The introduction of 5G was supposed to change how humanity uses mobile internet. From providing low-latency connectivity for mobile phones to making things like robotic surgery possible over long distances, 5G has the potential to be an invaluable tool.
On paper, it sounds like the perfect plan, but now that companies have begun to roll out the technology, a new challenge has appeared. Can 5G communications interfere with aviation instruments? Here’s what is known now and what the implications could mean for flight.
Mobile internet has been available as part of a communication network since the early 1980s and has moved through several generations — hence the G in the name. Each generation operated on a different frequency band as part of the electromagnetic spectrum. It started on the AMPS network, at 800 megahertz (MHz), but those have since been replaced with the two major networks — CDMA and GSM — that dominate today’s market. Currently, AT&T and T-Mobile operate GSM networks, and Verizon and Sprint are on CDMA.
The frequencies for the different networks and the services they provide can vary, depending on systems and locations, but for the most part:
- 3G mobile internet operated on 850 and 1,900 MHz frequency bands. T-Mobile also had some operations on 1,700/2,100 MHz bands. This has almost been entirely phased out, with the final 3G network — T-Mobile/Sprint — shutting down operations in 2022.
- 4G mobile internet operated on 600, 700, 850, 1,700/2,100, 1,900, 2,300 and 2,500 MHz frequency bands.
- 5G mobile internet operates in both the MHz and gigahertz bands (GHz), including 600 and 850 MHz, and 2.5, 28 and 39 GHz range.
The 3.7-4.2 GHz frequency band, known as the C-Band, is entirely dedicated to mobile internet. Before the introduction of 5G, this band didn’t see a lot of traffic, and what it did see was primarily related to satellites in orbit. As more 5G towers go up and an increasing number of people adopt the technology, this frequency band will likely become incredibly crowded, which is where the problems begin to creep up.
It can sometimes be difficult to separate facts from conspiracy theories for those trying to learn more about 5G and its impact on the world. Any search about the topic leaves the user steeped in paranoid delusions about 5G-enabled vaccine shots and an endless parade of websites claiming it will be responsible for the end of days. While most of this is hot air without any basis in reality, there is a new problem emerging that seems to be directly related to the introduction of 5G — and it could have serious consequences.
Aircraft altimeters measure the distance between the aircraft and the ground, enabling pilots to navigate safely. These work by monitoring radio frequencies in what is known as the “highway lane” just above 4 GHz. That precisely matches up with the 5G C-Band frequency that will get more clogged with traffic. All sorts of aircraft — from commercial airliners and small private craft to military planes, helicopters and some UAVs — have radar altimeters that could be affected.
While the potential for problems is there, the FCC doesn’t seem too concerned. It has actually dismissed these issues, clashing with the FAA and other experts who believe they could cause crashes that result in multiple fatalities.
There are several ways to approach this problem, including many that are already in place. AT&T and Verizon have both offered to reduce the power to their 5G networks as a way to reduce the risk to aircraft in flight. Six different former FCC chiefs have voiced their frustration, stating that the agencies should work together instead of remaining at odds with one another.
The trick here is to ensure that aviation and telecommunications advances happen in parallel. If the latter begins to take off and leave the former behind, pilots could be hunting for a new way to tell how high they are when they fly, and that sort of interference could ground most or all aircraft around the globe.
While the potential for 5G interference in aircraft is there, it is too early to project how impactful this frequency overlap could become. Engineers may end up taking 5G back to the drawing board, as it’s just getting started to ensure it does what it is supposed to without grounding every single aircraft on the planet. This will be of paramount importance.
5G is going to change the world — this is an irrefutable fact. What remains to be seen is how these changes will manifest and how they will impact the lives of the average individual.