The most common and most likely answer to this crossword clue is the 7 letter word EMBARKS
I've seen this crossword clue in The Guardian
E
M
B
A
R
K
S
Buddy explains!

The straight part
We know that "takes flight" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case takes flight = embarks.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does EMBARKS mean?
EMBARKS verb- To get on a boat or ship or (outside the USA) an aeroplane.
- To start, begin.
- To cause to go on board a vessel or boat; to put on shipboard.
- To engage, enlist, or invest (as persons, money, etc.) in any affair.