Automatic approach landing and go-around roll axis control system for aircraft

Claim 2

In combination in an aircraft having a roll axis control system and having an output terminal: first means coupled to said output terminal for storing a constant signal representative of commanded ground track error; second means coupled to said output terminal for generating a further signal representative of change in ground track thereby providing a signal to null or cancel said commanded ground track error signal or providing ground track referenced control during go-around,; and wherein said first means comprises: sensor means providing a signal representative of aircraft ground track error; integrator circuit means connected in feedback circuit around said output terminal; second switching means connected in series circuit between said sensor means and said control system output terminal; third switching means connected in series circuit between said control system output terminal and said integrator circuit means and switching simultaneously with said second switching means.

Claim 3

In combination in an aircraft roll axis control system comprising: first means including roll attitude signal generating means, and second means for generating signals representative of lateral acceleration of said aircraft; third means comprising an adder circuit for combining said signal representative of lateral acceleration of said aircraft, including that portion of said roll attitude signal and said lateral acceleration signal representative of steady state null errors for providing a third signal representative of airplane ground track rate in combination with said sensor steady state null errors; fourth means comprising a further adder circuit connected to said third means for providing signals representative of dynamic ground track rate at the output of said further adder circuit means and having integrator circuit means coupled in feedback circuit around said further adder circuit, and further including switching means connected in series circuit between said integrator circuit means and said further adder circuit means, and operative to provide an open circuit during aircraft lateral manuevers thereby causing said integrator circuit means to store a signal representative of said steady state null errors; and utilization means comprising control surface actuator means responsive to said signal representative of airplane dynamic ground track rate coupled between said further adder circuit means and the control surface means of said aircraft.

Claim 4

In combination in an aircraft roll axis control system comprising: first means including roll attitude signal generating means, and second means for generating signals representative of lateral acceleration of said aircraft; third means comprising an adder circuit for combining said signal representative of lateral acceleration of said aircraft, including that portion of said roll attitude signal and said lateral acceleration signal representative of steady state null errors for providing a third signal representative of airplane ground track rate in combination with said sensor steady state null errors; fourth means comprising a further adder circuit connected to said third means for providing signals representative of dynamic ground track rate at the output of said further adder circuit means and having integrator circuit means coupled in feedback circuit around said further adder circuit, and further including switching means connected in series circuit between said integrator circuit means and said further adder circuit means, and operative to provide an open circuit during aircraft lateral manuevers thereby causing said integrator circuit means to store a signal representative of said steady state null errors; and utilization means comprising control surface actuator means responsive to said signal representative of airplane dynamic ground track rate coupled between said further adder circuit means and the control surface means of said aircraft.

Claim 5

In combination in a roll axis control system for an aircraft: first means for generating a first signal representative of deviation from aircraft flight path; second means for producing a second signal referenced to the aircraft ground track rate; third means comprising lag filter circuit means coupled to said second means for producing a third signal representative of change in aircraft ground track; fourth means for combining said first signal and said third signal to null or cancel said first signal; and fifth means including lateral control actuator means coupled between said fourth means and the control surfaces of said aircraft.

Claim 6

In combination in a roll axis control system for an aircraft: first means for generating a first signal representative of deviation from aircraft flight path; second means for producing a second signal referenced to the aircraft ground track rate; third means comprising lag filter circuit means coupled to said second means for producing a third signal representative of change in aircraft ground track; fourth means for combining said first signal and said third signal to null or cancel said first signal; and fifth means including lateral control actuator means coupled between said fourth means and the control surfaces of said aircraft.

Claim 7

The invention according to claim 3 wherein said second means comprises: an accelerometer arranged in said aircraft and having the sensing axis thereof disposed parallel to the lateral axis of said aircraft; a roll attitude signal source; and means for combining the outputs of said accelerometer and roll attitude signal source to provide said second signal.

