In addition to my contribution above, the honourable mention goes to my sister who flew on BA36 (MAA to LHR) in CW with me. We took off at 8am, we had breakfast and still had 9 hours to go. It’s an odd flight because you leave early in the morning and land at lunchtime, so I find I don’t fancy drinking till just before landing on that one. A bit like the early LHR-JFK departures (BA175 comes to mind, just late enough to tempt me to drink with the second meal).
I told her I’d be taking a nap and wake up 2-3 hours later. I woke up to find that she had polished off a bottle of port and bottle of red, yet was surprisingly sober. The crew confirmed her commitment to the cause.
Perhaps it’s something about the air on the 787 or the South Indian breakfast soaking up the booze, because she’s an absolute lightweight!