US3691356A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Speed command and throttle control system for aircraft
Assignee: Honeywell Inc
•
Filing: 1970-12-10
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Granted: 1972-09-12
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Expires: 1990-12-10
Abstract
Abstract Aircraft control apparatus for providing pitch guidance to the pilot during the takeoff acceleration phase between rotation airspeed and steady climbing speed in accordance with Federal Airworthiness Standards for takeoff safety speeds. The steady climbing target speed is determined from computed values of actual coefficient of lift of the aircraft compared to a reference value of coefficient of lift which is programmed in accordance with the number of operating engines, existing thrust to weight ratio, flap position, and leading edge slat extension. The pitch guidance is derived from a control equation which generates a regulating signal for driving the pitch command pointer of an attitude flight director display. Pitch guidance is provided for the pushover acceleration mode during which the aircraft''s takeoff flap-slat configuration is retracted and the aircraft is stabilized on a new climb path at a preset airspeed. Pitch guidance is also provided for a missed approach procedure. Further provision is made for the automatic or manual control of engine throttles to maintain an optimum thrust condition or to maintain a pilot set airspeed, including override means whereby a minimum safe speed based on flap position and computed gross weight will override the selected speed if it is below the computed minimum. An additional override is provided to inhibit pilot selection of airspeeds which are above structural limitations of the flaps. The system requires speed control parameters which are computed by apparatus which provides a measure of the angle of attack and coefficient of lift of an aircraft without external probes or vanes, which measure is derived from computations involving measurements of aircraft longitudinal acceleration, normal acceleration, vertical speed, calibrated airspeed, Mach number, and positions of the movable aerodynamic surfaces which affect the coefficient of lift of an airplane. Supplementary outputs of the computer are signals proportional to acceleration along the flight path, thrust over weight ratio, gross weight of the airplane, potential flight path angle of the airplane, and actual flight path angle.
Inventors
- 👤 Harry Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:56
CPC Classifications
G; G06; G06G; G06G7/00; G06G7/48; G06G7/78; G05; G05D; G05D1/00; G05D1/04; G05D1/06; G05D1/0607; G05D1/0653; G05D1/0661; G06G7/70
Claims Analysis
Total Claims: 38
Claim 1
Independent Claim
117 words
Apparatus by means of which an aircraft may be controlled during take-off to approach and thereafter maintain an airspeed consistent with a safe stall margin, obstacle clearance, and climb gradient, comprising first computer means for providing a first signal corresponding to a reference coefficient of lift of said aircraft said reference coefficient of lift corresponding to said airspeed, second computer means for providing a second signal corresponding to the actual coefficient of lift of said aircraft, second computer means for providing a third signal corresponding to the acceleration of the aircraft along its flight path, and means connected to receive said first, second and third signals for supplying an output signal corresponding to the algebraic sum thereof.
Claim 2
Dependent Claim
117 words
Apparatus by means of which an aircraft may be controlled during take-off to approach and thereafter maintain an airspeed consistent with a safe stall margin, obstacle clearance, and climb gradient, comprising first computer means for providing a first signal corresponding to a reference coefficient of lift of said aircraft said reference coefficient of lift corresponding to said airspeed, second computer means for providing a second signal corresponding to the actual coefficient of lift of said aircraft, second computer means for providing a third signal corresponding to the acceleration of the aircraft along its flight path, and means connected to receive said first, second and third signals for supplying an output signal corresponding to the algebraic sum thereof.
Claim 3
Dependent Claim
50 words
The apparatus as set forth in claim 1 wherein said first computer means includes, further computer means for producing a signal proportional to the thrust-over-weight ratio of said aircraft, and means responsive to said thrust-over-weight ratio signal for modifying said reference coefficient of lift signal as a predetermined function thereof.
Claim 4
Dependent Claim
40 words
The apparatus as set forth in claim 2 for aircraft equipped with multiple engines wherein said first computer means includes a means responsive to the loss of one of said engines for further modifying the value of said first signal.
Claim 5
Dependent Claim
146 words
The apparatus as set forth in claim 2 wherein said further computer means comprises means for providing signals proportional respectively to components of acceleration of said aircraft along its longitudinal and normal axes, means for providing a signal proportional to the angle of attack of said aircraft, means responsive to the difference between said longitudinal axis acceleration signal and the product of said normal axis acceleration and angle of attack signals for providing a signal corresponding to thrust minus drag over weight ratio signal and said lift over weight ratio of said aircraft, means responsive to said normal acceleration and said angle of attack signal for providing a signal corresponding to the lift over weight ratio of said aircraft, and means responsive to said thrust minus drag over weight ratio signal and said lift over weight ratio signal for providing said thrust over weight ratio signal.
