Airman crashes in harbour (6)
I believe the answer is:
marina
'harbour' is the definition.
(I've seen this before)
'airman crashes' is the wordplay.
'crashes' indicates anagramming the letters.
'airman' anagrammed gives 'MARINA'.
'in' acts as a link.
(Other definitions for marina that I've seen before include "Berthing area for yachts" , "where yachts moor" , "part of harbour?" , "Harbour for pleasure yachts and small boats" , "Base for pleasure boats" .)