Ground Effect - Theory and Practice

The conclusion of a previous article by Pistolesi is that the increment of lift due to ground effect is largely attributable to the effect of induction of the free vortices, and is practically equivalent to a virtual increase in aspect ratio. The ground clearance was of the order of magnitude comparable to the wing chord. New reports by Le Seur and Datwyler treat the case of minimum distance from the ground and is confined to the plane problem only. The author briefly reviews these reports and also one by Timotika. References to all the reviewed reports are in the attached bibliography.