“What’s 5G got to do with airplanes? Not much, argue the wireless carriers hoping to deploy the technology. But the FAA says it’s worried that C-band could interfere with some radio altimeters, aircraft safety tools that rely on nearby airwaves. The agency is so concerned that it’s been fighting to delay 5G deployment and has issued guidance that could cause flight cancellations from airports operating near certain 5G antennas, meaning that anyone who flies or has one of these devices could be affected.
Just hours before the launch of the new 5G signals, Verizon and AT&T also agreed to delay the rollout of C-band within two miles of certain airport runways, though the expansion of 5G service will go forward everywhere else. The latest compromise came just a day after the CEOs of 10 of the largest US airlines wrote to Pete Buttigieg warning that the “nation’s commerce will grind to a halt” due to the FAA’s new rules.
“This agreement will avoid potentially devastating disruptions to passenger travel, cargo operations, and our economic recovery, while allowing more than 90 percent of wireless tower deployment to occur as scheduled,” said President Joe Biden in a statement on Tuesday. “This agreement protects flight safety and allows aviation operations to continue without significant disruption and will bring more high-speed internet options to millions of Americans.”To keep disruptions to a minimum, the FAA is analyzing how individual altimeter models work when C-band is turned on. The agency said on January 16 that it had approved two altimeters used in many Airbus and Boeing airplanes, which cleared about 45 percent of the US commercial airline fleet to fly when these new 5G frequencies are turned on.”
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“The problem is altimeters rely on parts of the spectrum that neighbor the airwaves used by the C-band. In a nightmare scenario, the FAA thinks that signals sent over C-band could interfere with these altimeters — specifically older altimeters — creating a potential safety issue. Meanwhile, the Federal Communications Commission already determined that 5G would not pose a problem for modern altimeters, and similar 5G technology has already been deployed in Europe with no issue.”
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“the FAA is continuing to lift restrictions on aircraft, one by one, as airlines prove their altimeters can work when C-band is turned on.”
https://www.vox.com/recode/2022/1/12/22878622/5g-airplanes-c-band-interference-faa