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.
KeywordsFlow Visualization Angular Position Vortex System Local Timing Standard Side Force
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