Flier hurt in a crash on the quiet (6)
I believe the answer is:
thrush
'flier' is the definition.
(thrush is a kind of birdanimal)
'hurt in a crash on the quiet' is the wordplay.
'in a crash' is an anagram indicator.
'on' is a charade indicator (letters next to each other).
'the quiet' becomes 'sh'.
'hurt' is an anagram of 'thru'.
'thru'+'sh'='THRUSH'
(Other definitions for thrush that I've seen before include "Common British songbird" , "Brown songbird" , "Common garden bird" , "Bird - fungal disease" , "Singing bird or mouth-troat infection" .)