It is safe to use your cellphone while flying

Well, eternal topic yeah, but…I’m about to say it: “It is safe to use your cellphone while flying”. Please, public prosecutors, do not come after me just for having said a truth, it is safe, for the people onboard. However, it is very, very costly for the ones on the ground, or, at least the government and the Telcos. But, how?

First, let me introduce myself, José María Seguí, MSc in Telecom Engineering, Entrepreneur and super-frequent Traveler. And yes, I sometimes let my cell on with no plane mode, when flying.

Why is it safe to use it?

So, the thing is all these communications: WiFi, cellphones, TV, Radio,…. travel on different frequencies, different modulations, and different codifications (if you WANNA learn what these mean, I strongly recommend THIS BOOK). And, the ones for the communications with the Control Tower at airports (the only ones necessary on an airplane), travel on different waves, in all three domains.

I’ll try not to get too engineer, but, please, for the frequency, have a look at this graph from FCC when they were auctioning a new band for cellphones.

Image result for radio cellphone spectrum control frequencies
Image taken from The Boston Globe, when a new cell frequency was being auctioned

What is the problem with flying cellphones though?

But do not get me wrong, there is a problem, but not for you up high, rather for the ones down there.

If you keep your cell signal on when flying, and, especially in the slot of the path that the airplane is close to the ground, the Cellphone network has to reconfigure to give you service.

Yes, it is the same thing as if you were in a really fast car, it would also happen that you would switch cell (“antenna”) every few kilometers, or every few meters if you’re in a high density area like a city.


Be good, and turn your cell signal off before taking off to avoid destroying the ground world’s communications while you’re flying (even if just you wouldn’t be a problem)

However, if you see somebody on the seat next to you with their signal on, don’t call them assassins. Everybody has left a switch turned on at home by mistake and nobody died for that. This is kinda the same

Want more reasons?

As an interesting example, the agency prohibiting the usage of cellphones in the US is the FCC (Federal Communications Commission), instead of the more logical FAA (Federal Airlines Authority).

And yes, that means the problem is to the ground communications, not the airplanes’!

Image result for airport cell phones
Yeah, we all use cellphones like crazy at the airport

Imagine airplanes crashing close to your boarding gate because you took that last call before boarding? Just do not! It´s not happening!

Have you ever thought about what would happen to taking-off airplanes if it was really dangerous, and they do it in front of million-people crowded terminals, using their cells like hell?

Again, It is safe to use your cellphone while flying, so Chill out, and enjoy your journey…