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Author Topic: No cell phones on airplanes
TB Tabby
We Wish You a Merry Giftmas


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Here's one I just heard on the new episode of Mythbusters: You know how you can't use electronic devices while your flight is taking off and landing, and can't use cell phones at all, because they might interfere with on-board equipment and cause the plane to crash? Some people think this is just a scam by the airlines, forcing passengers to use the more expensive on-board phones to make their calls.

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I like to go down to the playground and watch the kids run and jump and scream, because they don't know I'm only using blanks.

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Squishy0405
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Aren't they going to allow cell phones soon?

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"Fate is like a strange, unpopular resturant, filled with odd waiters who bring you things you never ask for and don't always like."-Lemony Snicket

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Psihala
Little Sales Drummer Boy


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They're considering it.

And here is the FCC's advisory on it.

And this is the HTML version of an FCC 'kidzone' article of general topics regarding the FCC and their regulations.

~Psihala

ETA: And I found a blog with the FAA Cell Phone Ban Scam dated December 28, 2004 while I was looking for references towards possibly lifting it.

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Troberg
Angels Wii Have Heard on High


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The reason is very simple. It's the same reason most airlines don't have a seat row numbered 13. They don't want to make less educated people nervous. Irate passengers are much more dangerous than cell phones. There is absolutely no technical reason to ban them (or wifi/bluetooth equipment).

Cell phones do not interfere with instrumentation. My father was an ambulance helicopter pilot, with approx 20 000 flight hours (not all helicopter), and they used mobile phones to communicate with specialists and so on if needed.

As far as I know, there is only one documented accident caused by a mobile phone, and that was a pilot who was talking on the phone during final approach, didn't look where he was going and crashed.

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/Troberg

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Drainfluid
Deck the Malls


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The reason cell phones are banned has nothing to do with interference with the technology on the plane.

quote:
FCC rules currently ban cell phone use after a plane has taken off because of potential interference to cellular phone networks on the ground.
Its simple: if 300 people with "on" cell phones (not even actively talking)are in a plane, every cell phone mast that they pass over is trying to collect them, process them and then try and pass them on to the next mast as they zoom by at 800km/h. It causes the whole network to collapse.

New technology will install a cell phone receiver in the plane itself so the ground network won't be affected.

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Troberg
Angels Wii Have Heard on High


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Even that is not really true with the modern phone networks, as they are smart enough to handle this neatly.

Think about it, is a plane at 800 km/h with 300 passengers worse than big city car traffic? Not by a long shot. The cars are slower and don't see as many base stations, but there are many more of them.

A more important reason for the onboard base station is that the planes are fairly high (often 12 000 m), so reception may be bad. This is further complicated by the aircraft body being more or less a Faraday cage. The base station can use better equipment, an external antenna and send a stronger signal, so this will be a lesser problem.

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/Troberg

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Radon Girl
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I hope for the sanity and health of all aircraft passengers that they remained banned.

If I was stuck next someone who was nattering on a mobile for a 3 hour flight that person would most likely find said mobile inserted into the most convenient body orifice.

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Troberg
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I think the most inconvenient body orifice would be better.

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/Troberg

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DemonWolf
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quote:
Originally posted by Troberg:
Even that is not really true with the modern phone networks, as they are smart enough to handle this neatly.

Think about it, is a plane at 800 km/h with 300 passengers worse than big city car traffic? Not by a long shot. The cars are slower and don't see as many base stations, but there are many more of them.

A more important reason for the onboard base station is that the planes are fairly high (often 12 000 m), so reception may be bad. This is further complicated by the aircraft body being more or less a Faraday cage. The base station can use better equipment, an external antenna and send a stronger signal, so this will be a lesser problem.

But high traffic areas are there every day at predictable times. It also builds up and then falls in a predictable patters. It wouldn't be much to set the network to adapt to some increased traffic for an hour or two every day.
A passing airliner would be a sudden spike in traffic that passes before the network can adapt. Also, the plane may not run every day or might be delayed.

