Fig. 4. A velocity traverse performed at mid-height and mid-plane, using a pitot-static probe, with the equivalent wind speed at 10 m s^-1. Boundary-layer effects on flow velocity were not apparent until within 1 cm of the left and right walls of the working section. Filled circles, traverse of left side; open circles, traverse of right side. Note that the width of the flight chamber at mid-plane is 121 cm, 1 cm greater than at the inlet, to accommodate thickening of the boundary layer along the length of the flight chamber. Left side and right side are referenced looking forward from inside the flight chamber.