Goods transporter about to board plane (9)
I believe the answer is:
freighter
'plane' is the definition.
(I've seen this before)
'goods transporter about to board' is the wordplay.
'goods transporter' becomes 'fighter' (I can't justify this - if you can you should give a lot more credence to this answer).
'about' becomes 're' (regarding).
'to board' indicates putting letters inside (inserted letters come on board).
'fighter' going around 're' is 'FREIGHTER'.
Can you help me to learn more?
(Other definitions for freighter that I've seen before include "transport vessel" , "Cargo-carrying ship or plane" , "Cargo ship" , "A plane carrying large load" , "Cargo-ship" .)