The Daily Parker

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Happy 2nd Covidversary! And 5G...

Yes, today is the second anniversary of the first confirmed Covid-19 case popping up in Washington State. But that's not what this post is about.

No, instead, I want to highlight two articles about why airlines really do not like 5G mobile networks—at least, not the way the US implemented them:

“TO BE BLUNT,” reads a statement from ten U.S. airline executives, “the nation’s commerce will grind to a halt.” That was in a letter sent to the White House, the FAA and the FCC. “Unless our major hubs are cleared to fly,” it continues, “the vast majority of the traveling and shipping public will essentially be grounded.”

There’s perhaps an element of hysteria and hyperbole in play here, as you’d maybe expect. But there’s also a big problem, and unless things are quickly worked out, the potential does exist for massive flight disruptions.

Most of the issue revolves around a cockpit device known as a radar altimeter (sometimes called a “radio altimeter”). Unlike the plane’s primary altimeters, which measure height above a particular barometric pressure level, the radar altimeter measures height above the ground itself. Essentially it bounces a signal off the terrain below and determines its vertical distance, displayed in feet.

What this interference would actually look like, I’m not sure. Would it be some transient flickering? A failure of the instrument? Whatever it might be, the implications of an outside signal messing with this data, when you’re low over the runway in the fog or blowing snow, hardly need explaining.

The FAA has published a list of at-risk runways; there are hundreds of them. Pilots may not land on these runways during low-vis conditions that require a radar altimeter — i.e. Category II or III approaches — without a special authorization. That authorization comes in the form of something called an “alternative means of compliance,” or AMOC. Two types of radar altimeters commonly installed on Boeing and Airbus models have been judged safe for operation into certain runways. For now, however, this AMOC clearance applies only to around 20 percent of the country’s busiest airports.

The entire thing is a mess. And we saw it coming. Airlines, along with pilot unions and other industry groups, have been sounding the alarm on this for the better part of two years.

How did this happen? Well, the previous administration didn't believe that governments should interfere with business, so no one at the FCC (which approved the 5G implementation) discussed it with anyone at the FAA until the FAA blew a gasket. And yet, in other countries, 5G rollouts haven't caused any of these problems. Maybe because the other countries, with their functioning governments, got the implementation right:

The French antennas have permanent safeguards in airport buffer zones that provide more protection than the US ones. Further, the French antennas near airports have to be tilted downward to reduce interference, and the French antennas have far less power. Not mentioned here but also notable is that in Europe, the C-Band spectrum is in the 3.4 to 3.8 GHz range, so it’s further away from the range that radio altimeters use.

The FAA has a handy infographic explaining this in more detail:

It must be nice to live in a country with a functioning government.

Update: The Times columnist Peter Coy has more about the previous administration's political infighting that led us here.

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