Man losing head criticizes safety features on board (9)
I believe the answer is:
taffrails
'features on board' is the definition.
Although both the answer and definition are plural nouns, I don't see how one could define the other.
'man losing head criticizes safety' is the wordplay.
'man' becomes 'staff' (both can mean to work at a particular post).
'losing head' means to remove the first letter.
'criticizes safety' becomes 'rails' (I can't explain this - if you can you should believe this answer much more).
'staff' with its first letter removed is 'taff'.
'taff'+'rails'='TAFFRAILS'
Can you help me to learn more?
(Other definitions for taffrails that I've seen before include "Members in ships" , "ship's bars" .)