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US2653314A
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Air traffic control system
Assignee: Unisys Corp
•
Filing: 1949-12-21
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Granted: 1953-09-22
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Expires: 1969-12-21
Abstract
No abstract record available.
Inventors
- 👤 George B Litchford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:00
CPC Classifications
G; G01; G01S; G01S1/00; G01S1/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2252083A
Cited
US2480123A
Cited
US2505314A
Cited
US2535107A
Cited
US2538065A
Cited
US2534843A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-09-21 | 1957-03-23 | 1957-09-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-09-21 | 1961-03-23 | 1961-09-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-09-21 | 1965-03-23 | 1965-09-22 | $7700.00 | Window Closed / Lapsed |