Automatic pitch axis control system for aircraft

Claim 2

In combination in a pitch axis control system for an aircraft: glide slope error detector means; altitude above terrain detector means; first multiplier circuit means coupled to said glide slope error detector means and said altitude above terrain detector means for providing a first signal representative of actual flight path error of the aircraft; acceleration detector means; high pass filter circuit means coupled to said acceleration detector means; integrator circuit means responsive to said multiplier circuit means and said high pass filter circuit means for providing a second signal representative of the change in vertical velocity of the aircraft; ground velocity detector means; second multiplier circuit means coupled to said ground velocity detector means and said altitude above terrain detector means for providing a signal representative of commanded vertical velocity; and, means responsive to said first multiplier circuit means, said integrator circuit means, and said second multiplier circuit means for providing a signal representative of vertical velocity error.

Claim 3

In combination in a pitch axis control system for providing a signal representative of vertical velocity error at an output terminal for positioning an aircraft on a flight path to exponentially flare out onto a landing runway: acceleration detector means; high pass filter circuit means coupled to said acceleration detector means; integrator circuit means coupled to said pass filter circuit means for providing a first signal representative of the change in vertical velocity of said aircraft; altitude above terrain detector means; limiter circuit means coupled to said altitude above terrain detector means for providing a second signal representative of the desired flight path angle of said aircraft; ground velocity detector means; multiplier circuit means responsive to said second signal and coupled to said ground velocity detector means for providing a third signal representative of desired vertical velocity of said aircraft; and, means responsive to said integrator circuit means and said multiplier circuit means for providing a signal voltage representative of vertical velocity error.

Claim 4

In combination in a pitch axis control system for providing a signal representative of vertical velocity error at an output terminal for positioning an aircraft on a flight path to exponentially flare out onto a landing runway: acceleration detector means; high pass filter circuit means coupled to said acceleration detector means; integrator circuit means coupled to said pass filter circuit means for providing a first signal representative of the change in vertical velocity of said aircraft; altitude above terrain detector means; limiter circuit means coupled to said altitude above terrain detector means for providing a second signal representative of the desired flight path angle of said aircraft; ground velocity detector means; multiplier circuit means responsive to said second signal and coupled to said ground velocity detector means for providing a third signal representative of desired vertical velocity of said aircraft; and, means responsive to said integrator circuit means and said multiplier circuit means for providing a signal voltage representative of vertical velocity error.

Claim 5

A pitch axis control system for providing a signal representative of a flight path command at the system output terminal thereof comprising in combination: glide slope error detector means; glide slope gain multiplier circuit means; first adder circuit means; amplifier circuit means; said glide slope gain multiplier circuit means and said first adder circuit means coupled between said glide slope error detector means and the input terminal of said amplifier means, the output terminal of said amplifier means coupled to said system output terminal; control surface feedback measuring means coupled between the control surfaces and said first adder circuit meanS; second adder circuit means coupled to said glide slope gain multiplier circuit means; integrator circuit means; said integrator circuit means input coupled to said second adder circuit means and said integrator circuit means output coupled to said first adder circuit means; vertical acceleration detector means; high pass filter circuit means; said high pass filter circuit means coupled between said vertical acceleration detector means and said second adder circuit means; ground velocity detector means; vertical velocity command multiplier circuit means; altitude above terrain detector means; flight path angle command signal generating means including limiter circuit means coupled between said altitude above terrain detector means and said vertical velocity command multiplier circuit means; and said vertical velocity command multiplier circuit means coupled between said ground velocity detector circuit means and said first adder circuit means.

Claim 6

A pitch axis control system for providing a signal representative of a flight path command at the system output terminal thereof comprising in combination: glide slope error detector means; glide slope gain multiplier circuit means; first adder circuit means; amplifier circuit means; said glide slope gain multiplier circuit means and said first adder circuit means coupled between said glide slope error detector means and the input terminal of said amplifier means, the output terminal of said amplifier means coupled to said system output terminal; control surface feedback measuring means coupled between the control surfaces and said first adder circuit meanS; second adder circuit means coupled to said glide slope gain multiplier circuit means; integrator circuit means; said integrator circuit means input coupled to said second adder circuit means and said integrator circuit means output coupled to said first adder circuit means; vertical acceleration detector means; high pass filter circuit means; said high pass filter circuit means coupled between said vertical acceleration detector means and said second adder circuit means; ground velocity detector means; vertical velocity command multiplier circuit means; altitude above terrain detector means; flight path angle command signal generating means including limiter circuit means coupled between said altitude above terrain detector means and said vertical velocity command multiplier circuit means; and said vertical velocity command multiplier circuit means coupled between said ground velocity detector circuit means and said first adder circuit means.