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IMJW-052804

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Fun with a 9mm
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Oh yes, being forced to listen to a 16-year-old cooing to her BF for 3 hours would just end badly for all involved.

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I'm not mean, you're just a big sissy. -Happy Bunny

The greatest trick the devil ever pulled was convincing the world he didn't exist.- Verbal Kint

Trespassers will be pelted with jellyfish.- Daniel Cluley

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Kev
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quote:
Originally posted by Drainfluid:
The reason cell phones are banned has nothing to do with interference with the technology on the plane.

quote:
FCC rules currently ban cell phone use after a plane has taken off because of potential interference to cellular phone networks on the ground.
Its simple: if 300 people with "on" cell phones (not even actively talking)are in a plane, every cell phone mast that they pass over is trying to collect them, process them and then try and pass them on to the next mast as they zoom by at 800km/h. It causes the whole network to collapse.

New technology will install a cell phone receiver in the plane itself so the ground network won't be affected.

That is the reasoning for the FCC ban. The FAA has their own rule and their reasoning is based on interference to navigation systems. They don't yet know for sure if they are safe. One of the linked articles says they are finishing up a study this year.

Both agencies would have to lift their ban for cell phones to be allowed on planes. If the FCC requires equipment to be installed on the planes I wouldn't expect the cash strapped airlines to be jumping to do it anytime soon, at least not on a large scale.

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StewPot
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Simply put, if the airlines truly thought the mobile phones were a serious risk to their equipment's functionality, they would confiscate them in security.
As it is, they just issue a friendly reminder to please be sure all cell phones are powered off. Can you imagine them saying, "Please ensure all firearms are unloaded and have the safety feature turned on."

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One of my favorite philosophical tenets is that people will agree with you only if they already agree with you. You do not change people's minds.
-Frank Zappa

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Troberg
Angels Wii Have Heard on High


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The rules about cell phones varies between airlines and countries, as they all have their own rules. Sweden allow them, but some airlines don't.

quote:
If the FCC requires equipment to be installed on the planes I wouldn't expect the cash strapped airlines to be jumping to do it anytime soon, at least not on a large scale.
It will be small money compared to the running costs of an airliner, and it will be a good selling argument, so I'll think they'll do it. They put monitors in every seat back and shows movies, how much do you think that costs?

[qoute]A passing airliner would be a sudden spike in traffic that passes before the network can adapt.[/quote]

There is, as far I can see, no need for adaption, just capacity. Either the network (actually the base stations) can handle the amount of traffic or they can't.

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/Troberg

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Kev
We Three Blings


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quote:
Originally posted by StewPot:
Simply put, if the airlines truly thought the mobile phones were a serious risk to their equipment's functionality, they would confiscate them in security.
As it is, they just issue a friendly reminder to please be sure all cell phones are powered off. Can you imagine them saying, "Please ensure all firearms are unloaded and have the safety feature turned on."

While I agree that they probably don't think they are a serious threat, in all fairness it's a little easier and safer to discourage someone from using a cell phone than a gun.

Troberg: you are right, it probably wouldn't cost that much for the equipment and that it would be selling point did cross my mind.

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Fun with a 9mm
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Oh yes, being forced to listen to a 16-year-old cooing to her BF for 3 hours would just end badly for all involved.

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I'm not mean, you're just a big sissy. -Happy Bunny

The greatest trick the devil ever pulled was convincing the world he didn't exist.- Verbal Kint

Trespassers will be pelted with jellyfish.- Daniel Cluley

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Drainfluid
Deck the Malls


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quote:
Originally posted by Troberg:
There is, as far I can see, no need for adaption, just capacity. Either the network (actually the base stations) can handle the amount of traffic or they can't.

You're concentrating solely on volume, which is only half the problem. The problem is the combination of volume and speed. By the time a mast has logged the presence of the phones in its airspace, those phones are already 3 masts further along, and the network falls further and further behind every minute. And there isn't only one plane in the sky at the time, there are dozens over busy routes, meaning the network is backed up across all directions. This obviously impacts on its functionality.
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Spikey
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I wonder, if they do lift the ban, whether there will be designated 'no phones' areas (like in trains), or if there will a small room or space at the end of the plane for people to go if they wish to use their phones.

