John D. Bird, Donald R. Riley
A technique for obtaining a physical picture of the flow behind a wing, combination of wings, or other aircraft components is described. This technique involves photographing from a far downstream the action of a large number of tufts of uniform length mounted on a screen. This procedure permits obtaining, in an approximate fashion, an important result of a pitot-yaw-head survey; namely, a vector plot of the flow field in a plane normal to the air stream at a station downstream of an aerodynamic surface.
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