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US2680579A
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Rotor speed control for rotorfixed wing aircraft
Assignee: McDonnell Aircraft Corp
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Filing: 1951-03-26
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Granted: 1954-06-08
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Expires: 1971-03-26
Abstract
No abstract record available.
Inventors
- 👤 Kurt H Hohenemser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 06:37
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/04; B64C27/12
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2421364A
Cited
US2425651A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-06-07 | 1957-12-07 | 1958-06-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-06-07 | 1961-12-07 | 1962-06-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-06-07 | 1965-12-07 | 1966-06-08 | $7700.00 | Window Closed / Lapsed |