So PEDs are okay on board?
 

I think allowing the use of electronics in aircraft is a mistake.

http://www.nzherald.co.nz/world/news...ectid=10536660

I have been using my laptop on hundreds of flights and have seen hundreds of other passengers do it as well. I have also seen hundreds of passengers use their iPODs and other PEDs. I'm talking about 747s, 767s, 757s, 737s, RJs, ATRs, A340s, A330s, A320s, A300s, and some models I can't remember. Never experienced any incidents, so perhaps QF is looking at the wrong direction? or trying to sideline the real blame? whatever it may be.

So because you've never seen a problem, one can't exist? That's the most ridiculous statement I've ever heard. Besides, I had no idea you were an RF engineer.

On just about EVERY flight over an hour long there are dozens of passengers using PEDs. That amounts to <u>hundreds of thousands flights a day</u>.

How many reports do you see that the plane lost altitude due to some electronic malfunction because of a PED was used on board?

Not many if any, until this one.

To me that's pretty good evidence that PEDs are not interfering with the planes electronics.

You can believe what you want.

<i>How many reports do you see that the plane lost altitude due to some electronic malfunction because of a PED was used on board?

Not many if any, until this one.</i>

Let's see - should I take your word for it, or the IEEE's? Here's a report from that organization: http://www.spectrum.ieee.org/mar06/3069

&quot;...the data support a conclusion that <b>continued use of portable RF-emitting devices such as cellphones will, in all likelihood, someday cause an accident</b> by interfering with critical cockpit instruments such as GPS receivers. This much is certain: there exists a greater potential for problems than was previously believed.&quot;

PEDs = Personal electronic devices. In my book and as far as this discussion was concerned I thought we were talking about laptops, iPODs and similar devices. I never mentioned cellphones.

In fact the article you posted a link to never mentions cellphones.

Make up your mind as to what you want to object to?

In fact, I'm all against allowing cellphone use during a flight, not because I buy into the theory that they are dangerous electronically, but because they will be dangerous in terms of passengers having a rage over the one or two obnoxious passengers telling the whole world that they are at 33,000ft above sea level and isn't it cool they can talk to their friends/family.....:-D

<i>In fact the article you posted a link to never mentions cellphones.</i>

You're either on crack or you didn't read the IEEE article. Both cell phones and other electronic devices are discussed exhaustively. I object to the cavalier use of <u>all</u> of them.

It's obvious you don't care to learn anything about this issue; you're only interested in being right.

First, 95% of all PEDs (or whatever you wish to call them) do emit small amounts of RF radiation. Yes, even some radio receivers. Fortunately, modern technology allows them to be well shielded to keep the measurable emissions at an extremely low and generally acceptable level outside the device.

Nonetheless, no matter how much we try to shield (and no matter how good the aircraft's defensive measures are) it is still possible that stray radiation can get through, be amplified by unrelated &quot;stuff&quot; around (yes, possible), and find its way into critical navigation equipment. To induce a glitch into the aircraft's systems during critical phases of flight is potentially dangerous.

That one's experience shows millions of instances of noneventful usage goes to compliment the designers on their attention to reduction of the emissions. But the threat has not yet been 100% eliminated.

We go through excruciating levels of security so that one person's shoes don't blow up an aircraft; I see a similar a risk with RF interference. And if it can be prevented by simple measures such as turning the equipment off during critical phases of flight, so be it.

Credentials: BSEE, former professional RF Engineer, former member IEEE.

I know that before they made the decision to ban electronics during takeoff and landing, but allow them during cruising, they did studies and concluded there were no risks (actually, I think they also concluded there were no risks during takeoff and landing, also, but banned them then out of an excess of caution, I think based on their feeling that there was time to react to an event during cruising, but not during takeoff and landing).

However, those studies were done some years ago, and the IT industry is subject to frequent changes. I'm not sure, thus, that things like wireless connectivity were evaluated during the initial studies, as they may not have existed then.

It would be comforting to know that the studies are ongoing and cover the latest technology. but it is certainly possible that the FAA, which seems to be constantly underfunded, would not have a program of continuous testing.

<i>...they did studies and concluded there were no risks...</i>

What?!?!

<b>&quot;Our research has indicated that PED interference occurs at an appreciable rate and that some of these events create hazardous situations. The rapid growth of wireless and other devices emitting RF radiation poses increasing risks for airlines.&quot;</b>

(Thank you, NFZ. Finally, someone on the same page with me. I don't have an EE, but I've been a ham since 1956, so I can follow a discussion with an experienced eye.)

<i>You're either on crack or you didn't read the IEEE article.</i>,

chill out Robes, I meant the OP link, not the follow up post.

Again. make up your mind what you want to debate about, is it PEDs or cellphones?

because the QF article pointed a finger at somebodies laptop or iPOD, not a cellphone.

