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Comments on news posted 2013-03-25 08:41:04: The Federal Aviation Administration says they expect to weaken rules prohibiting the use of electronics in-flight before the end of the year. According to the New York Times, those new rules would not allow the use of cellphone voice calls in flight. ..

page: 1 · 2 · next


IowaCowboy
Iowa native
Premium
join:2010-10-16
Springfield, MA
kudos:1
Reviews:
·Verizon Broadban..
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Rules are off target

They seem to think that an old Game Boy (which does not receive or transmit signals) causes interference with navigation electronics.

While I can see banning cell phones (as they are transceivers) as a legitimate concern, banning kids toys that don't have transceivers in them goes towards being off target.


TBBroadband

join:2012-10-26
Fremont, OH

and many "game boys" do have transceivers in them. How do you think the PSP connects to the Internet??


me1212

join:2008-11-20
Pleasant Hill, MO

I think he is talking about the classic gameboy, not a psp which is very much not a gameboy.



IowaCowboy
Iowa native
Premium
join:2010-10-16
Springfield, MA
kudos:1

I had one of the original game boys. Nintendo did not add Internet connectivity until the DS line. I just bought a 3DS and I downloaded some games that I have not played since I was hospitalized in 1998.



Boricua
Premium
join:2002-01-26
Sacramuerto

1 recommendation

Took them long enough...

Flight attendants told people to turn off the electronic devices even if it's on airplane mode . They must not have read the memo stating when a device is in airplane mode, it is NOT transmitting anything since the wireless radio is turned off.
--
Illegal aliens have always been a problem in the United States. Ask any Indian. Robert Orben



Probitas

@teksavvy.com

trapped consumer

Why allow customers to use their own already paid for services (assuming the phone can reach that high up) when they can trap you into using theirs for high prices by claiming it's a 'safety issue'.

Fact is, those signals are flying through the air regardless, as phone signals are always traveling around the planet, so that even if no one on the plane had one, it would still be encountering those signals, and as far as I know the plane is not shielded from those signals, or you would not be able to use their own phone service to make a call.



keyboards

join:2001-02-14
Doylestown, PA

All electronics are "transmitters"

The concern (though not necessarily valid) is that any piece of electronics (whether it has a "transceiver" or not) has the potential to create RF interference from radiation (EMI - ElectroMagnetic Interference) caused by its own internal clocking.

This has been mostly shown to not be a problem with most modern electronics as FCC Class B (residential use) certification pretty much assures that the emissions won't interfere with outside electronics. Used to be a much bigger problem with older, more poorly shielded devices.
--
REMEMBER: Stupidity should be painful !!


coma9

join:2013-02-05
United State
reply to TBBroadband

Re: Rules are off target

said by TBBroadband:

and many "game boys" do have transceivers in them. How do you think the PSP connects to the Internet??

Didn't know that a PSP was a GameBoy... GameBoy was it's own product line made by Nintendo in the late 1990's and early 2000's. The original GameBoy was a large bulky device, that didn't even have color, let alone any network connectivity. It was unable to send or receive signals of any kind. The GameBoy Color had an IR port, and a data transfer cable, but still no network connectivity.

rradina

join:2000-08-08
Chesterfield, MO

Where's the friggin' innovation?

How hard would it be for a phone, tablet, laptop or any mobile device (i.e. GameBoy, PSP, iPod, e-reader, whatever) to work with the aircraft and automatically disable harmful features during certain flight events?

Just last week we read about Apple's patent that attempts to change the orientation of the phone when dropped so that it lands in a manner least likely to do damage. We have a patent for that but we cannot figure out a way for the aircraft and mobile devices to work together rather than put flight attendants in the unenviable position of running an EMI Gestapo?


rradina

join:2000-08-08
Chesterfield, MO
reply to Probitas

Re: trapped consumer

Agreed but those signals may not be as potent when coming from a cell tower at least six miles away (considering cruising altitude is generally ~30,000 feet or more) vs. 100 phones that are on the same plane.


Crookshanks

join:2008-02-04
Binghamton, NY

1 edit

it really has nothing to do with the aircraft....

