US2728537A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Aircraft with shrouded propelling and lifting rotors
Assignee: Individual
•
Filing: 1953-01-06
•
Granted: 1955-12-27
•
Expires: 1973-01-06
Abstract
No abstract record available.
Inventors
- 👤 Arthur B Elkins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:31
CPC Classifications
B; B64; B64C; B64C29/00; B64C29/0008; B64C29/0016; B64C29/0025
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) | 1958-12-26 | 1959-06-27 | 1959-12-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-12-26 | 1963-06-27 | 1963-12-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-12-26 | 1967-06-27 | 1967-12-27 | $7700.00 | Window Closed / Lapsed |