This whole issues has so many layers to it, but a big part of the problem is the FCC selling so much spectrum. They could have reserved a little more frequency. Block out 3.96 to 4 gigahertz, giving a bigger buffer. I think they cared more about the money though, selling this frequency. Looking up on Google, they did do studies before and were told there may be interference, but it went to deaf ears.

What the US needs to do is copy what France is doing. Have a larger buffer zone around airports, reduce transmission power, and angle the receivers downward. It seems to work. I'm sorry, but "media consumption" shouldn't be a priority. You can still make calls, send texts, use IM, and all your apps now as is, just maybe not as fast as if 5G had full power. Just do this around the airports and we can reach a compromise. The telecoms don't need every single square foot of 5G top speed, and neither do people, since it's working fine as is now. The government may have to pay back the telecoms some of the billions to restrict use around airports. I'm not saying take the whole frequency away, only around airports, or reduce the power and do some modifications.

What baffles me is this is an airline enthusiast website, but so many people are defending the telecoms.

USAirKid wrote:

The more and more I think about it, this should be a faulty product claim from the airplane owners to Boeing, Airbus, Honeywell, and whoever else.

A vast majority of the affected airline equipment was placed into service within the past 20 years. At that time it was foreseeable that wireless communication was going to rise. At the same time it was known that the filters on the radalts were not filtering out frequencies that were not assigned to that use.

The government and the telecoms should not pay for this. The manufacturers should have delivered equipment that met radio transmission standards in 1996, not 1966.

It did meet standards in 1996 or it would not have been sold.

If the standards were out of date, that's on FAA and FCC.

travaz wrote:

Was there ever any claims of interference from C band Satellite? That was 3.7 to 4.2 which is pretty close to RADALT.

I suppose there was a chance of such interference near the earth stations that transmit to satellites, but they use dish antennas that are pointed at the sky and are very directional and there aren't very many of them. I presume their location was chosen to not be in the landing pattern of major airports.

It's really a lot different than cell towers sprinkled across the landscape transmitting 1.5 kilowatts radiating in every direction.

Jshank83 wrote:

Seems like the easy fix from the start would have been to say it won’t be allowed within X miles from an airport. Or at least, it won’t be allowed within X miles until we know what it does.

As per #268 above, FAA was doing just that. They were asking FCC to hold off till the issues were understood, but FCC just went ahead anyway.

DXTraveler wrote:

Somewhere in the bowels of these government agencies I can hear the engineers saying we told you so. No surprise that in our government the lobbyists and political appointees win the day. This is the result.

You get the government you elect. One set of political beliefs portray government as nothing but an obstruction, yet this case shows where we'd all be a lot better off if the government had enough power to steer events. Given they don't, we end up with open corporate warfare and the side with the most money wins.

kalvado wrote:

On a serious note, though, scope if work is much smaller. They need add-on filters for existing units, and those can be small ones, size of a matchbox or so.
And if telecom industry can be brought on board, it will be about qualified people who are doing RF for a living, not Boeing or Honeywell, working on the project. 12 months would be about right.
At the very least, there would be a solid understand of a problem, and a reasonable position for limitations required to keep things moving (and flying). Much more solid position for talks.

Then, in 20 years from now a bunch of Internet know-it-alls will be writing about that one year rush job not taking into account the last twenty years of advancement in wireless technology.

c933103 wrote:

Also, the report also mentioned that,

348. By licensing only up to 3.98 GHz as flexible-use spectrum, we are providing a 220-
megahertz guard band between new services in the lower C-band and radio altimeters and Wireless
Avionics Intra-Communications services operating in the 4.2-4.4 GHz band. This is double the guard
band supported in initial comments by Boeing and ASRC.

So the guard band requested by Boeing was less than half of 220MHz. In other words Boeing have been okay with 5G up to about 4.1 GHz. Why would mobile operators think 3.x GHz frequency will have problem when Boeing say up to 4.1 GHz is okay?

We don't know that this was Boeing's *only* recommendation. They may have been OK with a smaller guard band if it came with other stipulations such as no cell towers within N miles of the airport, limitations on antenna directivity, limits on transmitter power, etc.

32andBelow wrote:

If I was the telcos I’d be looking for damages if they can’t operate their approved spectrum

And if you were JL, EK, etc you can already begin to sue the telcos for lost revenue.

danman132x wrote:

What the US needs to do is copy what France is doing. Have a larger buffer zone around airports, reduce transmission power, and angle the receivers downward.

This isn't France. We don't do compromise in this country any more. We follow the golden rule, he with the gold rules.