Claim 8

A roll axis control system for providing a flight path command signal at the system output terminal comprising in combination: localizer error detector means; first lag filter circuit means; decreasing gain programmer circuit means; first adder circuit means; amplifier circuit means; said first lag filter circuit means, said decreasing gain programmer circuit means, said first adder circuit means and said amplifier circuit means connected in series circuit between said localizer error detector means and the system output terminal; localizer integrator circuit means and first increasing gain programmer circuit means coupled in series circuit between said first adder circuit means and said output terminal; means for generating a signal representative of aircraft dynamic ground track rate, second increasing gain programmer circuit means and second lag filter circuit means coupled in series circuit between said means for generating a signal representative of airplane dynamic ground track rate and said first adder circuit means; surface feedback measuring means; first means coupling said surface feedback means between the control surfaces and said system output terminal; altitude above terrain detector means for providing said increasing and decreasing gain programmer circuit means; roll attitude signal generating means; said roll attitude signal generating means connected to said first adder means; roll rate signal generating means; and third lag filter circuit means coupled in series circuit between said roll rate signal generating means and said first adder circuit means.

Claim 9

A roll axis control system for providing a flight path command signal at the system output terminal comprising in combination: localizer error detector means; first lag filter circuit means; decreasing gain programmer circuit means; first adder circuit means; amplifier circuit means; said first lag filter circuit means, said decreasing gain programmer circuit means, said first adder circuit means and said amplifier circuit means connected in series circuit between said localizer error detector means and the system output terminal; localizer integrator circuit means and first increasing gain programmer circuit means coupled in series circuit between said first adder circuit means and said output terminal; means for generating a signal representative of aircraft dynamic ground track rate, second increasing gain programmer circuit means and second lag filter circuit means coupled in series circuit between said means for generating a signal representative of airplane dynamic ground track rate and said first adder circuit means; surface feedback measuring means; first means coupling said surface feedback means between the control surfaces and said system output terminal; altitude above terrain detector means for providing said increasing and decreasing gain programmer circuit means; roll attitude signal generating means; said roll attitude signal generating means connected to said first adder means; roll rate signal generating means; and third lag filter circuit means coupled in series circuit between said roll rate signal generating means and said first adder circuit means.

Claim 10

The invention according to claim 5 further comprising: means for generating a signal representative of aircraft lateral acceleration; adder circuit means for combining the signals from said means for generating a signal representative of aircraft lateral acceleration and said roll attitude signal generating means thereby generating a signal representative of aircraft ground track rate, further adder circuit means connected to the output of said adder circuit means to generate a signal representative of aircraft dynamic ground track rate, integrator circuit means connected in feedback circuit around said further adder circuit.

Claim 11

The invention according to claim 5 further comprising: first switching means connected in series-circuit between said localizer integrator circuit means and said amplifier output terminal and operative to provide an open circuit upon control actuation and simultaneously provide a closed circuit between said localizer integrator circuit means and said first lag filter circuit means output thereby storing a constant signal at said integrator circuit means output representative of initial localizer error and actual airplane ground track upon control actuation, the said constant signal further representative of a ground track command to cause the aircraft to manuever so as to exponentially acquire localizer beam center; and, second switching means connected in series circuit between said means for generating a signal representative of aircraft dynamic ground track rate and said second increasing gain programmer circuit means, and operative simultaneously with said first switching means.

Claim 12

The invention according to claim 5 further comprising switching means coupled in series circuit between said localizer error detector means and said first lag filter circuit means and operative during automatic go-around to provide an open circuit thereby decoupling said localizer error detector means and providing automatic go-around control referenced to aircraft ground track.

Claim 13

The invention according to claim 5 further comprising means in said first lag filter circuit means for providing a limited maximum roll command for coupling with said decreasing gain programmer circuit means to automatically decrease said maximum roll command limit for flare manuever.

Claim 14

A roll axis control system for providing a flight path command signal at the system output terminal comprising in combination: means for generating a signal representative of aircraft dynamic ground track rate; first lag filter circuit means; adder circuit means; amplifier circuit means; said first lag filter circuit means and adder circuit means coupled in series circuit between said means for generating a signal representative of aircraft dynamic ground track rate and said amplifier circuit means, said amplifier circuit means connected to the control system output terminal; means for storing a constant signal representative of actual aircraft ground track error upon initiation of automatic control coupled to said adder circuit means; surface feedback measuring means; first means coupling said surface feedback means between the control surfaces and said system output terminal; roll attitude signal generating means connected to said adder circuit means; roll rate signal generating means; and, second lag filter circuit means connected in series circuit between said roll rate signal generating means and said adder circuit means.

