when everything seems to be out of control, you're on a verge of getting crazy, mad at something, but you can't cross that line. so yes, it's agreeable to fly and leave everything, means that going up, to the sky, but not dead, you don't want to be dead yet ^^. picturing that the sky above is vast, wide and sure is big enough for the writer alone. the writer wants to be empty as the sky, pretty much means to unloaded his troubled mind.
another thing that you want to do when you're facing trouble is running away. the writer also wants to run until his feet are hurt. run as fast and far as we could seems would be a great thing to do. i remember forrest gump, when he run and run because the girl he always loved, jenny, leaved him. gump stopped running because he felt tired, and perhaps he's feeling a bit okay after what happened to him. so this line also emphasizing, the writers determination to forget about something.
after the writers effort to ignore the things he used to have, he wants to cool it down, and relax for a bit, by saying sleep for a while and speak no words. a moment to be alone, to rest, the outcome or the goal after it, is you'll wake up fresh, and feeling much more better than before. but why in australia?
i think maybe because manic street preachers is british, if they want to go in a holiday, they would prefer to go someplace warm ^^