Claim 6
Dependent Claim
56 words
The apparatus as set forth in claim 1 for aircraft equipped with moveable surfaces for varying the lift characteristics of said aircraft wherein said first computer means includes a function generator means responsive to the positions of said moveable surfaces for modifying said first signal in accordance with a predetermined function of said moveable surface positions.
Claim 7
Dependent Claim
68 words
The apparatus as set forth in claim 1 for aircraft equipped with moveable control surfaces for varying the lift characteristics of said aircraft when said surfaces are deflected wherein said second computer means includes means for supplying a signal proportional to the angle of attack of said aircraft, and means responsive to the deflection of said control surfaces for modifying said angle of attack signal in accordance therewith.
Claim 8
Dependent Claim
71 words
The apparatus as set forth in claim 6 for aircraft wherein said control surfaces include moveable tail surfaces for adjusting forces on the aircraft in its longitudinal plane and wherein said last mentioned means includes means responsive to the deflection of said tail surfaces for further modifying said angle of attack signal whereby to compensate said actual coefficient of lift signal for shifts in the center of gravity of said aircraft.
Claim 9
Dependent Claim
43 words
The apparatus as set forth in claim 1 further including utilization apparatus for commanding a pitch attitude of said aircraft, and means for supplying said output signal to said utilization apparatus whereby to command a pitch attitude of said aircraft in accordance therewith.
Claim 10
Dependent Claim
70 words
The apparatus as set forth in claim 8 further including means for supplying a signal corresponding to the pitch attitude of said aircraft, means for supplying said pitch attitude signal to said utilization apparatus, and means for limiting the maximum value of said pitch attitude signal supplied to said utilization apparatus whereby to limit the maximum pitch attitude command of said craft when controlled in accordance with said utilization apparatus.
Claim 11
Dependent Claim
59 words
The apparatus as set forth in claim 9 further including, means responsive to said pitch attitude signal for deriving a signal proportional to the rate of change thereof, and means for supplying said pitch rate signal to said utilization apparatus whereby to inhibit oscillations of the pitch attitude of said aircraft when controlled in accordance with said utilization apparatus.
Claim 12
Dependent Claim
122 words
In an airspeed control system for aircraft, apparatus for supplying a signal representative of thrust minus drag over weight ratio comprising accelerometer means for providing first and second signals proportional respectively to the components of acceleration of said aircraft along its longitudinal and normal axes, means providing a third signal proportional to the angle of attack of said aircraft, means for supplying an output signal in accordance with the difference between said first signal and the product of said second and third signals, said output signal corresponding to said thrust minus drag over weight ratio, and indicator means responsive to said output signal for displaying an indication of the flight path angle to be attained by said aircraft during unaccelerated flight thereof.
Claim 13
Dependent Claim
122 words
In an airspeed control system for aircraft, apparatus for supplying a signal representative of thrust minus drag over weight ratio comprising accelerometer means for providing first and second signals proportional respectively to the components of acceleration of said aircraft along its longitudinal and normal axes, means providing a third signal proportional to the angle of attack of said aircraft, means for supplying an output signal in accordance with the difference between said first signal and the product of said second and third signals, said output signal corresponding to said thrust minus drag over weight ratio, and indicator means responsive to said output signal for displaying an indication of the flight path angle to be attained by said aircraft during unaccelerated flight thereof.
Claim 14
Dependent Claim
124 words
The apparatus as set forth in claim 11 further including means for providing a control signal in accordance with the difference between a reference airspeed and the actual airspeed of said aircraft, means for supplying a signal in accordance with the acceleration of said craft along its flight path, variable limiting means responsive to said control signal and said flight path acceleration signal, means responsive to the output of said limiting means and adapted for controlling the airspeed of said aircraft, and means responsive to said thrust minus drag over weight output signal for controlling said limiting means in accordance therewith whereby to limit the acceleration of said aircraft to said reference airspeed as a function of said thrust minus drag over weight ratio.
Claim 15
Dependent Claim
141 words
Apparatus by means of which an aircraft having discretely positionable wing surfaces for varying the lift characteristics thereof may be controlled to approach and maintain a desired airspeed consistent with a safe stall margin for each surface position comprising, airspeed responsive means for providing a first signal corresponding to the actual airspeed of said aircraft, manually operable means for selecting a reference airspeed and providing a second signal corresponding thereto and including a limiting means to limit said reference airspeed signal to values consistent with safe stall margins, computer means for providing a third signal corresponding to a minimum safe airspeed above stall for said aircraft lift characteristics, means for controlliNg said limiting means in accordance with the value of said third signal, and utilization means responsive to said first, second, and third signals for controlling the airspeed of said aircraft.
