Yes my S 10 mast is just over 17 feet in three sections. I don't have access to the plans but I think stock is three sections of aluminum, but you could do it a number of ways depending on storage or transport issues. Two sections of aluminum and douglas fir CP is good.
I like Alan/Graham's idea of having the mast partner swing out of the way, then you could pivot the mast up and secure it by swinging the partner closed.