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  (Source: NBC Universal)
Passengers are acting out against the rules and even hurting one another

The Federal Aviation Administration (FAA) worries that electronic device use on planes places passengers in harm's way, but the real issue is that the FAA is spreading fear about an issue that hasn't been proven yet.

The FAA has set rules that make it so passengers cannot use electronic devices like smartphones, tablets and e-readers during takeoff and landing on a flight. However, there is no solid proof that electronics affect the way a plane performs. This has been in question for some time, but the FAA continues to impose these rules on passengers, and it has caused panic and even injuries among those who travel by plane.

For instance, a 68-year-old man punched a 15-year-old on a plane when the teenager refused to turn off his smartphone during a flight. According to the man, he was doing it to save the entire plane from any harmful consequences.

Just a couple of months ago, a passenger was arrested in El Paso when he decided not to turn off his cell phone during landing. Last month, another passenger did the same when landing in New York and a swarm of cop cars were waiting for him once he exited the plane.

Of course, many also remember the incident where Alec Baldwin was kicked off a plane in 2011 for playing Words With Friends.

This goes to show that the FAA is causing more trouble by making people believe that electronics are an issue when they may very well not be.

Back in March, the FAA said it would review the effects of tablet/e-reader use during takeoff and landing.

 Pilots can already use iPads during the entire flight [Image Soure: The AirplaneNut]

The FAA likely put this testing off due to costs and the amount of testing required for these devices to pass. In order for the FAA to approve the use of e-readers and tablets during takeoff and landing, each kind of device needs to be tested. For example, an iPad cannot be tested alone; the iPad 2 and the new iPad must be tested as well. There are already several versions of the Kindle available as well, such as the Kindle Fire tablet, and many other Android-powered tablets on the market. There are now Windows 8 tablets on the market too.

In early December 2011, the FAA raised a few eyebrows when allowing American Airlines pilots to use iPads in the cockpit. The FAA allowed iPads to replace paper manuals and charts, and they could be used during takeoff and landing. The FAA argued that allowing two iPads in the cockpit was a significantly different scenario than several passengers using several devices for longer periods of time.

Earlier this month, the Federal Communications Commission (FCC) pressured the FAA to allow greater use of electronic devices during takeoff and landing because "they empower people to stay informed and connected with friends and family, and they enable both large and small businesses to be more productive and efficient, helping drive economic growth and boost U.S. competitiveness."

Source: The New York Times



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Idiots
By Master Kenobi (blog) on 12/31/2012 1:36:44 PM , Rating: 5
The FAA has been riding this train for a long time and will continue to do so until someone with a clue rises to power and ends the idiocy. The current rules on electronics are just a reflection of "we don't want to test electronics, or get with the FCC to mandate a standard that can be checked for as airline approved". Sooner or later the old timers will either be fired (this is the government so thats highly unlikely) or simply retire. Once these fools are out, perhaps someone a few years younger will be less afraid of the modern world.

In the meantime, privately owned & operated airplanes worldwide have been enjoying shit tons of in flight wireless electronics for years. It's good to have the $$.




RE: Idiots
By topkill on 12/31/2012 2:06:10 PM , Rating: 2
I think the proper term here is "idiocracy" here

:-)


RE: Idiots
By jeepga on 12/31/2012 2:15:55 PM , Rating: 5
There's another aspect to it. By forbidding electronics it makes it easy to see if someone is doing something that would be disastrous at take-off or landing. I fly often and the take-off and landing ban of electronics is annoying, but nothing more.

A testing system wouldn't help. Who's going to check it? Do we forbid all electronics that aren't tested, or do the flight attendants need to check everyone's electronics before giving them a sticker to indicate they are approved to use them? It's not manageable.


RE: Idiots
By mcnabney on 1/2/2013 9:27:56 AM , Rating: 2
The testing is never going to find a 'bad' device. Only a CB/HAM radio is going to emit enough EM to actually be any kind of risk on an airplane. Neither of those are battery powered or personally portable/usable. Electronic devices (which are generally low-power) just don't emit enough.


