Aligning Sketches on Different Planes

[cwilliamrose]

I assume your loft line sketch is above the other two sketches in the feature tree. I also assume the loft line passes through or at least up to your circle sketch planes.

Open the first circle sketch and select the point you want to align to the loft line and the loft line itself. Now look at the constraints list (using a RMB click, menu, etc) for those two selected entities and you should see PIERCE POINT. Apply that constraint, then do the same for the other circle sketch(es).