Both sides have armies of paid help, none of which can go back and tell their employers that they "caved in" if they want to keep their future prospects intact.

danman132x wrote:

What baffles me is this is an airline enthusiast website, but so many people are defending the telecoms.

Which suggests to me that the general public is even more pro-telcom and the airline side is playing a losing hand.

It isn't lost on me that it is international airlines that are the ones to say "bleep them and their nonsense, we're staying away" just like it was foreign regulators who said "bleep the FAA and their nonsense, we're grounding the MAX".

We really could use some adults in the room, but we live in the era where social media mobs rule and corporations are people too.

chrisnh wrote:

FAA exempted Boston because the airport wasn’t too close to any towers. Yet Emirates pulls its flight. I’m not saying that 5G isn’t a causal factor here, but nor do I think it’s the sole reason EK is doing this.

Yet the NOTAM is still active for BOS.

!BOS 01/437 BOS AD AP RDO ALTIMETER UNREL. AUTOLAND, HUD TO TOUCHDOWN, ENHANCED FLT VISION SYSTEMS TO TOUCHDOWN, HEL OPS REQUIRING RDO ALTIMETER DATA TO INCLUDE HOVER AUTOPILOT MODES AND CAT A/B/PERFORMANCE CLASS TKOF AND LDG NOT AUTHORIZED EXC FOR ACFT USING APPROVED ALTERNATIVE METHODS OF COMPLIANCE DUE TO 5G C-BAND INTERFERENCE PLUS SEE AIRWORTHINESS DIRECTIVES 2021-23-12, 2021-23-13 2201190501-2401190501

Don't believe everything you read in the news. Operators must comply with the Airworthiness Directive(s) and NOTAM(s).

EK211 DXB-IAH (77L, return is EK212) was indeed canceled today, though I see on FlightAware that EK has a 380 due to leave DXB at 10:05 local time on the 20th (15 hours from now). If that's accurate, that suggests that EK is subbing a 380 to accommodate those who were supposed to be on today's canceled 77L flight.

danman132x wrote:

My opinion is that the cell companies need to drop this frequency. Do we Really need this 5G spectrum. Our cell phones work fine as is. 5G works fine how it is now, we can make calls just fine and have been for years, why now? So we can browse Facebook faster or watch YouTube videos on the go in high speed? It's ridiculous honestly. Wait until the first plane crashes because this interference, or flights are constantly disrupted. Better hope it's not rainy or cloudy the day you want to fly. Going to be a lot of canceled flights. I would expect no less from the American government. All about the money instead of safety.

And what happens to the money that the cell companies paid for this frequency?

Why can’t the airlines just defer cat 3 approaches to these airports. Or is there something else that’s affected? Plenty of planes fly commercially without auto land

Revelation wrote:

kalvado wrote:

On a serious note, though, scope if work is much smaller. They need add-on filters for existing units, and those can be small ones, size of a matchbox or so.
And if telecom industry can be brought on board, it will be about qualified people who are doing RF for a living, not Boeing or Honeywell, working on the project. 12 months would be about right.
At the very least, there would be a solid understand of a problem, and a reasonable position for limitations required to keep things moving (and flying). Much more solid position for talks.

Then, in 20 years from now a bunch of Internet know-it-alls will be writing about that one year rush job not taking into account the last twenty years of advancement in wireless technology.

Of course, it may be a temporary fix. But one thing at a time.
Anyway, I am sure US skygods should be able to land with such a minor malfunction as a single non-functional piece of instrumentation.

MIflyer12 wrote:

ItnStln wrote:

And what happens to the money that the cell companies paid for this frequency?

It's not just what telcos paid in spectrum fees - it's also all the equipment they bought and installed to use that spectrum.

It would be much, much cheaper just to replace a few thousand impacted altimeters.

I'm not disagreeing with you, at all! At this point it will be who has the largest lobbyist groups, the airlines or the telecommunications industry. The cell companies purchased the frequency to utilize for their 5G networks, and if there was a known issue it should have been disclosed to them.

32andBelow wrote:

Why can’t the airlines just defer cat 3 approaches to these airports. Or is there something else that’s affected? Plenty of planes fly commercially without auto land

Additional integrated systems on some aircraft also depend on radio altimeter inputs. This could impact ground spoilers, thrust reversers, auto brakes, etc.

From Rev.. "You get the government you elect. One set of political beliefs portray government as nothing but an obstruction, yet this case shows where we'd all be a lot better off if the government had enough power to steer events. Given they don't, we end up with open corporate warfare and the side with the most money wins."