At least, I really hope there will be.

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"The fact that "uvula" and "vulva" look and sound similar was just a happy coincidence." - Lainie

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Bunion
I'm Dreaming of a White Sale


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I am one of the ever shrinking minority of people that doesn't own a cell phone. I bought one about 8 years ago, but almost never used it so I just cancelled the service. I went to 3 movies in a row where someone's cell phone rang and they actually answered it and started talking. So basically I am not a big fan of cell phones. But I don't really see any real danger, because many times with modern electronic equipment, it isn't truely off even when it is turned off, plus all the countless times I am sure people forget to turn it off (or just plain don't bother to even do it.) So you'd think there would have been many instances of something happening with a plane by now.

That being said the last thing I really would want is to sit next to someone yapping on the phone for several hours. I don't know what it is about cell phones, but people seem to talk louder than they would on a regular phone. I guess they will need to add a "No Cell Section" of the plane for those people who like to read or try to take a nap.

Bunion

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You get more of what you want with a kind word and a gun then you do with a kind word alone.

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Simply Madeline
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quote:
Are cell phones and other personal electronic devices safe to use on airplanes?

It depends who you ask, but a new study conducted by researchers from Carnegie Mellon University and featured in an article in technology magazine IEEE Spectrum, says they could be.

"The data support[s] a conclusion that continued use of portable RF-emitting [radio frequency-emitting] devices such as cell phones will, in all likelihood, someday cause an accident by interfering with critical cockpit instruments such as GPS receivers," the article said.

The research is believed to be the first of its kind and comes as the FCC is soliciting opinions from the public about allowing cell phone use in airplane cabins.

From This Article
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Ganzfeld
Let There Be PCs on Earth


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Thanks Madeline. That research paper is also available on the web:
http://www.spectrum.ieee.org/mar06/3069

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rushrulz
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What I heard is that once, when there was an accident or some other incident, they found out that someone was using a phone at the time it happened and worried that it was related, so to play it safe, they issued a flat ban, even though there was no proof that the phone was the cause.

But yeah, it's bad enough that I have to hear cell phone conversations as it is, never mind when I'm trapped on a plane in close quarters.

What about laptops? I don't think mine's putting out any "signals."

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RichardM
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One reason that cell phones and other radio frequencies emitting devices might, no do but might, cause interference with critical systems on board an aircraft is by raising the electrical potential of the body of the aircraft in relation to the earth. In other words, instead of the body of the aircraft being at 0 volts, it might could possibly but probably not, be at 1 volt. And yes, that would be enough to cause a problem under some conditions. Hope I used enough "mights" "coulds" and other such words so that people don't try to argue with me that this doesn't really happen. That is what the FAA is studying.
Richard the electrical engineer and ham radio operator but not an expert on aircraft or radios.

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WildaBeast
Let There Be PCs on Earth


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quote:
Originally posted by rushrulz:
What about laptops? I don't think mine's putting out any "signals."

Any electrical device will emit some electromatic radiation. That's why the picture on your TV might go a little snowy when you turn on your blender (back in the days when TVs used rabbit ears, anyway). The FCC requires manufactures to test their products to make sure they don't cause too much interference.

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"Unseasonable is an odd word to begin with. It sounds like it's describing something that it's impossible to sprinkle pepper on." -- Nonny

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Etienne
We Three Blings


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The last shipping company I worked with had banned cell phones from their bridges (Officially, because in reality... Face it, it's where you get the best reception)

Their reasons for the policy where that a) It distracted the navigational watch, which is entirely true and b) It had interfered with the steering system of one of the vessels they managed.

I don't know if this is true, as it didn't reference any verifiable data, but it's out there. I strongly doubt it's veracity, because of the way a steering system works.

Of course, a ship isn't a plane, and a plane isn't a ship.

