US3821698A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Altitude alerting system
Assignee: Lear Avia Corp
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Filing: 1972-07-13
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Granted: 1974-06-28
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Expires: 1992-07-13
Abstract
Abstract An alerter for use in aircraft to provide the pilot with visual and aural signaling of his altitude course with respect to a preselected flight altitude. A transducer senses the aircraft''s altitude and generates corresponding electrical signals that are compared with that of the selected altitude. A computer-control unit derives alerting signals that selectively energize a ''''high'''' or a ''''low'''' pilot light to indicate when the pilot is above or below the desired altitude. A preset ''''inner'''' distance therefrom, as 500 feet in either direction, defines a clearance window that denotes on-altitude. Also, a horn is sounded when the plane departs from such inner window, as well as when it approaches within a preset ''''outer'''' range from the set altitude, as 1,000 feet. The pilot is thereby alerted by simple yet effective indications to guide him in acquiring or maintaining his desired altitude.
Inventors
- 👤 E Tippetts
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 07:27
CPC Classifications
G; G01; G01C; G01C5/00; G01C5/005
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
220 words
An altitude alerting system for an aircraft comprising an altitude transducer with a first adjustable resistance providing a first electrical signal of magnitude proportional to the ambient altitude of the aircraft, an indicator of desired aircraft altitude Ho including manual means for selecting the altitude Ho therein, a second adjustable resistance coupled with said manual means providing a second electrical signal of magnitude proportional to altitude Ho selected, a ''''low'''' member actuated into visual display when the aircraft is below the selected altitude Ho by more than a first preset distance, a ''''high'''' member that is actuated into visual display when the aircraft is above altitude Ho by more than a second preset distance, a summing amplifier responsive to both of said electrical signals to provide a net control signal that corresponds to their magnitude difference, and electrical control means including a series of prebiased signal comparators responsive to said control signal to derive ''''low'''' range output signals when the aircraft is below the first preset (11 con.) distance from the Ho level and ''''high'''' range output signals when it is above the second preset distance therefrom, said members being in circuit with said control means whereby the ''''low'''' member is actuated into display during below-Ho flight range and the ''''high'''' member is actuated into display during above-Ho flight range.
Claim 2
Dependent Claim
220 words
An altitude alerting system for an aircraft comprising an altitude transducer with a first adjustable resistance providing a first electrical signal of magnitude proportional to the ambient altitude of the aircraft, an indicator of desired aircraft altitude Ho including manual means for selecting the altitude Ho therein, a second adjustable resistance coupled with said manual means providing a second electrical signal of magnitude proportional to altitude Ho selected, a ''''low'''' member actuated into visual display when the aircraft is below the selected altitude Ho by more than a first preset distance, a ''''high'''' member that is actuated into visual display when the aircraft is above altitude Ho by more than a second preset distance, a summing amplifier responsive to both of said electrical signals to provide a net control signal that corresponds to their magnitude difference, and electrical control means including a series of prebiased signal comparators responsive to said control signal to derive ''''low'''' range output signals when the aircraft is below the first preset (11 con.) distance from the Ho level and ''''high'''' range output signals when it is above the second preset distance therefrom, said members being in circuit with said control means whereby the ''''low'''' member is actuated into display during below-Ho flight range and the ''''high'''' member is actuated into display during above-Ho flight range.
Claim 3
Dependent Claim
47 words
An altitude alerting system as claimed in claim 1, in which first and second of said comparators are selectively responsive to the control signal of said amplifier whereby the ''''low'''' and ''''high'''' range output signals are derived in correspondence with the relative magnitude of the control signal.
Claim 4
Dependent Claim
46 words
An altitude alerting system as claimed in claim 2, further including biasing means connected with the inputs of said first and second comparators to selecTively determine control signal levels to trigger the respective comparators and establish regions above selected Ho level of non-display by said members.
Claim 5
Dependent Claim
43 words
An altitude alerting system as claimed in claim 1, further including an aural indicator in circuit connection with the comparators, and circuit means for energizing said aural indicator for a predetermined interval in response initiation of the ''''low'''' and ''''high'''' range output signals.
Claim 6
Dependent Claim
43 words
An altitude alerting system as claimed in claim 3, further including an aural indicator in circuit connection with the comparators, and circuit means for energizing said aural indicator for a predetermined interval in response initiation of the ''''low'''' and ''''high'''' range output signals.
Claim 7
Dependent Claim
55 words
An altitude alerting system as claimed in claim 5, further including third and fourth comparators responsive to said control signal and selectively biased to provide respective output signals that correspond to preset outer levels above and below preset level Ho whereby said aural indicator is actuated when the aircraft approaches into said respective outer levels.
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) | 1977-06-27 | 1977-12-27 | 1978-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-27 | 1981-12-27 | 1982-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-27 | 1985-12-27 | 1986-06-28 | $7700.00 | Window Closed / Lapsed |