Anybody have the specifics of the authorization to sell the bandwidth RFs in question. It is ultimately Congress and the President who are responsible? Was it partisan, or as I suspect quietly settled in committee rooms, and packaged with other legislation which made the President's signature almost irrelevant.

32andBelow wrote:

Why can’t the airlines just defer cat 3 approaches to these airports. Or is there something else that’s affected? Plenty of planes fly commercially without auto land

A radio altimeter feeds its data to multiple systems. Mainly the EGPWS, the tail strike avoidance system, autothrust, autopilot, etc.

And many systems are quite important if something else goes wrong.

Eikie wrote:

32andBelow wrote:

Why can’t the airlines just defer cat 3 approaches to these airports. Or is there something else that’s affected? Plenty of planes fly commercially without auto land

A radio altimeter feeds its data to multiple systems. Mainly the EGPWS, the tail strike avoidance system, autothrust, autopilot, etc.

And many systems are quite important if something else goes wrong.

Oh ok. There’s not backup standard altimeter that the pilots can set manually?

MIflyer12 wrote:

ItnStln wrote:

And what happens to the money that the cell companies paid for this frequency?

It's not just what telcos paid in spectrum fees - it's also all the equipment they bought and installed to use that spectrum.

It would be much, much cheaper just to replace a few thousand impacted altimeters.

How do you figure it will be cheaper?
If I go by the requirements to get the MAX software and hardware fixes installed, tested then approved by the FAA it will not be cheap and not done quickly. The repairs to MCAS once the grounding of MAX was accomplished was done pretty quickly, getting the FAA and EASA to approve and certify the changes took the majority of the time.
Now imagine new radar altimeters being designed, tested then deployed to thousands of planes, most likely all having to be certified by their host countries.

32andBelow wrote:

Why can’t the airlines just defer cat 3 approaches to these airports. Or is there something else that’s affected? Plenty of planes fly commercially without auto land

It´s far more complicated than that. Not only low-vis, but flying over a 5G tower may (and I emphasize may) have the Radio Altitude drop to say 20 ft where some aircraft will think they are landing and affect systems accordingly. There are several systems that use Rad alt as input.

kalvado wrote:

Of course, it may be a temporary fix. But one thing at a time.
Anyway, I am sure US skygods should be able to land with such a minor malfunction as a single non-functional piece of instrumentation.

Since the flights canceled so far are by foreign airlines whose pilots are trained to let the computers do the bulk of the work for safety reasons, not sure where the skygods fit in.

par13del wrote:

MIflyer12 wrote:

ItnStln wrote:

And what happens to the money that the cell companies paid for this frequency?

It's not just what telcos paid in spectrum fees - it's also all the equipment they bought and installed to use that spectrum.

It would be much, much cheaper just to replace a few thousand impacted altimeters.

How do you figure it will be cheaper?
If I go by the requirements to get the MAX software and hardware fixes installed, tested then approved by the FAA it will not be cheap and not done quickly. The repairs to MCAS once the grounding of MAX was accomplished was done pretty quickly, getting the FAA and EASA to approve and certify the changes took the majority of the time.
Now imagine new radar altimeters being designed, tested then deployed to thousands of planes, most likely all having to be certified by their host countries.

So the government is going to have to pay to reimburse for all the 5G tower and spectrum costs if this is the case

32andBelow wrote:

par13del wrote:

MIflyer12 wrote:

It's not just what telcos paid in spectrum fees - it's also all the equipment they bought and installed to use that spectrum.

It would be much, much cheaper just to replace a few thousand impacted altimeters.

How do you figure it will be cheaper?
If I go by the requirements to get the MAX software and hardware fixes installed, tested then approved by the FAA it will not be cheap and not done quickly. The repairs to MCAS once the grounding of MAX was accomplished was done pretty quickly, getting the FAA and EASA to approve and certify the changes took the majority of the time.
Now imagine new radar altimeters being designed, tested then deployed to thousands of planes, most likely all having to be certified by their host countries.

So the government is going to have to pay to reimburse for all the 5G tower and spectrum costs if this is the case

If this happens it needs to be at cost to the cell companies, and not at a profit. If there was a known issue, or a potential issue, it should have been disclosed to the carriers who made it known that the frequency was being purchased for their 5G networks.

