14 hours, United Airlines IAD-GRU back in August.
We were all boarded and seated...then nothing happened. After awhile the captain announced that there was another delayed flight with 26 pax, and we were waiting for them.
10 minutes later he announced that they found a hydraulic leak in the tail and were investigating it. 20 mins after that he announced that we couldn't fly due to the leak, and we were all deplaned..it was roughly 1130pm by this point.
All the pax of course had to line up at the CS desk to get a hotel and make arrangements for missed connections from GRU. Finally got to the hotel about 1am, stood in line behind all the other pax put in that hotel. A few hours sleep, and back again the next day to the airport. As many of us had checked luggage, we were wearing the same clothes.
I can tell you, by the time we reached Sao Paolo, that plane stank!