If you turn on Airplane mode, the first time it turns off Wi-Fi. But you can then turn Wi-Fi back on. If you couldn’t, pilots flying the plane wouldn’t be able to use the iPads that have their flight plans, charts, checklists, ATC instructions and other critical data on them. And passengers wouldn’t be able to make use of entertainment features on planes, watch the all-important safety messages (complete with advertisements), and pay exorbitant fees to stay “connected” to email, texts and social media while aloft.
The Wi-Fi ON in Airplane mode is a “sticky” feature; the phone will remember the setting the next time you turn on Airplane mode. And if it wasn’t sticky, on each flight probably half the passengers would be complaining to cabin attendants that the in-flight entertainment wasn’t working, instead of just on their first flight.
And, of course, in the event of an in-flight emergency you don’t want the cockpit and cabin crews to fumble around wasting precious seconds trying to figure out why the emergency checklist wasn’t appearing.
And it’s been a sticky feature on all of my iPhones since my first in 2007.