Im modeling a helicopter fuselage with a boundary surface. Its setup like a loft (previously it was) with closed loop "profiles" and open loop "guides".

The problem I'm having is the intermediate profiles which are being generated are getting concaves on the sides and tops. This is easiest to see in the front view. The corners are not necessarily tangent to the sides and tops. All the direction parameters are default, i.e. global/none. changing any of these parameters only seems to make things worse. Except that if I change the direction one (profiles) curve influence to "next sharp" the intermediate profiles straighten up, but the intermediate profiles of the direction 2 curves (guide curves) gets really wacked. There is also some concavity along the guide curves as veiwed from the top. There are 6 profiles and 4 guide curves.

Can anyone provide any guidance here?