How 5G technology affects commercial aircraft (and why US airlines speak of imminent danger)

If you have ever had to fly by plane, you will know that this is one of the main safety rules of airlines when getting on one of their aircraft.

And it is that, despite the fact that technology advances by leaps and bounds and that new devices come out every day to make our lives easier, all the devices we use are limited by the basic physical principles that govern the universe.

For example, the waves that your cell phone emits and receives are radio waves and move in the same electromagnetic spectrum used by radios and aircraft antennas. The only thing that changes is the frequency on which they are transmitted.

It is this basic principle of physics that explains why it is better not to use your phone on a plane: by preventing the use of mobile phones in the air, the aeronautical authorities seek to minimize the chances that the waves that reach your phone interfere with those reaching the aircraft’s navigation equipment.

And while this is a very basic explanation of a fairly complex process, it also helps explain why airlines in the United States have asked the country’s cell phone providers to delay the rollout of fifth-generation (5G) technology by nearly certain airports.

5G and airplanes

At the end of 2020, the United States Federal Communications Commission (FCC) opened an auction to offer telecommunications companies licenses to operate in the so-called “C band” of the electromagnetic spectrum.

Band C is the one used by cell phone providers to deploy 5G, a technology with which they seek to expand speed and cell coverage throughout the national territory.

During the auction, the FCC managed to award more than US$80 billion in licenses.

The problem is that within the frequencies that were auctioned, there were blocks in the frequencies from 3.7 to 3.98GHZ, which are very close to those used by the radio altimeters of some aircraft.

These devices operate on frequencies between 4.2 and 4.5Ghz.

That is why, more than a year after the auction and a few hours after the telephone companies roll out their 5G networks in band C, the airlines warned that the country could be facing a “possible massive interruption in the transport of people and goods”.

5G “everywhere, except near airports”

With the deployment of 5G networks in band C set to start on January 19, some of the main airlines in the country sent a letter to the FCC, the Federal Aviation Administration (FAA) and the Secretary of Transportation expressing their concerns .

“We are urgently writing to request that 5G be implemented nationwide except within approximately 2 miles of affected airport runways,” argued the letter, signed, among others, by the presidents of American Airlines, Delta and United.

“The knock-on effects on both passenger and cargo operations, our workforce and the economy in general are simply incalculable,” the document argues.

Concern expressed by airline companies prompted two of the largest US cell phone carriers, AT&T and Verizon, to announce they would delay the rollout of 5G networks near airports.