Yet another blow to the 5G. After human health, it is the turn of aircraft guidance systems at airports which risk being disrupted by 5G technology. This is the concern raised by major airlines in the United States.
Does the deployment of 5G threaten the aircraft guidance system? The siting of 5G base stations near US airports is the subject of strong opposition from the country’s air transport sector. The industry regulator, the Federal Aviation Administration (FAA), and local companies are concerned that aircraft altimeters, an instrument that helps pilots determine their altitude and distance from other landing craft in particular, are jammed by the frequencies of the antennas of the new mobile network.
The dispute escalated further this week, as carriers were to activate 5G across the country. The leaders of a dozen companies did not hesitate to speak of “chaos” to warn against the risks that this could represent for the safety of passengers and American air transport more broadly. The operators AT&T and Verizon had to postpone the deployment in the face of the threat of the companies to cancel several hundred flights supposed to pass through airports located near the new antennas. Before the announcement of the postponement, several foreign companies had already announced flight cancellations.
The power of 5G antennas could blind aircraft guidance systems
These airlines, including American Airlines, Delta Airlines and United Airlines, rely on a report from 2020 which challenged the American telecoms regulator on possible interference between certain 5G frequencies and instruments on board aircraft.
In question, the C frequency band (between 3.7 and 4 GHz), which must be used by the new 5G network, whose spectrum is very close to that of the frequencies used by aircraft altimeters (between 4, 2 and 4.4 GHz). Even if there is no risk of direct interference, the transmission power of 5G antennas could pose a problem for certain altimeters likely to be interfered with by these nearby frequencies. The American regulator of air transport evokes possible blinding of aircraft guidance systems likely to alter the precision of the altitude measurements communicated to the pilots in situations of bad weather conditions.
The FAA has so far validated the use of certain radio altimeter models and given its approval for 48 of the 88 American airports most directly affected by the risk of interference. But the terms of a final agreement are still far from being established between the airlines and the telephony giants.
In France, transitional precautionary zones and conclusive tests at this stage
The situation is different in France, and more widely in Europe, where 5G, already in service in some countries, uses radio frequency bands farther from the bandwidth used by aviation, in this case, a band oscillating between 3.4 and 3.8 GHz in France. And the question of the possible disturbances caused to the aviation sector was taken into account several months ago.
To guard against the risk of interference with aircraft altimeters, “ protection zones have been set up around 17 major French airports applying precision landing procedures in all weathers”, explains the General Directorate of Civil Aviation (DGAC), which had expressed initial reservations about the installation of antennas near airports. In these areas, the transmission power of 5G antennas is limited by the four French telecom operators who are prohibited from directing their antennas towards approaching planes.
Studies are also being carried out in parallel to assess the impact of emissions from 5G antennas on aircraft guidance instruments. ” At this stage, no event of disruption by 5G technology of the proper functioning of the radio altimeters has been reported to the DGAC by French operators. This issue is also being addressed at European level and France is coordinating closely with the European Union Aviation Safety Agency (EASA)”, underlines the DGAC. The ANFR also specified to BFMTV that the tests of the main altimeters of the planes had not shown the slightest problem for the time being.