On an airplane, a flap is used to lower the minimum speed that the plane can be safely flown at and they also increase the angle of descent for landing. On a sock, the first part does not apply, but a sock flap does indeed prepare your knitting for the dramatic change in angle that is about to happen.
And this sock flap is now done.
Now isn't that just the prettiest thing? A nice turned heel? I still have to pick up the gusset stitches and do the cuff, but from here on in, it is nice comfortable knitting.
Till the second sock, that is.