Hello,
There is a very neat feature in Catia called "Extremum point", by which you can insert extremum/maximum point on a curve such as an airfoil.
So if you select an extremum point along the length of the airfoil, you get the point exactly on the leading edge which you can use to (1) split the airfoil/wing in half precisely and (2) use as a perfect guide rail..
I have attached a screenshot from Catia.
thank you,