What specific findings and/or recommendations of the IEEE do you want to take issue with?

Whatever Robes....

It's kind of strange that laptops, iPODs and such have been flying with us for years and AFAIK, there was not one crash attributed to the devices.

And wasn't it our own FAA that about a year ago started to have hearings about cellphone use during flights? They came to the conclusion that the use could be controlled as far as the electronics go, but they wanted the input from the traveling public to see if they wanted to hear others chatter about nothing for hours when the seat mate really has no choice but to sit there and listen to it. .

As I stated in my earlier post, I'm against it, but not because I buy into the interference BS.

On that note I will leave this room.

Believe what you want.

btw, AA, VirginAmerica are in a test mode to offer high speed internet during their domestic flights using land based cellular type towers. That has been approved by the FAA, it's just a matter of working out some of the kinks with the system. Some major international airlines did offer Boeing Connexion internet couple of years ago which was satelite based, but Boeing closed the shop on that because the economics were just not there. It was a very expensive system and it was brought on line during airlines difficult times so not many airlines as Boeing hoped signed up to it thus making it too expensive for the few that did. Not one of those planes crashed.
Amazing, isn't?

Here it is:

<i>American Airlines' plans to offer in-flight broadband access across certain transcontinental flights took a major step forward yesterday. Aircell, the airline's in-flight Internet access provider, has received two important approvals from the FAA, and is now cleared to begin rolling out its service.

The new permits cover device manufacturing and functionality, so Aircell is now cleared to both produce and deploy its technology on any aircraft that's cleared to use it. Currently, Aircell is focusing on AA's Boeing 767-200 transcontinental fleet, and has additional plans to work with Virgin America. Aircell has stressed, however, that its technology is not airline-specific, and can theoretically be deployed by any US airline.

We've previously reported on Aircell's plans to offer its service via a series of 92 cellular towers scattered across the 48 states. Access points will be spaced evenly throughout the aircraft, and will communicate using the 3GHz spectrum. A set of three antennas (one on top of the aircraft and two on the bottom) will keep the plane communicating with terra firma. </i>

http://arstechnica.com/news.ars/post...-airlines.html


I guess you better start writing your congressperson to stop this insanity.....

It's one thing when the WiFi system is a) engineered to avionics specifications, b) installed by professionals who know infinitely more about the subject than the typical consumer ever will, and c) periodically tested rigrously for spurious and stray RF emissions.

It's quite another when J. Random Passenger brings some Chinese-made Wal-Mart crap on board and fires it up during a CAT III landing.

Get the distinction, Marconi?

oh I do, but I not so sure about you...genius!

Tell me, how will it be different if I bring a high end laptop to do my internet work during a flight, and my seatmate brings some cheap end version of his to do his?

Just because the the Aircell Co. tests everything as far as the connection is concerned, they will NOT test the laptops that the passengers will be using.

Get IT NOW!

or are you that dense?

The crew has control of the network's power, so that's covered.

Since laptops aren't the kind of thing that can be surreptitiously operated during critical flight phases or when the Captain has prohibited their use, I don't see much danger there. They power down (at least to Standby) when the lid is closed at the request of the FAs.

But some clown watching his porn on an MP4 player that misbehaves could bring down an airplane. Don't tell me if you think IEEE is wrong - I don't care.

My reading of the linked article is that it wasn't the laptop per se that was thought to be the problem -- it was the wireless mouse.

The NZ article is only the tip of a really dangerous iceberg. Read the second article I linked. The folks at an internationally accredited electrical engineering institute have serious doubts about the safety of <u>all</u> sources of radio-frequency radiation brought on board and used by passengers - cell phones, radio receivers including GPS, laptops, Bluetooth devices, PDAs, games, music players...

http://www.spectrum.ieee.org/mar06/3069

I will re-iterate from that article a quote that I think is nothing less than bone-chilling: &quot;...the data support a conclusion that <b>continued use of portable RF-emitting devices such as cellphones will, in all likelihood, someday cause an accident</b> by interfering with critical cockpit instruments such as GPS receivers. This much is certain: there exists a greater potential for problems than was previously believed.&quot;

ooohhh,

watch out, the planes are falling out of the sky.....

hundreds of thousands of flights a day all over the world, millions of laptops, iPODs, etc... being used on all these flights.

better write your congressperson to stop this insanity......

That line of &quot;reasoning&quot; is known as The Gambler's Fallacy.

Hundreds of thousands of normal 747 flights preceded the TW800 disaster, when an obscure defect in the design of the 747 fuel system blew up the plane, killing all 230 on board in a horrific breakup scenario.

