Researching the Cruise Potential of the Arc Wing VTOL Concept

The Bertelsen arc wing VTOL is an attractive concept for general aviation due to its mechanical simplicity and relatively low cost. Work to realize the performance potential is ongoing. The hover efficiency of the multi-element arc wing in VTOL mode has been demonstrated in tethered tests of a large powered model. It remains to characterize the arc wing in the cruise configuration. While the unique arc wing geometry effectively captures the flow from a large propeller, the radically anhedral wing challenges the intuition as to what behavior to expect in forward flight. An electric-powered radio-controlled model has been built to explore the cruise performance of the rigid arc wing. The preliminary results of that effort are the subject of this paper.