trying to follow the Spitfire tut
when making the wings I create 2 curves with the ep curve tool, rebuild the curves, then loft ...

it seems output is already polygon geometry (instructions say to convert nurbs to poly) and when extruding faces I get top and sides but no bottom on object.
have deleted and retried a dozen times all with the same result

anyone have an idea what i`m doing incorrectly?

TIA