Mould old aviator after number one is dropped (5,3)
I believe the answer is:
noble rot
But I can't explain it at all! Could you help me understand?
(Other definitions for noble rot that I've seen before include "Mould useful in making some wines" , "Mould contributing to certain rich wines" , "Grape-shrivelling mould" , "Mould on grapes used for certain wines" , "Mould that beneficially affects grapes" .)