Ships not completed -- take flight (4)

I believe the answer is:

flee

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'take flight' is the definition.
('flee' can be a synonym of 'take flight')

I can't explain the rest of the clue.

(Other definitions for flee that I've seen before include "Maybe escape" , "Take flight" , "Do a runner" , "Take to one's heels" , "Abscond" .)

I've seen this clue in The Telegraph.

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