The more PEDs are used on board, the greater the odds of a catastrophe. Have someone who understands statistical inference and risk analysis read the IEEE report to you.

so, should be ban all cars that don't get checked daily for brakes, or steering or whatever? because they will on occasion cause accidents and in some cases, deadly accidents. Perhaps it's not 200 people at the same time, but when you add it up daily, then I will take a guess, but I believe more people die because of some others not taking care of their cars on regular basis. Should we ban alcohol all together? Lots of alcohol related deadly accidents, fights, arguments. Should we ban red meat, you know, the stuff that will eventually give you a heart attack if consumed in large quantities.

Your argument is ridiculous. Not one plane fell to the ground because of PEDs, not one that I know of. Yet, you want to ban the use of PEDs because of a chance of it happening one day according to somebody's statistics?

I would ask &quot;what part of the IEEE report don't you understand?&quot; - but I already know the answer: all of it.

The nzherald article doesn't really say much of anything: a laptop is being investigated as the cause.

It mentions a July incident where a wireless mouse was blamed. Blamed does not mean guilty.

I read parts of the ieee article and saw that they tested for emissions in the passenger compartment. Did they do any measuring of intereference in the cockpit of that originated in the passenger compartment? Did seem that the EEs who wrote the article had their minds made up even before their experiments.

Here is an article from a trusted (by me) source:
http://tinyurl.com/54ktas
&quot;Qualification levels related to high-intensity radiated fields (HIRF) for new airplane equipment are higher than almost any level of emissions from passenger PEDs.&quot;

Among much else, it does recognize the potential from newer PEDs.

Last night I saw an article somewhere about the potential for digital tv broadcasts to be disrupted by a wireless internet system that would use the &quot;white space&quot; between the tv broadcast frequences.

I hesitate to get into any arena with AAFF and Robespierre, but I want to ask about distinctions between cellphones and other 'PEDs' -- I skimmed the Spectrum article and it seems to focus on cellphones, otherwise just saying that all 'PEDs&quot; on a generic list &quot;emit radiation.&quot;

But some are designed to actually transmit and receive signals -- e.g., a cellphone, a WiFi-equipped (and active) laptop, and a wireless mouse. In addition, the article said that there are significant variations among cellphones, cellphone types, frequency bands affected, and so on. There's plenty of room for much more study.

It seems to me that it's folly to argue from past history as a guarantee of future performance (viz., the stock market), but it's also probable that a blanket ban of all &quot;PEDs&quot; isn't ultimately necessary (even if it were feasible).

I would LOVE it if no one could ever use a cellphone in the air, under any circumstances. But it does seem some more refined scrutiny of what does and doesn't cause problems at which frequencies/bands, in what circumstances, would be prudent and more enlightening than an all-or-none debate.

<i>&quot;Qualification levels related to high-intensity radiated fields (HIRF) for new airplane equipment are higher than <b>almost</b> any level of emissions from passenger PEDs.&quot;</i>

Doesn't that <i>almost</i> bother anyone else? It says that there <u>are</u> passenger PEDs that exceed even the new limits - and the statement says nothing about older equipment, which probably constitutes 90% of the planes in the air.

<i>But it does seem some more refined scrutiny of what does and doesn't cause problems at which frequencies/bands, in what circumstances, would be prudent and more enlightening than an all-or-none debate.</i>

The scariest part of the problem is that the frequency and intensity of spurious emissions that can be generated by malfunctioning equipment cannot be predicted at all. We know what some of the failure modes <i>might</i> be - and design against them - but it is a fact of physics that all of them cannot be imagined.

I think we're on very thin ice - and I hope to gollygosh I'm wrong.

I have yet to read of an accident caused by RF emissions from any personal electronic device on board an aircraft, even those that are transmitters by design.

Furthermore, the prohibitions that exist and those that are practiced do not coincide with the theoretical risks. Devices that may produce a great deal of RF emissions are allowed, while others that probably produce none are prohibited. And some that should theoretically be prohibited are ignored, such as electronic watches (nobody has ever conclusively determined that electronic watches do not interfere with aircraft avionics, even though the law requires this).

Overall, the risk is massively overstated. If an airliner can withstand a direct strike by lightning (and it can), the feeble emissions of laptops and video cameras aren't going to make a difference. Even a cell phone isn't going to make much difference, since any system sensitive enough to be perturbed by a cell phone inside the aircraft would also be vulnerable to transmissions from outside, which are legion.

There are other risks that are much more important, such as those created by airlines that pressure their pilots to load only the minimum amount of fuel required by law, or airlines that give pilots such erratic working hours that they fall asleep in the cockpit, or passengers who insist on smoking in the toilets.

<i>I have yet to read of an accident caused by RF emissions from any personal electronic device on board an aircraft, even those that are transmitters by design.</i>

The discussion isn't about past accidents - it's about the potential for future ones. But devices that are transmitters by design are the last place I would expect a problem to come from, because they are engineered to limit spurious and sideband emissions. Electronic toys and other things that aren't expected normally to transmit are not.

