Designs aircraft cutting energy (5)
I believe the answer is:
plans
'designs' is the definition.
(design can mean a plan or map)
'aircraft cutting energy' is the wordplay.
'aircraft' becomes 'plane' (plane is a kind of aircraft).
'cutting' means to remove the last letter.
'energy' becomes 's' (I can't justify this - if you can you should give a lot more credence to this answer).
'plane' with its last letter taken away is 'plan'.
'plan'+'s'='PLANS'
Can you help me to learn more?
(Other definitions for plans that I've seen before include "Intentions or drawings" , "Schemes; diagrams" , "Aims" , "Stratagems" , "Detailed proposals for doing something" .)