The holidays are here and for many of us that means flying across the country to see family or – if we’re lucky – around the world to escape winter. In either case, boarding a plane in the US means being greeted with the familiar instruction to put portable electronic devices on airplane mode or turn them off altogether.
The rationale for this policy has long been that cell phones can disrupt aircraft systems. But the EU lifted its long-standing ban on mobile phone use on planes in 2022 – so why do Americans still have to use airplane mode?
Richard Levy, an aviation consultant who worked for decades as a pilot for American Airlines and is now an instructor for Southwest Airlines, says the FAA’s official position remains that cell phone signals can interfere with aircraft communications and navigation equipment. (The FAA simply referred to it Popular science to the regulations which require passengers to follow safety instructions from all crew members, and made no further comment.)
The word ‘could’ clearly does a lot of work in that sentence; what is the actual risk? Levy says that in modern aircraft the risk of interference with navigation equipment is minimal. “In the latest Boeings and Airbus aircraft,” he explains, “the navigation equipment [relies] on GPS, same as in cars. And I’m not going to tell you what the odds are [of cell phones interfering with that system] are zero, but they are almost zero.”
As for communications equipment, it is instructive to look at the FAA’s guidance on this matter, contained in Advisory Circular 91.21-1D on the topic “Use of portable electronic devices on board aircraft.” This document provides some insight into the FAA’s thinking on this issue – especially the “History” section, which explains that the ban “was established in May 1961 to prohibit the operation of frequency modulation (FM) receivers because they were determined to operate aircraft navigation and communications systems.”
At the very least, this makes perfect sense, as aircraft communications frequencies and FM radio broadcasts both use a very similar portion of the VHF region of the electromagnetic spectrum. In most parts of the world (including the US), FM radio uses frequencies between 87.5 MHz and 108 MHz, while aircraft communication frequencies are used starting at about 120 MHz. So it’s absolutely possible that someone trying to listen to a transistor radio in the cabin could cause problems.
However, cell phones use much higher frequencies than FM radios. The cellular band with the lowest frequency reaches the lowest point 698MHzand modern 4G And 5G networks usually use frequencies in the GHz range. So it seems extremely unlikely that cell phones could cause any problems or air communications. The FAA itself has already commissioned two studies 2006 and one inside 2012– which found no evidence that mobile phone signals interfere with aircraft systems.
Yet there are anecdotes about telephones interfering with communications equipment. A pilot earlier this year described on TikTok how he had experienced interference in wired headphones, which he said felt like “a mosquito” in his ear. “If you have a plane with 70, 80, 150 people on board,” he said, “and even three or four people’s phones try to connect to a radio tower for an incoming phone call, it sends out radio waves. . There is a risk that these radio waves could disrupt the radio waves of the headset that the pilots are using.”
What does Levy think about this? “Prove to me,” he says, “that.” [the pilot] know it was a cell phone [causing the interference]. It can be all kinds of things that cause the static electricity. I am very sceptical.”
So why is the US so reluctant to lift the ban? Several commentators have theorized about the “real” reasons for US authorities’ intransigence on this issue, reasons that have less to do with science and more to do with pragmatism: GizmodoFor example, predicted earlier this year that the ongoing ban on mobile phone use is ‘all about air rage’. (This idea is supported by the 2012 FAA study, which called for public comment on this issue – 79 of 148 comments received were against lifting the ban, and “the dominant concern expressed in these comments was that voice conversations from passengers using their mobile phones would annoy and distract other passengers.”)
Does Levy give any credence to such ideas? “I do,” he says. “You and I have been in a supermarket and someone is talking way too loudly. They mean no harm, just talk calmly, or go to your car, or go to a park. Of course, on an airplane, such an escape is not possible, and the idea of being stuck in the middle seat for hours between two people talking loudly about their startup ideas sounds like a whole new circle of hell.
Levy also suggests that authorities may see inattention as a problem: “Another reason why they don’t want people using mobile phones on the road is that [they] want passengers to pay attention to the flight safety briefing.” For what it’s worth, he has less time for this argument: “The Europeans have safety briefings too, and people pay attention [to those].”
What are the chances that the ban will be lifted? Levy says passengers should not hold their breath. The ban on the use of mobile phones is not left to the discretion of airlines; it is recorded in two separate titles of the Code of Federal Regulations (specifically Title 14relating to aviation and space travel, and Title 47that pertains to telecommunications.) The former is issued by the FAA and the latter by the FCC, meaning that two federal agencies would have to decide to change their respective positions on the issue.
The FAA and FCC are not the only powerful organizations opposed to any policy change; Levy suggests that unions may also be happy for things to remain as they are. In the commercial aviation industry, he says, “unions [still] have a lot of authority. I don’t know if the airline employee unions are petitioning the FAA [retain the ban”, but if so, they have a lot of lobbying power.”
However, he says, ultimately the issue is that “the US is very conservative in this way. My guess is that they’re waiting for data somehow to prove [definitively] that there is no risk.”
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