RE: Idiots
By BillyBatson on 12/31/2012 2:42:30 PM , Rating: 1
Yups and as a former US Air Force jet engine mechanic on very high end helicopters and aircraft I can vouch that in my entire time in service not one incident ever occurred because someone has a cellphone on or in use. No one ever told us to put our phones away lol. During test flights we would sit in a trunk 8-10 people near the helicopter on the ground which would be running tests in case something went wrong we would jump out the trunk and go service the aircraft. What would we do for hours on the truck? Every single one of us on our phones parked next to the running aircraft. This is with communications, navigation, and other top secret systems all running, no issues.
The FCC is just too lazy and cheap to update this archaic rule


RE: Idiots
By Piiman on 12/31/2012 3:14:34 PM , Rating: 2
Why did hey make you sit in the Trunk :-)


RE: Idiots
By sorry dog on 12/31/2012 3:18:09 PM , Rating: 2
quote:
The FCC is just too lazy and cheap to update this archaic rule


Dontcha mean the FAA?

I think the rule is partially because of capacity interruption that can be caused by cell phone trying to communicated with 6 towers that it now has line of sight of since it's 10,000+ feet in the air. However, that affects cell providers more than anybody else, so it doesn't make sense that the FCC would say something against the rule....so I dunno...


RE: Idiots
By Piiman on 12/31/2012 3:26:14 PM , Rating: 2
But you're not @ 10,000 feet at takeoff or landing. And its not like these signals go way just because your phone is off.


RE: Idiots
By Telomar on 12/31/2012 4:58:05 PM , Rating: 4
Military aircraft and helicopters both use shielded electronic systems. I'm still not of the belief that it makes a difference on commercial aircraft but you'd certainly not see an effect on military systems.


RE: Idiots
By mcnabney on 1/2/2013 9:29:40 AM , Rating: 2
Military aircraft are more than 'shielded'. Commercial aircraft are shielded. The military can survive the EMP from a nuclear weapon.


RE: Idiots
By HoosierEngineer5 on 1/1/2013 1:04:32 PM , Rating: 1
I am glad you have the expertise to be able to determine that faulted/out of tolerance commercial-quality equipment won't interfere with cockpit communications, or affect radio navigation. Perhaps you can send your analysis to the FAA and clear it up for all time?

Sorry for the attitude, but nobody ever thinks about these things.


RE: Idiots
By mcnabney on 1/2/2013 9:43:55 AM , Rating: 2
I actually do. And the idea is laughable - even for devices that broadcast.

First, the antennas on commercial aircraft are on the outside of the plane - usually the wings. So the signal is going to have to penetrate the hull and travel a fair distance to even begin to have a chance to be disruptive.

Second, aviation uses specific set-aside spectrum for communications which are highly isolated from the spectrum reserved for wifi and commercial wireless signals. That means that the only thing an airplanes antenna will be sensitive to is 3rd/4th/5th order resonance frequencies.

Third, these devices are low-powered and not adjacent - so Inverse-Square is going to reduce any signal to background static by the time it gets there.

It just isn't possible. It would be like FM radio from New York interfering with VHF TV from Chicago. It just isn't going to happen.


RE: Idiots
By JediJeb on 1/2/2013 1:26:20 PM , Rating: 2
What about the buzzing I hear in my speakers every time I have a call coming in? Could that type of interference bleed into some of the electrical cabling running through the plane?


RE: Idiots
By jdownard on 1/2/2013 10:33:55 AM , Rating: 2
The problem here is not necessarily cell phones, tablets, or e-readers. The problem is that there are types of handheld, battery operated devices that could possibly be used to interfere with the electronic signals in an aircraft (think FM radio jammer). Likewise, they could also transmit relatively low power signals on frequencies that correspond to approach radios or communication radios, confusing the flight computer or disrupting communication at a critical time. These devices could be manufactured to resemble cell phones, tablets, and e-readers. In a plane with 300+ passengers, how can you possibly expect the flight crew to identify the differences? Not allowing the use of any device during the most critcal phases of flight (take-off and landing) is a minor annoyance at best and could help the flight crew identify anybody attempting to use such a device.