32andBelow wrote:

Why can’t the airlines just defer cat 3 approaches to these airports. Or is there something else that’s affected? Plenty of planes fly commercially without auto land

Presumably they don't want to deal with liability issues. If something goes wrong and they get sued, they face the claim of knowingly sending their aircraft into an environment where their pilots don't have all the tools they have trained with available to them, or some working incorrectly because all aspects of C-band interference have not yet been studied. Suppose years from now opposing counsel produces evidence that a certain C-band signal at a certain time causes a malfunction that no one currently knows about. They'd be facing some major liability issues.

kalvado wrote:

Of course, it may be a temporary fix. But one thing at a time.

Reminds me of a saying: there's nothing as permanent as a temporary tax!

kalvado wrote:

Anyway, I am sure US skygods should be able to land with such a minor malfunction as a single non-functional piece of instrumentation.

One data source would be malfunctioning, but it drives a lot of things (autoland, autothrottle, automatic thrust reverser deployment, etc).

par13del wrote:

Now imagine new radar altimeters being designed, tested then deployed to thousands of planes, most likely all having to be certified by their host countries.

Yes, and IIRC it's more than one vendor's model that needs to be addressed.

You gotta keep in mind that filters to block the 5G signal will also cause loss to the incoming RADALT echos which may need amplification.

Each model may need a unique solution.

Also there doesn't seem to be agreement on exactly what the new standard is, in terms of how much out of band rejection needs to be provided, etc.

frmrCapCadet wrote:

From Rev.. "You get the government you elect. One set of political beliefs portray government as nothing but an obstruction, yet this case shows where we'd all be a lot better off if the government had enough power to steer events. Given they don't, we end up with open corporate warfare and the side with the most money wins."

Anybody have the specifics of the authorization to sell the bandwidth RFs in question. It is ultimately Congress and the President who are responsible? Was it partisan, or as I suspect quietly settled in committee rooms, and packaged with other legislation which made the President's signature almost irrelevant.

In this case, we have bureaucratic government structure unable to operate. A real way forward is significant reform of government agencies - Cxx'ex, Fxx'es, Dxx'es. And that is virtually impossible for elected officials.
One good thing one of previous presidents with a very low approval rating was trying to do is to put some common sense into EPA. Outcry was tremendous. Now there are tens of such agencies, each packed with seasoned bureaucrats with media connections.
Everyone praised a pilot appointed as FAA head. In every other industry, equipment operator is the lowest rank.
Can we imagine a nurse to be appointed as a head of FDA and a truck driver as a head of FHWA, for example?

Revelation wrote:

You get the government you elect. One set of political beliefs portray government as nothing but an obstruction, yet this case shows where we'd all be a lot better off if the government had enough power to steer events. Given they don't, we end up with open corporate warfare and the side with the most money wins.

My thought on this is the elections done every 2 and 4 years elects the leaders of the government, the folks who actually run the government / country are supposed to be the professionals who work in all the various government departments, the degrees that they require for the jobs they are supposed to do, do not allow them to be turned over on each election.
Other than the heads of the FAA, FCC etc who go through congressional hearings, the experts / engineers at both agencies have been in place longer than an election cycle. Yes the politicians worked to outsource a lot of those responsibilities to the private sector who have the resources, we saw how that worked with the FAA, question would be is / was the theory sound and the implementation botched?

32andBelow wrote:

Eikie wrote:

32andBelow wrote:

Why can’t the airlines just defer cat 3 approaches to these airports. Or is there something else that’s affected? Plenty of planes fly commercially without auto land

A radio altimeter feeds its data to multiple systems. Mainly the EGPWS, the tail strike avoidance system, autothrust, autopilot, etc.

And many systems are quite important if something else goes wrong.

Oh ok. There’s not backup standard altimeter that the pilots can set manually?

No, the idea is that it functions independently from any input.

For instance, a EGPWS system senses a too high closure rate towards terrain andd warms the crew they might be descending to fast (ie crashing).
Or the autothrust which needs to know when to reduce throttle when landing, which is a function of height above terrain (runway).

Would be "interesting" if you put in a wrong value and at a 1000 feest the system thinks it is almost at the runway.

Jon/TAC's reporting is to its usual high standards and not behind a paywall since it's a safety-related article:

https://theaircurrent.com/aviation-safe ... n-cluster/

Revelation wrote:

hivue wrote:

Revelation wrote:

The issue is the receiver that is a part of the airplane's radar altimeter (RADALT) does not reject the new 5G signals.

Or... the transmitter that is part of the telecomms' new 5G does not adequately control it's signals. Take your pick.

I think this is not the case, the 5G transmitter is transmitting in licensed bands at licensed power levels.

And radio altimeters don't? Are they rogue broadcasters?

