Sorry to poke holes in a theory but the FBW systems on airbus airplanes do not know how to ditch. They are very good at keeping the airplane in a flyable condition (not stalled, not an unusual attitude, etc.) but their are no flight control modes or programs for this situation. This one goes straight to pilot skills, a pretty sturdy airframe and a whole lot of good luck.

- Eric
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You are never beaten until you admit it. - - General George S. Patton