RE: Idiots
By Rukkian on 1/2/2013 10:49:18 AM , Rating: 2
If somebody could make something like that and wanted to purposely cause issues, they already could. They would not not use the device just because the flight attendent told them to turn it off.


RE: Idiots
By jdownard on 1/2/2013 11:28:05 AM , Rating: 2
In order for such a device to be effective, it would have to be activated during take-off or landing. If it was on beforehand it would be detected and alternate protocols initiated. In order for it to be activated somebody would need to have access to it, and likely pull it out, to switch it on. If nobody else on the plane is using anything and one person pulls out a device, and then something strange happens to the plane, then it is possible that the flight crew or one of the passengers would put together somebody activating a device and the plane issue as being related. On the other hand, if all 300 people on the plane have some kind of handheld device out and something happened there would be no way for the crew or passengers to identify the cause.


RE: Idiots
By Rukkian on 1/2/2013 11:46:33 AM , Rating: 2
I can attest that on any given flight several people never put away their electronics, and just hide them. If it were disquised close enough to a cell phone, that could already happen.

Basically you are saying that a terrorist will not take down the plane cause somebody told them not to. I guess we should have tried on on 9/11. Maybe if they just told them not to hijack the planes, they would have sat down and stopped the attack.

While I have no problem with the ban, your argument makes no sense to me at all.


RE: Idiots
By 91TTZ on 1/2/2013 11:44:02 AM , Rating: 1
Your post reeks of cluelessness. You make it sound like they're just old and afraid of technology which isn't the case.

I don't think that this is really what it's about. It's really about people paying attention. When the airline crew is trying to explain what to do in case of an emergency, you don't want people ignoring them while they play on their iPad.

quote:
In the meantime, privately owned & operated airplanes worldwide have been enjoying shit tons of in flight wireless electronics for years. It's good to have the $$.


The major airlines also have in flight wireless. It's just deactivated during takeoff and landing.


wrong subject in title
By MadMan007 on 12/31/2012 3:19:24 PM , Rating: 2
It should be 'stupid people harm people' not 'rules harm people.' Someone punching someone else is not the FAA's fault...it's the person's fault for punching someone else, and the device users fault for not following rules, even if they are misguided.

I read this article expecting to read something about not being able to communicate causing real harm, but instead it's this blame game crap for whiney people who can't go without their electronic crack for an hour.




RE: wrong subject in title
By Piiman on 12/31/2012 3:30:01 PM , Rating: 1
Well its the FAA rules that made this old guy think a cell phone would down his plane. Meanwhile the pilots have their iPads on watching prone. oh well


RE: wrong subject in title
By MadMan007 on 12/31/2012 4:51:11 PM , Rating: 2
He could have done something other than punch the other passenger though. 'Rules don't punch people, people punch people.'


RE: wrong subject in title
By inaphasia on 12/31/2012 10:59:26 PM , Rating: 2
Only if you know for a fact that the guy wasn't truly scared. Scared people usually just raise their voice but can easily become violent too.


RE: wrong subject in title
By Fritzr on 12/31/2012 11:46:54 PM , Rating: 2
Also the passengers were not arrested for failing to turn devices off. They were arrested for failing to follow crew directions .

When the crew tells a passenger to do something and the passenger refuses, that is a crime. The fact that the two mentioned failed to turn off electronics is irrelevant, the actual crime was failure to follow directions. (in this case, a reminder of flight safety regulations)


By groovieg on 12/31/2012 5:51:11 PM , Rating: 2
Instead of spouting off "I left my phone on during a flight and it didn't crash, therefore it is safe", how about doing a little research into what is really at issue. It's a bit out of date, but I read this article when it first came out and I think it provides good information on the subject. http://spectrum.ieee.org/aerospace/aviation/unsafe...




By Master Kenobi (blog) on 12/31/2012 9:47:31 PM , Rating: 2
Unfortunately the information is dated and doesn't provide information on the exact devices. Modern consumer electronics are low power and emit low EM signatures. Now if someone were to bring in say a Cell Jammer, I wouldn't put it beyond reason for that device to cause a problem, largely because a Cell Jammer emits a VERY powerful EM signal designed to disrupt EM signals of nearby devices.


