The most common and most likely answer to this crossword clue is the 7 letter word BOMBING
I've seen this crossword clue in The Times
B
O
M
B
I
N
G
Buddy explains!
The straight part
We know that "Air strike/failing completely" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case air strike/failing completely = bombing.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 BOMBING mean?
BOMBING verb- To attack using one or more bombs; to bombard.
- To fail dismally.
- To jump into water in a squatting position, with the arms wrapped around the legs.
- To sound; to boom; to make a humming or buzzing sound.
- To cover an area in many graffiti tags.
- To add an excessive amount of chlorine to a pool when it has not been maintained properly.
- To make oneself drunk.
- (especially with along, down, up etc.) To move at high speed.
- The action of dropping bombs from the air.
- The action of placing and detonating bombs.