US3896432A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Perspective radar airport recognition and landing guidance system
Assignee: BAE Systems Aircraft Controls Inc
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Filing: 1973-08-03
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Granted: 1975-07-22
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Expires: 1993-08-03
Abstract
Abstract A self-contained perspective radar system is modified and improved by providing an additional display on the radar screen in accordance with known information such as the range and bearing of the aircraft at a given fix point during an approach and landing operation. The additional display may take the form of a vertical vector generated on the display screen the upper terminal point of which indicates the location of the threshold of the airport runway and the overall length of which decreases with decreasing range as the aircraft approaches the runway. The horizontal position of this vector will also indicate any deviation in heading. In a more advanced embodiment, the additional display may actually constitute a generated runway outline for comparison with the actual runway detected by the perspective radar. In it''s most sophisticated form, in addition to other features, an actual image containing all known information of the physical characteristics of an airport complex is stored rather than displayed in a condition such that it may be compared with the perspective radar display by a suitable comparing means which provides output signals such as error signals to advise the pilot of a mismatching of the actual perspective radar picture with the stored image. The same output signals may be used to automatically control an auto-pilot so that approach and landing of the aircraft can be effected completely automatically without the necessity of any pilot intervention and by a system which is wholly self-contained within the aircraft.
Inventors
- 👤 David W Young
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 11:06
CPC Classifications
G; G01; G01C; G01C23/00; G01C23/005; G01S; G01S13/00; G01S13/74; G01S13/75; G01S13/88; G01S13/91; G01S13/913; G01S7/00; G01S7/02; G01S7/04; G01S7/06; G01S7/10; G01S7/20; H; H01; H01Q; H01Q15/00; H01Q15/0006; H01Q15/0013
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
121 words
An airport recognition and landing guidance system for use in an aircraft as a completely self-contained system within the aircraft operative independently of any landing signals emanating from the airport or other ground areas after a standard FAA Air Traffic Control final fix is established, comprising, in combination: a. a radar system including a PRF synchronizing trigger signal generator and antenna means, said radar system generating vertical, horizontal, and video radar signals for providing a basic perspective display of actual, not stylized terrain in front of the aircraft when viewed on a display screen; and b. guidance control means incorporating known information relative to an airport complex for comparison with the perspective radar information in said radar signals of actual terrain.
Claim 2
Dependent Claim
121 words
An airport recognition and landing guidance system for use in an aircraft as a completely self-contained system within the aircraft operative independently of any landing signals emanating from the airport or other ground areas after a standard FAA Air Traffic Control final fix is established, comprising, in combination: a. a radar system including a PRF synchronizing trigger signal generator and antenna means, said radar system generating vertical, horizontal, and video radar signals for providing a basic perspective display of actual, not stylized terrain in front of the aircraft when viewed on a display screen; and b. guidance control means incorporating known information relative to an airport complex for comparison with the perspective radar information in said radar signals of actual terrain.
Claim 3
Dependent Claim
152 words
A system according to claim 1, including a cathode ray display screen having vertical, horizontal and video inputs connected to receive said radar signals respectively to provide a perspective display of the actual terrain, and in which said guidance control means includes: a. first means receiving trigger signals from said trigger signal generator and providing first output signals to said video input of said display in addition to video signals from said antenna means; b. second means providing horizontal position second output signals to said video input of said display; and c. control means connected to said first and second means to control the points in time in which the signals are applied to said video input in accordance with said known information whereby an additional display is generated on said display screen by said first and second signals enabling the pilot to quickly locate the airport complex on the display screen.
Claim 4
Dependent Claim
99 words
A system according to claim 2, including means defining horizontal lines vertically spaced on the display screen indicating in degrees the depression angle to the perspective display of actual terrain generated by the radar signals which become glide slopes that can be followed by the aircraft if the terrain contains an airport and an approach for landing is attempted; and means defining a single vertical line bisecting the screen and defining a zero degree bearing, there being provided a scale in degrees horizontally extending to the right and left of said vertical line below said screen indicating bearing deviations.
Claim 5
Dependent Claim
235 words
A system according to claim 2, in which said known information includes the range and heading of the aircraft to the airport complex from a given fix point of the aircraft, said screen including a bearing scale, and in which said first means and control means include delay means receiving a trigger signal from said trigger signal generator and providing said first output signals to said video input of said display; and means responsive to the estimated range to the airport complex and the estimated ground speed of the aircraft at said given fix point connected to said delay means to vary the points in time that said first output signals are applied to said video input; and said second means and said control means including means responsive to the magnetic heading of said aircraft at said given fix point connected to the horizontal input and including gate means connected to the video input such that said additional display comprises a vertical vector on said display screen the length of which decreases with decreasing range to said airport complex and the horizontal position of which is determined by said magnetic heading, whereby the pilot may quickly locate the airport complex on the radar screen by observing the end point of said vertical vector and may also be advised of any heading deviation by observing the horizontal position of said vector relative to said bearing scale.
Claim 6
Dependent Claim
159 words
A system according to claim 1, including a cathode ray display screen having vertical, horizontal and video inputs connected to receive said radar signals respectively to provide a perspecTive display of the actual terrain, and in which said guidance control means includes first and second delay pulse generators responsive to trigger signals from said trigger signal generator to provide two pulses in response to each trigger pulse delayed in time to said video input, thereby generating a pair of spaced parallel horizontal lines on said radar display screen for comparison with the perspective display, the time interval between the pulses representing a given distance in elevation as determined from said known information whereby the pilot may determine if his approach along a glide slope intercepting the airport runway threshold is within the elevation distance defined by the pair of horizontal lines, the pilot knowing that if the glide slope is straddled by the lines, the approach progress is correct.
Claim 7
Dependent Claim
169 words
A system according to claim 2, in which said first and second means and control means comprise a runway outline generating means, the runway outline defining said additional display, said generating means including a pulse generator providing two pulses defining said first signals, said pulses being seperated in time to indicate a perspective distance on said display corresponding to the known length of the airport runway, the vertical position of the pulses being determined initially by the known range of the airport runway; and means responsive to the azimuth angles of the corners of the threshold and termination lines of the runway providing the second signals to the video input of the display screen to generate on the display screen a perspective outline of the runway as it would appear at said given fix point for comparison with the perspective radar display actually detected, whereby the pilot is aided in recognizing the airport runway by comparing the generated runway outline and the actual perspective radar display of the runway.
Claim 8
Dependent Claim
86 words
A system according to claim 1, in which said guidance control means includes image storing means defining physical characteristics of said airport complex; a comparator circuit; means connecting said image storing means to one side of said comparator and perspective radar signals to the other side of said comparator; and means connected to said comparator for generating control output signals indicative of a proper matching between at least one characteristic of the stored airport complex image information and the actual information detected by said perspective radar.
Claim 9
Dependent Claim
35 words
A system according to claim 7, in which said output signals are connected to an auto-pilot for automatic landing control of said aircraft by proper matching of said stored image with the perspective radar signals.
Claim 10
Dependent Claim
38 words
A system according to claim 8, including background attenuating means connected into said perspective radar system for modifying the perspective radar signals to enhance the pertinent features corresponding to the pertinent features in said airport complex image information.
Claim 11
Dependent Claim
37 words
A system according to claim 7, in which said one characteristic of the stored airport complex image comprises a rotating beacon light having light emitting surfaces highly reflective of the radar radiation emitted by said antenna 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) | 1978-07-21 | 1979-01-20 | 1979-07-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-21 | 1983-01-20 | 1983-07-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-21 | 1987-01-20 | 1987-07-22 | $7700.00 | Window Closed / Lapsed |