A rotor blade used primarily for a helicopter which has airfoil sections and an overall configuration of a particular shape is described. The upper surface of the airfoil section is shaped such that there is a general reduction in the surface slope from the leading edge to the maximum ordinate at approximately 35% chord. Behind the termination of positive slope, the upper surface slope is negative and decreases continuously to a position of about 70% chord, at which point the surface slope increases continuously to the trailing edge. From the point the lower surface leading edge fairs into the lower surface, the lower surface slope is negative and increases continuously to approximately the 44% chord. The lower surface slope is positive and increases continuously to about the 65% chord, aft of which the positive slope decreases continuously to about the 75% chord. The positive slope then increases continuously from 75% chord to the airfoil trailing edge. The rotor airfoil is shaped to maintain desired values of pitching moment coefficient over a wide range of lift coefficients and increase the drag divergence Mach number, resulting in increased power efficiency and blade stability.
Family of Airfoil Shapes for Rotating Blades
1982
23 pages
Report
No indication
English
Family of airfoil shapes for rotating blades
NTRS | 1983
|Family of Airfoil Shapes for Rotating Blades
NTIS | 1982
|