Some high hopes are born between Verizon and AT&T that new bands of C-band cellular radio spectrum will help bring the 5G hype closer to reality; however, the large mid-band 5G rollout could have a side effect.
As such, the side effects of the large mid-band 5G rollout include when planes rely on radio altimeters to show how high they are above the ground to land safely when pilots can’t see. The FAA is now asking 6,834 of them not to do this at some airports due to 5G interference.
“We are engaged with the wireless operators, as well as our interagency partners, to do everything possible to make sure the mitigations are tailored to prevent disruptions,” an FAA spokesman said.
In addition, the FAA ruled on Tuesday that those thousands of U.S. planes (and some helicopters) will not be able to use most guided and automatic landing systems designed to operate in poor visibility conditions if they land at an airport where there is considered interference sufficient for their altimeters to be unreliable.
“Landings during periods of low visibility could be limited due to concerns that the 5G signal could interfere with the accuracy of an aircraft’s radio altimeter, without other mitigation measures,” an FAA spokesperson said.
The FAA ruling does give airlines and pilots an out — if they can prove their airplanes have altimeters that are protected or are otherwise not going to be affected by interference.
Therefore, Verizon and AT&T have agreed to delay the launch of the C-Band by one month (until January 2022) and have also offered to recall the power of 5G towers for six months after that to address concerns.
The carriers and their lobby group, the CTIA, have suggested there is no valid reason to fear interference, but the FAA has so far not been convinced.
It’s still unknown which airports might restrict low visibility flight, but airports might be in the same places where the carriers are deploying mid-band 5G, with a few exceptions.
As of December, the planned rollouts are supposed to be in 46 markets designated as Partial Economic Areas (PEAs).
One solution is a band filter for those altimeters, but organizations like the Radio Technical Commission for Aeronautics (RTCA) have warned that it might take years to certify them and retrofit all the planes.