I saw this recently on New York Times – How 5G Clashed With an Aviation Device Invented in the 1920s: https://www.nytimes.com/2022/01/19/business/5g-radio-altimeters-airlines.html. Longer article.
By Stephen Gandel January 19, 2022
The potential for interference between 5G signals and the radio altimeters long used by pilots has divided the telecom and aviation industries.
A technological innovation that helped pilots fly fighter planes during World War II is now at the heart of the dispute between airlines and AT&T and Verizon over 5G, an innovative service meant to speed up mobile devices.
The clash has been years in the making and came to a head in the last few weeks. AT&T and Verizon agreed on Tuesday to restrict 5G near airports after airlines warned that potential interference from it could cause a crucial device on planes to malfunction, and force them to cancel flights. Even with the airport restriction, a number of international airlines on Tuesday canceled flights to the United States, though some of those flights were restored.
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