Claim 16
Dependent Claim
141 words
Apparatus by means of which an aircraft having discretely positionable wing surfaces for varying the lift characteristics thereof may be controlled to approach and maintain a desired airspeed consistent with a safe stall margin for each surface position comprising, airspeed responsive means for providing a first signal corresponding to the actual airspeed of said aircraft, manually operable means for selecting a reference airspeed and providing a second signal corresponding thereto and including a limiting means to limit said reference airspeed signal to values consistent with safe stall margins, computer means for providing a third signal corresponding to a minimum safe airspeed above stall for said aircraft lift characteristics, means for controlliNg said limiting means in accordance with the value of said third signal, and utilization means responsive to said first, second, and third signals for controlling the airspeed of said aircraft.
Claim 17
Dependent Claim
40 words
The apparatus as set forth in claim 13 further including asymmetrical limiter means responsive to said second and third signals for limiting the commanded change in airspeed to a lesser extent for increasing commanded airspeeds than for decreasing commanded airspeeds.
Claim 18
Dependent Claim
66 words
The apparatus as set forth in claim 13 further including means responsive to the maximum desired thrust condition of said engines of said aircraft, and means responsive to a predetermined value of the difference between said second and third signals and said first signal for interrupting said control signal to said utilization means for controlling said utilization means in accordance with said engine condition responsive means.
Claim 19
Dependent Claim
54 words
The apparatus as set forth in claim 13 wherein said third signal computer means includes means for supplying a signal corresponding to the actual weight of said aircraft, means for supplying a signal corresponding to said variable lift characteristic, and means for combining said weight and lift characteristic signal for supplying said third signal.
Claim 20
Dependent Claim
78 words
The apparatus as set forth in claim 16, wherein said means for supplying said weight signal comprises, means for supplying a signal corresponding to the actual coefficient of lift of said aircraft, means for supplying a signal corresponding to the lift-over-weight ratio of said aircraft, means for supplying a signal corresponding to the actual airspeed of said craft, and means for deriving said weight signal as a function of said coefficient of lift, airspeed and lift-over-weight ratio signals.
Claim 21
Dependent Claim
166 words
In an airspeed control system for aircraft for providing a signal proportional to the weight of said aircraft comprising, accelerometer means for providing signals respectively proportional to the components of the total acceleration acting on said aircraft along its longitudinal and normal axes, means supplying a signal proportional to the angle of attack of said aircraft, means supplying signals proportional to movement of surfaces which affect the coefficient of lift of said aircraft, means responsive to said angle of attack and surface movement signals for supplying a signal proportional to the actual coefficient of lift of said aircraft, means responsive to both of said acceleration signals, said angle of attack signal and said coefficient of lift signal for providing a signal proportional to the lift-over-weight ratio of said aircraft, means responsive to the airspeed of said aircraft for supplying a signal in accordance therewith, and means for combining said coefficient of lift, airspeed and lift-over-weight ratio signals for providing an output signal proportional to aircraft weight.
Claim 22
Dependent Claim
166 words
In an airspeed control system for aircraft for providing a signal proportional to the weight of said aircraft comprising, accelerometer means for providing signals respectively proportional to the components of the total acceleration acting on said aircraft along its longitudinal and normal axes, means supplying a signal proportional to the angle of attack of said aircraft, means supplying signals proportional to movement of surfaces which affect the coefficient of lift of said aircraft, means responsive to said angle of attack and surface movement signals for supplying a signal proportional to the actual coefficient of lift of said aircraft, means responsive to both of said acceleration signals, said angle of attack signal and said coefficient of lift signal for providing a signal proportional to the lift-over-weight ratio of said aircraft, means responsive to the airspeed of said aircraft for supplying a signal in accordance therewith, and means for combining said coefficient of lift, airspeed and lift-over-weight ratio signals for providing an output signal proportional to aircraft weight.
Claim 23
Dependent Claim
197 words
An angle of attack computer for aircraft comprising first computer means responsive to sources of signals proportional respectively to accelerations of said aircraft along the longitudinal and normal axes of said aircraft, the acceleration of said aircraft along its flight path, and the aircraft flight path angle for providing an initial angle of attack signal including accurate long term components and dynamic error components due to source signal dynamic characteristics under long term and dynamic flight regimes of said aircraft, second computer means responsive to said initial angle of attack signal for providing a signal proportional to the computed weight of said aircraft and having both dynamic and steady state components, the actual weight of said aircraft varying only slowly whereby said dynamic components are inherently due to said dynamics error components, means responsive to said weight signal for providing a weight error signal including essentially only said dynamic components, and means for supplying said weight error signAl in feedback fashion to said first computer means for correcting said dynamic error components of said initial angle of attack signal whereby to provide a final angle of attack signal accurate under both steady state and dynamic flight regimes.
