system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How can you pinpoint your location with GPS on your phone without service on the ground, but can’t do the same on an airplane?
gpt
It works in plane too....if you have an unobstructed view of the sky with at least 4 satellites.

Given cramped space and metal ceilinge of typical airliner body this is 50/50 chance of working if you're in window seat.   But if you do it on a private small plane with a big plastic window, it works just fine.