LAXLHR wrote:

720B wrote:

FAA to prohibit many flight operations due to risk of ‘5G’ wireless interference


https://travelandaviation.com/faa-to-pr ... ence-news/

The moves come as US wireless communications companies prepare on 5 January to start, in 46 markets, transmitting in the 3700-3800 MHz range – the “C-Band”. That range is too close to the 4200-4400 MHz range used by aircraft radio altimeters, the FAA says.

As I read all of this, and some links, all I can think about is if it can interfere with aircraft, what about our bodies? We will have the answers fairly soon for sure.

I find it amazing that the FAA and FCC did not discuss this...but then again, why would they?! haha.

You raise an excellent point.

We have spectacular views, but unfortunately live near a cluster of three cell phone towers.

The National Radiation Laboratory used to test at selected properties in the area, including our own, which over the years showed a steady increase in both peak and average exposures.

5G is expected to be a step up. Unfortunately the mobile companies have refused to continue funding the tests.

I wonder how much radiation in flight wifi or even a home wifi router creates compared to the radiation coming off a cell tower? and I know a lot of in home wifi routers are now using 5G as well (the new one i got when we switched to fiber optic a few weeks ago is 5G)

zeke wrote:

The RADALT TSO does have requirements for frequency filtering. The issue is that the greedy phone companies don’t want to spend more money putting ground stations in, so they want to increase the power levels much higher. It is the high power output that is the issue, it exceeds the RADALT TSO filtering requirements.

Or is it an issue with greedy US aviation industry which prefers to stay in the '50s and refuse to upgrade anything to modern times??
Few examples:
Plane from 1960 is perfect, no need to upgrade.
ADS-B, who needs that, people have flown though Atlantic ocean without, too expensive.
And probably there is more.

While at the same time charging most expensive prices in the world.
Telecoms do upgrades almost yearly.

AndoAv8R wrote:

I wonder how much radiation in flight wifi or even a home wifi router creates compared to the radiation coming off a cell tower? and I know a lot of in home wifi routers are now using 5G as well (the new one i got when we switched to fiber optic a few weeks ago is 5G)

Different 5G, Wi-Fi 5G is 5GHz, 5G mobile is 5th generation.

miegapele wrote:

Or is it an issue with greedy US aviation industry which prefers to stay in the '50s and refuse to upgrade anything to modern times??

The TSOs are federal standards determined by organizations like the FAA and FCC, not by the aviation industry. The aviation industry is required to use TSO certified equipment.

Sparse tower spacing and therefore requiring high power to get overlapping coverage is industry driven, not by the equipment or standards or the government.

AndoAv8R wrote:

I wonder how much radiation in flight wifi or even a home wifi router creates compared to the radiation coming off a cell tower? and I know a lot of in home wifi routers are now using 5G as well (the new one i got when we switched to fiber optic a few weeks ago is 5G)

5G base stations can use antenna arrays that focus the power in specific directions, which enables a maximum EIRP of around 80 dBm or more (per the RTCA report), or around 100 kW. Wifi is limited to 36 dBm, or 4 W. So there's a significant difference in the power output.

In addition, wifi operates in either the 2.4 GHz (2412-2472 MHz) or the 5 GHz band (5150-5350 and 5470-5725 MHz), both of which are far away from the frequencies that the altimeters use and are sensitive to.

kalvado wrote:

Once you're a bit further away - a step or two in case of 5g - you are pretty much safe. Regulations add another factor of a lot for safety.

I'm not sure if a step is enough but 10-15 m should be more than sufficient to avoid any health effects from even the strongest 5G signal. The received power at that distance is comparable to the power output of a regular phone or a wifi transmitter.

Will it mean no more airplane mode on phones? Passengers would have to turn off all mobile phones?

Ziyulu wrote:

Will it mean no more airplane mode on phones? Passengers would have to turn off all mobile phones?

Unlikely. Airplane mode already turns off the transmitter on the phone. The issue is more with interference from the 5G cell towers.

Yesterday during a low visibility approach in CDG, the captain asked us passengers to turn off all electronic devices (not even on airplane mode). It was an EasyJet flight on a young A321neo. I noticed some concern among my fellow passengers before this new instruction.

