@lostinthepast We did it at that age with no screens on the way there, but on the way back we had a little bit of ms Rachel that we watched, (I think?) I'm not sure we did need it.
It was good to have just as a backup. We do very occasional screens (like when we are all sick, last time was probably March or so)
Lots of new (to him) toys, suction cup spinner, post it's and tape, dollar tree stuff, plastic slinky, animals... I brought him to dollar tree a week or so before and he picked out some things, whatever cought his attention was packed an not seen until the flight. He picked some shiny metallic pom poms. Eventually started pulling them apart on the plane but still he was quiet and occupied and I had a trash bag.
I had about 10+ different ziplock bags to pull out when he started to get bored, each with a different set of toys. Small bags, not a lot of toys in each, but very very well organized, easy to pull out and put back. Same with snacks. Lots of varied snacks, packed separately so not much is lost if accidentally dumped (or thrown).
It felt a bit crazy overkill when I was packing, and we didn't use everything, but that was great because we had some new toys for the flight back. I think this particular trip was 2 flights and a layover, so longer than what y'all are doing.
And the best thing I ever learned: a roll of dog bags and one of those little containers so it doesn't unravel. We have one attached to each diaper bag and stroller we use, and another in the car. Ever convenient trash bags.
Tiny container of bubbles for waiting in lines or in the airport. They do make them small enough for TSA, dollar tree usually has them in a set, (next to the wedding stuff when I bought it) target, Amazon. The suction cup spinner was also good for layovers, attached to a window or chair, or even just hold it.
Lots of hand wipes.