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US2521393A
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US
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Aircraft heating system
Assignee: Lockheed Martin Corp
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Filing: 1946-08-13
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Granted: 1950-09-05
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Expires: 1966-08-13
Abstract
No abstract record available.
Inventors
- 👤 Bernard L Messinger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:31
CPC Classifications
B; B64; B64D; B64D13/00; B64D13/06; B64D13/08; Y; Y02; Y02T; Y02T50/00; Y02T50/50
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-09-04 | 1954-03-06 | 1954-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-09-04 | 1958-03-06 | 1958-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-09-04 | 1962-03-06 | 1962-09-05 | $7700.00 | Window Closed / Lapsed |