I told my worried neighbour that it was probably due to this new 5G frequency issue but I am not sure if it was really related. (Not U.S. Airspace)

LaunchDetected wrote:

Yesterday during a low visibility approach in CDG, the captain asked us passengers to turn off all electronic devices (not even on airplane mode). It was an EasyJet flight on a young A321neo. I noticed some concern among my fellow passengers before this new instruction.

I told my worried neighbour that it was probably due to this new 5G frequency issue but I am not sure if it was really related. (Not U.S. Airspace)

That has been standard on any LVO approach well before 5G.

zeke wrote:

LaunchDetected wrote:

Yesterday during a low visibility approach in CDG, the captain asked us passengers to turn off all electronic devices (not even on airplane mode). It was an EasyJet flight on a young A321neo. I noticed some concern among my fellow passengers before this new instruction.

I told my worried neighbour that it was probably due to this new 5G frequency issue but I am not sure if it was really related. (Not U.S. Airspace)

That has been standard on any LVO approach well before 5G.

Thank you for your answer, definitely never happened to me before yesterday. It makes sense now.

kitplane01 wrote:

Pretend I'm a pilot. Use technical words. Which operations are to be prohibited?

This document (https://www.faa.gov/sites/faa.gov/files/2021-12/FRC_Document_AD-2021-01169-T-D.pdf, page 15) seems to say every ILS landing at any affected airport, but that cannot be right.

For my airline, a worldwide major cargo carrier, we won't be able to dispatch to nor shoot an approach to a CAT II, III, RNP-AR, and HUD/EFVS approach as our ops procedures require a RADALT for those approaches. A good old hand-flown CAT I ILS, we'll still be able to do as we don't fly those off of the radar altimeter. We dont fly SA CAT I.

The issue is which approaches at which specific airports will be affected? Will the ILS 5 CAT II at KFWA be ok in the post-5G world, how about the ILS 27R CAT III at KLAX? No-one can authoritatively answer that question yet until the NOTAMs start to get published...

Interesting that the US decided to restrict commercial airliners around 5G signals, whereas Canada decided to restrict 5G signals near busy airports.

https://www.thestar.com/amp/business/20 ... rvice.html

zeke wrote:

I have landed on that runway many times, I actually prefer it in strong crosswinds to the longer one.

Totally unrelated to the discussion at hand, but how come? Is it wider than the longer runway?

Thenoflyzone wrote:

Interesting that the US decided to restrict commercial airliners around 5G signals, whereas Canada decided to restrict 5G signals near busy airports.

https://www.thestar.com/amp/business/20 ... rvice.html

Which is what every other country in the world did too.

The problem is that telecoms have much deeper pockets than the airlines in the US. Airlines not being able to land a few days out of the year vs billions telecoms are giving the government for use of 5G networks and you start to see the problem.

a320fan wrote:

Is the 5G they’re rolling out in the US different to what’s been operating in many other locations globally with no noise been made about any issues? I believe here in Australia 5G is already quite widespread.

Hya.

Thanks for pointing it out.

Same here: in the UK, we do not seem to have neither the same concerns neither Boeing and Airbus pitching for a delay on 5G implementation or sharing concerns on the impact on their aircraft's operations. Most of London (and LHR areas, for that matter) are 5G hotspots.

Is the UK 5G Implementation any different to what Verizon, for example, plans in the US? Why don't we have the same issues in the UK also?

Jomar777 wrote:

Is the UK 5G Implementation any different to what Verizon, for example, plans in the US? Why don't we have the same issues in the UK also?

I think the UK stop their mid frequency 5G allocation at 3.8GHz, with aircraft radar altimeters operating in the 4.2–4.4 GHz range. US frequency allocation if different to the UK, it goes higher closer to the radalt frequency.

smartplane wrote:

LAXLHR wrote:

720B wrote:

FAA to prohibit many flight operations due to risk of ‘5G’ wireless interference


https://travelandaviation.com/faa-to-pr ... ence-news/

The moves come as US wireless communications companies prepare on 5 January to start, in 46 markets, transmitting in the 3700-3800 MHz range – the “C-Band”. That range is too close to the 4200-4400 MHz range used by aircraft radio altimeters, the FAA says.

