In-Flight Flow Visualization Results from High Angle of Attack Tests on a Forward Swept Wing Aircraft with Comparisons to Water Tunnel Results
Asymmetries in the vortical flow generated by the long forebody of the X-29 aircraft were suspected of causing uncommanded yawing moments at high-angles of attack. A smoke flow visualization technique was used to visualize the forebody vortices and to correlate any asymmetries observed with flight yawing moment data. This paper presents a method of analyzing smoke flow visualization data for comparison with asymmetric aircraft moments or forces. Good agreement was found between the forebody vortex asymmetries and uncommanded yawing moments.
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