The results obtained during a wake-vortex test conducted in the NASA Ames Research Center 80-by 120-ft Wind Tunnel are described. The wind-tunnel test is part of an FA A and NASA program to study the characteristics of lift-generated vortices in order to safely increase airport capacity for subsonic transports. Data was first obtained to confirm that measurements in the 80-by 120-ft Wind Tunnel are in agreement with those taken in the 40-by 80-ft Wind Tunnel during the test program of the 1970s. Measurements are then presented on the maximum rolling moment induced on following models of various sizes when they encounter the vortex wakes shed by several configurations of a subsonic transport. Finally, measurements are presented of the lift and rolling moment induced on various following models, and of the down wash, as a function of span wise distance in the wake. The wing spans of the followers vary from 0.085 to 1.022 times the span of the wakegenerating model. Nomenclature= rolling moment q = dynamic pressure, pUl/2 r = radius r c = radius of vortex core S -wing planform area t = time U^ = freestream velocity = velocity components in x, y, z directions = distance in flight direction max = spanwise location of maximum rolling moment/6,, y = distance in spanwise direction Z mi ,x -vertical location of maximum rolling moment/6,, z = distance in vertical direction F = bound circulation y = wake vorticity p = air density Subscripts av = averaged over time at a given point / = following model g = wake-generating model

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