Here's the real reason to turn on airplane mode when flying

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We're all familiar with this routine: “Make sure your seat is in the upright position, tray table is stowed, curtains are up, laptop is stowed in the overhead bin, and electronic devices are set to airplane mode.”

Now, the first four are reasonable, right? The curtains need to be drawn so we can see if there is an emergency, such as a fire. The tray tables need to be put away and the seats need to be upright so we can get out of our seats quickly. Laptops can become projectiles in an emergency because the back seat pockets are not strong enough to contain them.

And the phone needs to be set to airplane mode so it doesn’t cause an emergency on the plane, right? Well, that depends on who you ask.

Aeronautical navigation and communications rely on radio services, which have been coordinated to minimize interference since the 1920s.

The digital technology used today is much more advanced than some of the older analog technology we used 60 years ago. Research shows that personal electronic devices can emit signals in the same frequency bands as aircraft communications and navigation systems, creating what is known as electromagnetic interference.

But in 1992, an independent study by the Federal Aviation Administration and Boeing investigated how the use of electronic devices interfered with aircraft and found no problems with computers or other personal electronic devices during non-critical phases of flight. (Takeoff and landing are considered critical phases.)

The FCC has also begun creating reserved frequency bandwidths for different uses, such as mobile phones, aircraft navigation and communications, so that they do not interfere with each other. Governments around the world have developed the same strategies and policies to prevent aviation interference issues. In the EU, electronic devices have been allowed to continue to be used since 2014.

So, now that these global standards are in place, why does the airline industry continue to ban mobile phones? One of the problems is something you might not expect – ground put one's oar in.

Wireless networks are connected by a series of towers; if passengers flying over these terrestrial networks were all using mobile phones, the network could be overloaded. The number of passengers flying in 2021 exceeded 2.2 billion, which is half of the number of passengers in 2019. Wireless companies may have a point here.

Of course, when it comes to mobile networks, the biggest change in recent years has been the move to new standards. Current 5G wireless networks are favored for their higher-speed data transmission, causing concern among many in the aviation industry.

RF bandwidth is limited, but we are still trying to add more new devices. The aviation industry pointed out that the 5G wireless network bandwidth spectrum is very close to the reserved aviation bandwidth spectrum, which may cause interference to navigation systems that assist aircraft landing near airports.

Airline executives are worried about your phone's 5G network. Here’s why (2021)

Airport operators in Australia and the United States have expressed aviation safety concerns related to 5G deployment, but the rollout appears to have raised no such issues in the EU. Regardless, it would be prudent to limit cell phone use on airplanes while we address 5G issues.

Most airlines now offer customers pay-as-you-go or free Wi-Fi service. With new Wi-Fi technology, passengers could theoretically use their phones to make video calls with friends or clients while in flight.

On a recent flight, I spoke with a flight attendant and asked her what she thought about cell phone use during flights. She said it would be inconvenient for cabin crew to wait for passengers to finish calling to ask if they wanted a drink or food. On a passenger plane with more than 200 passengers on board, if everyone is on the phone, in-flight service will take longer to complete.

For me, the issue with using your phone on a plane is more about the social experience of having 200+ people on the plane talking at the same time. In an age where disruptive passenger behavior, including “air rage,” is on the rise, in-flight cell phone use could be another trigger that changes the entire flying experience.

Disruptive behavior can take many forms, from failure to comply with safety requirements (such as not wearing seat belts), to verbal altercations with other passengers and crew, to physical altercations with passengers and crew (often considered air rage).

In summary, the use of mobile phones during flight does not currently affect the aircraft's ability to operate. But crews may not want delays in providing onboard service to all passengers — there are many people who need service.

However, 5G technology is eating into the radio bandwidth of aircraft navigation systems; more research is needed to answer 5G questions about navigation interference during aircraft landings. Keep in mind that when we discuss the two most critical phases of flight, takeoff is optional but landing is mandatory.