Early take-offs from Delta, easyJet, Monarch...oh, and BMI...put out of action (5)
I believe the answer is:
demob
'out of action' is the definition.
Although both the answer and definition are verbs in their base form, I cannot see how one could define the other.
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for demob that I've seen before include "Release from army" , "soldier's release" , "Disband troops" , "removal from service" , "Leave the army" .)