They found a PLOT to do this but it was not close to fruition
I think you will find that's not quite correct. As a matter of fact, in spite of all the media scare, government propaganda, etc., none of the defendants was found guilty of conspiracy to target aircraft.
As I remember it, they were though, found guilty of an unspecified "conspiracy to murder". Since they didn't have any tickets to board anything, one can only surmise that according to the jury they would have planned to blow something up in the terminal. Like, perhaps, a "security" (excuse the misnomer) queue? Now, can you see the irony here?