The most common and most likely answer to this crossword clue is the 9 letter word TAILWINDS
I've seen this crossword clue in The Guardian
T
A
I
L
W
I
N
D
S
More clues leading to the result TAILWINDS
Buddy explains!
The straight part
We know that "gusts coming from behind" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case gusts coming from behind = tailwinds.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 TAILWINDS mean?
TAILWINDS noun- A wind that blows in the same direction as the course of an aircraft or ship