Hello NG-members,

I'm considering an ATS and I'm trying to define the right measurements,
particularly the luff-length.
Are there any rules of thumb that apply here?

What luff-length is appropriate with a forestay-length of 20 meters?

What is the difference in height (re the luff-sheet-eye) between
sailing the ATS a) downwind and b) slightly upwind ?

Thanks and fair winds,

Len.