As I read all of this, and some links, all I can think about is if it can interfere with aircraft, what about our bodies? We will have the answers fairly soon for sure.

I find it amazing that the FAA and FCC did not discuss this...but then again, why would they?! haha.

You raise an excellent point.

We have spectacular views, but unfortunately live near a cluster of three cell phone towers.

The National Radiation Laboratory used to test at selected properties in the area, including our own, which over the years showed a steady increase in both peak and average exposures.

5G is expected to be a step up. Unfortunately the mobile companies have refused to continue funding the tests.

"Radiation" from an antenna transmitting radio waves is not the same kind of "radiation" that comes from a nuclear reaction. 5G doesn't step anything up except that there are some higher frequency bands used. Even if you are really close to a tower, the power received from the antenna is measured in femtowatts.

zeke wrote:

Jomar777 wrote:

Is the UK 5G Implementation any different to what Verizon, for example, plans in the US? Why don't we have the same issues in the UK also?

I think the UK stop their mid frequency 5G allocation at 3.8GHz, with aircraft radar altimeters operating in the 4.2–4.4 GHz range. US frequency allocation if different to the UK, it goes higher closer to the radalt frequency.

Yes. This issue is mostly located in US. Other parts of the world are not allowing 5G Band C deployment near airports.

Is this really a more serious issue than cell phones? I’ve never seen anyone claim that airplane mode is a strict necessity with a straight face other than FA reading off a card while other FAs are on their phones….

There is no issue for someone using the 5G cellphones inside the airplane. The issue is the airplane flying over 5G towers. Some airports have cellphone towers very close to runways final approach paths. This could be an issue to some radar altimeters if the tower is transmitting the 5G C-Band and the aircraft fly over it.

LaunchDetected wrote:

Yesterday during a low visibility approach in CDG, the captain asked us passengers to turn off all electronic devices (not even on airplane mode). It was an EasyJet flight on a young A321neo. I noticed some concern among my fellow passengers before this new instruction.

I told my worried neighbour that it was probably due to this new 5G frequency issue but I am not sure if it was really related. (Not U.S. Airspace)

It wasn't due to 5G. It is a standard request from flight crews doing low visibility HUD and autoland approaches. The threat is miniscule, but enough that it absolutely makes sense to comply.

[url][/url]

kalvado wrote:

Jungleneer wrote:

There is no issue for someone using the 5G cellphones inside the airplane. The issue is the airplane flying over 5G towers. Some airports have cellphone towers very close to runways final approach paths. This could be an issue to some radar altimeters if the tower is transmitting the 5G C-Band and the aircraft fly over it.

Uplink and downlink seem to use same band, so your phone sending 5G data certainly can screw up avionics same way as base station can.
Now I don't know enough about 5g to say if there will be any transmission at those frequencies if there is no incoming messages to tell the phone that those are available.

RTCA performed some tests and concluded that 5G usage inside planes pose no harm. Maybe it is due to low transmit power of mobile devices.
The issue was really fly over cell phone towers. Which transmit with much higher power.

Jungleneer wrote:

There is no issue for someone using the 5G cellphones inside the airplane. The issue is the airplane flying over 5G towers. Some airports have cellphone towers very close to runways final approach paths. This could be an issue to some radar altimeters if the tower is transmitting the 5G C-Band and the aircraft fly over it.

Serious question, what is 'close'?

Here are the facts and figures presented by the Mobile industry. I am not endorsing anything in this report ( or any other) I am just posting the link and you can decide. I honestly do not have an idea about who is correct. However I think Safety should be the path forward until the effects (or Non effects) can be proven.

https://www.5gandaviation.com/?gclid=Cj ... t8QAvD_BwE

People are saying that we shouldn't reinvent the wheel, but what if the plane is hovering on a cushion of air or levitating on magnets? I believe magnets are already used in some military grade plane take-off configurations!

kalvado wrote:

zeke wrote:

GalaxyFlyer wrote:

Or click off the autothrottles and go manual….

