Theres an old conspiracy theory, pre smart phone, that it was about preventing terrorists using phones as missile guidance. Basically, if you see a cellphone jumping 1 tower to the next, you can tell speed by distance and time between towers’ coverage areas.
They didnt want phones on planes creating constant false positives theyd have to verify against flight logs, etc, and obviously didnt want to give enemies ideas ideas, hence the line about interference, but of interference were a likely hazard, theyd be locking up phones for the flight.
It’s not. Hence the conspiracy thing. The pain with cellphones in planes is that they can see the tower, but the tower can’t see them. So they punch the transmission power to 100%. Worse still, they can see not one but probably several dozen towers at the same time, trying to reach them all in hopes one of them can hear them.
Now multiply that by 80 to 200 phones on a plane. This will not interfere with electronic guidance systems or computers in the plane, but will also never actually last for long enough on a cell to establish a connection, but all the requests will busy the tower. So cell towers get briefly radio jammed as the plane flies over them.
You’re conflating two things. One is GPS, which is designed to stop functioning above 1,000 knots to prevent it from being used in a missile.
The other is the interference of which I spoke having to do with electronics like cellphones that operate at harmonics that overlay frequencies used by aircraft navigation systems. It can be demonstrated that they do indeed interfere, but so many things have to happen to make the interference happen it’s wildly unlikely. So many things have changed over the years that prevent this from happening, like cellphones operate at lower power, personal electronics are better shielded, and operate at lower power. On top of that, the aircraft’s RF and EM shielding would have to be damaged in just the right spot, and the electronic device would have to be right near the damage.
As far as cell towers go, most phones are too weak to make a good connection from all but the lowest altitudes, and you’re moving fast enough that it can’t handshake the next tower and negotiate the connection quick enough to have a good connection except maybe st the slowest speeds and altitude on approach for landing.
I did a minor study on this exact subject, but it’s been decades, so the details are fuzzy.
Theres an old conspiracy theory, pre smart phone, that it was about preventing terrorists using phones as missile guidance. Basically, if you see a cellphone jumping 1 tower to the next, you can tell speed by distance and time between towers’ coverage areas.
They didnt want phones on planes creating constant false positives theyd have to verify against flight logs, etc, and obviously didnt want to give enemies ideas ideas, hence the line about interference, but of interference were a likely hazard, theyd be locking up phones for the flight.
And that was/is possible at that height?
It’s not. Hence the conspiracy thing. The pain with cellphones in planes is that they can see the tower, but the tower can’t see them. So they punch the transmission power to 100%. Worse still, they can see not one but probably several dozen towers at the same time, trying to reach them all in hopes one of them can hear them.
Now multiply that by 80 to 200 phones on a plane. This will not interfere with electronic guidance systems or computers in the plane, but will also never actually last for long enough on a cell to establish a connection, but all the requests will busy the tower. So cell towers get briefly radio jammed as the plane flies over them.
You’re conflating two things. One is GPS, which is designed to stop functioning above 1,000 knots to prevent it from being used in a missile.
The other is the interference of which I spoke having to do with electronics like cellphones that operate at harmonics that overlay frequencies used by aircraft navigation systems. It can be demonstrated that they do indeed interfere, but so many things have to happen to make the interference happen it’s wildly unlikely. So many things have changed over the years that prevent this from happening, like cellphones operate at lower power, personal electronics are better shielded, and operate at lower power. On top of that, the aircraft’s RF and EM shielding would have to be damaged in just the right spot, and the electronic device would have to be right near the damage.
As far as cell towers go, most phones are too weak to make a good connection from all but the lowest altitudes, and you’re moving fast enough that it can’t handshake the next tower and negotiate the connection quick enough to have a good connection except maybe st the slowest speeds and altitude on approach for landing.
I did a minor study on this exact subject, but it’s been decades, so the details are fuzzy.