These little wing leading-edge fences, or more properly, vortilons, have been seen by many builders on Mike and Sally's Long-EZ, N26MS. Since Oshkosh 84, we have been testing them on several airplanes including the prototype Long-EZ, N79RA. We also received expert assistance from Chuck Richey who installed and tested them on his VariEze, and from Gary Hertzler who did essentially the same thing on his VariEze and from Bruce Evans who installed them on his VariEze and test flew it to Oshkosh. We are pleased to be able to report that the vortilons, as shown here (full sized patterns) are approved for installation on VariEzes as called out.
They replace the leading edge cuff, which should be removed if using the vortilons. There is little or no speed penalty caused by the vortilons, but there is a very noticeable improvement in takeoff and climb performance. Visibility over the nose during rotation for lift off as well as in the flare for landing is greatly improved. Stall characteristics are also improved at all weights to gross and at all c of g conditions from 97" to 102.2".
Webmasters Note: Do not use this electronic document as a template. Dimensions will be incorrect. The installation information given is for VariEzes. The vortilons on the Long-EZ are not as effective as on the VariEze due to the higher sweep angle of the VariEze wing and the different airfoils used on the two airplanes. Vortilons only work on swept wings and will do nothing on straight wings. After considerable testing on 3 different Long-EZs we do not feel there is enough to be gained, to warrant the trouble to install them on the Long-EZ. (Webmasters Note: RAF later changed this recommendation. It is now mandatory to install vortilons on Long-EZs, especially those with a Roncz canard)