How are they to know ?

The RTCA have found that in their testing that 5G drowns out RADALT at 270 ft, and is a danger at around 600 ft and 1000 ft on an ORD 27L approach see Figure 10-33 in this report https://www.rtca.org/wp-content/uploads ... hanges.pdf

A summary here
https://www.rtca.org/wp-content/uploads ... meters.pdf

Besides it also impacts other systems like GPWS, wind shear, and TCAS that also have inputs from RADALT.

The other side of the coin is that those systems fail because they are not designed to more or less modern standards.
Same type of conflict, except planes are on the other side of the issue:

Which airport is that?

Tokyo Narita (NRT)

dispatchguy wrote:

For my airline, a worldwide major cargo carrier, we won't be able to dispatch to nor shoot an approach to a CAT II, III, RNP-AR, and HUD/EFVS approach as our ops procedures require a RADALT for those approaches. A good old hand-flown CAT I ILS, we'll still be able to do as we don't fly those off of the radar altimeter. We dont fly SA CAT I.

The issue is which approaches at which specific airports will be affected? Will the ILS 5 CAT II at KFWA be ok in the post-5G world, how about the ILS 27R CAT III at KLAX? No-one can authoritatively answer that question yet until the NOTAMs start to get published...

All of this just in time for winter.

zeke wrote:

Tokyo Narita (NRT)

Thanks!

ikramerica wrote:

But we gotta what 8K HDR videos on our phones, why not.

Stupid question, but are you being facetious? If not, that's amazing. I remember it like it was only yesterday when I got my first phone capable of recording in 2160p @30FPS and being amazed beyond belief.

EDIT: You're not - holy crap, that's incredible, 8k video recording on phones already is here? - 0 ____ 0 -

frmrCapCadet wrote:

Jungleneer wrote:

There is no issue for someone using the 5G cellphones inside the airplane. The issue is the airplane flying over 5G towers. Some airports have cellphone towers very close to runways final approach paths. This could be an issue to some radar altimeters if the tower is transmitting the 5G C-Band and the aircraft fly over it.

Serious question, what is 'close'?

Effects on the radar altimeter readings starts to be noticed until altitudes 500 ft above the transmitter. Above this, the effects are minimal.

FCC commissioner tells DOT to go pound sand.

Separately, FCCstates nearly 40 nations have turned on 5G using C-band spectrum without endangering aviation.





https://pbs.twimg.com/media/FIDOqbvX0AI ... name=large
https://pbs.twimg.com/media/FIDOqbuXEAE ... name=large
https://pbs.twimg.com/media/FIDOqbsWUAU ... name=large

Jungleneer wrote:

zeke wrote:

Jomar777 wrote:

Is the UK 5G Implementation any different to what Verizon, for example, plans in the US? Why don't we have the same issues in the UK also?

I think the UK stop their mid frequency 5G allocation at 3.8GHz, with aircraft radar altimeters operating in the 4.2–4.4 GHz range. US frequency allocation if different to the UK, it goes higher closer to the radalt frequency.

Yes. This issue is mostly located in US. Other parts of the world are not allowing 5G Band C deployment near airports.

Hong Kong disallowed 5G n78 frequency band deployment near C-Band Satellite Stations, but didn't exclude their deployment near Hong Kong Airport.

Do not make this thread political. Political comments are restricted to the Non Aviation Forum.

✈️ atcsundevil

LAXintl wrote:

FCC commissioner tells DOT to go pound sand.

Separately, FCCstates nearly 40 nations have turned on 5G using C-band spectrum without endangering aviation.





https://pbs.twimg.com/media/FIDOqbvX0AI ... name=large
https://pbs.twimg.com/media/FIDOqbuXEAE ... name=large
https://pbs.twimg.com/media/FIDOqbsWUAU ... name=large

It sounds a bit like the FCC is in the hand of the large telecommunication providers in the US. More like a lobby association, than an organisation interested in the safety of the people.

I understand that they make billions from licensing these frequencies, but they are not a for-profit-organisation and when their main argument is "companies spend billions on this technology and now we can't say no anymore" (to sum it up), then this is not very reassuring, it doesnt't seem like the FCC is doing their job. As FAA I would not accept that and demand large scale tests over 5G antennas.