By geddarkstorm on 1/1/2013 1:54:17 AM , Rating: 3
I guess the worry is if you have 120-200 people all using their devices at once, the aggregate EM interference would start to become a problem. Surely no one cell phone could be trouble, but a hundred in a cramped space?

I doubt it, but it is a pertinent question. I don't think the FAA needs to look at every device ever, but if they could take devices with the most powerful radios and simulate every passenger having one, for a absolute unrealistic worst case, that should be a sufficient test to put this issue to bed.


By Master Kenobi (blog) on 1/2/2013 4:45:37 PM , Rating: 2
Don't mix basic mathematics with EM science. Having a large saturation of low power EM devices on specific bands is not the same as having a single higher power device in the same or another EM band. The only issues you might encounter would be with devices that operate right next to bands utilized by the aircraft itself. The "bleed over" effect that might happen depending on how well made the device's transciever is would be greatest point of concern.


BS
By Piiman on 12/31/2012 3:11:51 PM , Rating: 2
"In order for the FAA to approve the use of e-readers and tablets during takeoff and landing, each kind of device needs to be tested. For example, an iPad cannot be tested alone; the iPad 2 and the new iPad must be tested as well"

Total Bull. all they have to test is if the singles ,3g,4g or wifi cause problems. It doesn't matter the device.




RE: BS
By V-Money on 12/31/2012 5:00:06 PM , Rating: 2
That would be a good way to improve marketing though, play on their stupidity. A company could pay for the tests of "(insert company's name here)" devices and be the only approved devices allowed on commercial flights. All of the other companies would quickly follow suit, but not before marketing can use it for a positive spin. They can even place a stupid symbol on the device showing that it's an approved device.

It would be a colossal waste of money (which we would all pay for eventually, but people are too stupid to realize that), but what isn't nowadays. I figure I'll volunteer to run this project into the ground using the most amount of resources while accomplishing the least amount. Once I get paid millions for my incompetence I'll go apply to head HP and finish the slow, painful death of a once iconic company. Who says people don't dream anymore.


RE: BS
By JediJeb on 1/2/2013 2:09:21 PM , Rating: 2
If all the companies hold to using the exact same shielding of the electronics and the exact same signal strength and the exact same amount of allowed variance in their signals then yes you could test based on protocol. But are the antenna the same for an iPad and Kindle? Same shielding, same power output? That is why the FAA would test them all separately.


Stuff Happens
By drlumen on 12/31/2012 6:27:36 PM , Rating: 2
A couple of things I have experienced with cell phones and interference. I'm not going to pretend to know how it happened but to say it happened.

About 7:00AM one morning I'm up getting coffee and the clock radio in the bedroom starts emitting these really loud screeching tones. The radio was off and was not in 'alarm'. Startled I went into the bedroom just as it was ending. No other issues but my cell was next to the radio.

Capturing video in an editing bay one day and in the captured video I hear the same set of tones as heard previously from the clock radio. Fainter but still there.

While on a landline one day, surprise, surprise the same tones. The only common denominator was that a cell phone was present (different cell phones over this time frame but the same set of tones). Since these occurrences I hear these tones in various places at various times.

So, is this interference enough to take down a plane? I doubt it. Could it be enough of an issue in the few seconds at take-off and landing? Very possible. I would hope planes are more noise immune but why take the chance of an altitude indicator glitching or a horizon indicator doing a back flip?

With that said, I no longer allow cell phones in my editing bays because of possible unwanted noise. If the FAA wants to keep the rules for no electronics on in aircraft at take-off and landing I can certainly see the reason and don't have a problem with following those rules.




RE: Stuff Happens
By Camikazi on 12/31/2012 11:14:53 PM , Rating: 2
Chances are that you clock complies with Part 15 of the FCC rules, which states that it cannot give off any interference that might hinder another device but it will accept any interference from any device even if that interference causes undeseried results. Many consumer devices are like that but planes are set to stricter rules and are made to not accept interference (and their frequencies are restricted and never used by consumer devices anyway) and are shielded to be protected against it.


