US2689011A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Helicopter rotor construction
Assignee: McDonnell Aircraft Corp
•
Filing: 1948-02-09
•
Granted: 1954-09-14
•
Expires: 1968-02-09
Abstract
No abstract record available.
Inventors
- 👤 Constantine L Zakhartchenko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 09:40
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/04; B64C27/12; B64C27/16; B64C27/18
Claims Analysis
Total Claims: 0
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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) | 1957-09-13 | 1958-03-15 | 1958-09-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-09-13 | 1962-03-15 | 1962-09-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-09-13 | 1966-03-15 | 1966-09-14 | $7700.00 | Window Closed / Lapsed |