US3838425A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Design for reducing radar cross section of engine inlets
Assignee: United States Department of the Navy
•
Filing: 1973-03-28
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Granted: 1974-09-24
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Expires: 1993-03-28
Abstract
Abstract A radar-absorbing shield for aircraft engines of the type having inlet cavities comprising a geometrically shaped piece of radarabsorbing material which is movably attached to the fuselage of the aircraft near the engine inlet. The shield can be moved under and in front of the inlet to shield the cavity from waves from surface radar, or it can be moved so that it is flush with the fuselage when high maneuverability is required. A shield may be placed near each engine on the aircraft.
Inventors
- 👤 K Ishimitsu
- 👤 J Kelly
- 👤 D Miller
- 👤 G Taylor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 12:31
CPC Classifications
B; B64; B64D; B64D33/00; B64D33/02; B64D2033/0253; B64D2033/026
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
80 words
A device for reducing the radar cross section of an aircraft engine inlet cavity comprising: a shield movably attached to the fuselage of an aircraft, said sheild being extendable from the fuselage so that it extends forward from the inlet cavity and below the cavity in the path of waves coming from a surface-positioned radar, said shield also being retractable to a position which is flush with the fuselage, said shield acting to prevent radar waves from entering said cavity.
Claim 2
Independent Claim
80 words
A device for reducing the radar cross section of an aircraft engine inlet cavity comprising: a shield movably attached to the fuselage of an aircraft, said sheild being extendable from the fuselage so that it extends forward from the inlet cavity and below the cavity in the path of waves coming from a surface-positioned radar, said shield also being retractable to a position which is flush with the fuselage, said shield acting to prevent radar waves from entering said cavity.
Claim 3
Dependent Claim
12 words
A device as in claim 1, wherein said shield is triangularly shaped.
Claim 4
Dependent Claim
15 words
A device as in claim 1, wherein said shield is formed from a radar-absorbing material.
Claim 5
Dependent Claim
20 words
A device as in claim 1, wherein said shield is made of a rigid material coated with a radar-absorbing material.
References Cited (Backward Citations)
US3168999A
Cited
US3283324A
Cited
US3474988A
Cited
US3487410A
Cited
US3509568A
Cited
US3652036A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-09-23 | 1978-03-25 | 1978-09-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-23 | 1982-03-25 | 1982-09-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-23 | 1986-03-25 | 1986-09-24 | $7700.00 | Window Closed / Lapsed |