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Patent US2721044A successfully refreshed from Google Patents.
US2721044A
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Cargo helicopter assembly
Assignee: Individual
•
Filing: 1952-12-18
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Granted: 1955-10-18
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Expires: 1972-12-18
Abstract
No abstract record available.
Inventors
- 👤 Raymond A Young
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 09:18
CPC Classifications
B; B64; B64C; B64C37/00; B64C37/02; B64D; B64D1/00; B64D1/22; B66; B66C; B66C1/00; B66C1/10; B66F; B66F19/00; B64C27/00; B64C27/04
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1340053A
Cited
US1546443A
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US1705904A
Cited
US2413074A
Cited
US2540543A
Cited
US2529629A
Cited
US2589826A
Cited
US2613961A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1958-10-17 | 1959-04-18 | 1959-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-10-17 | 1963-04-18 | 1963-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-10-17 | 1967-04-18 | 1967-10-18 | $7700.00 | Window Closed / Lapsed |