US2491549A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Helicopter
Assignee: RTX Corp
•
Filing: 1945-01-24
•
Granted: 1949-12-20
•
Expires: 1965-01-24
Abstract
No abstract record available.
Inventors
- 👤 James H Brewster
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:11
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/82; B64C2027/8227
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
GB189710620A
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US848055A
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US1344297A
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US1635897A
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US1779524A
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US1890931A
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US2130918A
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US2277378A
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US2225002A
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US2369652A
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US2378617A
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US2385889A
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US2415622A
Cited
US2394513A
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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) | 1952-12-19 | 1953-06-20 | 1953-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-12-19 | 1957-06-20 | 1957-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-12-19 | 1961-06-20 | 1961-12-20 | $7700.00 | Window Closed / Lapsed |