Navy almost making escape (4)
I believe the answer is:
flee
'escape' is the definition.
(I've seen this in another clue)
'navy almost' is the wordplay.
'navy' becomes 'fleet' (I've seen this before).
'almost' means to remove the last letter (almost the whole word is kept).
'fleet' with its last letter removed is 'FLEE'.
'making' is the link.
(Other definitions for flee that I've seen before include "Take to one's heels" , "Run (from danger)" , "Do a runner" , "rush" , "Abscond" .)