Airlines want Verizon and AT&T to make changes to how 5G C-band is used so planes can land safely

Remember when Verizon and AT&T spent over $68 billion during an FCC auction last year of C-band licenses? These licenses covered mid-band frequencies in the range of 3.7GHz-3.98GHz giving the two carriers the ability to fight back against T-Mobile. The latter picked up 2.5GHz mid-band spectrum when it purchased Sprint for $26 billion and it was helping T-Mobile become arguably the early 5G leader in the U.S.

While mid-band signals don't travel as far as low-band signals do, they travel farther than mmWave. And while mid-band 5G signals aren't as fast as mmW, they are 10 times faster than low-band 5G. So while the odds of you finding a mmWave 5G signal running at 1Gbps is prohibitive, you are much more likely to come across a mid-band signal delivering data at 400Mbps.

Consider that Verizon's mmWave 5G signals, which do not cover much ground, are available to 2 million people. T-Mobile's low-band nationwide 5G is available to 280 million people. Mid-band offers the best of both worlds. It's like Goldilocks. This is the reason why Verizon made a change to include its C-band service under the Ultra Wideband umbrella. Verizon can now say that more of its customers are able to access Ultra Wideband service.

But Verizon and AT&T ran into a problem as some of the C-band licenses it had won at auction were found to interfere with some instruments inside the cockpits of some commercial aircraft. One such instrument is the altimeter which shows how far off the ground an airplane is. Pilots landing a plane in inclement weather often rely on this instrument to land safely. Eventually, both Verizon and AT&T agreed to limit their use of C-band spectrum near airports until 2023. T-Mobile's 2.5GHz mid-band spectrum does not interfere with aircraft.

According to LightReading, the airline industry wants Verizon and AT&T to make some permanent changes such as demanding that Verizon, AT&T, and other C-band operators be banned from pointing their 5G antennas 90 degrees above the horizon. In a filing with the FCC, Airlines for America, Aerospace Industries Association, Regional Airline Association, National Air Carrier Association, and other airline companies and associations wrote that "Reasonable 5G network/equipment limits are feasible and would avoid aviation implementing costly additional mitigations that are unnecessary given 5G's operational use cases."

Verizon is deploying its C-band spectrum, which it uses for its Ultra Wideband 5G service. AT&T hasn't been using its C-band spectrum as much as Verizon has yet. And T-Mobile, which spent a mere $9.3 billion on C-band (after all, it owns plenty of 2.5GHz spectrum) also has been slow to employ it. But in T-Mobile's defense, it doesn't need the C-band spectrum as much as Verizon and AT&T do.

Not everyone believes that the airlines should be able to force changes to how the carriers use their C-band spectrum. Preston Padden, principal of Boulder Thinking and an official with the now-defunct C-Band Alliance, said, "The proposal by the aviation community to codify the voluntary and temporary restrictions on C-band usage graciously indulged by AT&T and Verizon is the most outrageous proposition I have seen in 50 years of following FCC matters.

Padden, who filed with the FCC under his own name and not for an organization or company, stated that "The FCC must just say 'no'."

T-Mobile says that its 2.5GHz mid-band spectrum offers more coverage than C-band spectrum while Verizon says the opposite. Either way, it is important to understand that the C-band airwaves can interfere with commercial flight while the 2.5GHz mid-band spectrum does not. And that alone could give T-Mobile an advantage in areas near airports used by commercial airlines.