So given the advice of those who commented, I have attempted to model this in Polys as opposed to NURBS. You can see my different, and rather meager results here. I am having render issues with this geometry, since it seems to deform rather strangely when I cut out the fantail shape from the model. Here's what I've been doing:
Create a sphere. Cut it in half. Fill hole. Extrude faces with "keep faces together" set to on. (Not too worried about the shape of the front of the resulting cylinder just yet, can clean that up, this is an experiment.) Build a curve detailing the tapered edges and the shuttle bay 'hole' on the rear of the model. Loft a poly surface from said curve. Intersect the cylinder and the lofted surface. Doing so, you get what you see in those two pics.
Any thoughts from the Poly modelers out there?