.... it has everything to do with the design of the cellular network. From 35,000 feet your phone is going to "hear" dozens of base stations. Seven miles is nothing for a cell phone radio, particularly with a clear line of sight.

Two issues here:

1) Phones and the cellular network were not designed for the number of rapid hand offs that will occur at 500 knots. Recall that on 9/11 people were able to make 911 calls from the airplanes but they were all dropped fairly quickly. These drops were failed handoffs, not a lack of signal.

2) From altitude, your phone will hear dozens of base stations. Conversely, all of those base stations will hear your phone. This has the effect of lowing the signal to noise ratio in the cellular network and making it that much harder for clients with low signal levels to maintain a connection to the network. The cellular network has to be very carefully designed to minimize this problem, which is hard enough under the best of circumstances. Trying to manage this problem with mobiles at 35,000 feet that are heard by dozens of different base stations is impossible.

Google 'near far problem' for some very interesting reading on this subject. It truly is amazing just how much engineering goes into making the cellular network function as well as it does. Base stations have to be very carefully located so they don't interfere with one another, particularly in those neighboring areas where coverage overlaps exist. Every single mobile is commanded to adjust its transmission power dozens of times per second while in an active call/data session. OFDM (LTE) networks actually broadcast at different power levels for each subchannel to mitigate interference in fringe areas/allow for successful handoffs.

Ponder all of this the next time someone tells you that bandwidth problems can be solved "simply" by adding more base stations, or when one of your NIMBY neighbors complains about a new tower going up because "They could just use that one over there."

Voice/data sessions _could_ be made to work by having a femto/pico cell on the aircraft. Then the mobiles could transmit at a very low power level and would not cause interference to clients on the ground. Of course, I'm sure the airlines would charge a hefty premium for this service, and frankly I'm not sure I want the self-important asshat sitting next to me screaming into his phone for the whole flight. Data is more easily provided with wi-fi than a femto/pico cell, so not much reason for it there.


patcat88

join:2002-04-05
Jamaica, NY
kudos:1
reply to keyboards

Re: All electronics are "transmitters"

said by keyboards:

This has been mostly shown to not be a problem with most modern electronics as FCC Class B (residential use) certification pretty much assures that the emissions won't interfere with outside electronics. Used to be a much bigger problem with older, more poorly shielded devices.

So a mw oven with the door switch bypassed and a satellite dish and I can knock planes out of the sky like fowl and a shotgun?

Terrorists must be really stupid to uses these instead of a 1000x cheaper and reusable mw oven

»www.youtube.com/watch?v=KatcZQrSgsg


Come on, any aircraft engineer who didn't RF shield the plane's circuit boards would be doing prison time right now.


Omega
Displaced Ohioan
Premium
join:2002-07-30
Denver, CO
reply to Crookshanks

Re: it really has nothing to do with the aircraft....

You missed the most important part. Allowing people to have voice conversations on their phone on a plane would be annoying as hell.
--
What smells like blue?


patcat88

join:2002-04-05
Jamaica, NY
kudos:1
reply to Crookshanks

said by Crookshanks:

2) From altitude, your phone will hear dozens of base stations. Conversely, all of those base stations will hear your phone. This has the effect of lowing the signal to noise ratio in the cellular network and making it that much harder for clients with low signal levels to maintain a connection to the network. The cellular network has to be very carefully designed to minimize this problem, which is hard enough under the best of circumstances. Trying to manage this problem with mobiles at 35,000 feet that are heard by dozens of different base stations is impossible.

Put 1 parabolic antenna at each tower pointing straight up into outer space, end of problem.

Crookshanks

join:2008-02-04
Binghamton, NY
reply to Omega

I covered that with the self-important asshat comment.


rradina

join:2000-08-08
Chesterfield, MO
reply to patcat88

Help me understand how that solves the problem. It might if the antenna and all aloft devices automatically use a different frequency. If not, how does a parabola stop the regular cell antennas from hearing airborne devices? Even if it was huge, in an attempt to block vertically transmitted signals from the tower's normal antennas, it wouldn't stop reflected signals.

If something like this is desired, it would be much more effective to use the same tower antennas and a different frequency when aloft. The greater range of airborne devices might mean fewer towers would need to be adapted and fewer hand offs. However, that would severely limit capacity and in heavily populated areas, there are a ton of planes with many thousands of passengers in the air.