<i>Furthermore, the prohibitions that exist and those that are practiced do not coincide with the theoretical risks. Devices that may produce a great deal of RF emissions are allowed, while others that probably produce none are prohibited. And some that should theoretically be prohibited are ignored, such as electronic watches (nobody has ever conclusively determined that electronic watches do not interfere with aircraft avionics, even though the law requires this).</i>

We'll get a better handle on which ones are riskier from examining the crash sites.

<i>Overall, the risk is massively overstated. If an airliner can withstand a direct strike by lightning (and it can), the feeble emissions of laptops and video cameras aren't going to make a difference. Even a cell phone isn't going to make much difference, since any system sensitive enough to be perturbed by a cell phone inside the aircraft would also be vulnerable to transmissions from outside, which are legion.</i>

Avionic systems know what the broadband noise signature of a lightning bolt looks like, and they're trained to ignore it (their common-mode rejection ratios are very high). The problem will come when a PED emits something that looks very much like normal data that the system fails to recognize as extraneous.

<i>There are other risks that are much more important, such as those created by airlines that pressure their pilots to load only the minimum amount of fuel required by law, or airlines that give pilots such erratic working hours that they fall asleep in the cockpit, or passengers who insist on smoking in the toilets.</i>

Let's talk about other risks tomorrow.

&quot;almost any level&quot; simply means that they tested to a level well beyond any real world scenario.

<i>folly to argue from past history as a guarantee of future performance (viz., the stock market)</i>

It is not folly in this case. It is physics. The stock market operates on greed and fear.

<i>Author: mrwunrfl
Date: 10/12/2008, 02:26 pm

&quot;almost any level&quot; simply means that they tested to a level well beyond any real world scenario.</i>

I think that's a rather cavalier interpretation of the phrase. I take it to mean &quot;most, but not all&quot; - as in

&quot;Qualification levels related to high-intensity radiated fields (HIRF) for new airplane equipment are higher than <s>almost any level of</s> [most, but not all] emissions from passenger PEDs.&quot;

<i>folly to argue from past history as a guarantee of future performance (viz., the stock market)

It is not folly in this case. It is physics.</i>

These articles describe a mosaic of anecdotal events - past history - that forms a threatening pattern:

http://www.boeing.com/commercial/aer..._textonly.html

http://www.spectrum.ieee.org/mar06/3069

It is a fact that no direct causal link between PEDs and flight systems anomalies has been documented - at least none that can be reproduced under similar but different conditions. But it is also a fact that certain combinations of coincident conditions capable of affecting flight safety <u>have</u> occurred.

In several instances, air crew could verify the role of a PED affecting aircraft control by turning it off, noting that the anomaly ceased, then turning it on again, whereupon the anomaly reasserted itself.

The fact that these &quot;relationships&quot; cannot be reproduced in the laboratory is insignificant. What matters is that they <u>have</u> occurred - <i>in flight</i>. Since the exact nature and extent of the threat cannot be quantified, I feel that until it can, the operators should err on the side of caution.

What is insignificant is the nz herald article and the blame (by who?) that a wireless mouse caused a plane to go off course. The didn't prove it, did they? Or did they repeatedly during that flight click the mouse and see the plane go off course?

The wireless mouse is blamed but that doesn't mean it was guilty. An airline suspects a laptop that is not the same as saying that it was the cause.

That is the same Boeing article that I linked. It does say: &quot;as a result of these and other investigations, Boeing has not been able to find a definite correlation between PEDs and the associated reported airplane anomalies&quot;.

That Boeing article is cautious in what it says.

But it is not hysterical.

I didn't see how the NZ incidents (laptop and mouse) were followed up. But the Boeing report was unequivocal:

&quot;A passenger’s palmtop computer was reported to cause the airplane to initiate a shallow bank turn. One minute after turning the PED off, the airplane returned to &quot;on course.&quot; When the unit was brought to the flight deck, <b>the flight crew noticed a strong correlation by turning the unit back on and watching the anomaly return, then turning the unit off and watching the anomaly stop</b>.&quot;

Not convinced, eh? I hope your family isn't on the flight that proves you're wrong.

Scary Monsters......

http://www.youtube.com/watch?v=NHywdqH3F6Y

Great. Deny the threat and it'll go away. Real smart.

To be honest with you, Robes, I see you as the person screaming &quot;fire&quot; in a crowded theater when there is none.

This is a non-issue, but you believe what you want.

And I see you as the guy who says &quot;hold my beer and watch this.&quot;

Better scientists than I (and you, needless to say) have determined there's a hazard. Ignore it at your peril.