What everyone should recognize is that what we have here is an enormous clash of cultures. The telecomms are used to spending gazillions on often over-hyped tech and turning that tech into profits as soon as possible. There is a relatively minimal downside and potentially a fantastic upside. Not a criticism. It you're a telecomm you're out of business in a heartbeat if you can't turn on a dime. Hans Vestgard was on CNBC this morning just bubbling over with enthusiasm about their completely and totally life-changing 5G rollout and not the least bit interested in discussing the inconvenient little10% of coverage affected by the current "crisis."

Aviation on the other hand has learned the hard way over many decades that if you trust tech without taking plenty of time and being very, very careful people die. On those occasions when they do try to turn new tech into profits as soon as possible they get MAXs with crazy MCASs and blood on their hands.

hivue wrote:

Revelation wrote:

hivue wrote:

Or... the transmitter that is part of the telecomms' new 5G does not adequately control it's signals. Take your pick.

I think this is not the case, the 5G transmitter is transmitting in licensed bands at licensed power levels.

And radio altimeters don't? Are they rogue broadcasters?

Both devices are transmitting legally. The issue is the RADALT is receiving signals outside of its allocated band.

Made the news in germany today as well. But stating, that it is here no problem, because of the usage of other frequencies than in the US. Not poining out witch other frequencies that are.
I want to note, that 5G, for me, is only just the next stunt for the companies to make money. Net coverage here is simply a joke. In the big city´s, ok, but on the countryside, if you are lucky you can barely talk, nice Data connections.. if you where lucky. Wide areas are just black holes, i experience it every day. I would not put these frequencies on a auction, that company, which takes care of that you have Netz at all, get´s the reward. But as always, the money..

hivue wrote:

Revelation wrote:

hivue wrote:

Or... the transmitter that is part of the telecomms' new 5G does not adequately control it's signals. Take your pick.

I think this is not the case, the 5G transmitter is transmitting in licensed bands at licensed power levels.

And radio altimeters don't? Are they rogue broadcasters?

What everyone should recognize is that what we have here is an enormous clash of cultures. The telecomms are used to spending gazillions on often over-hyped tech and turning that tech into profits as soon as possible. There is a relatively minimal downside and potentially a fantastic upside. Not a criticism. It you're a telecomm you're out of business in a heartbeat if you can't turn on a dime. Hans Vestgard was on CNBC this morning just bubbling over with enthusiasm about their completely and totally life-changing 5G rollout and not the least bit interested in discussing the inconvenient little10% of coverage affected by the current "crisis."

Aviation on the other hand has learned the hard way over many decades that if you trust tech without taking plenty of time and being very, very careful people die. On those occasions when they do try to turn new tech into profits as soon as possible they get MAXs with crazy MCASs and blood on their hands.

FCC certification requirement was, for ages, that device should not cause interference to others, but should be able to tolerate interference from other devices. Again, technically speaking, any transmission from the aircraft is FCC licensed. It is mostly formal thing, but yet. Looks like altimeters - relatively high power transmitters - evaded being certified. And - news flash! - they are uncertifyable.
So grounding - like it happened to MAX - is immediate withdraw of affected equipment. Oh, yes, it hurts.
But aviation industry should know the value of playing by the rules!

c933103 wrote:

casinterest wrote:

CBand for the Wireless companies is 3.7GHz to ~4Ghz
The radar altimeters on the planes are at 4.2 to 4.4 Ghz.

Don't these altimeters understand when the frequency coming back to them is not the one they are sending out?

Or is the Risk, that they can't control the frequency between the plane and the Ground and interference may occur?


Why not a sensible solution that the Cell companies around an airport use lower band frequencies (3.7-3.8)around the airport? The signal should stay out of the 4.2 to 4.4 range, even with 10-20% tolerance issues.

The auction was done in piece, every 20MHz. Like 3.7-2.72GHz is one segment, 3.72-3.74 is another, and all the way to 3.96-3.98, with the last slice of 3.98-4GHz being reserved exactly for the guarding purpose to separate from other bands, and then there are also another 200MHz between these and the Altimeter frequency.
Modern altimeters can distinguish these different frequencies, but some of the older ones cannot.
3.7-3.8GHz is still part of the FAA complain against the entire band, and limiting operation to this would nullifying two-third of the bidded mobile service capacity which operators spent tons of money to acquire, in addition to they might not be the same company who won the auction of higher parts of the band depending on location as different carriers bid different part of the spectrum and there are also some smaller companies who won a few pieces of these frequencies in some limited geographic area according to my understanding. Limiting operation to lower frequency band would mean all the investment and equipment paid by those who bidded in higher band will be completely wasted, for no good reason since even the closest band is still 220MHz away from the altimeter frequency, when those mobile communication each of them only use 20MHz

The issue of course is that no one vetted the old technology that claimed the 4.2 to 4.4 range. That is where the issue lies, but it is also least likely to be remedied anytime soon. The FCC sold the licenses, and the FAA failed to act expediently on an issue that has certified parts operating outside the licensed and advertised range.