Finally, I've never seen a GPS receiver go wonky-wonky because of a cell phone, although we never used one near the antennas. (We were under them, usually :-D)... GPS reception doesn't suffer -AFAIK- from the use of MF/HF, X and S band radar, or SatCom transmitters, and those are much, much more powerful than a cell phone, although in a different frequency band.

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Ganzfeld
Let There Be PCs on Earth


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About other electronic devices, there is one anecdote that's been going around that one plane captain discovered his navigation system was 30 degrees off (a lot!). The flight attendants asked a passenger to turn off his DVD player. The problem went away. That's hardly scientific evidence, but if you've ever experienced any weird interference (such as picking up radio on a record player or something like that) then you know these things can happen. I think it's probably still a good idea not to allow electronic devices to be turned on during takeoff and landing.
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Doug4.7
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quote:
Originally posted by RichardM:
One reason that cell phones and other radio frequencies emitting devices might, no do but might, cause interference with critical systems on board an aircraft is by raising the electrical potential of the body of the aircraft in relation to the earth...

No. This is NOT true. I know. The potential of an aircraft is WAY above a few volts. In my work, we have to deal with aircraft potentials of KILOvolts.

As for sitting near someone using the cell phone, what is the big deal? That is what headsets playing deathmetal are for. I would rather sit next to a person yakking on the phone than someone with body odor.

There is no safety reason NOT to allow cell phones on aircraft. That is NOT the issue.

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And now for something completely different...

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Lainie
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quote:
Originally posted by Bunion:
I don't know what it is about cell phones, but people seem to talk louder than they would on a regular phone.

When the FCC first started considering lifting the ban, I heard an expert (don't remember his qualifications) on NPR who said cell phone users talk louder because, on a cell phone, you don't hear your own voice going across the line.

quote:
Originally posted by Troberg:
I think the most inconvenient body orifice would be better.

[lol]

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How homophobic do you have to be to have penguin gaydar? - Lewis Black

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Ganzfeld
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quote:
Originally posted by Doug4.7:
There is no safety reason NOT to allow cell phones on aircraft. That is NOT the issue.

I don't undertand your basis for being so sure about this opinion. The authors of the study linked above disagree with you. How can you be so sure? (I'm asking as an honest question. No snark.)

Also, if safety is no issue, do you have any guess as to why the rules have been kept in place?

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WildaBeast
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quote:
Originally posted by Doug4.7:
The potential of an aircraft is WAY above a few volts. In my work, we have to deal with aircraft potentials of KILOvolts.

Could you clarify what you mean by "the potential of an aircraft"? The potential of what part of the aircraft, and in relation to what?

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"Unseasonable is an odd word to begin with. It sounds like it's describing something that it's impossible to sprinkle pepper on." -- Nonny

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Jason Threadslayer
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Selected ASRS PED reports.

pg 65 is interesting -- 15 deg uncommanded turn when mobile phone rang
pg 102 has report of radar going offline possibly due to walkie-talkies
pg 107-108 has the report Ganzfield mentioned

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All posts foretold by Nostradamus.

Turing test failures: 6

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Doug4.7
Angels Wii Have Heard on High


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quote:
Originally posted by Ganzfeld:
quote:
Originally posted by Doug4.7:
There is no safety reason NOT to allow cell phones on aircraft. That is NOT the issue.

I don't undertand your basis for being so sure about this opinion. The authors of the study linked above disagree with you. How can you be so sure? (I'm asking as an honest question. No snark.)

Also, if safety is no issue, do you have any guess as to why the rules have been kept in place?

I fly in aircraft where we put out a heck of a lot more RF radiation than any cell phone (we even get to shoot lasers at clouds). Our safety guys are downright paranoid about safety and they monitor this stuff quite closely. So far, they have seen nothing that would set them off (and they are REAL easy to set off). Funny thing is, I use GPS REAL-TIME in the aircraft for our stuff and we've had no trouble with cell phones. I would be PO'd if I lost GPS on my instrument (I use GPS for accurate time ticks). So far, I haven't. Now it is true, they want us powered down at takeoff and landing, but most of that is because they want to concentrate on getting the aircraft on/off the ground and not have to deal with us stupid scientists. I hear, “Shut up, and sit down!” a whole lot from them.

