US4726547A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Helicopter with high forward speed
Assignee: Dornier GmbH
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Filing: 1986-11-05
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Granted: 1988-02-23
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Expires: 2006-11-05
Abstract
Abstract A helicopter having the usual tiltable, vertical thrust and lift producing rotor, a separate forward thrust producing propeller as well as provisions for yaw control and compensation is improved in that the propeller is constructed as unshrouded propulsion device. A pair of flow deflecting rudders is arranged downstream from the propeller and symmetrically to both sides of the craft; a frame on the tail portion of the craft includes vertical shafts for pivotally mounting the rudders. A T shaped support structure in the frame includes regular elevational, horizontally extending stabilizer fins and carrier arms. An elevator is arranged upstream from the propeller and from one of the elevational stabilizer fins. The elevator reaches laterally beyond and longitudinally alongside the one fin or beyond a circle provided by the propeller.
Inventors
- 👤 Herbert Zimmer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 03:43
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/32; B64C27/325; B64C27/82; B64C2027/8236; B64C2027/8263; B64C2027/8272
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
106 words
In a helicopter type craft having a tiltable, vertical thrust and lift producing rotor, a separate forward thrust producing propeller as well as means for yaw control and compensation, the improvement comprising: said propeller being constructed as unshrouded propulsion device; a pair of flow deflecting rudders arranged downstream from said propeller and symmetrically to both sides of a vertical plane through a longitudinal axis of the craft; and a frame on the tail portion of the craft and including vertical shafts for pivotally mounting said rudders, said frame including support structure for regular elevational, horizontally extending stabilizer fins and an elevator arranged upstream from said propeller.
Claim 2
Dependent Claim
106 words
In a helicopter type craft having a tiltable, vertical thrust and lift producing rotor, a separate forward thrust producing propeller as well as means for yaw control and compensation, the improvement comprising: said propeller being constructed as unshrouded propulsion device; a pair of flow deflecting rudders arranged downstream from said propeller and symmetrically to both sides of a vertical plane through a longitudinal axis of the craft; and a frame on the tail portion of the craft and including vertical shafts for pivotally mounting said rudders, said frame including support structure for regular elevational, horizontally extending stabilizer fins and an elevator arranged upstream from said propeller.
Claim 3
Dependent Claim
25 words
The improvement as in claim 1, said support structure including vertically rearwardly extending stabilizer fins and carrier arms extending rearwardly from said horizontal stabilizer fine.
Claim 4
Dependent Claim
39 words
The improvement as in claim 2, there being a T shaped support structure of which the vertically oriented stabilizer fins constitute the stem, and horizontally extending vertical elevational stabilizer constitute cross bars, the arms extending from said elevational stabilizers.
Claim 5
Dependent Claim
46 words
The improvement as in claim 3 wherein said vertically positioned stabilizer fins as well as said horizontal elevational stabilizer fins are positioned in the rear towards the tail end of the craft so as to be outside of the down draft produced by the helicopter rotor.
Claim 6
Dependent Claim
21 words
The improvement as in claim 3 wherein an elevator is connected, as balanced elevator to one of said elevational stabilizer fins.
Claim 7
Dependent Claim
30 words
The improvement as in claim 5 wherein, as seen along the longitudinal axis of the craft, said balanced elevator extends laterally beyond a circle provided by said tail end propeller.
Claim 8
Dependent Claim
33 words
The improvement as in claim 1 wherein said flow deflecting rudders are provided with closing flaps which open automatically in case of a large angle of attack and deflection of the respective rudder.
Claim 9
Dependent Claim
18 words
The improvement as in claim 1 said elevator being disposed upstream from one of the elevational stabilizer fins.
Claim 10
Dependent Claim
17 words
The improvement as in claim 8, said elevator reaching laterally beyond and longitudinally alongside the one fin.
Claim 11
Dependent Claim
17 words
The improvement as in claim 8, said elevator extending laterally beyond a circle provided by said propeller.
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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) | 1991-02-22 | 1991-08-24 | 1992-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-02-22 | 1995-08-24 | 1996-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-02-22 | 1999-08-24 | 2000-02-23 | $7700.00 | Window Closed / Lapsed |