The longest I did was the Tokyo->Detroit leg of a Shanghai->Tokyo->Detroit->Toronto flight. It took about 15 hours. But the WORST part was that the flight from Detroit to Toronto was delayed by EIGHT HOURS due to thunderstorms. I could have hitchhiked home in eight hours!
I’ve lost count of the times that I’ve flown between Sydney (SYD) and either Los Angeles (LAX) or San Francisco (SFO) – it’s probably about 20 times each way.
Tokyo to Portland. ~16 hours.
I’ll be damned. I thought Los Angeles - Sydney was at least 24 hours, but according to a quick search it’s only about 16-18.
I did that earlier this year, as part of a trip from Manila to Detroit. We left on Sunday morning, and, 24 hours later, arrived early Sunday afternoon.
And I had to go to school the next day. Ugh.
Vancouver to Sydney, I think it was 20 or 21 hours in the air but I could be wrong because it was a few years ago and the memory is fuzzy.
From Bombay to Newark it was 17 hours. However, it seemed much longer since I was traveling with a clingy 18-month old.
Lufthansa has a nonstop from Munich to San Francisco that I’ve taken several times. It’s about 12 hours. Not among the very longest flights in this thread, but plenty long enough.
Longest nonstop was Washington(Dulles)-to-Munich (or the return). Something like 11 hours. Hardly worth mentioning in this thread.
I still remember Seattle-to-Minneapolis in one of these; sharing the back seat with a duffle bag. Stopped twice for gas, it took most of a day.
Houston to Singapore. I’d route JAL to Tokyo, overnight, then on to Honolulu and LAX, where I’d catch Continental to Houston. Loved flying on JAL; even back in the cattle car, they treated us like kings.
Longest single flight was San Francisco to Hong Kong. 17 hours. At least it was first class on Pan Am, back in the day.
I’ve done that. Then to Minneapolis. So Minneapolis - SF - Toyko - Bangkok — then Bangkok - Taipai - SF - Minneapolis.
Its a full 24-26 hours of travel time, but I think the longest leg is only 12 hours or so.
Atlanta to Recife, Pernambuco, Brazil via San Juan, Puerto Rico.
This was on a Braniff flight back in the 1970s.
It was an overnight flight with no special amenities, and I think it took 13 hours total.
Which is nothing in comparison to the grueling trips that some of y’all have had to endure.
My colleagues are in Cebu, Philippines right now and the flight is Atlanta to Minneapolis to Tokyo to Manila to Cebu. Total time is on the order of 26 hours. It is almost precisely on the other side of the planet from here.
Stockholm to Chicago (followed by a five-hour wait in a sauna-like temperature before the plane for Columbus departed).
I have been told that TAP used to have a direct flight between Lisbon and Macau and as this was a domestic line they didn’t serve any alcohol on board the plane.
Seattle to Atlanta 5.5 hrs of pure hell* :dubious: (it WAS Eastern Airlines)
15 hours and change non-stop from Dubai to DC. Now if you count trips with legs, I’m well over 24 hours. Not fun.
I did South Africa to the United States direct in 2004. I can’t remember the cities involved anymore, but I notice the current Johannesburg to Atlanta flight is number three in the list. I suspect mine was similar.
Slight hijack, but: This is precisely why I love trains. Unless you’re absolutely loaded, a lengthy plane ride is something to be endured. But a lengthy train ride, with a window seat, a glass of wine, and some good music on your iphone, is something to be savored.
Of course, you can’t take a train from NYC to London. So there’s that.
I did something similar, but I didn’t count it for the OP, as it wasn’t non-stop. It was Chicago->LAX->Auckland->Melbourne->Hobart. Something around 24 hours.
I believe the LAX->Auckland stretch was about 13 hours, so that should probably be the longest non-stop for me.
Still, none of these experiences compare to going from L.A. to Chicago on a Greyhound. 50 friggin hours.
In fact, pretty much all the 10+ hour flights mentioned in this thread you couldn’t do by train.
LAX to Sydney, just under 15 hours. The killer was I started in St. Louis and was headed to Perth, coach all the way. What a day(s). Luckily I’m short and I got one of the three seat sections all to my lonesome 
so I could lie down for most of the trip. Not so lucky on the way home, especially since my husband got to fly Business Class (Bastard).
Longest uninterrupted flight would be Sydney to LA.
Longest flight/ordeal would be Auckland to LA, where the we had to turn around because of an electrical problem…this involved an extra hour or so of flying around and dumping fuel. They put us up in a hotel overnight (well, from 1AM until 7AM, anyway) we flew out again the next day, only to have the same problem. So, we flew around for another hour dumping fuel and came back to Auckland. They found room for most of us on the next flight, scheduled to take off 4 hours later. I think the total time from original take-off to landing in LA was almost 36 hours.