Patience on both sides is going to run out and this whole thing is going to end up being a litigation s***storm, unless the federal government can find a permanent and mutually agreeable fix within the next few weeks. And their ability to do this is both legally and functionally questionable.

The two possible end states are either operators replace radio altimeter equipments, or wireless carriers accept permanent limitations on the 5G c-band. Both outcomes will result in significant costs to the other party, so the question becomes who will pay.

As usually, the biggest winners will be the lawyers.

kalvado wrote:

Revelation wrote:

kalvado wrote:

On a serious note, though, scope if work is much smaller. They need add-on filters for existing units, and those can be small ones, size of a matchbox or so.
And if telecom industry can be brought on board, it will be about qualified people who are doing RF for a living, not Boeing or Honeywell, working on the project. 12 months would be about right.
At the very least, there would be a solid understand of a problem, and a reasonable position for limitations required to keep things moving (and flying). Much more solid position for talks.

Then, in 20 years from now a bunch of Internet know-it-alls will be writing about that one year rush job not taking into account the last twenty years of advancement in wireless technology.

Anyway, I am sure US skygods should be able to land with such a minor malfunction as a single non-functional piece of instrumentation.

You should research the cause of many airplane crashes before making such a ridiculous statement. Most of the time they can, but that could be very catastrophic.

LAXdude1023 wrote:

kalvado wrote:

Revelation wrote:

Then, in 20 years from now a bunch of Internet know-it-alls will be writing about that one year rush job not taking into account the last twenty years of advancement in wireless technology.

Anyway, I am sure US skygods should be able to land with such a minor malfunction as a single non-functional piece of instrumentation.

You should research the cause of many airplane crashes before making such a ridiculous statement. Most of the time they can, but that could be very catastrophic.

This is in direct relation to "third world pilots" being thrown around after MAX fiasco.
Looks like once an issue hits closer to home, though, skygods are afraid to deal with a known and predictable issue - not to mention a total unknown MCAS was. Did they loose their right stuff? [ /sarcasm]

kalvado wrote:

LAXdude1023 wrote:

kalvado wrote:

Anyway, I am sure US skygods should be able to land with such a minor malfunction as a single non-functional piece of instrumentation.

You should research the cause of many airplane crashes before making such a ridiculous statement. Most of the time they can, but that could be very catastrophic.

This is in direct relation to "third world pilots" being thrown around after MAX fiasco.
Looks like once an issue hits closer to home, though, skygods are afraid to deal with a known and predictable issue - not to mention a total unknown MCAS was. Did they loose their right stuff? [ /sarcasm]

No it isnt. No pilot would EVER want to be on an aircraft with a malfunctioning altimeter. Thats a recipe for disaster.

par13del wrote:

kalvado wrote:

Of course, it may be a temporary fix. But one thing at a time.
Anyway, I am sure US skygods should be able to land with such a minor malfunction as a single non-functional piece of instrumentation.

Since the flights canceled so far are by foreign airlines whose pilots are trained to let the computers do the bulk of the work for safety reasons, not sure where the skygods fit in.

It could be these international carriers don't have the technology in place to calculate takeoff and landing performance in certain conditions (wet runway) at the airports with 5G NOTAMs. Back up procedures aren't developed overnight.

kalvado wrote:

Looks like altimeters - relatively high power transmitters - evaded being certified.

Altimeters - like any other transmitter - are certified by the FCC to ensure that they only transmit in their assigned band.
The FCC doesn't care whether your device can handle interference from other transmitters.

LAXdude1023 wrote:

kalvado wrote:

LAXdude1023 wrote:

You should research the cause of many airplane crashes before making such a ridiculous statement. Most of the time they can, but that could be very catastrophic.

This is in direct relation to "third world pilots" being thrown around after MAX fiasco.
Looks like once an issue hits closer to home, though, skygods are afraid to deal with a known and predictable issue - not to mention a total unknown MCAS was. Did they loose their right stuff? [ /sarcasm]

No it isnt. No pilot would EVER want to be on an aircraft with a malfunctioning altimeter. Thats a recipe for disaster.

RADIOaltimeter, if I may clarify. But who cares?

