5G has so far been mostly a battle on Earth. On the one hand, operators who want to deploy their networks as quickly as possible to monetize their licenses. On the other hand, citizens, and some local authorities, were concerned about the possible consequences of this technology on health. At the same time, another fight is going on around 5G, in the air. Aircraft manufacturers fear interference with radio altimeters, which gives rise to investigations in which Switzerland is taking part.
On Tuesday, the leaders of Airbus and Boeing thus alerted the US Department of Transportation to possible disturbances to instruments on board their aircraft by 5G. Jeff Knittel and David Calhoun have expressed their “concerns”: They suspect 5G will interfere with radio altimeters, instruments onboard planes that measure ground clearance.
France takes action
They are just suspicions. But they reinforce those issued in February in France by the Directorate General of Civil Aviation. The latter then claimed that “the use of 5G devices on board aircraft could lead to risks of interference leading to potential errors in altitude measurements”. Errors “particularly critical during the instrument landing phases”, warned this authority, which obtained a reduction in the power of emissions from 5G antennas near 17 airports in France. French authorities also recommend putting 5G devices in the cabin in “airplane mode”.
The letter from Airbus and Boeing comes at a key moment: US carriers Verizon and AT&T were initially supposed to start using the 3.7-3.8 GHz frequency bands on December 5, before delaying this launch to January. .
Reviews in Switzerland
These issues are also valid in Switzerland, where 5G was deployed in 2019. Since then, thousands of antennas have been activated nationwide by Swisscom, UPC Sunrise and Salt. The authorities are investigating and also criticizing the attitude of the builders. Contacted on Wednesday, the Federal Communications Office (Ofcom) indicates that “studies of potential interference with radio altimeters by 5G are still ongoing in the European group competent in the matter, PT1 of the ECC (IMT Matters) to which Switzerland actively participate.” And Ofcom points out “that there has been a certain delay in these studies due to the fact that the aeronautical industry has so far been quite reluctant to provide all the technical data of the various radio altimeters used. The next meeting of this group of experts will take place in mid-January and will allow for the continuity of the studies.”
A priori, the risk of interference between the 5G used in Switzerland and aircraft altimeters is low, even very low. “To date, no disruptions have been reported in Switzerland or Europe. The 5G frequencies used in Switzerland are in the 3.5 to 3.8 GHz range. As a reminder, radio altimeters operate in the 4.2-4.4 GHz frequency range, which is therefore relatively distant,” continues an Ofcom spokesperson. Also contacted by The weather, the Federal Office of Civil Aviation (FOCA) specifies that “in Europe, the frequency bands used for 5G and those used by aviation radio altimeters are somewhat further apart compared to the frequency bands used in the US. The European Communications Committee (ECC PT1) study will tell whether in Europe we have to deal with the potentially negative effects of 5G on radio altimeters.”
Recommendations in Switzerland
So the story is probably not over. OFAC goes on to say that it has released a document, called the Safety Awareness Notification Data, “warning airlines, operators and pilots of potential interference from 5G emissions on radio altimeters.” This document includes nine defined recommendations on this subject. One of them recalls the importance of “reporting any possible anomalies or incidents through the aviation incident notification system”.
That’s not all: looking at this document, it reads: “If 5G-enabled portable electronic devices are to be carried in the cabin or cabin, they must be configured not to transmit on cellular networks (e.g. in airplane mode) or be off.” It is therefore the same recommendation as in France. Furthermore, this document states that “for essential communications, such as during emergency medical services operations, teams should only use 3G or 4G communication devices”.
The three Swiss operators have not yet received instructions to reduce the transmission power of 5G antennas near airports. And changing frequency bands hardly seems possible. “The allocation of frequency bands is a long and complicated process that is decided on an international level and a possible change is not an option”, says Ofcom to Climate.