Now reading that article, I am curious as to the status of the grounding of the GPS receivers that lost sync when the cell phone was turned on (or that nav system with the 30 degree error when the DVD was turned on). I know that a poorly grounded instrument can be “messed up” by all sorts of things, including a low power cell phone or any other source of RF. In other words, the cell phone may simply be pointing out a defect in the GPS receiver (or other navigational equipment) or how it was installed. I know all about poorly installed equipment.

I would believe the line in the paper that says cell phones may lower margins in navigation systems. Any RF will do that. You can solve the problem by either banning all on-board electronics, make sure your critical systems are put together right, or have greater margins.

As for picking up the ground cell system from an aircraft, it will work, but will likely not work well. The system was not designed to pick up signals ABOVE the cell towers moving at aircraft speeds. I bet you would get a lot of dropped calls. The pico-net idea would be good (i.e., have the cell “tower” on the plane). The good news there is most (all?) cell phones only use enough power to reach their tower, and so if the “tower” was on the aircraft, you would have lower power output and less interference. Part of the problem now is the cell phones have to “shout” to get heard by a tower 30,000 ft below them (with a radiation pattern that is NOT looking for a phone ABOVE the cell tower). So the cell phones are broadcasting at max power (still very low power, but still...).

Studies need to be done with correctly installed systems AND ones where the grounding (or other aspects) were not done to code. That might help shed some light on this issue.

Would I fly in a plane with people using cell phones? Yes. Would I do so while making an IFR landing where we are using ONLY GPS to get us on the ground? No. However, I would NOT want to be in a plane that was making an IFR landing using only GPS because GPS is easy to screw up.

As for the potential of the aircraft thing, any time you fly into a cloud (any cloud) the aircraft will charge up to the point where the potential of the skin of the aircraft in relationship to the ground is huge. I have put 20 kilovolts on an aircraft (in clear air) to do my research, but simply flying into a cloud will dwarf that potential. The bottom line is a small RF transmitter will produce a much smaller "voltage" than simply flying into a cloud.

ETA:I read those ASRS reports, and they really do sound like faulty wiring.

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And now for something completely different...

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Troberg
Angels Wii Have Heard on High


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quote:
One reason that cell phones and other radio frequencies emitting devices might, no do but might, cause interference with critical systems on board an aircraft is by raising the electrical potential of the body of the aircraft in relation to the earth. In other words, instead of the body of the aircraft being at 0 volts, it might could possibly but probably not, be at 1 volt. And yes, that would be enough to cause a problem under some conditions.
As some people has said, the potential of the aircraft is a non issue. Do you have any idea what potential the clouds can build up? How much does it take for lightning to jump the gap between the clouds and the ground?

How much other radio signals does an aircraft recieve? Cellphones on the ground? On the airport (how many call to say they have arrived the first thing they do?)? TV? Radio? Trust me, the air is pretty thich with radio waves anyway, and most of them are on the outside of the aircraft, where the antennas are.

I still maintain that the reason is that some people still think we don't know what electricity, radio waves or EM fields are, despite having used them extensively for a century.

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/Troberg

Posts: 4360 | From: Borlänge, Sweden | Registered: Nov 2005  |  IP: Logged | Report this post to a moderator
Ganzfeld
Let There Be PCs on Earth


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quote:
Originally posted by Doug4.7:
I fly in aircraft where we put out a heck of a lot more RF radiation than any cell phone (we even get to shoot lasers at clouds). Our safety guys are downright paranoid about safety and they monitor this stuff quite closely. So far, they have seen nothing that would set them off (and they are REAL easy to set off).

This explains a lot to me. You're on an aircraft that is known to produce lots of RF (although a laser, as you know is not RF) so it is carefully checked for anything that might go wrong. Ordinary transportation planes do not and are not. Nearly all of your instruments can probably be checked beforehand. Passenger equipment can't. You probably deal with a small number of aircraft, too, so each aircraft can probably be inspected carefuly. Faulty wiring or not, they have to make do with what they have and, if any of my recent adventures in secuirty checks is an indication, passengers take incidents very seriously. I don't think there's much of comparison between the RF safety issue in your case and the RF safety issues faced by airlines.

