What's the longest flight you've been on? Why on earth?

I can't imagine lasting 24-plus-hours without sleeping, of which 20-odd would be at 30,000 feet above the Pacific Ocean!

See that's something that most people wouldn't think of when talking about the longest flight they've been on. The idea, of course, remains quite romantic - to be in a record-breaking flight. But why on earth would you want to be confined to your seat - a seat - for almost an entire day? A 19-and-a-half-hour non-stop flight doesn't only break records. It is good enough to break your spirit and soul. To bruise your body and mind - and ego. In all honesty, I haven't taken the world's longest flight - the pilot of which Qantas just undertook from New York to Sydney. I've not even come close to it. The max I've done is 14-odd hours, from Dubai to John F Kennedy in an Emirates A380. It was not bad, and when I say 'not bad', I mean that someone else was paying for the Business class seat I was in and my body did not creak, crumble or crack at the end of the journey thanks to the lavish seats and leg space. But I was still close to my breakpoint - physically and mentally.
This particular flight was what Qantas is calling a 'survey flight' - without the bells and whistles of a fully functional commercial flight. The brand-new Boeing 787-9 used for the flight is not equipped to complete the 16,200km journey on full load; so, it took off with just 50 passengers, four cabin crew and six pilots on board, and without any cargo. And yes, there were medical experts on board to monitor the passengers' sleep and food consumption patterns and to take care of medical emergencies, if any.
I'm one of those who can't sleep on a flight for love or money. Whether it is the three-something-hour flight from Dubai to New Delhi or the seven-and-a-half-hour journey to London - or even longer ones - I just can't catch a wink in the air. I either end up red-eyed (shorter-haul flights) or with a massive jet-lag (the longer ones), but never peppy or perky like some of my colleagues. I'm a personification of exhaustion, stress, fatigue all rolled into one. I can't imagine lasting 24-plus-hours without sleeping, of which 20-odd would be at 30,000 feet above the Pacific Ocean! This wasn't even a space flight (come to think of it, the UAE's very own Hazzaa Al Mansoori took six hours to dock at the International Space Station)! Non-stop sounds good, but would you risk a crushed body, a subdued mind and a rickety body clock when you could take a break and split the journey into two comfortable ones?