The geometry is not fixed, it varies with altitude and aircraft CAT...
- Lewiston - same airfield elevation, Cat C same Category??
I'll try it more simply - can circling area geometry vary for the same airport and same aircraft cat - and how?
EDIT:
RNP charts dont have to deal with this!
- why? Is circling abandoned with RNP charts?
EDIT 2: Shouldn't the Cat C and D be 3 and 4nm?