Thought of this cos done a couple in the last 24hrs :-( I'm on 5.41, but a classic example of defining the word starts around 6.20. The pilot describes one major fuck-up........FUBAR!!
Was the first time i'd heard it, but understand it comes from the German word 'Furchtbar'

Like when you try to save some money on a tune up and, in the process of doing it yourself, break your distributor body and, in the process of putting in a new distributor got the timing all out of place so the car won't run and breaks down twenty miles from home in the middle of the night. In that instance you would tell the towtruck driver "Well, I guess I fubar'd that damn thing (At least that's what I told my tow truck driver when I did it).

Sgt, that weapon is FUBAR!

That dude was on pills, smoke, drink, and some more s**t!! He was fubar. Couldn't function or anything!!

anything to do with the military is fubar

This thing is fubar man

It's my last night in town, so let's get FUBAR tonight