This whole issue is moot....
By rdhood on 1/2/2013 11:07:08 AM , Rating: 2
Look, most people with cell phones have them on all the time for the complete trip. In the last 10 years, I am sure that I am not the only person to have a phone turned on and in my pocket for the entire trip. No planes have fallen out of the sky.

Absolute power corrupts absolutely. Just ask the FAA.




RE: This whole issue is moot....
By menting on 1/2/2013 3:06:18 PM , Rating: 2
well, a lot more tests need to be conducted that's all I can say.
Sure most people have left their devices on during takeoff/landing, but there just isn't enough information out there saying if ~200 phones are on, whether it would cause an issue or not. Maybe it's not an issue for 5, 10, maybe even 50 phones, but who knows at 100, 200? Does network/frequency make a difference? Does model of the plane make a difference? Nobody can say for sure right now.

Maybe they should conduct a few tests with planes full of turned on cell phones (like tens of thousands), and measure interference to get a better answer.


Meh
By SatchBoogie1 on 12/31/2012 2:25:59 PM , Rating: 3
Whether electronics really do or don't interfere with the airplane I don't really care that I have to turn off my iPad at takeoff/landing. Maybe I am in the minority, but this remains a "meh" issue to me.




Too expensive to test?
By Newspapercrane on 12/31/2012 1:32:33 PM , Rating: 2
If it's too expensive to test all of the individual devices to make sure they're safe for use on a plane make a Certification system, and charge the device manufacturers. Make a list of devices which are allowed to be used. Eventually after you've tested enough devices they'll realize that none of them are an issue, they can remove the system. They won't, but that's another conversation I suppose.

Heck, they could even make it part of the new patent system that we're never going to get.

Meanwhile, if anyone tries to stop me from using my analog bag phone during takeoff and landing I'll club them with it.




lots of beaurocracy?
By chromal on 12/31/2012 3:20:31 PM , Rating: 2
I don't understand why the FAA can't specify what RF emissions are unacceptable and then leave it to the FCC to confirm compliance as part of the certification process they already perform on RF devices in the USA.




GA
By MamiyaOtaru on 12/31/2012 6:17:44 PM , Rating: 2
General Aviation is great cause I can be on my ipad the whole time. Never seen any ill effects :)




By SlyNine on 1/2/2013 2:25:45 AM , Rating: 2
This is about as dumb as forcing people to turn of their engines while fueling up their cars.




Missing the point?
By frogger27 on 1/2/2013 12:42:19 PM , Rating: 2
I don't know why the airlines continue to use the 'interfere' boondoggle about turning off electronic devices. It causes confusion and an unwillingness to follow the rules based on anecdotal evidence otherwise.
As it was explained to me, if anything happens to the plane, these electronic devices can become projectiles and injure the occupants. Nothing more.
As there is a greater likelihood of something going wrong during take-off and landing, 'please stow your projectiles'.
I think if they'd adhere to this line of reasoning more, they would get greater compliance and less grumbling about it.




By omgwtf8888 on 1/3/2013 3:44:01 PM , Rating: 2
With the sophistication of the GPS systems available in todays phones and electronics, could a terrorist use the compiled data to shoot down a plane. Aiming blindly at a plane is an incredibly hard task but having all of the flight information lessens that degree of difficulty. On a simpler note do you really want a plane full of people all having phone conversations. Citing 2 incidents of people acting poorly because they did not comply with regulations will seem like nothing once everyone is jabbering and telling each other to shut up. Until they invent the Maxwell Smart "Cone of Silence" i would rather not have phones on planes.




unqualified blog posters
By rgsaunders on 12/31/12, Rating: -1
RE: unqualified blog posters
By rgsaunders on 12/31/2012 2:59:05 PM , Rating: 2
should not be subject to - sorry about that


RE: unqualified blog posters
By sorry dog on 12/31/2012 3:20:30 PM , Rating: 2
can you be more specific about the incident?

If this happened on a flight at high altitude, there should be an FAA incident report on it.


RE: unqualified blog posters
By Fritzr on 12/31/2012 11:35:42 PM , Rating: 2
1) A battery operated device that emits a kW level signal is not likely to be in use by a passenger on an airliner simply due to size.

