Aircraft instrument

Claim 2

An aircraft instrument comprising: means establishing a desired aircraft flight condition; means measuring the actual aircraft flight condition; means connected with said establishing and measuring means for comparing the desired and actual flight condition to determine the error in the flight condition and establishing a command representative thereof; means establishing a composite damping signal for said error command, including a source of long term damping information, a source of short term damping information and means connected with said sources for combining the long term and short term damping information; and means connected with said comparing and said damping signal establishing means, combining the composite damping signal with the error command.

Claim 3

The aircraft instrument of claim 1 in which said damping signal establishing means includes a complementary filter connected with the sources of long and short term damping information and a summing means is connected with the filter.

Claim 4

The aircraft instrument of claim 2 in which the complementary filter includes a low pass filter connected with the source of long term damping information and a high pass filter connected with the source of short term damping information, with said summing means combining the outputs of the filters.

Claim 5

The aircraft instrument of claim 1 in which the source of short term damping information is a longitudinal accelerometer.

Claim 6

The aircraft instrument of claim 1 for a movable aircraft having an elevator surface and in which the source of short term damping information is a means responsive to the angle of said elevator surface.

Claim 7

The aircraft instrument of claim 1 in which the source of long term damping information includes a means responsive to the angle of attack of the aircraft, means responsive to normal acceleration of the aircraft each havinG an output, and means connected therewith for combining the angle of attack and normal acceleration outputs.

Claim 8

The aircraft instrument of claim 6 in which the means for combining the angle of attack and normal acceleration information includes means for establishing a signal which is the ratio of signals representing the angle of attack and normal acceleration of the aircraft.

Claim 9

The aircraft instrument of claim 7 including means, connected with said signal ratio-establishing means, for differentiating the signal which represents the ratio of angle of attack and normal acceleration signals.

Claim 10

The aircraft instrument of claim 7 in which the angle of attack signal is the numerator and the normal acceleration signal is the denominator of the ratio.

Claim 11

The aircraft instrument of claim 7 in which the normal acceleration signal is the numerator and the angle of attack signal is the denominator of the ratio.

Claim 12

The aircraft instrument of claim 7 including means, connected with said signal ratio-establishing means, for obtaining the square root of the ratio between the angle of attack and normal acceleration signals.

Claim 13

The aircraft instrument of claim 6, for an aircraft having flaps and slats, in which the source of angle of attack information includes means establishing a programmed angle of attack as a function of the positions of the flaps and slats and means connected therewith for comparing the programmed angle of attack with the actual angle of attack to obtain a signal representing an angle of attack error.

Claim 14

The aircraft instrument of claim 6 in which the source of long term damping information includes means for differentiating the angle of attack and normal acceleration information, the instrument further including means connected with said differentiating means and one of said angle of attack or normal acceleration responsive means, combining the differentiated information with an output representing at least one of the angle of attack or normal acceleration.

Claim 15

The aircraft instrument of claim 13 in which said last-mentioned combining means is connected with both said angle of attack and normal acceleration responsive means, combining the differentiated information with both angle of attack and normal acceleration information.

Claim 16

The aircraft instrument of claim 6 in which the means responsive to angle of attack includes means establishing a programmed angle of attack and for comparing it with the angle of attack of the aircraft to obtain a signal representing an angle of attack error, means for combining the output of the normal acceleration responsive means with the angle of attack error signal and for differentiating the combination, and means connected with said differentiating means and one of said angle of attack or normal acceleration responsive means, for combining the differentiated information with an output representing at least one of the angle of attack and normal acceleration information.

Claim 17

An aircraft instrument, for an aircraft having flaps and slats, comprising: means establishing a signal representing a desired aircraft angle of attack as a function of flap and slat positions; means establishing a signal representing the actual aircraft angle of attack; means connected with said signal-establishing means for comparing the desired and actual angle of attack signals and establishing a signal representing the angle of attack error; means establishing a composite damping signal for said error signal, including a source of signal representing long term damping information, a source of signal representing short term damping information and a complementary filter with summing means for combining the long and short term damping information signals; and means connected with said comparing and said damping signal establishing means, combining the composite damping signal with the error signal.

Claim 18

An aircraft instrument, for an aircraft having flaps and slats, comprising: means establishing a signal representing a desired aircraft angle of attack as a function of flap and slat positions; means establishing a signal representing the actual aircraft angle of attack; means connected with said signal-establishing means for comparing the desired and actual angle of attack signals and establishing a signal representing the angle of attack error; means establishing a composite damping signal for said error signal, including a source of signal representing long term damping information, a source of signal representing short term damping information and a complementary filter with summing means for combining the long and short term damping information signals; and means connected with said comparing and said damping signal establishing means, combining the composite damping signal with the error signal.

Claim 19

The aircraft instrument of claim 16 in which the source of long term dampinG information includes a source of angle of attack information for the aircraft, a source of normal acceleration information for the aircraft, each having an output and means for combining the angle of attack and normal acceleration outputs.

Claim 20

The aircraft instrument of claim 17 in which the source of short term damping information is an accelerometer responsive to the longitudinal acceleration of the aircraft.

Claim 21

The aircraft instrument of claim 17 for an aircraft having a movable elevator surface and in which the source of short term damping information is means responsive to the angle of the elevator surface.

Claim 22

The aircraft instrument of claim 17 in which the source of long term damping information includes means for obtaining a signal representing the ratio of the outputs of an angle of attack error signal to a normal acceleration signal and means connected thereto for differentiating the ratio signal.

Claim 23

The aircraft instrument of claim 20 in which the source of long term damping information includes means for differentiating the angle of attack and normal acceleration ratio signal, the instrument further including means connected therewith combining the differentiated signal with an output representing at least one of the angle of attack or normal acceleration.