Calling for the rollout delay, the FAA first argued that 5G C-band antennas could interfere with crucial airline equipment. It then went ahead and issued a couple of airworthiness directives (AD) ordering airlines to divert flights under certain conditions, which industry insiders say could cost billions of dollars. “If the AD were applied in arrears to Airlines for America members’ 2019 operations, approximately 345,000 passenger flights, 32 million passengers, and 5,400 cargo flights would have been impacted in the form of delayed flights, diversions, or cancellations,” concludes an Impact Analysis of FAA’s 5G Airworthiness Directive by Airlines for America, shared with Lifewire.
Holding Pattern
In November 2021, AT&T and Verizon agreed to delay the commercial launch of the C-band 5G wireless service until January 5, 2022, after the FAA raised safety concerns about its potential impact on critical airline equipment. As the new date of the rollout approaches, the FAA issued the ADs calling for the revision of flight manuals to prohibit some flight operations that depend on using radio altimeters when in the presence of 5G C-band wireless broadband signals. In a statement to Lifewire, Carter Yang, Managing Director, Industry Communications for Airlines for America, said the ADs from the FAA identify safety concerns that will be “highly disruptive” to the national airspace system and the public. The ADs essentially ask airlines not to rely on radio altimeters when approaching an airport near a 5G C-band antenna and instead divert to another airport. Airlines for America believes the onus for resolving the impasse lies with the telecom companies. “The lack of serious mitigations on the part of 5G telecom companies to address interference issues will significantly disrupt and harm the economy at a time when supply chains are already stretched thin,” reads the Airlines for America Impact Analysis.
False Flag
Michael Marcus, an adjunct professor of electrical and computer engineering at Northeastern University and an independent expert on wireless technology and spectrum policy, told Lifewire in an email that certain radar altimeters are indeed susceptible to 5G in nearby bands. Still, he isn’t impressed by the FAA’s response. “Since [the] FAA let this problem fester, they only recently started collecting data on which models and how common they are,” he said. As a former Associate Chief of the Federal Communication Commission (FCC) ’s Office of Engineering and Technology, Marcus has witnessed situations like these in the past. Calling the adjacent band issues “relatively common,” Marcus pointed to a three-decade-old concern between the use of FM broadcasting just below 108 MHz and an airplane’s Instrument Landing System (ILS) just above that frequency. “The real issue is whether cellular carriers will have the major burden in solving this situation, or the owners of certain models of radar altimeters in aircraft that do not meet reasonable interference immunity standards,” said Marcus.
Middle Ground
Meanwhile, Airlines for America’s Yang said that the group continues to urge the FCC and FAA to work together on a practical solution that will enable the rollout of 5G C-band technology “while prioritizing safety and avoiding any disruption to the aviation system.” A similar view was shared by Meredith Attwell Baker, President and CEO of CTIA, a trade association representing the wireless communications industry in the US, and a former member of the FCC. In a statement issued to Lifewire, Baker said that it was possible to have both safe flights and robust and reliable 5G service. “Despite no credible evidence of a risk to aviation safety, US wireless providers have voluntarily put in place the world’s most comprehensive set of temporary protections. We are working closely with the aviation industry and are on track to join the nearly 40 countries safely using 5G in the C-Band in January,” assured Baker. Things are in limbo now, and it isn’t clear whether the 5G C-band services will be available starting January 5, 2022, or if the rollout will be delayed further as the two federal bodies jostle for one-upmanship.