CARST wrote:

LAXintl wrote:

FCC commissioner tells DOT to go pound sand.

Separately, FCCstates nearly 40 nations have turned on 5G using C-band spectrum without endangering aviation.





https://pbs.twimg.com/media/FIDOqbvX0AI ... name=large
https://pbs.twimg.com/media/FIDOqbuXEAE ... name=large
https://pbs.twimg.com/media/FIDOqbsWUAU ... name=large

It sounds a bit like the FCC is in the hand of the large telecommunication providers in the US. More like a lobby association, than an organisation interested in the safety of the people.

I understand that they make billions from licensing these frequencies, but they are not a for-profit-organisation and when their main argument is "companies spend billions on this technology and now we can't say no anymore" (to sum it up), then this is not very reassuring, it doesnt't seem like the FCC is doing their job. As FAA I would not accept that and demand large scale tests over 5G antennas.

That letter is painful to read.

It says that 5G is being delivered in a safe and lawful way. It is written like a legal argument. It says that C-BAND is live in 40 countries including ones that have authorized it at higher power than the FCC so therefore the FCC analysis that it is safe is valid. What is missing from that argument is no countries are referenced (or known) to have actually implemented 5G at the power levels that Verizon and AT&T are planning on doing January 5. That kind of sounds like a logical fallacy (propaganda) and then just throws darts and cheap shots at anyone who disagrees with the FCC.

The letter would have a lot more credibility if someone had actually done an analysis of altimeters near these towers that proves that there isn’t interference and that airplanes will be safe. Unfortunately it doesn’t sound like that happened. I’m guessing because such a study may not have the results that the FCC desires. I think large scale tests over 5G antennas would be prudent.

Weatherwatcher1 wrote:

It says that 5G is being delivered in a safe and lawful way. It is written like a legal argument. It says that C-BAND is live in 40 countries including ones that have authorized it at higher power than the FCC so therefore the FCC analysis that it is safe is valid. What is missing from that argument is no countries are referenced (or known) to have actually implemented 5G at the power levels that Verizon and AT&T are planning on doing January 5. That kind of sounds like a logical fallacy (propaganda) and then just throws darts and cheap shots at anyone who disagrees with the FCC.

The letter would have a lot more credibility if someone had actually done an analysis of altimeters near these towers that proves that there isn’t interference and that airplanes will be safe. Unfortunately it doesn’t sound like that happened. I’m guessing because such a study may not have the results that the FCC desires. I think large scale tests over 5G antennas would be prudent.

But that what it is. 5G is delivered in fine and lawful manner, using assigned frequencies. The problem is that radar altimeters supposedly are heavily overstepping their assigned frequency of 4200-4400mhz. If they were not doing that, there would be no problem, but that probably require updating some equipment from the '50s or so and FAAand airlines do not want that.
Or maybe it's some bigger game being played somewhere, because these auctions were planned when, in 2018? And FAA only woke up now, week before deployment? That is odd.

Weatherwatcher1 wrote:

CARST wrote:

LAXintl wrote:

FCC commissioner tells DOT to go pound sand.

Separately, FCCstates nearly 40 nations have turned on 5G using C-band spectrum without endangering aviation.





https://pbs.twimg.com/media/FIDOqbvX0AI ... name=large
https://pbs.twimg.com/media/FIDOqbuXEAE ... name=large
https://pbs.twimg.com/media/FIDOqbsWUAU ... name=large

It sounds a bit like the FCC is in the hand of the large telecommunication providers in the US. More like a lobby association, than an organisation interested in the safety of the people.

I understand that they make billions from licensing these frequencies, but they are not a for-profit-organisation and when their main argument is "companies spend billions on this technology and now we can't say no anymore" (to sum it up), then this is not very reassuring, it doesnt't seem like the FCC is doing their job. As FAA I would not accept that and demand large scale tests over 5G antennas.

That letter is painful to read.

