If you want a hard plane to build, you should try the Spruce Goose( aka H-4 hercules) or perhaps some of my designs in the Google Sketchup 3D warehouse. (there is no real need to make the Hughes H-1, as it is already in FMS, unless you wish to make an alpha model of it) Here is the link to my sketchup designs.
http://sketchup.google.com/3dwarehouse/ ... revstart=0
Just to inform you, Sketchup can export bitmap images, so you can have the plans just by putting the view mode into parallel projection, then going to camera, then going down to main views, and picking any of the views aside from "iso".