mike it is possible because its been done before....as for how its done is a different question i believe the fsds v2 has an option where you create a elevated landing surface after creating a transparent poly of the deck surface.. maybe this might lead u in right direction.. many other scenery design programs have this feature too although im only a novice at scenery design at the moment
hope this helps
Helpful, although i'm not paying 70$ for FSDS