UAV Aerial Refueling - Wind Tunnel Results and Comparison with Analytical Predictions

Abstract : Results from a wind tunnel. test of a delta wing UAV behind a KC-135R are presented and compared with predictions from a planar vortex lattice code. Both the predictions and data show wake interference effects on the UAV that vary significantly with relative lateral and vertical position, and weakly with relative longitudinal position. Predicted trends are excellent for all force and moments except for drag, and magnitudes are reasonably well predicted. The distribution of lift between the tanker wing and tail is shown to have a strong effect on the receiver aerodynamics.