Having used fibreglass for many, many years and seen how the UV from the sun and general weather affects it, I suggest those so-called designers who left the leading edges of these blades unprotected should be committed to an institution. Sticking a bit of body filler on them won't last 5 minutes.
They do, for about 10m on a 45m blade at the bottom. The blades are made from fibreglass but have a thick gel coat over it to protect it and the filler is a special 3 part set up so it’s tough and designed for the elements.
