What isn't aluminum?
I know the frame on Airstreams is steel and can rust / needs rust prevention. What else below the belt line?
When the curve starts down where it transitions from aluminum to black/grey, is that all steel? All of those white painted lower side access cubbies like where the fresh water / black tank flush etc are and where the steps go into, isn't that all steel?
Seems like from my research those areas are the first places to start rusting out and need protection. Anyone know why Airstream just didn't use aluminum below the belt line also? Cost?