How to construct the heel?

 From:  Gregor (GBZH01)
6261.3 
Hi Michael

I could not manage to draw curves that give me a planar surface and matches the sole. I did it now like that. First revolved the backside of the heel, made a planar surface on the bottom. Then I made a blend from one open heel edge to the other. Finally, I copied the sole surface and trim it with the heel surfaces. Then I got my solid.