Furthermore, unless the FCC frees up a ton of spectrum, no carrier is going to devote any such precious spectrum to airborne-only devices. They might if given a ridiculous amount of bandwidth at extremely high frequencies (5ghz, 10ghz) but at these frequencies, penetrating even a composite aircraft body would seriously reduce signal strength not to mention require more power. That would trash battery life. It might work if planes had built-in signal repeaters. However, we're talking about an industry that will eventually mag-stripe the lavatory, weigh the waste so they can charge by the ounce -- including the water you use to wash your hands -- and add a unit premium for solids! They aren't going to install free signal repeaters.


patcat88

join:2002-04-05
Jamaica, NY
kudos:1

2 edits

said by rradina:

Help me understand how that solves the problem. It might if the antenna and all aloft devices automatically use a different frequency. If not, how does a parabola stop the regular cell antennas from hearing airborne devices? Even if it was huge, in an attempt to block vertically transmitted signals from the tower's normal antennas, it wouldn't stop reflected signals.

Phone sees stronger sky facing antenna, not 90 degree weak edge of ground aimed sector antennas. Phone locks onto sky facing channel/psuedochannel (CDMA) antenna, reverse link power control lowers the phone's transmit power, end of problem. All cellphone networks have interference, the question is how much. The sky facing antennas do frequency reuse just like ground aimed ones.

»en.wikipedia.org/wiki/Frequency_···cy_reuse

The problem isn't new and its been solved years ago. Take a ferry or drive a car over a long causeway/viaduct in a heavily populated metro area, with skyscrapers. Your phone will see 100s of towers. Does your phone drop or loose service while on the ferry or driving on the suspension bridge? NO.

The BSS can figure out when a phone is seeing too many towers, and steer all the phones in the bay (water) to a particular channel/tower that is reserved for open water bay phones. A phone can not switch towers without the tower's/network's permission.

»en.wikipedia.org/wiki/Radio_reso···nagement

rradina

join:2000-08-08
Chesterfield, MO

If this works, why haven't they done this? Every aircraft has several (possibly half the phones) accidentally or purposely left on during flight. Theoretically, these phones are transmitting at maximum power trying to find cell towers. Wouldn't that unnecessarily cause a lot of interference for ground-based traffic? Wouldn't the industry want to solve it the way you suggested?



alg
Passionately apathetic
Premium
join:2001-04-10
Houston, TX
kudos:3

Flight mode

As somebody who flies a lot and who likes the view out the window I'd be happy with just being able to openly take pictures during takeoff and landing without having the FA jump all over me over the PA.
--
This is the way the world ends
Not with a bang but a whimper.


Crookshanks

join:2008-02-04
Binghamton, NY

2 edits
reply to patcat88

Re: it really has nothing to do with the aircraft....

said by patcat88:

Take a ferry or drive a car over a long causeway/viaduct in a heavily populated metro area, with skyscrapers. Your phone will see 100s of towers.

Urban areas have very few macro cells that provide long range coverage. Micro and pico cells are far more common. The macro cells are used to service fast moving (e.g., phones in cars, on the train, etc.) or more distant mobiles, while the rest are directed to micro/pico cells that serve a much smaller footprint. In your scenario the phone would not hear more than a handful of towers, as it would quickly move out of range of the micro and pico cells.

said by patcat88:

A phone can not switch towers without the tower's/network's permission.

Cellular networks are divided into paging areas. Your mobile does not notify the network when it switches to a different base station within the same paging area, it only tells the network when it moves into a new paging area. The cellular network has no idea which specific base station an idle mobile is listening to, and it may well be listening to more than one at a time in a CDMA network. Asking for permission for every single base station hand off while idle would consume a lot of power.

The network can command a mobile to switch channels or base stations, but the mobile does not have to request permission to move between base stations while idle. An idle mobile doesn't even have its receiver turned on a majority of the time, it wakes up every so often to check for pages, then goes back to sleep. This is another power saving feature, and one of the reasons why LTE can be such a battery hog -- getting low latency requires keeping the receiver on more than older technologies.

