looking into the le some more puts me back to where i was previously. if you take the naca definition of a circle at the le, it is only tangent to the ellipse at one point (the leading edge rail start point). it looks like the tangency points i thought i was getting were a small error with the moi snap points. moreover, i am getting false intersection snap points at times. doing another comparison and ignoring the false snap points, there really is no intersection of the two. the naca le circle really has nothing to do with the ellipse definition either. i thought it might, but am not seeing it upon further review. so this leaves me where i was originally. you can use the conic section as the le and just flat out ignore the naca definition. or you can use the naca le definition and figure out some sort of curve to transition from the circle to the rest of the naca points. at this point, i am content to leave things as they are. i am satisfied with the conic/ellipse le and using all the naca data as through points. when i compared the two options previously the differences were small.