Helicopter rotors and the like
Abstract
Abstract AIR IS DISCHARGED FROM TWO ADJACENT SLOTS EXTENDING ALONG THE SPAN OF A HELICOPTER ROTOR BLADE. THE AIR IS CONTROLLED CYCLICALLY BY THROTTLE VALVES DISPOSED CIRCUMFERENTIALLY ABOUT THE ROTOR AXIS SO THAT LIFT ON THE BLADE MAY BE VARIED IN ACCORDANCE WITH ITS ROTATION, NO INCIDENCE CHANGE BEING INVOLVED. UNDER CERTAIN FLIGHT CONDITIONS WHEN THE AIR DEMAND IS SMALL (E.G. IN HOVERING FLIGHT), THE AIR FLOW TO ONE OF THE SLOTS IS BLANKED OFF, THE THROTTLE VALVES BEING SUITABLY PROFILED TO EFFECT THIS WHILE STILL REGULATING FLOW TO THE OTHER SLOT. PREFERABLY THE SLOTS ARE OF DIFFERING WIDTHS AND THE WIDER ONE IS THAT WHICH IS BLANKED OFF. THREE OR MORE SLOTS MAY BE USED IF DESIRED BY SUITABLE ARRANGEMENTS OF AIR PASSAGES AND VALVE PROFILES.
Inventors
- 👤 Austin Richard Seed
Bibliographic Details
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