US4563684A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of predicting the approaching stall of an aircraft wing
Assignee: Marinvent Corp
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Filing: 1983-10-03
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Granted: 1986-01-07
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Expires: 2003-10-03
Abstract
Abstract The approaching stall of an aircraft wing is predicted using an inherent characteristic of the airflow as the stall is approached. The airspeed over the wing is sensed at a predetermined location spaced above the top surface of the wing, input signals are produced representative of airspeed fluctuations caused by air turbulence, input signals are used to produce a signal representative of the ratio of the airspeed fluctuations to the average airspeed, and the ratio signal produces a signal indicating imminent stalling.
Inventors
- 👤 John M. Maris
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 04:52
CPC Classifications
B; B64; B64D; B64D43/00; B64D43/02
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
96 words
Apparatus for predicting the approaching stall of an aircraft wing, comprising: means for sensing airspeed over the wing at a predetermined location spaced above the top surface of the wing and for thereby producing input signals representative of airspeed fluctuations at said location, said fluctuations being caused by air turbulence over the wing; means for using said input signals to produce a signal representative of the ratio of the airspeed fluctuations at said location to the average airspeed at said location; and means for using said ratio signal to produce a signal indicative of imminent stalling.
Claim 2
Dependent Claim
96 words
Apparatus for predicting the approaching stall of an aircraft wing, comprising: means for sensing airspeed over the wing at a predetermined location spaced above the top surface of the wing and for thereby producing input signals representative of airspeed fluctuations at said location, said fluctuations being caused by air turbulence over the wing; means for using said input signals to produce a signal representative of the ratio of the airspeed fluctuations at said location to the average airspeed at said location; and means for using said ratio signal to produce a signal indicative of imminent stalling.
Claim 3
Dependent Claim
111 words
Apparatus for predicting the approaching stall of an aircraft wing, comprising: means directly exposed to the free airstream over the wing for sensing the speed of the free airstream at a predetermined location spaced above the top surface of the wing and above the boundary layer, to thereby produce input signals representative of airspeed fluctuations at said location, said fluctuations being caused by air turbulence over the wing; means for using said input signals to produce a signal representative of the ratio of the airspeed fluctuations at said location to the average airspeed at said location, and means for using said ratio signal to produce a signal indicative of imminent stalling.
Claim 4
Dependent Claim
111 words
Apparatus for predicting the approaching stall of an aircraft wing, comprising: means directly exposed to the free airstream over the wing for sensing the speed of the free airstream at a predetermined location spaced above the top surface of the wing and above the boundary layer, to thereby produce input signals representative of airspeed fluctuations at said location, said fluctuations being caused by air turbulence over the wing; means for using said input signals to produce a signal representative of the ratio of the airspeed fluctuations at said location to the average airspeed at said location, and means for using said ratio signal to produce a signal indicative of imminent stalling.
Claim 5
Dependent Claim
17 words
The apparatus of claim 1 or 2, wherein said sensing means comprises a heated body probe means.
Claim 6
Dependent Claim
39 words
The apparatus of claim 1 or 2, wherein said means for using said input signals is for continuously producing a signal representative of the ratio of the airspeed fluctuations at said location to the average airspeed at said location.
Claim 7
Dependent Claim
52 words
The apparatus of claim 1 or 2, wherein said means for using said input signals is for producing a signal indicative of imminent stalling when the air turbulence exceeds an airspeed dependent threshold, and wherein rate-term means are included to initiate an earlier warning signal if said turbulence threshold is rapidly approached.
Claim 8
Dependent Claim
42 words
The apparatus of claim 1 or 2, wherein there is a plurality of said sensing means, for mounting at a plurality of said locations, spaced spanwise along said wing, there being a single said using means responsive to all said sensing means.
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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) | 1989-01-06 | 1989-07-08 | 1990-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-01-06 | 1993-07-08 | 1994-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-01-06 | 1997-07-08 | 1998-01-07 | $7700.00 | Window Closed / Lapsed |