It says that 5G is being delivered in a safe and lawful way. It is written like a legal argument. It says that C-BAND is live in 40 countries including ones that have authorized it at higher power than the FCC so therefore the FCC analysis that it is safe is valid. What is missing from that argument is no countries are referenced (or known) to have actually implemented 5G at the power levels that Verizon and AT&T are planning on doing January 5. That kind of sounds like a logical fallacy (propaganda) and then just throws darts and cheap shots at anyone who disagrees with the FCC.

The letter would have a lot more credibility if someone had actually done an analysis of altimeters near these towers that proves that there isn’t interference and that airplanes will be safe. Unfortunately it doesn’t sound like that happened. I’m guessing because such a study may not have the results that the FCC desires. I think large scale tests over 5G antennas would be prudent.

FCC's duty is to assign frequency bands to different operators for different purposes. As the letter mentioned, FCC have assigned more than requested guard band to separate telecommunication frequency from altimeters. If altimeters are still interfered then it mean they're using others' spectrum beyond the level of protection demanded by aviation industry.

An article on the subject from a think tank, likely funded by the telecom industry:

https://itif.org/publications/2021/11/09/c-band-spectrum-rollout-5g-and-aviation-altimeters

But the interesting takeaway:

In these cases, the fault is not with the new operator (assuming that they are staying in their band, which wireless operators do); it is with the adjacent user. As such, any responsibility for upgrading deficient older altimeters lies with their owners. The analogy would be to two houses in a county with a noise ordinance that has been set at a certain level assuming houses have modern double-pane windows. If one of the houses has older single-pane windows and they hear music from a next-door neighbor that is within the country noise ordinance, that’s their fault. The other neighbor still should have the right to play music in accordance with county law.

To continue this analogy, it is all too often the case that the neighbor with the broken windows complains to the government that their neighbors’ music is too loud—even though it meets the requisite decibel standards—so the house playing the music should have to pay for them to install new windows. In the case of C-band spectrum, the broken windows are the older altimeters that may pick up interference from 5G operators in the adjacent band—and like neighbors with a single-pane window. In this case, it’s the responsibility of the owners of older, less accurate altimeters to fix them so that they operate in the band they were licensed for.

It seems the only 2 viable solutions to ensure safety is to:
1. run numerous test approaches above these transmitters to actually determine if a problem does exist (w/ various eqp types); up till this point it sounds like the RTCA study is mostly theoretical?
2. create transmitter-free zones beneath instrument approach path corridors (1nm wide x 5nm etc..) e.g., what Canada is doing, to avoid the potential risks of bogus RA' readouts.

I guess right now it's just a good old standoff between the FAA and FCC w/ the airlines as piggy in the middle.

To me the FAA was asleep at the wheel again.

This train left the station many years ago, and instead of making sure avionics manufacturers and operators have compliant equipment, we have this 11th standoff with industry panicking.
The time for debate was years ago when the FAA and industry had their opportunity to weigh in, but instead seems everyone sat on their hands until late 2021.

Weatherwatcher1 wrote:

It says that C-BAND is live in 40 countries including ones that have authorized it at higher power than the FCC so therefore the FCC analysis that it is safe is valid. What is missing from that argument is no countries are referenced (or known) to have actually implemented 5G at the power levels that Verizon and AT&T are planning on doing January 5.

What is also missing is that no other country is operating that close to the radar altimeter frequency with their 5G network, most that I have noticed are actually in S band (2 – 4 GHz) not C band (4 – 8 GHz) . FCC is calling it C band, the frequencies auctioned off between 3.7-4.2 GHz are in the S band and C band.

The letter is disingenuous.

miegapele wrote:

The problem is that radar altimeters supposedly are heavily overstepping their assigned frequency of 4200-4400mhz. If they were not doing that, there would be no problem, but that probably require updating some equipment from the '50s or so and FAAand airlines do not want that.

