Hmm, maybe so. I wonder if a piece of Lexan to "fill" the space inside the arc would help smooth out the airflow. Or, if that's a totally stupid idea. Of course it's all idle speculation at this point.My initial mindsim, performed while grasping an old school slide rule and invoking the spirit of Kelly Johnson, is that a lot of slower moving turbulent in the inner arc will produce a lot of lift as the faster moving air on the outer arc becomes turbulent at the bottom, making any fins on the back nearly useless.