3Ds max (Gmax) landable surfaces

I've been looking through the forums but havn't been able to find anything relating to creating landable surfaces in 3ds max or Gmax, is it possible or will I need to use a different programme for the surface? If it is possible to make them in 3ds max or Gmax alone could someone please either explain how or just post a link to any tutorials covering the subject. Sorry if its a bit of a noob question but I havn't been able to find anything to help me. Thanks a lot.