Aircraft seen in quiet country roads? (6)
I believe the answer is:
planes
'aircraft' is the definition.
(I've seen this before)
'quiet country roads?' is the wordplay.
'quiet' becomes 'p' (music symbol for 'piano', ie soft or quiet).
'country roads?' becomes 'lanes' (I've seen this before).
'p'+'lanes'='PLANES'
'seen in' acts as a link.
(Other definitions for planes that I've seen before include "Flat surface in Naples" , "Aircraft and tools for smoothing wood" , "Jets maybe" , "Trees" , "Those flying" .)