Sailors were around when Eva broke this flier's heart (5)
I believe the answer is:
raven
'sailors were around when eva broke this flier's heart' is the definition.
'raven' can be an answer for 'flier's' (raven is a kind of birdanimal). I am not sure about the rest of the definition.
'when eva broke this flier's heart' is the wordplay.
'when' becomes 'r' (I can't justify this - if you can you should believe this answer much more).
'broke' indicates an anagram.
'this flier's' becomes 'wings'.
'heart' means to look at the middle letters.
The centre of 'wings' is 'n'.
'eva' with letters rearranged gives 'ave'.
'r'+'ave'+'n'='RAVEN'
Can you help me to learn more?
(Other definitions for raven that I've seen before include "pig" , "Large black bird" , "Flyer" , "Big black bird" , "Passerine bird" .)