Technically, a QANTAS 747-438, VH-OJ? made an LHR-SYD nonstop, but most extra weight was removed, and only a few airline personnel were on board. To add to that, extra fuel tanks were added. So that really doesn't count.
I remember hearing about an A340-1800. This plane eventually evolved into the A340-500, but as I recall the plane was to be even smaller than the A340-200, but to have longer range. The number comes from the planes ability to fly 18 hours, and easily do Europe-Oz non-stop. The plane was to give up cargo space, and have sleeper cabins on the lower level. Does anyone else remember this plane?
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