Crookshanks

join:2008-02-04
Binghamton, NY
reply to rradina

Phones don't transmit while looking for towers, they only transmit during initial registration and when moving between paging areas. Short bursts of communications don't have much of an impact on the overall signal-to-noise ratio of the network. The problem only becomes apparent when the phone is transmitting with a full duty cycle, e.g., while in a call, or engaged in a large data upload.

As for why they don't do it the way he wants, because it would be a foolish waste of money? Retrofitting every single base station in the country and sacrificing precious spectrum to service mobiles on airlines makes no sense. Pico/femtocells on the aircraft would be the way to solve this "problem", if the industry and airlines were so inclined.


Rekrul

join:2007-04-21
Milford, CT
reply to Omega

said by Omega:

You missed the most important part. Allowing people to have voice conversations on their phone on a plane would be annoying as hell.

How would that be any more annoying than passengers talking to each other?

Rekrul

join:2007-04-21
Milford, CT
reply to TBBroadband

Re: Rules are off target

said by TBBroadband:

and many "game boys" do have transceivers in them. How do you think the PSP connects to the Internet??

If electronic devices really posed a danger to planes, the TSA wouldn't let you carry them on board.


TSprky

@verizon.net
reply to Rekrul

Re: it really has nothing to do with the aircraft....

said by Rekrul:

said by Omega:

You missed the most important part. Allowing people to have voice conversations on their phone on a plane would be annoying as hell.

How would that be any more annoying than passengers talking to each other?

Because people talking on the phone use their "phone voice".

jc100

join:2002-04-10
reply to coma9

Re: Rules are off target

Try a lot earlier. The original game boy had a dot matrix screen and I owned one in 1989. I won it for selling boy scout popcorn. The sucker still works 23+ years later too. Take that well made toys of the bygone era.


jc100

join:2002-04-10
reply to IowaCowboy

The original game boys came out in 1989. Rock solid, dot matrix toys. Mine still works albeit not the greatest, but functions. I dare you find any toy made today lasting that long!

Cheap crap made to break.

Per the FAA relaxing rules, please by god don't allow cell phone use in the planes. We all now from Mythbusters that phones DO NOT interfere with guidance systems. However, I DO NOT want to listen to some loud mouth yapping away on a few hour flight. It's bad enough in public.



Vchat20
Landing is the REAL challenge
Premium
join:2003-09-16
Columbus, OH

Good luck actually making a call at 30k+ feet in the air. It just won't happen. Unless the airline deliberately puts picocells in the aircraft to accomplish it. Just for shits and giggles, try turning off airplane mode inflight and see what happens to your signal. 1 bar or less and constantly going in and out of service. Have tried myself. Sometimes don't even get a time update from the cell towers when traversing time zones.
--
I swear, some people should have pace-makers installed to free up the resources. Breathing and heart beat taxes their whole system, all of their brain cells wasted on life support.-two bit brains, and the second bit is wasted on parity! ~head_spaz


ptbarnett

join:2002-09-30
Lewisville, TX

1 edit
reply to patcat88

Re: All electronics are "transmitters"

said by patcat88:

Come on, any aircraft engineer who didn't RF shield the plane's circuit boards would be doing prison time right now.

Wow, there are a lot of people who think they are RF engineers today.

The problem is not shielding of circuit boards. It's whether an errant transmission blocks reception by a navigation radio.

All digital electronic devices emit RF. A digital device has an internal clock, that may be anything from 1 MHz to 1 GHz or higher. That generates RF, albeit at a much lower level than devices designed to transmit. To quote Montgomery Scott: you can't change the laws of physics.

In addition, even if you aren't transmitting, a RECEIVER can transmit RF. Look up "superheterodyne receiver" on Wikipedia, and read the section on local oscillator radiation.

You can design the device to shield RF emissions. But, it is difficult to completely seal it unless it is a metal box with no buttons, plugs, etc. The best you can do is reduce it as low as possible. That what FCC class B certification is about: it has to be below a certain level, but that level is not zero.

Oh, and it gets worse: two transmitters in close proximity on different frequencies can generate a transmission on a THIRD frequency. This is known as inter-modulation. Since modern electronic devices change their clock frequencies regularly (mostly to conserve power when they are idle), you can see how it's really hard to predict what will happen when a bunch of them are in close proximity to each other.