Claim 15

A roll axis control system for providing a flight path command signal at the system output terminal comprising in combination: means for generating a signal representative of aircraft dynamic ground track rate; first lag filter circuit means; adder circuit means; amplifier circuit means; said first lag filter circuit means and adder circuit means coupled in series circuit between said means for generating a signal representative of aircraft dynamic ground track rate and said amplifier circuit means, said amplifier circuit means connected to the control system output terminal; means for storing a constant signal representative of actual aircraft ground track error upon initiation of automatic control coupled to said adder circuit means; surface feedback measuring means; first means coupling said surface feedback means between the control surfaces and said system output terminal; roll attitude signal generating means connected to said adder circuit means; roll rate signal generating means; and, second lag filter circuit means connected in series circuit between said roll rate signal generating means and said adder circuit means.

Claim 16

In combination in an aircraft having a roll axis control system: first means for generating a programmed disturbance of the aircraft laterally away from the intended flight path for testing integrity of the system; said first means comprising means including a voltage shaping circuit; said first means actuated by logic control signals, said logic control signals responsive to roll axis control signals of said control system; said means including a voltage shaping circuit providing a signal voltage coupled to said control system for disturbing the aircraft away from the flight path and subsequently reducing the amplitude of said signal voltage thereby providing control system commands for re-acquiring the localizer zero plane upon generation of input signals by all sensors and respective signal shaping paths of said sensors.

Claim 17

In combination in an aircraft having a roll axis control system: first means for generating a programmed disturbance of the aircraft laterally away from the intended flight path for testing integrity of the system; said first means comprising means including a voltage shaping circuit; said first means actuated by logic control signals, said logic control signals responsive to roll axis control signals of said control system; said means including a voltage shaping circuit providing a signal voltage coupled to said control system for disturbing the aircraft away from the flight path and subsequently reducing the amplitude of said signal voltage thereby providing control system commands for re-acquiring the localizer zero plane upon generation of input signals by all sensors and respective signal shaping paths of said sensors.

Claim 18

In combination in an aircraft having a roll axis control system and having an output terminal: first means coupled to said output terminal for storing a constant signal representative of commanded ground track error; second means coupled to said output terminal for generating a further signal representative of change in ground track thereby providing a signal to null or cancel said commanded ground track error signal for providing ground track referenced control during go-around; said second means comprising: an accelerometer disposed in the body of the aircraft having the sensing axis parallel to the aircraft lateral axis, a roll attitude sensor, adder circuit means for combining the respective signals of said accelerometer and said roll attitude sensor thereby generating a third signal representative of aircraft ground track rate, lag filter circuit means connected in series circuit with said adder circuit means for providing psuedo-integration of said third signal thereby generating said further signal, and first switching means connected in series circuit between said adder circuit means and said lag filter circuit means.

Claim 19

In combination in an aircraft having a roll axis control system and having an output terminal: first means coupled to said output terminal for storing a constant signal representative of commanded ground track error; second means coupled to said output terminal for generating a further signal representative of change in ground track thereby providing a signal to null or cancel said commanded ground track error signal for providing ground track referenced control during go-around; said second means comprising: an accelerometer disposed in the body of the aircraft having the sensing axis parallel to the aircraft lateral axis, a roll attitude sensor, adder circuit means for combining the respective signals of said accelerometer and said roll attitude sensor thereby generating a third signal representative of aircraft ground track rate, lag filter circuit means connected in series circuit with said adder circuit means for providing psuedo-integration of said third signal thereby generating said further signal, and first switching means connected in series circuit between said adder circuit means and said lag filter circuit means.

Claim 20

The invention according to claim 12 wherein said second means further comprises gain programming means connected in series circuit between said first switching means and said lag filter circuit means for providing variable damping during automatic go-around control.