Why do i have to turn my phone off on an airplane?
The Real Answer
On most U.S. airline flights, you usually do not have to power your phone completely off — you need to put it in airplane mode or otherwise disable the cellular connection, then follow the crew’s instructions. Wi-Fi can be used when the aircraft has an installed Wi-Fi system and the airline allows it, and airlines may also permit Bluetooth. The rules exist because portable electronic devices and their radio transmissions have to be shown not to interfere with aircraft navigation or communication systems; operators decide what their aircraft can safely tolerate. In short: airplane mode is about controlling radio transmissions, not because one ordinary phone is expected to make the plane fall out of the sky.
You're carrying a device designed to communicate with satellites, and for six hours you're required to convince it that no satellites exist. Your phone isn't the threat — it's your phone's ability to lie to itself that matters.
The Dunce Dynamics Institute Examines Why People Ask This
People ask because the instruction can sound strangely dramatic for a device everyone carries. The real rule is more technical: airlines and regulators control which radio transmissions are allowed because electronic devices must not interfere with aircraft systems, while approved onboard Wi-Fi and other functions can still be used.