Fuel gets fliers flying initially when in distress (8)
I believe the answer is:
paraffin
'fuel' is the definition.
(paraffin is a kind of fuel)
'fliers flying initially when in distress' is the wordplay.
'fliers' becomes 'RAF' (Royal Air Force).
'initially' says to take the initial letters.
'when in' is an insertion indicator.
'distress' becomes 'pain' (I've seen this before).
The first letter of 'flying' is 'f'.
'raf'+'f'='raff'
'raff' inserted inside 'pain' is 'PARAFFIN'.
'gets' is the link.
(Other definitions for paraffin that I've seen before include "Petroleum product" , "Possibly oil" , "Waxy flammable substance" , "Fuel oil obtained from petroleum or coal" , "Flammable wax" .)