US5036469A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pitch attitude command flight control system for landing flare
Assignee: Boeing Co
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Filing: 1989-03-02
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Granted: 1991-07-30
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Expires: 2009-03-02
Abstract
Abstract This invention provides a flare control modification for pilot-in-the-loop aircraft maneuver command electronic flight control systems. During flare, pilot pitch control inputs are interpreted as incremental pitch attitude commands. The flare control modification allows conventional piloting technique (i.e., pitch controller pull-and-hold) to be used during flare, while retaining the benefits of maneuver command system masking effects of gusts, winds, wind shear, and variations in airplane weight, balance, and aerodynamic configuration.
Inventors
- 👤 Scott L. Pelton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 15:02
CPC Classifications
G; G05; G05D; G05D1/00; G05D1/04; G05D1/06; G05D1/0607; G05D1/0653; G05D1/0676
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
109 words
In an aircraft maneuver command electronic flight control system wherein during up-and-away flight a continuing pitch axis control signal is produced by a continuing steady input applied to a pilot-operated pitch axis control device, the improvement comprising a flare mode modification that becomes active during the flare portion of a landing, said flare mode modification including command modification means responsively connected to said pilot-operated pitch axis control device for receiving said pitch axis control signal and producing an incremental pitch axis command relative to the pitch attitude of the aircraft at the start of flare based on the continuing steady input applied to said pilot-operated pitch axis control device.
Claim 2
Dependent Claim
109 words
In an aircraft maneuver command electronic flight control system wherein during up-and-away flight a continuing pitch axis control signal is produced by a continuing steady input applied to a pilot-operated pitch axis control device, the improvement comprising a flare mode modification that becomes active during the flare portion of a landing, said flare mode modification including command modification means responsively connected to said pilot-operated pitch axis control device for receiving said pitch axis control signal and producing an incremental pitch axis command relative to the pitch attitude of the aircraft at the start of flare based on the continuing steady input applied to said pilot-operated pitch axis control device.
Claim 3
Dependent Claim
49 words
The improvement claimed in claim 1, wherein: (a) said maneuver command electronic flight control system includes an integrator that integrates said pitch axis control signal; (b) said command modification means includes integration cancellation means for cancelling the effect of integrating said pitch axis control signal by bypassing said integrator.
Claim 4
Dependent Claim
55 words
The improvement claimed in claim 1, wherein: (a) said maneuver command electronic flight control system includes an integrator that integrates said pitch axis control signal; and, (b) said command modification means includes integration cancellation means comprising a differentiator connected in series with said integrator for cancelling the effect of integrating said pitch axis control signal.
Claim 5
Dependent Claim
15 words
The improvement claimed in claim 3, wherein, signalwise, said differentiator is upstream of said integrator.
Claim 6
Dependent Claim
24 words
The improvement claimed in claim 4, wherein said integrator is set to a predetermined value when the flare portion of a landing maneuver begins.
Claim 7
Dependent Claim
37 words
The improvement claimed in claims 3, 4, or 5, wherein said differentiator is formed by changing a type zero (0) filter to a type negative one (-1) filter when the flare portion of a landing maneuver begins.
Claim 8
Dependent Claim
14 words
The improvement claimed in claim 6, wherein said filter is a first order filter.
Claim 9
Dependent Claim
17 words
The improvement claimed in claim 6, wherein said type zero (0) filter has a simple unity gain.
Claim 10
Independent Claim
139 words
A method of controlling, during the flare portion of a landing maneuver, the pitch axis movement of an aircraft controlled by an aircraft maneuver command electronic flight control system, said method comprising the steps of: determining the height of the aircraft above the ground during said landing maneuver; and controlling the value of an incremental pitch axis command relative to a reference value in response to the deflection of a pilot-operated pitch axis control device when the aircraft descends below a predetermined altitude above the ground during said landing maneuver, said reference value determined by the pitch attitude of the aircraft when the aircraft descends below said predetermined altitude above the ground during said landing maneuver, said incremental pitch axis command controlling the pitch axis movement of the aircraft controlled by said aircraft maneuver command electronic flight control system.
Claim 11
Independent Claim
139 words
A method of controlling, during the flare portion of a landing maneuver, the pitch axis movement of an aircraft controlled by an aircraft maneuver command electronic flight control system, said method comprising the steps of: determining the height of the aircraft above the ground during said landing maneuver; and controlling the value of an incremental pitch axis command relative to a reference value in response to the deflection of a pilot-operated pitch axis control device when the aircraft descends below a predetermined altitude above the ground during said landing maneuver, said reference value determined by the pitch attitude of the aircraft when the aircraft descends below said predetermined altitude above the ground during said landing maneuver, said incremental pitch axis command controlling the pitch axis movement of the aircraft controlled by said aircraft maneuver command electronic flight control system.
Claim 12
Dependent Claim
77 words
The method claimed in claim 9, wherein pitch axis movement of said aircraft during up-and-away flight is controlled by integrating pitch axis commands that are representative of the deflection of said pilot-operated pitch axis control device and wherein said step of controlling the value of an incremental pitch axis command relative to a reference value is created by not integrating said pitch axis commands that are representative of the deflection of said pilot-operated pitch axis control device.
Claim 13
Dependent Claim
74 words
The method claimed in claim 9, wherein pitch axis movement of said aircraft during up-and-away flight is controlled by integrating pitch axis commands that are representative of the deflection of said pilot-operated control device and wherein said step of controlling the value of an incremental pitch axis command relative to a reference value is created by differentiating said pitch axis commands that are representative of the deflection of said pilot-operated pitch axis control device.
Claim 14
Dependent Claim
34 words
The method claimed in claim 11, wherein said pitch axis commands that are representative of the deflection of said pilot-operated pitch axis control device are differentiated prior to said pitch axis commands being integrated.
Claim 15
Dependent Claim
30 words
The method claimed in claim 12, wherein said pitch axis commands that are representative of the deflection of said pilot-operated pitch axis control device are filtered as well as differentiated.
Claim 16
Dependent Claim
29 words
The method claimed in claim 13, wherein said pitch axis commands that are representative of the deflection of said pilot-operated control device are filtered by a first order filter.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-07-29 | 1995-01-28 | 1995-07-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-07-29 | 1999-01-28 | 1999-07-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-07-29 | 2003-01-28 | 2003-07-30 | $7700.00 | Window Closed / Lapsed |