Showing papers on "Wing root published in 1985"

Maneuver load alleviation system

Abstract: A system for reducing wing root bending moment load during aircraft maneuvers. The system operates to reduce the lift on the outboard section of the wing by moving an outboard flap upward in response to commands calculated from aircraft parameters and a predetermined wing root bending moment load limit.

Experimental aeroelastic behavior of unswept and forward-swept cantilever graphite/epoxy wings

Abstract: An analytical and experimental investigation was made of the aeroelastic deflections, divergence, and flutter behavior of both unswept and 30 deg forward-swept rectangular, graphite/epoxy, cantilevered plate-type wings, with various amounts of bending-torsi on stiffness coupling. The analytical investigation used a Rayleigh-Ritz formulation together with incompressible three-dimensional Weissinger L-method aerodynamics for the divergence, and incompressible two-dimensional unsteady strip theory for the flutter. A semiempirical attempt was also made to obtain the steady airload deflections of the wing including the nonlinear stall behavior. Experiments on 13 wing configurations showed divergence and bending-torsion flutter at low angles of attack, and torsion and bending stall flutter at higher angles of attack. Good agreement with theory was found for the divergence and bending-torsion flutter cases at low angles of attack, and for the nonlinear steady wing deflections at high angles of attack. The +15° ply configuration was efficient in relieving the adverse divergence effect of the forward-swept wing.

A windmill rotor with adjustable-pitch blades, as well as windmills with such a rotor

Abstract: In a windmill rotor with adjustable-pitch wings (6) and a nose stay (21) for each wing and intermediate stays (22) between the wings, the new feature is that at each wing the nose stays (21) and the intermediate stays (22) are secured to the outermost end of a generally radial bearing shaft (8), the innermost end of which is secured to the hub (7), and that at the part of the wing root (14) forwardmost in the direction of rotation (13), the wing (6) is supported on an inner (15) and outer (16) wing turning bearing or pitch bearing respectively, placed at the innermost and outermost ends respectively of the bearing shaft (8). With this arrangement, a stable support of the wings (6) is attained, even with relatively weak bearing shafts (8). In an embodiment, the intermediate stays (22) are connected to rigid radial arms (23) on the hub (7). This arrangement relieves the bearing shaft (8) of the tangential forces due to wind and gravity. A windmill with such a rotor is also described.

Wind power propulsion

Abstract: The invention relates to a device for utilising energy contained in onshore and offshore wind, having at least one wing, which can be rotated about an axis of rotation, is arranged at an obliquely raised angle to the horizontal and, if required, is connected to a pylon arranged in such a way as to be rotatable coaxially to the axis of rotation of the wing(s) and the hub of which, which serves to receive the wing root, is connected to associated energy transmission means by a bearing piece. Each wing of the rotor is arranged at an angle beta of about 40 DEG to 80 DEG to the axis of rotation of the rotor, which is aligned at an angle alpha of about 30 DEG to 70 DEG to the horizontal. The bearing piece is rotatable on a frame about a vertical axis or an axis arranged at an oblique angle to the vertical.

Conception of a twin engine ULM

Abstract: 1. An ultralight aircraft of the three-axis airplane type, twin-engined, with separate flight control surfaces, and a rear stabilizing tail structure, which is comprised by : a) wings which are foldable without being dismounted, their joints being placed at the point of attachment to the wing root on the upper part of the fuselage, the folded wings being battened completely against the vertical sides of the fuselage ; b) a rear stabilizing tail structure of annular type, having reduced lateral dimensions, being composed of two horizontal elevators (20, 22) aranged horizontally, parallel to each other, lodged between two vertical and parallel rudders (24, 26) ; c) a system of hyper-sustentation, on the main (bearing) plane only, the outlet of circulating air by internal ventilation of the wing surface being placed behind the median part of the extrados (upper side of the wing surface).