This
IS an old thread, but since it has been brought back I'll throw in my 2 cents. I did do a set of articles describing how to do this in Blender, mainly to generate structural skeletons for models. I tried to keep it as generic as possible so as to be applicable to different situations. I really don't do ships, but I picked a ship for the example because basically in a sense a hull is hull even if you call it a fuselage or rocket body. I'm not a Blender guru by any stretch, but the method has worked for me on different projects. In many ways it isn't really different from the traditional solid model carving method used in Old Timey solid models (The kind where you take a block of balsa and just draw the profiles onto the block and work your way down).
Constant Variation: Mod Mon: a Blender Hull for Bulkhead Generation
Constant Variation: Mod Mon: Creating Bulkheads from 3D model (II)
And after a lot of hunting (cause the links are down) off Ken Horne's Solid modeling page the
Scale Model Aircraft Construction Procedure Manual which details how you do this in balsa. Ken Horne is listed as a member here, so maybe he can fix his links (a lot seem to be going to a dead server).