I also don't think your high RF potentials mean a lot because it's just noise, not a signal. Any electronics can be tested under various amounts of radio noise but the question is how they will handle signals or noise that looks more like a signal than what you'd get from passing through a cloud.

Just my impressions. I admit don't know much about this subject.

Posts: 4922 | From: Kyoto, Japan | Registered: Sep 2005  |  IP: Logged | Report this post to a moderator
Doug4.7
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quote:
Originally posted by Ganzfeld:
This explains a lot to me. You're on an aircraft that is known to produce lots of RF (although a laser, as you know is not RF) so it is carefully checked for anything that might go wrong. Ordinary transportation planes do not and are not. Nearly all of your instruments can probably be checked beforehand. Passenger equipment can't. You probably deal with a small number of aircraft, too, so each aircraft can probably be inspected carefuly. Faulty wiring or not, they have to make do with what they have and, if any of my recent adventures in secuirty checks is an indication, passengers take incidents very seriously. I don't think there's much of comparison between the RF safety issue in your case and the RF safety issues faced by airlines.

I can see your point. It does seem that I had to sacrifice my first born child to get my instruments on the aircraft. That, or lots of blood sacrifices. BTW, the laser has a whole bunch of electronics to get it to fire, and they produce MORE than their share of RF interference (we used to be across the isle from them and they would mess US up).

Like it or not, we (as in people in general) are doing the cell-phone-on-aircraft tests as I write this. I have NOT been on a commercial flight (and I fly a lot) where someone has NOT used a cell phone “illegally” (i.e., while in flight, while on the ground, left it on in their carry on luggage, etc.). So far, it hasn’t crashed an aircraft (knock on wood). My guess is it won’t. The reason I say that is aircraft have systems that are redundant and most every system has a backup. There are very few single failure crashes. It is usually “item A”, then “item B”, and THEN “item C” caused the crash. Had the first two not happened, “item C” would not have crashed the aircraft. So, if you have a poorly installed GPS system, the aircraft uses the GPS system ALONE to land the aircraft, and Joe Isuzu gets on his broken cell phone to call his mistress at the airport, AND the pilot ignores the odd commanded right rudder, you could get a crash.

There are two general solutions to this problem (cell phones on aircraft). You can enforce the ban more strictly (i.e., arrest anyone caught with an operating cell phone on an aircraft), or you can “harden” the plane’s electronics to handle the interference. The second solution will not cost as much as one might think. From my aircraft experience, if the equipment is put in correctly AND maintained correctly, interference from something as low power as a cell phone is NOT going to be an issue. It is only when you let signal wires become frayed or let grounds detach, AND you have a defective PED will you have troubles. It will be difficult to enforce the “no defective PEDs on aircraft” rule, but to require aircraft to check systems when something does interfere should actually be part of the current maintenance schedule. If a cell phone can bring down an aircraft, just think what a single lightning strike could do (yes, aircraft are periodically hit by lightning).

We can put our heads in the ground and hope that no one brings on a broken cell phone on to an aircraft with poor wiring, or we can be proactive and make sure that broken cell phone does not wipe out a flight critical system.

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And now for something completely different...

Posts: 4164 | From: Alabama | Registered: Oct 2005  |  IP: Logged | Report this post to a moderator
Delta-V
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quote:
Originally posted by Troberg:
The reason is very simple. It's the same reason most airlines don't have a seat row numbered 13. They don't want to make less educated people nervous.

Um, Cite? [Smile]
I'm pretty sure most airlines have a 13th row. Certain aircraft, when configured with a 1st Class section, won't, because the 1st Class galley occupies that space.

Links to many seating charts

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"My neighbor asked why anyone would need a car that can go 190 mph. If the answer isn't obvious, and explaination won't help." - Csabe Csere

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