Claim 24
Dependent Claim
197 words
An angle of attack computer for aircraft comprising first computer means responsive to sources of signals proportional respectively to accelerations of said aircraft along the longitudinal and normal axes of said aircraft, the acceleration of said aircraft along its flight path, and the aircraft flight path angle for providing an initial angle of attack signal including accurate long term components and dynamic error components due to source signal dynamic characteristics under long term and dynamic flight regimes of said aircraft, second computer means responsive to said initial angle of attack signal for providing a signal proportional to the computed weight of said aircraft and having both dynamic and steady state components, the actual weight of said aircraft varying only slowly whereby said dynamic components are inherently due to said dynamics error components, means responsive to said weight signal for providing a weight error signal including essentially only said dynamic components, and means for supplying said weight error signAl in feedback fashion to said first computer means for correcting said dynamic error components of said initial angle of attack signal whereby to provide a final angle of attack signal accurate under both steady state and dynamic flight regimes.
Claim 25
Dependent Claim
137 words
The apparatus as set forth in claim 19 wherein said source of the signal proportional to the acceleration of said craft along its flight path includes further computer means comprising means responsive to said longitudinal and normal axes acceleration signals, a signal corresponding to craft airspeed and a signal corresponding to the pitch attitude of said craft for providing an output signal representative of said flight path acceleration and including steady state and short term components, said short term components including dynamics error components due to said accelerometer and pitch attitude signals, wash out filter means for providing a filtered signal including essentially only said short term components, means responsive to said filter signal and said weight error feedback signal for suppressing said dynamic error components and supplying an output signal proportional to said flight path acceleration.
Claim 26
Dependent Claim
75 words
The apparatus as set forth in claim 20 further including means responsive to said longitudinal and normal axes acceleration signals and said final angle of attack signal for supplying a signal proportional to the thrust minus drag over weight of said aircraft, and means responsive to the difference between said thrust minus drag over weight signal and said flight path acceleration signal for providing a signal proportional to the flight path angle of said aircraft.
Claim 27
Dependent Claim
121 words
The apparatus as set forth in claim 19 wherein said sources of the signal proportional to the flight path angle of said aircraft includes further computer means comprising, means responsive to a signal corresponding to the rate of change of altitude of said aircraft, said altitude rate signal including short term error components due to changes in craft pitch attitude, and to a signal corresponding to the Mach number speed of said aircraft for providing a flight path angle signal, lag filter means responsive to said altitude rate signal, and means responsive to said flight path angle signal and said weight error feedback signal for suppressing any dynamics error components of said flight path angle signal introduced by said filter means.
Claim 28
Dependent Claim
119 words
The apparatus as set forth in claim 19 wherein said second computer means comprises, means responsive to said angle of attack signal for supplying a signal corresponding to the coefficient of lift of said aircraft, means responsive to said coefficient of lift signal for supplying a signal corresponding to the ratio of the coefficient of drag to the coefficient of lift, means responsive to said normal axis acceleration signal, said angle of attack signal and said coefficient of drag and coefficient of lift ratio signal for supplying a signal corresponding to the lift over weight ratio of said aircraft, and means responsive to said coefficient of lift and lift over weight ratio signals for supplying said aircraft weight signal.
Claim 29
Dependent Claim
81 words
The apparatus as set forth in claim 19 wherein said means for supplying said weight error signal comprises, filter means responsive to said weight signal for supplying a signal including essentially only the long term components thereof, and means responsive to said weight signal and the output of said filter means for supplying a signal proportional to the difference therebetween, said difference signal corresponding essentially only to the rate of change of said weight signal and constituting said weight error signal.
Claim 30
Dependent Claim
42 words
The apparatus as set forth in claim 24 further including means for limiting the gain of said weight error feedback signal to a predetermined low value whereby to assure accurate response of said weight computer to normal gradual changes in aircraft weight.
Claim 31
Dependent Claim
47 words
The apparatuS as set forth in claim 24 further including means responsive to said weight error feedback signal for controlling the gain thereof, and means for varying the output of the weight signal means in accordance with predetermined known abrupt changes in the weight of said craft.