2) If an aircraft is unable to survive common consumer electronics, then accidents due to this cause should already be on record. Compliance is a lot less than 100% and the cabin crew will not catch everyone who fails to turn off personal electronics.

Yes, it is possible, with sufficient power, to jam even heavily shielded circuits, but an aircraft that cannot handle devices manufactured under FCC rules of the last 15 years will also experience problems from external devices on and around the airport. Especially mobile radios used for comms.


RE: unqualified blog posters
By Fujikoma on 12/31/2012 3:22:01 PM , Rating: 2
What caused this RFI emission you're making a claim about?
Planes fly through a lot of EMI and RFI... constantly. I'd bet it's even worse when approaching or taking off from a major city. I don't expect a plane to be hardened, but when an actual 'accident' occurs and it's found to be from a normal electronic device, then fix the other aircraft and live with it. I'd be more concerned about the airlines skimping on maintenance than I would cell phones, tablets and hand held games. I'd even be more concerned about pilot depression leading to suicide, since there are actual cases of pilots taking others with them (9-11 excluded).


RE: unqualified blog posters
By rgsaunders on 12/31/2012 5:31:04 PM , Rating: 2
The RFI source in that case was one of the aircraft systems, the HF radio antenna cable ground shield had corroded severely at the point where it entered the fin break at the vertical stab and forward for about 12 feet into the cabin area. I grant you this is of a different order of magnitude being as it was approx 1 kw of RF output, however this was also on an older aircraft with mostly analog systems, newer aircraft with digital systems have different issues of RFI/EMI vulnerabilities, I would rather give up my electronics toys during the landing and takeoff cycles than take a chance for no good reason.


RE: unqualified blog posters
By Piiman on 12/31/2012 3:23:37 PM , Rating: 2
How do you know that is what caused it?


RE: unqualified blog posters
By rgsaunders on 12/31/2012 5:35:06 PM , Rating: 2
I was in charge of the tech crew that found the problem and carried out the repair, and then carried out special inspections on the remainder of our fleet. This incident happened in the mid 80s on Canadian military aircraft.


RE: unqualified blog posters
By HostileEffect on 12/31/2012 4:54:24 PM , Rating: 2
I usually drop my phone between my legs or under one of those free blankets and keep on doing what I was doing with no ill effect. You should be more worried about pocket ECMs, GPS, cell, and wifi jammers, all of which can be bought online. Use is illegal but that never stopped anyone did it?


What a dumb ARSE story
By Beenthere on 12/31/12, Rating: -1
RE: What a dumb ARSE story
By Azethoth on 12/31/2012 2:54:09 PM , Rating: 2
You are ignorant of the facts. In the entire history of aviation a cell phone has never crashed a plane.

You may as well call for a ban on cell phone use at gas stations because:
1) Use cell phjone at gas station
2) ???
3) Explosion!

These are both urban legends that then found themselves written into law because of people like you that are light on Science and heavy on "omg if I swim right after lunch I will get cramps and die!"

Just in case: nobody has ever gotten a cramp after lunch while swimming. Even if you get a cramp you then just get out of the pool. Drowning is not necessary.


RE: What a dumb ARSE story
By makken on 12/31/2012 4:03:22 PM , Rating: 2
Regardless of whether or not electronics have any effect on the plane's systems, I can understand why they wouldn't want you using a large/heavy, hard, unsecured, and expensive device during the most dangerous part of flight.


RE: What a dumb ARSE story
By rgsaunders on 12/31/2012 7:20:42 PM , Rating: 2
Your example of cellphone use at gas station is badly chosen, in many places cellphone use is prohibited while at the gas pumps. This is a hangover from the old days of cellular when the old brick phones had mechanical relays which were a potential spark source. Although it may be a non-issue today with modern cells, you still find the warning sticker at the fuel pumps in many places. You might want to use a different example.


RE: What a dumb ARSE story
By bobsmith1492 on 12/31/2012 4:01:08 PM , Rating: 2
As a EE in consumer, medical, and automotive product design, I can say all devices sold must pass FCC radiated emissions and susceptibility to radiated emissions (i.e. CISPR 25 in automotive).

