Let me guess.. The parents don't believe in spanking?
I'm flying ATA.
Highly unlikely that spanking would have calmed an already worked-up 3 year old....
Actually, though, it's not hard to work up a scenario where these are all nice people, but everything goes bad all at once.
Based on their itinerary, these folks were evidently headed home from vacation, I'd guess that the kid was way past tired, and way outside her "everything as it should be" comfort zone. And if she was visiting grandparents ....
Now add in the likelihood of a bad night's sleep and/or early-morning wakeup, and maybe a bit of stress getting to the airport.
I can see a basically good 3-yo kid melting down in that sort of situation.
Doesn't make the situation any better, but I can understand it.
Nothing wrong w/spanking, but would I be terrible to suggest they should have given the kid some cough medicine or a sip of wine before boarding?