taper in catia v5

[falcons]

i have made two sections of airfoil in generative surface design in catia at some distance. In multi-section surface command , following error is displayed---


Multi section surface1.
Sweep operator
The extrusion of a surface leads to a cusp.
Use a guide with a smaller curvature.

Please someone help in correcting this error.

 

[Matt G.]

 

[yellow_submarin]

 

[Kestas]