Defining jet lag as something like moving across time zones fast enough to get one’s body clock significantly out of sync with local time: who, or at least when, would the first case have been?
I would imagine travel by train or car would not be fast enough for long enough to do this. I guess a journey would need to cross at least 4 timezones to cause it, but I’m not sure how fast you’d have to go.
This is still a rather subjective question but I would vote for this person:
"First Jet Aircraft to make a non-stop Transatlantic Flight
February 21 1951. An RAF Canberra B Mk 2 (serial numbe WD932) flown by Sqd Ldr A Callard, became the first jet aircraft to make a non-stop transatlantic flight when it flew from Aldergrove, Northern Ireland to Gander, Newfoundland. The flight covered almost 1,800 miles in 4h 37m. The aircraft was being flown to the U.S. to act as a pattern aircraft for the Martin B-57."
Icarus? 
Could it not be true that the first person to suffer from “jet lag” not necessarily have traveled by jet?
Well, it could be “prop-plane” jag, but I think you have to consider it as due to powered air travel. Travel by train, boat, or balloon probably wouldn’t get you across enough time zones in a day to make the difference in time an issue. It wasn’t until people could gain or lose multiple hours (trather than just one) that this would make a difference in their internal schedules.
Yeah the average person adjusts at about one hour per day to jet lag, so they’d have to travel across at least two time zones to feel any effect (and that’s pretty mild.) At the equator you’d need to travel about 3000 kms to cross two time zones, as you get closer to the poles though the distance becomes smaller.
I would’ve thought the first people to suffer from jet lag would be those carrying out some of the pioneering long distance flights early in the twentieth century.
Whoops, forgot about this thread! I put it down to jetlag - really.
Lindy flew from New York to Paris in 33.5 hours and they are 6 hours apart in timezone. By Death Ray’s formula of an hour a day that gives him about 4 hours’ lag, but I rather doubt he noticed that after having been sleepless for that period.
Shagnasty’s nomination covered 3.5 hours time changes in 4.5 hours which gives them about 3 hours’ lag so I think that would definitely count.
oddly enough, I changed 15 hours twice in the past 5 days and got in yesterday. siberia was really beautiful but hours and hours of a frozen wasteland
any US to europe plane flights by a crew would have noticeable jet lag pre-dating Lindy. probably NY to LA - especially in the morning, but you probably had the same minor effect on one of the record breaking coast to coast trains
slight hijack, IMHExperience, day per time zone adjustment is too little when travellers transpose night and day. takes up to a week to feel decent & two weeks to be fully in the zone. ambian is your friend.
Maybe I’m misunderstanding you, but transposing night and day is a timezone change of 12 hours which would take about 12 days to adjust to, that agrees with your experience.
At any rate, the hour per day thing is a rough guide and it varies greatly between individuals.
You can’t really do a 15 hour change either. As far as your body is concerned it is a 9 hour change.
But note that Lindbergh was actually the 104th person to fly across the Atlantic. (His flight captured public fancy and became famous because it was done solo and went much further than any previous effort - New York to Paris.) The first non-stop flight was by John Alcock & Arthur Brown in 1919 - they did Newfoundland to Ireland in just under 16 hours.