Rarely has an arcane interagency dispute proved so needlessly disruptive.
On Dec. 5, wireless carriers had expected to begin rolling out 5G, the next standard for cellular networks, on a critical new frequency known as the C-band. The deployment promised increased bandwidth, faster transmissions, wider range, and many new possibilities for wireless devices and apps, potentially turning a useful technology into a transformative one.
Enter the bureaucrats. In November — at the last minute, and after years of detailed planning — the Federal Aviation Administration objected to this process. It warned that emissions from the C-band could interfere with radio altimeters onboard aircraft. It suggested that 5G manufacturers and operators conduct added tests on their equipment and hinted that further "mitigation" measures could be on the way, including flight restrictions in dozens of locations.
On its face, the FAA's concern isn't unreasonable. Altimeters calculate an aircraft's altitude, help pilots land in limited visibility, assist in avoiding midair collisions, and inform numerous other safety systems. The FAA identified 17 onboard functions that could be at risk if an altimeter were subjected to harmful interference. If 5G actually threatened such equipment, the consequences could be dire.
Yet the Federal Communications Commission studied precisely this risk for years before approving the deployment. Some 40 other countries have authorized the use of 5G in the C-band, without a single report of harmful interference. Moreover, the U.S. deployment includes a "guard band" — or empty space between wireless and airplane frequencies — of 220 megahertz, which is up to twice as large as in comparable countries such as Japan.
Six former heads of the FCC said in a recent letter that the FAA's position "threatens to derail the reasoned conclusions reached by the FCC after years of technical analysis and study."
They're right. The FAA's position is based almost entirely on a single technical report that, as wireless groups have pointed out, relies on flawed methodology, implausible assumptions, and extreme testing standards to reach a conclusion that contradicts years of careful study by regulators and industry stakeholders.
More to the point: Real-world data from across the globe yields no evidence of a significant threat. In an effort to ease this impasse, trade groups from the telecoms and aviation industries have agreed to share data. The FAA and FCC insist that they're working together as well.