You’ve heard it a hundred times: “Please switch your device to airplane mode.” But have you ever wondered what actually happens if you don’t?

Airplane mode disables your phone’s ability to send or receive wireless signals — including cellular, Wi-Fi, and Bluetooth. In theory, this prevents electromagnetic interference with an aircraft’s navigation or communication systems.

But here’s the twist: modern planes are heavily shielded, and the chance of a smartphone disrupting equipment is extremely low. So why the rule?

It’s more about preventing signal overload. When hundreds of phones are trying to connect to ground towers at high speed and altitude, it creates signal noise — both for your phone and telecom infrastructure. It can also cause your device to rapidly drain its battery trying to keep a connection.

Another reason: it reduces radio noise in the cockpit, especially during takeoff and landing — the two most critical phases of flight.

So no, your phone won’t crash the plane. But yes, it’s still a good idea to follow the rule.