Mike,
I'm not knocking the whizz wheel,which I think is brilliant!
One of the instructors is a professional pilot and he says he still uses it for most things.
I realise it's a circular slide rule,great for nav calcs on the wind side,and great for most other stuff on the calc side but I don't know how to use it for accurate calcs with large numbers or several places of decimal points.
I will ask the CFI about large number calcs when I'm next there,as I can't see how to work them from the instructions.
Lister