z extending upwards perpendicularly to the longitudinal direction X, and a transverse direction Y extending from left to right perpendicularly to the longitudinal and elevation directions X and Z,
the aircraft having at least one rotary wing provided with a plurality of main blades having collective pitch and cyclic pitch that are variable about respective pitch axes, the aircraft being capable of performing movements in rotation about the directions X, Y, Z and in translation along the directions X, Y, Z; and
the flight control system comprising:
at least one control member provided jointly with a plurality of movement axes A, B, C, D; and
an autopilot generating control signals in compliance with predefined modes of operation and in compliance with flight setpoints, the control signals being capable of causing the aircraft to perform the movements in rotation and/or translation relative to the directions X, Y, Z;

wherein:
at least one control member is movable relative to a first movement axis A in order to lead to a modification in the forward speed Va independently of the ground course angle TK sol and of the flight path angle P by taking a first action relative to the first movement axis A and by means of the autopilot;
the at least one control member is movable relative to a second movement axis B in order to cause a modification to the ground course angle TK sol independently of the forward speed Va and of the flight path angle P by taking a second action relative to the movement axis B and by means of the autopilot; and
the at least one control member is movable relative to a third movement axis C to cause a modification to the flight path angle P independently of the ground course angle TK sol and of the forward speed Va by taking a third action relative to the third movement axis C and by means of the autopilot.

2. A flight control system for a rotary wing aircraft according to claim 1 , wherein the at least one control member is movable relative to a fourth movement axis D in order to give to a modification of the ground course angle TK sol by taking a fourth action relative to the fourth axis D and by means of the autopilot.

3. A flight control system for a rotary wing aircraft according to claim 1 , wherein the ground course angle TK sol , the forward speed Va, and the flight path angle P of the aircraft are aligned as new setpoints for the autopilot on each occasion action is taken on the at least one control member.

4. A flight control system for a rotary wing aircraft according to claim 1 , wherein the aircraft has a first control lever enabling movements of the aircraft in rotation about the longitudinal and transverse directions X and Y to be controlled, a second control lever enabling movements of the aircraft in translation along the elevation direction Z to be controlled in a first secondary mode of operation of the flight control system, the first control member is the first control lever and the second control member is the second control lever, the first control member having the first movement axis A and the second movement axis B, and the second control member having the third movement axis C.

5. A flight control system for a rotary wing aircraft according to claim 1 , wherein the aircraft has a first control lever enabling movements in translation of the aircraft about the longitudinal and transverse directions X and Y to be controlled and a second control lever enabling movements in translation of the aircraft along the elevation direction Z to be controlled, a first control member is positioned on the first control lever, and a second control member is positioned on the second control lever, the first control member including the first movement axis A and the second movement axis B, and the second control lever including the third movement axis C.

6. A flight control system for a rotary wing aircraft according to claim 5 , wherein the second control member includes a fourth movement axis D.

7. A flight control system for a rotary wing aircraft according to claim 5 , wherein in a second secondary mode of operation of the flight control system, at least one flight control member can control the movements in rotation of the aircraft about the longitudinal and transverse directions X and Y and also the movements in translation of the aircraft along the elevation direction Z.

8. A flight control system for a rotary wing aircraft according to claim 4 , wherein a violent action on the first control lever causes the autopilot to cease maintaining the setpoints for the flight path angle P, the first control lever controlling movements in rotation of the aircraft about the longitudinal and transverse directions X and Y and the second control lever controlling movements in translation of the aircraft along the elevation direction Z.

9. A flight control system for a rotary wing aircraft according to claim 1 , wherein the control members are calibrated and control precise movements of the aircraft.

10. A flight control system for a rotary wing aircraft according to claim 1 , wherein the forward speed Va is the forward speed of the aircraft relative to the ground.

11. A flight control system for a rotary wing aircraft according to claim 1 , wherein the forward speed Va is the forward speed of the aircraft relative to the air.

12. A flight control system for a rotary wing aircraft according to claim 1 , wherein if the forward speed Va is less than a certain forward speed, the flight path angle P is replaced by the vertical speed W Z .

13. A flight control system for a rotary wing aircraft according to claim 12 , wherein the certain forward speed is equal to 20 kt.

14. A flight control method for a rotary wing aircraft, the aircraft flying to maintain a track T sol relative to the ground with a ground course angle TK sol , a forward speed Va, a flight path angle P, and a heading Ψ, a longitudinal direction X being from the rear of the aircraft to the front of the aircraft, an elevation direction Z extending upwards perpendicularly to the longitudinal direction X, and a transverse direction Y extending from left to right perpendicularly to the longitudinal and elevation directions X and Z, the aircraft comprising:
at least one rotary wing provided with a plurality of main blades of collective pitch and cyclic pitch that are variable about respective pitch axes, the aircraft being capable of performing movements in rotation about the directions X, Y, Z and in translation along the directions X, Y, Z;
an autopilot generating control signals in compliance with predefined modes of operation and in compliance with flight setpoints, the control signals being capable of causing the aircraft to perform the movements in rotation and/or translation relative to the directions X, Y, Z; and
a flight control system including at least one control member provided jointly with a plurality of movement axes A, B, C, D;
the method comprising the following steps:
controlling a modification to the forward speed Va by taking a first action relative to a first movement axis A of a control member and by means of the autopilot;
controlling a modification to the ground course angle TK sol by taking a second action relative to a second movement axis B of a control member and by means of the

Assignees

• Airbus Helicopters

Inventors

• Salesse-Lavergne Marc

Classifications

• B64C27/04

  Helicopters · CPC title

• B64C13/18 Primary

  using automatic pilot · CPC title

• G05D1/0858 Primary

  specially adapted for vertical take-off of aircraft · CPC title