I’m not new to Keto but I’ll be travelling for the first time on this lifestyle in a few months and It will be a 15-hour flight. I just checked the dietary choices from the airline and laughed a little bit and said to myself… “I got this… I’ll just keep hydrated and fast for 24 hours.”. Eat some cheese if needed 
I always select regular, and then, when it arrives, I eat the protein & veg, use the butter to spread all over the protein, and reject everything else. Sometimes I eat the salad, too, if it’s done correctly.
You can also buy food in the airport and eat it inflight. Don’t bring food from home in your carry-on. The security folks will make you throw it out.
I stare at the same list every time 
I end up fasting most flights though.
We did longhaul from Amsterdam to Lima last year, I took a bag of macadamias and some “babybel” cheddar cheese. I took their water and black coffee but was perfectly fine with what I had taken. When I refused the final meal of the flight the stewardess was very concerned that I was ill! lol
I had bought some brazil nuts and pecans for thew return trip but I slept through most of that so only ate a small amount of what I’d bought.
Yeah, you’re better off bringing your own. The worst test for me is when they walk by with the snack basket. It’s pure carbs. Even peanuts are out these days.
I sometimes bring a baggy of pork rinds.
Personally, I generally would just fast (I’m not motivated enough to haul food around, with the exception of the travel size Bulletproof Brain Octane C8 Coconut Oil) but totally understand if you are vacation with your family. I’d also try to avoid alcohol (it messes with your sleep) but again hey if your on vacation…
Fasting while travelling is the best way to reduce jet lag. I watched an experiment on tv once they did with athletes who flew regularly for events and they compared effects of eating vs fasting. Fasting won hands down although hydration was very important too.
@Daisy, did the athletes who were given a meal in flight eat the typical SAD diet, or keto/low carb?
Good question. Don’t know. It will have been what was available on the plane so not great. They were athletes so they will have been health conscious. My guess would be certainly not keto but not SAD either - maybe somewhere in between?
I’d love to see the experiment repeated with fasting versus keto eating, in fat adapted passengers. I prefer keto eating, and in the past 2 years done on average one international Long haul flight per month for business. Did both fasting and eating. I find stress (cortisol) rises during fasting, and in combination with travel (potential additional stressor) it is not the best combination for me. Again…for me…as in n=1. I maintain the same IF protocol (eat once every 24 hours), and drink mineral water in flight (like Perrier, club soda, Pellegrino, whatever they have) to get electrolytes. I guess people need to test and see what is best.
Agree. I also found travelling and eating on business class made a huge difference! I was very spoilt last year with a visit to see my dad in Thailand and went business - very low stress!