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US3516375A
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Horizon indicators for assisting helicopier landings on ships
Assignee: Department of National Defence
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Filing: 1968-10-21
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Granted: 1970-06-23
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Expires: 1988-10-21
Abstract
No abstract record available.
Inventors
- 👤 Peter Charlton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 15:18
CPC Classifications
G; G01; G01C; G01C19/00; G01C19/02; G01C19/04; G01C19/32; B; B64; B64F; B64F1/00; B64F1/18
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1558567A
Cited
US2368159A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-06-22 | 1973-12-22 | 1974-06-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-06-22 | 1977-12-22 | 1978-06-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-06-22 | 1981-12-22 | 1982-06-23 | $7700.00 | Window Closed / Lapsed |