Revelation wrote:

kalvado wrote:

Of course, it may be a temporary fix. But one thing at a time.

Reminds me of a saying: there's nothing as permanent as a temporary tax!

kalvado wrote:

Anyway, I am sure US skygods should be able to land with such a minor malfunction as a single non-functional piece of instrumentation.

One data source would be malfunctioning, but it drives a lot of things (autoland, autothrottle, automatic thrust reverser deployment, etc).

Well, upgrade to input filter is the way to resolve things in either way. 26 years for affected Honeywell altimeter is a good production run. Even iconic 737 was upgraded since then. Twice.
And yes, this eerly reminds MCAS with multiple problems from single failure. Somehow no pilot is bringing "I can brave this, unlike those third world!". Looks like there is a bit more common sense coming when it hits closer to home. Which is a good thing, after all.

kalvado wrote:

FCC certification requirement was, for ages, that device should not cause interference to others, but should be able to tolerate interference from other devices. Again, technically speaking, any transmission from the aircraft is FCC licensed. It is mostly formal thing, but yet. Looks like altimeters - relatively high power transmitters - evaded being certified. And - news flash! - they are uncertifyable.
So grounding - like it happened to MAX - is immediate withdraw of affected equipment. Oh, yes, it hurts.
But aviation industry should know the value of playing by the rules!

Yet Jon's report linked above says FAA has cleared 45% of the altimeters in service?

I haven't read anything about how the FAA is going about doing that.

par13del wrote:

Since the flights canceled so far are by foreign airlines whose pilots are trained to let the computers do the bulk of the work for safety reasons, not sure where the skygods fit in.

Are you saying pilots on US airlines do the bulk of the work flying manually?

par13del wrote:

kalvado wrote:

Of course, it may be a temporary fix. But one thing at a time.
Anyway, I am sure US skygods should be able to land with such a minor malfunction as a single non-functional piece of instrumentation.

Since the flights canceled so far are by foreign airlines whose pilots are trained to let the computers do the bulk of the work for safety reasons, not sure where the skygods fit in.

You must be referring to EK. JL allows hand flying - in fact there are several procedures at Japanese airports that demand being able to do it well.

casinterest wrote:

The FCC sold the licenses, and the FAA failed to act expediently on an issue that has certified parts operating outside the licensed and advertised range.

The expedient thing for the FAA to do was nothing, which is pretty much what they did. No way did they have the resources to clear up their side of the problem within the time frame the telecomms planned for 5G C-band rollout. Certifying new equipment and procedures was going to take way longer than that. So why start a process that had no hope of bring finished in time to avert a problem?

Revelation wrote:

kalvado wrote:

FCC certification requirement was, for ages, that device should not cause interference to others, but should be able to tolerate interference from other devices. Again, technically speaking, any transmission from the aircraft is FCC licensed. It is mostly formal thing, but yet. Looks like altimeters - relatively high power transmitters - evaded being certified. And - news flash! - they are uncertifyable.
So grounding - like it happened to MAX - is immediate withdraw of affected equipment. Oh, yes, it hurts.
But aviation industry should know the value of playing by the rules!

Yet Jon's report linked above says FAA has cleared 45% of the altimeters in service?

I haven't read anything about how the FAA is going about doing that.

Everything is totally inconsistent. There is a scary document for 787, yet operators substituting 787 or troubled 777. 777 has no official document outlining the issue.
RJs either wait their turn for review or are all problematic.
Some altimeters are mentioned - but models are not named. Usually such information leaks out pretty quickly, but I don't see anything.

Looks like airlines have to follow official directives, which come from different channels and are inconsistent, so cancellation may be the safest option regardless.

hivue wrote:

casinterest wrote:

The FCC sold the licenses, and the FAA failed to act expediently on an issue that has certified parts operating outside the licensed and advertised range.

The expedient thing for the FAA to do was nothing, which is pretty much what they did. No way did they have the resources to clear up their side of the problem within the time frame the telecomms planned for 5G C-band rollout. Certifying new equipment and procedures was going to take way longer than that. So why start a process that had no hope of bring finished in time to avert a problem?

What timeframe are you talking about? Looks like 2 years - abeit 2 covid years - were there for sure, probably more than that.

kalvado wrote:

hivue wrote:

casinterest wrote:

The FCC sold the licenses, and the FAA failed to act expediently on an issue that has certified parts operating outside the licensed and advertised range.

The expedient thing for the FAA to do was nothing, which is pretty much what they did. No way did they have the resources to clear up their side of the problem within the time frame the telecomms planned for 5G C-band rollout. Certifying new equipment and procedures was going to take way longer than that. So why start a process that had no hope of bring finished in time to avert a problem?