Claim 32
Dependent Claim
28 words
The apparatus as set forth in claim 24 wherein the normal time constant of said weight signal filter means is on the order of 200 to 500 seconds.
Claim 33
Dependent Claim
63 words
The apparatus as set forth in claim 27 further including lift off detector for changing the time constant of said weight filter means to a small fraction of said normal value during the take-off roll whereby to provide rapid up-dating of said weight signal, and for establishing said normal time constant as the weight of the aircraft is transferred to its lifting surfaces.
Claim 34
Dependent Claim
28 words
The apparatus as set forth in claim 28 wherein said lift off detector means comprises means responsive to a predetermined value of the pitch attitude of said aircraft.
Claim 35
Dependent Claim
189 words
Apparatus for computing the value of an aircraft flight control parameter from sources of primary data which have desirable accuracy characteristics in long term flight regimes but undesirable error characteristics in dynamic flight regimes, the combination comprising, first computer means responsive to said primary data sources for computing an initial value of said parameter including said accurate long term components and said dynamic error components, second computer means responsive to the output of said first computer means for computing the value of a related aircraft parameter which inherently varies only slowly under all flight regimes, whereby any dynamic components in the output of said second computer results from the dynamic error components in the output of said first computer means, means responsive to the output of said second computer means for providing an output including only said dynamic error components, and means for supplying the output of said last mentioned means in feedback fashion to said first computer means for correcting said dynamic error components of said initial value of said parameter whereby to provide a final value of said parameter under both said steady-state and dynamic flight regimes.
Claim 36
Dependent Claim
189 words
Apparatus for computing the value of an aircraft flight control parameter from sources of primary data which have desirable accuracy characteristics in long term flight regimes but undesirable error characteristics in dynamic flight regimes, the combination comprising, first computer means responsive to said primary data sources for computing an initial value of said parameter including said accurate long term components and said dynamic error components, second computer means responsive to the output of said first computer means for computing the value of a related aircraft parameter which inherently varies only slowly under all flight regimes, whereby any dynamic components in the output of said second computer results from the dynamic error components in the output of said first computer means, means responsive to the output of said second computer means for providing an output including only said dynamic error components, and means for supplying the output of said last mentioned means in feedback fashion to said first computer means for correcting said dynamic error components of said initial value of said parameter whereby to provide a final value of said parameter under both said steady-state and dynamic flight regimes.
Claim 37
Dependent Claim
205 words
Apparatus for computing the airborne weight of an aircraft at lift off thereof from a runway comprising, means for supplying a signal corresponding to a predetermined coefficient of lift at a predetermined lift off pitch attitude, means for supplying a signal corresponding to the airborne coefficient of lift of said aircraft, means for supplying signals corresponding to the airborne lift over weight ratio of said aircraft, and, to the speed of said aircraft, weight computer means selectively responsive to said airborne coefficient of lift signal and said predetermined coefficient of lift signal and to said lift over weight ratio and airspeed signals, and including filter means having selectable long term and short term time constants for supplying an output signal corresponding to the lift off weight of said aircraft, lift off detector means responsive to said predetermined lift off pitch attitude of said aircraft for rendering said weight computer means responsive to said predetermined coefficient of lift signal and said short term filter time constant during the take off ground roll and to said airborne coefficient of lift signal and said long filter time constant at lift off, and feedback means responsive to said computed weight signal for correcting said airborne coefficient of lift signal.
Claim 38
Dependent Claim
205 words
Apparatus for computing the airborne weight of an aircraft at lift off thereof from a runway comprising, means for supplying a signal corresponding to a predetermined coefficient of lift at a predetermined lift off pitch attitude, means for supplying a signal corresponding to the airborne coefficient of lift of said aircraft, means for supplying signals corresponding to the airborne lift over weight ratio of said aircraft, and, to the speed of said aircraft, weight computer means selectively responsive to said airborne coefficient of lift signal and said predetermined coefficient of lift signal and to said lift over weight ratio and airspeed signals, and including filter means having selectable long term and short term time constants for supplying an output signal corresponding to the lift off weight of said aircraft, lift off detector means responsive to said predetermined lift off pitch attitude of said aircraft for rendering said weight computer means responsive to said predetermined coefficient of lift signal and said short term filter time constant during the take off ground roll and to said airborne coefficient of lift signal and said long filter time constant at lift off, and feedback means responsive to said computed weight signal for correcting said airborne coefficient of lift signal.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-09-12 | 1976-03-13 | 1976-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-12 | 1980-03-13 | 1980-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-12 | 1984-03-13 | 1984-09-12 | $7700.00 | Window Closed / Lapsed |