The limits are set up such that devices are allowed to radiate much lower levels than the minimum they are required to handle without adverse effects. I can only assume avionics systems must pass even more strict levels of radiated emissions susceptibility than automotive products, so I can't imagine any cell phone or tablet Wi-fi or cell signal is anywhere close to causing problems on an airplane.


RE: What a dumb ARSE story
By Jarhead on 1/1/2013 1:48:45 PM , Rating: 2
Ah, yes. But imagine just half the passengers all had their devices operating at the same time? Consider that.

Then, Avionics inside the aircraft are tested to different standards than those that the connect to the outside. It is common for High Energy RF testing to allow well over 40dB lower test levels for the electronics inside the airframe, due to the shielding of the airframe. This is power, so every 3 dB is 1/2 (or 2x depending on which way you are going). So lets say a source outside the airframe is 1,000 Watts- Swell the electronics that deal with the outside get tested with a 1,000W level. Allowing for the 40dB attenuation of the airframe, the source inside the airframe for the internal electronics would be exposed to less than 0.005 Watts to pass. Most of us know a cell phone emits much more than 0.005 Watts. Same thing goes for other signals outside the aiframe, they are greatly attenuated. However, the internal Avionics are usually tested at higher levels than 0,005W, as there are other even higher power devices that the aircraft will encounter. The levels also change depending on the band (frequency range).

Now for the Avionics, failure is given in several different descriptions. One is that the device under test will give no false or misleading information during the threat's emission. Great, that helps, since many threats are not present all the time, but just a momentary emission. Consider if you had 100 cell phones and tablets bleeping and blopping 4G, 3G, WiFi, Bluetooth constantly. Just because one or two devices in use by the aircrew (like pilots) don't cause an issue, imagine the effect of hundreds of devices throughout the airframe. Worse yet, imagine all those devices emitting inside a metal chamber, where all that signal is contained and reflected around (yes, there is some attenuation effects caused by the absorption of that energy by the humans in that space, but still...). Imagine your wiring running down the inside walls of that metal can, and how a good amount of it is actually un-shielded.

bobsmith1492- I have watched multiple times, several pieces of Avionics failing the testing for FAA certification, only to find out that one single cell phone was the source of the failure, and once the cell phone was turned off, the Avionics passed with flying colors, and have gone on to be FAA certified. Consider that the cabling used during testing is usually very short (few feet), what the effects would be if the wiring was many yards long, and what it might do. One test I watched them turn the Bluetooth of all things, off on a tech's phone, and all of a sudden the Avionics under test worked fine! And Bluetooth uses very low power levels. Go figure...


RE: What a dumb ARSE story
By ssj3gohan on 1/2/2013 5:51:10 AM , Rating: 2
This is a common fallacy - compounding many independent small sources into one big source. In reality this is almost the opposite of what happens. Cellular and other wireless technologies use many small sub-bands and more importantly time-sharing in channels to give each other room to communicate. If you have a plane full of 300 WCDMA modems at 100mW (or -20dBi), according to your concept that would result in a 30W, close-to 0dBi (i.e. mind-numbingly high power) interference source, but in reality all these devices are time-shared over something like 4 or 6 channels, so the maximum possible total transceiver power on at any moment is more likely to be half a watt. That, still, is another fallacy because many independent sources do not sum as they interfere (mostly destructively) with each other.

Both in terms of radio units (-dB, watts) and electromagnetic units (H, B-field) these are puny numbers, especially in light of what we're talking about: interference into wired systems. You need extremely high interference levels to perturb wired systems, especially industrial wired systems in airplanes.


RE: What a dumb ARSE story
By PaFromFL on 1/2/2013 8:35:01 AM , Rating: 2
Exactly! The FCC and FAA only need to calculate the worst-case increase in the noise floor and base their decision on that. I doubt that any system on any aircraft will be affected. If some unusual circumstance weakens aircraft communication links, the pilot could then command passengers to turn off all devices.

Note that a million people with portable electronics devices can crowd together in Times Square without catching fire or interfering with multiple TV show productions and news reporting.


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