From:  Bowl of Soup (WILKINSLAFLAMME)
2048.4 In reply to 2048.3 
Not that I am a pro, but the front edge of your main airfoil seems to intersect the fuselage at a very tight angle, I suspect the filet radius on that kind of geometry would be the issue. Dont forget that filets are a way to save time for designers, but at the end of the day, if you are actually planning on using this model to make an aircraft, you probably want to fully control the interface between those two b-reps so that you can better control the aerodynamics of that structure. If your just doing this for fun, try opening up that front interface angle and reducing your filet radius.

Hope this helps,