I don’t think that is the case. The design rules/specifications related to rad alts comes from the feds, those specifications also include things like the filtering requirements, they have been in place for probably 50 years. Rad alts are fairly low power and need to perform over changing terrain of varying reflectivity, they return an average height over an area rather than a precise height over a point. That height is continuously fed into the flight control computers on approach. An incorrect rad alt reading can inhibit safety features like weather radar predictive windshear, EICAS/ECAM cautions/warnings, GPWS, TCAS, and autothrust all of which use rad alt output.

n797mx wrote:

Thenoflyzone wrote:

Interesting that the US decided to restrict commercial airliners around 5G signals, whereas Canada decided to restrict 5G signals near busy airports.

https://www.thestar.com/amp/business/20 ... rvice.html

Which is what every other country in the world did too.

The problem is that telecoms have much deeper pockets than the airlines in the US. Airlines not being able to land a few days out of the year vs billions telecoms are giving the government for use of 5G networks and you start to see the problem.

I agree it would have been far better for FAA and FCC to coordinate in advance, but when push comes to shove it is the aircraft receiver's inability to reject out of band signals that is the core issue, so it is on the FCC and the aviation industry to have been proactive as the 5G standards were well known in advance.

In a way this can become an interesting exercise in how the aviation industry can respond to an urgent need to adapt to changing circumstances. The ball is now in their court.

I also agree that the telcoms have a lot of money thus clout, and the case for 5G is being vastly overstated, but that's a topic for another day.

UPlog wrote:

To me the FAA was asleep at the wheel again.

This train left the station many years ago, and instead of making sure avionics manufacturers and operators have compliant equipment, we have this 11th standoff with industry panicking.
The time for debate was years ago when the FAA and industry had their opportunity to weigh in, but instead seems everyone sat on their hands until late 2021.

zeke wrote:

What is also missing is that no other country is operating that close to the radar altimeter frequency with their 5G network, most that I have noticed are actually in S band (2 – 4 GHz) not C band (4 – 8 GHz) . FCC is calling it C band, the frequencies auctioned off between 3.7-4.2 GHz are in the S band and C band.

That is false, states is also using <4Mhz frequencies, see https://www.fcc.gov/auction/107/factsheet
Russia and china is planning to use something above 4Ghz, I do not know about anybody else in that range. Problem for FAA seems to be that even 200Mhz of guard is not enough for them, which looks way to much for modern times. However this is radar and not data transmission, so maybe it has some reasoning. Except that this auction was announced few years back, and FAA only now decided to wake up.

miegapele wrote:

zeke wrote:

What is also missing is that no other country is operating that close to the radar altimeter frequency with their 5G network, most that I have noticed are actually in S band (2 – 4 GHz) not C band (4 – 8 GHz) . FCC is calling it C band, the frequencies auctioned off between 3.7-4.2 GHz are in the S band and C band.

That is false, states is also using <4Mhz frequencies, see https://www.fcc.gov/auction/107/factsheet
Russia and china is planning to use something above 4Ghz, I do not know about anybody else in that range. Problem for FAA seems to be that even 200Mhz of guard is not enough for them, which looks way to much for modern times. However this is radar and not data transmission, so maybe it has some reasoning. Except that this auction was announced few years back, and FAA only now decided to wake up.

The Intensity is increasing, but the FAA isn’t just waking up.

Article from 2020 https://www.popularmechanics.com/techno ... -concerns/

“Once 5G telecommunications are introduced in the 3.7-3.98 portion of the band, there is a ‘major risk’ that those systems will create ‘harmful interference’ to radar altimeters, according to an October study from the RTCA, a trade organization that works with the FAA to develop safety standards.”

In its defense, the FCC says the buffer of bandwidth is large enough that it doesn’t believe altimeter interference is even a real possibility.

But the concerns are being pushed by a telecommunications lobbying group, and the FCC itself is led by partisan former Verizon lawyer Ajit Pai, who also opposes net neutrality.

Oh, boy. https://www.wsj.com/articles/at-t-veriz ... _lead_pos2

I think they should put Stankey and Vestberg on multiple CATIIIB Autoland flights and see how they feel about their systems then. https://www.youtube.com/watch?v=C84FEFjBj3o https://www.youtube.com/watch?v=u62Kn0DvRU8

You can see how important the radio altimeter is to all this in this video by Pilot_Obet in the simulator. Explains the whole procedure nicely (Training Captain for CX). https://www.youtube.com/watch?v=OMPms3XPaFI&t