5G, Telecom vs Aviation: who is right?

Not sure this belongs in GD, but it sounds like a hotly debated topic elsewhere, at least, and there might be opinions on both sides of the issue here as well.

Emirates president: The 5G snafu is the biggest screwup I’ve witnessed in my career (msn.com)

Speaking to CNN’s Richard Quest today, Emirates president Tim Clark said that they were not aware of the issues until yesterday morning “to the extent that it was going to compromise the safety of operation of our aircraft and just about every other 777 operator to and from the United States and within the United States.”

Transportation regulators had already been concerned that the version of 5G that was scheduled to be switched on could interfere with some airplane instruments, and many aviation industry groups shared those fears — despite reassurances from federal telecom regulators and wireless carriers.

In December, the FAA issued an urgent order forbidding pilots from using the potentially affected altimeters around airports where low-visibility conditions would otherwise require them. That new rule could keep planes from getting to some airports in certain circumstances, because pilots would be unable to land using instruments alone.

So apparently it’s a dispute between “federal telecom regulators and wireless carriers” on the one hand, and the FAA and “many aviation industry groups” on the other, with the stakes being the ability of airplanes to land safely. Who is right? And if in fact there is the risk of interference, whose job was it to make sure that didn’t happen.

I’ll answer the last question.
The FCC.

FQ thread here:

Who is right? Or, who is in the right?

It seems to be a fact that the high-powered US-style 5G towers will interfere with some airplane equipment on some models in a way that could be dangerous.

Should the airlines (or Boeing) have updated the equipment? Should the FCC have told the carriers to lower their power? Is that what you’re asking?

It seems like the FCC is the main source of screwup here.

I was asking both, actually. (Perhaps should have said “correct” instead of “right”, and the final sentence should have had a question mark.)

The point is that the FCC is apparently maintaining that it’s not an issue, and the FAA disagrees, so the first question is who is correct about that. Given that it is an issue, the next question would be whose responsibility it would be to deal with it in some form or other. Your responses are “the FAA” and “the FCC”, respectively. Thanks.

My layman’s view is that there is likely fault with both agencies, and that this issue should have been addressed, collaboratively, by the two of them long before this week’s rollout date.

What I heard on NPR (no cite, not sure what the speakers credentials/affiliation was) was that its only a problem with landing and take off, and only with somewhat older planes. so that itcan be solved in the short term by not allowing 5G towers within a certain radius of airports and in the long term by upgrading/retiring older aircraft.

There are screwups all over the place, but in my view it’s largely the FAA and the airlines at fault.

The 5G rollout plans were known for years (since 2018, IIRC). It’s not like any of this should have been a surprise to anyone. The FAA is having a hissy fit because they failed to do anything about these plans. Was this an intentional ploy to delay things? Maybe, or maybe just incompetence.

The FAA has managed to approve a high fraction of aircraft/altimeter combos already, so their initial claims that this will ground airflight to a halt were obviously exaggerated. Most likely, this number will go up to some very high fraction, say 99%, over time. That will leave only some ancient and basically defective altimeters as problematic. And even then, it will only affect some categories of operation.

As a very general rule, FCC certified devices must accept interference from outside their authorized bands. The altimeters here run from 4.2 to 4.4 GHz. They are complaining about interference from 5G devices in the 3.7 to 3.98 GHz range. That is very far away, spectrally speaking. Although the FCC should try to find a short-term compromise, ultimately these altimeters need to be replaced.

A good, recent article on the subject:

The FAA and airline industry does not look good here. Among other things, Boeing agreed years ago that a 100 MHz guard band was sufficient. The FCC gave them a 220 MHz guard band. And now, the FAA is complaining (or was complaining… the story changes by the day) that even a 400 MHz guard band is insufficient.

The FCC can only do so much arm-twisting to get the airlines to adhere to the things they agreed to.