Claim 7

The invention according to claim 3 further comprising low pass filter circuit means coupled between said high pass filter circuit means and said first adder circuit.

Claim 8

The invention according to claim 4 further comprising pitch rate detector means and band pass filter circuit means coupled in series circuit path with said first adder circuit.

Claim 9

An aircraft pitch axis control system for providing pitch axis control signals at the system output terminal thereof comprising in combination: first circuit means for providing a first signal representative of vertical acceleration of said aircraft; high pass filter circuit means responsive to said first signal for providing a second signal; second circuit means for combining a plurality of input signals at the input terminals thereof and providing an output signal at an output terminal thereof; third circuit means for providing a third signal representative of glide slope error of said aircraft; first gain controlled amplifier circuit means responsive to said third circuit means for providing a fourth signal, and means for coupling said second and fourth signals respectively to said input terminals of said second circuit means; third circuit means for combining a plurality of input signals at the input terminals thereof and providing an output signal at an output terminal thereof, and means for coupling said output terminal to said system output terminal; fourth circuit means for coupling said fourth signal to a first of said plurality of input terminals of said third circuit means; a first series circuit path including low pass filter circuit means responsive to said second signal and coupled to a second of said plurality of input terminals of said third circuit means; fifth circuit means for providing a fifth signal representative of altitude above terrain of said aircraft; a limiter circuit; second gain controlled amplifier circuit means; sixth circuit means for combining a plurality of input signals including said fifth signal and a bias voltage at respective input terminals thereof and providing an output signal at an output terminal thereof, and means for coupling said output terminal, said limiter circuit and said second gain controlled amplifier circuit means in series circuit path with a third of said plurality of input terminals of said third circuit means; seventh circuit means for providing a sixth signal representative of ground velocity of said aircraft, said fifth and seventh signals coupled respectively to said first and second gain controlled amplifiers for controlling the respective gains thereof; eighth circuit means for providing a seventh signal representative of pitch rate of said aircraft; means including band pass filter circuit means coupled between said eighth circuit means and a fourth of said plurality of input terminals of said third circuit means; integrator circuit means having an input terminal and an outpuT terminal, said output terminal coupled to a fifth of said plurality of input terminals of said third circuit means; switching means for coupling said input terminal of said integrator circuit to said output terminal of said second circuit means or completing a series circuit path including amplifier circuit means to said system output terminal.

Claim 10

An aircraft pitch axis control system for providing pitch axis control signals at the system output terminal thereof comprising in combination: first circuit means for providing a first signal representative of vertical acceleration of said aircraft; high pass filter circuit means responsive to said first signal for providing a second signal; second circuit means for combining a plurality of input signals at the input terminals thereof and providing an output signal at an output terminal thereof; third circuit means for providing a third signal representative of glide slope error of said aircraft; first gain controlled amplifier circuit means responsive to said third circuit means for providing a fourth signal, and means for coupling said second and fourth signals respectively to said input terminals of said second circuit means; third circuit means for combining a plurality of input signals at the input terminals thereof and providing an output signal at an output terminal thereof, and means for coupling said output terminal to said system output terminal; fourth circuit means for coupling said fourth signal to a first of said plurality of input terminals of said third circuit means; a first series circuit path including low pass filter circuit means responsive to said second signal and coupled to a second of said plurality of input terminals of said third circuit means; fifth circuit means for providing a fifth signal representative of altitude above terrain of said aircraft; a limiter circuit; second gain controlled amplifier circuit means; sixth circuit means for combining a plurality of input signals including said fifth signal and a bias voltage at respective input terminals thereof and providing an output signal at an output terminal thereof, and means for coupling said output terminal, said limiter circuit and said second gain controlled amplifier circuit means in series circuit path with a third of said plurality of input terminals of said third circuit means; seventh circuit means for providing a sixth signal representative of ground velocity of said aircraft, said fifth and seventh signals coupled respectively to said first and second gain controlled amplifiers for controlling the respective gains thereof; eighth circuit means for providing a seventh signal representative of pitch rate of said aircraft; means including band pass filter circuit means coupled between said eighth circuit means and a fourth of said plurality of input terminals of said third circuit means; integrator circuit means having an input terminal and an outpuT terminal, said output terminal coupled to a fifth of said plurality of input terminals of said third circuit means; switching means for coupling said input terminal of said integrator circuit to said output terminal of said second circuit means or completing a series circuit path including amplifier circuit means to said system output terminal.