Many naval architects use Rhino for design and engineering - there are extra modules you can get - http://www.rhinomarine3d.com/
You can also get flattening and nesting modules for steel or wood construction - I know a company using Rhino in combination with Maxsurf and SolidWorks to design steel boats for which they supply the plasma cut kits for boatyard assembly.
RhinoMarine's cross sectioning features are by far the slowest on the market, so I would recommend some other program.
Check out TouchCAD instead, which offers far superior shape control, very fast dynamic cross sectioning, full push-pull modeling from any view, integrated marine calculations, automatic weight and center of gravity calculations, and integrated dynamic unfolding / nesting features. TouchCAD direct exports NURBS surfaces /solid NURBS surfaces directly to VW. Works on both Mac and Windows. TouchCAD costs less than Rhino Base costs, and if you add RhinoMarine it is nearly three times as expensive as TouchCAD.
Quote from a professional marine designer and TouchCAD / VectorWorks user in Canada:
"The TC demo has been great. Here's an example of a funky proa I played with yesterday. There was a round hulled version, but I tried rounded box sections for a change. I am truly amazed at how easy and fun TC is. This is what I got into boat design for in the first place! A recent small canoe project demonstrated how great TC is. What takes only about 7 minutes to model in TC, took almost 2 hours in MaxSurf! I couldn't believe how slow the process was."
www.touchcad.com