It’s a funny thing. The signals from a dozen or so phones are not a problem for a plane. But, there have been no formal safety ratings on hundreds of phones using cellular service while in-flight. It’s even probable that there is no interference from everyone using cellular networks, but they don’t trust aircraft safety to “probable”.
So, they tell people to turn on flight mode and trust in the 90% who do as asked. Don’t worry about the 10% on their phones, they’d ban phones in the cabin if there was any doubt at all.
It’s a funny thing. The signals from a dozen or so phones are not a problem for a plane. But, there have been no formal safety ratings on hundreds of phones using cellular service while in-flight. It’s even probable that there is no interference from everyone using cellular networks, but they don’t trust aircraft safety to “probable”.
So, they tell people to turn on flight mode and trust in the 90% who do as asked. Don’t worry about the 10% on their phones, they’d ban phones in the cabin if there was any doubt at all.