Earlier quoted context omitted.
Find My is bluetooth-based, which is fine to use on airplanes as well.
I feel like the BT behavior varies when I activate airplane mode. If I am currently connected to my BT headphones, they stay connected. If I am not, then activating airplane mode appears to turn off BT (pulling out my headphones and trying to connect doesn't work). But I would be surprised if the Find My functionality didn't work in airplane mode, given how Apple set it up to work even when turned off (you must manua…
The same behavior as turning off the phone.