What timeframe are you talking about? Looks like 2 years - abeit 2 covid years - were there for sure, probably more than that.

Perhaps you missed GalaxyFlyer’s earlier post that certifying new equipment was a minimum 4-6 year affair.

Aaron747 wrote:

kalvado wrote:

hivue wrote:

The expedient thing for the FAA to do was nothing, which is pretty much what they did. No way did they have the resources to clear up their side of the problem within the time frame the telecomms planned for 5G C-band rollout. Certifying new equipment and procedures was going to take way longer than that. So why start a process that had no hope of bring finished in time to avert a problem?

What timeframe are you talking about? Looks like 2 years - abeit 2 covid years - were there for sure, probably more than that.

Perhaps you missed GalaxyFlyer’s earlier post that certifying new equipment was a minimum 4-6 year affair.

May I disbelieve that?
787 - a totally new plane - was supposed to go from start to finish in 5 years. it took 8 or so.
737MAX full computer system was fully redesigned in somewhat over a year.
So 4-6 years for a single filter? No.
Still 4 years? Fire everyone on property and hire some professionals.

The problem with presently used RADALT systems is like cheap short wave radios in the past received a frequency band and thus several radio stations simultaneously as opposed to the desired single frequency and thus single radio station of the more expensive units. Surely the technology is there to make RADALT systems receive just the frequency band they are allotted, but the technology is more expensive, needs to be developed, certified and implemented, likely taking years. Like other posters have mentioned it is difficult to understand why this has not previously been given proper attention in the US . Besides, it is not only France that has different regulations to take care of the issue, it is more like the rest of the world .

This issue is limited to a certain frequency band not all of 5G. I have very fast 5G at airports because I use T-Mobile/Sprint. They were smart enough/ Lucky enough to put thier service on the N41 and N71 Band. This is 2.5 GHz (N41 Band) and 600 MHz (N71 band) They also have mm Wave at 39 and 28 GHz. The point is that while T-Mobile is laughing all the way to the bank, the rest of the carriers see it as unfair competition. T-Mobile is playing no where near the RADALT bands. T-Mobile seems to have concentrated it's 5G service into 4 frequency's that are not involved in the FAA FCC dispute.

hivue wrote:

casinterest wrote:

The FCC sold the licenses, and the FAA failed to act expediently on an issue that has certified parts operating outside the licensed and advertised range.

The expedient thing for the FAA to do was nothing, which is pretty much what they did. No way did they have the resources to clear up their side of the problem within the time frame the telecomms planned for 5G C-band rollout. Certifying new equipment and procedures was going to take way longer than that. So why start a process that had no hope of bring finished in time to avert a problem?

Doing nothing is not what the FAA is tasked with. They are part of an organization that has Safety as a core value of their mission. The statement below is not a good look. They have been discussing the issue for years... but yet no solution overnight? Well they grounded the Max for a few years waiting for a software fix costing that company billions. Where were they in preparing the operators of other planes that their technology was not compliant to the advertised documentation?

https://www.faa.gov/5g

Why are we only hearing about this now?
The FAA, the aviation industry, telecommunications companies, and their regulators, have been discussing and weighing these interference concerns for years, in the U.S. and internationally. Recent dialogue has helped to establish information sharing between aviation and telecommunications sectors and newly agreed measures to reduce the risk of disruption, but these issues are ongoing and will not be resolved overnight.

LAXdude1023 wrote:

No it isnt. No pilot would EVER want to be on an aircraft with a malfunctioning altimeter. Thats a recipe for disaster.

A faulty altimeter is a no go item. I'm not a pilot, but I spent 24 hours more than planned at BA's expense in Cyprus a few years ago because of a faulty altimeter on a 767. One of 3 on the aircraft IIRC, but they flew a spare from LHR on the next day's flight because 2 functional ones was insufficient.

danman132x wrote:

What baffles me is this is an airline enthusiast website, but so many people are defending the telecoms.

As in many on-line forums, a good percentage of the posters are not independent but institutional mouthpieces. The disinformation and misdirection comes fast and furious in these heady days.

Big Telecom, like Big Pharma,cares not a whit for public health or safety. What's a few broken eggs in a hen house of profits?

ItnStln wrote:

And what happens to the money that the cell companies paid for this frequency?

The government can put it in a Fund to pay health costs for the irreparable damage that will be done from "small" WTFs (Wireless Transmission Facilities) doting your neighborhoods!