However, that's only the transmission side of the issue. The next inevitable question is: why don't the aircraft receivers reject these unwanted signals? Aircraft navigation and communications use several different frequency bands. On any given flight, the pilots will be switching frequencies many times. And depending on the phase of the flight, the signals being received may be relatively weak, and more susceptible to interference.

All it takes is for an electronic device to inadvertently transmit on the same frequency an aircraft receiver is receiving, and you'll have interference. Some of the navigation radios work by measuring the phase of a received signal, so it doesn't take much to mess them up. Once again, it is the laws of physics. A very low power transmitter on the plane can block receipt of a signal from a much more powerful transmitter far away.

Fortunately, the instruments usually indicate when there is interference, and pilots are trained to switch to alternate means of navigation. So, one outage is not going to cause an accident. But, accidents are rarely caused by a single event -- it's a chain of events. A communication or radio outage caused by interference can be a distraction, and become the first or subsequent event in a chain that leads to an accident.

However, after writing all that, I agree with a previous poster: modern electronic devices are mostly well-shielded, and unlikely to emit enough RF to block aircraft radio reception unless they are damaged. But, it hasn't always been like that, even as recently as the past decade.

patcat88

join:2002-04-05
Jamaica, NY
kudos:1

said by ptbarnett:

The problem is not shielding of circuit boards. It's whether an errant transmission blocks reception by a navigation radio.
........................
You can design the device to shield RF emissions. But, it is difficult to completely seal it unless it is a metal box with no buttons, plugs, etc. The best you can do is reduce it as low as possible. That what FCC class B certification is about: it has to be below a certain level, but that level is not zero.
...............................
However, that's only the transmission side of the issue. The next inevitable question is: why don't the aircraft receivers reject these unwanted signals? Aircraft navigation and communications use several different frequency bands. On any given flight, the pilots will be switching frequencies many times. And depending on the phase of the flight, the signals being received may be relatively weak, and more susceptible to interference.

All it takes is for an electronic device to inadvertently transmit on the same frequency an aircraft receiver is receiving, and you'll have interference. Some of the navigation radios work by measuring the phase of a received signal, so it doesn't take much to mess them up. Once again, it is the laws of physics. A very low power transmitter on the plane can block receipt of a signal from a much more powerful transmitter far away.

Ever heard of a solar storm? Planes dont fall out of the sky.

(b) Operation of an intentional, unintentional, or incidental radiator is subject to the conditions that no harmful interference is caused and that interference must be accepted that may be caused by the operation of an authorized radio station, by another intentional or unintentional radiator, by industrial, scientific and medical (ISM) equipment, or by an incidental radiator.

»www.law.cornell.edu/cfr/text/47/15.5

So the circuit boards on planes are not FCC certified?

said by ptbarnett:

r
Fortunately, the instruments usually indicate when there is interference, and pilots are trained to switch to alternate means of navigation.

The radio instruments do not fly the plane, nor will they make it go into a steep dive to the ground like in a cartoon. Inertia gyroscope doesn't use radio waves. Loosing radio instruments is like the street name on the road being covered, but you can still see the curve up ahead. You are right the instruments detect interference and lock themselves out.

said by ptbarnett:

So, one outage is not going to cause an accident. But, accidents are rarely caused by a single event -- it's a chain of events. A communication or radio outage caused by interference can be a distraction, and become the first or subsequent event in a chain that leads to an accident.

That is a sign of bad training or social problems at the airline.

ptbarnett

join:2002-09-30
Lewisville, TX

said by patcat88:

Ever heard of a solar storm? Planes dont fall out of the sky.

A solar storm can cause interference with the radio communication and navigation, especially in the high-frequency bands. The VHF bands used by aircraft are not immune, but less so than HF. Satellites are more vulnerable than anything, because they aren't protected by the Earth's magnetic field. But, the nice thing about radio interference from solar storms is that it can be forecasted. Airplanes can, and have modified procedures in advance to compensate for the expected interference.

However, did I ever write that planes would fall out of the sky? Rather than building a strawman argument, maybe you should read what I wrote, rather than what you think you can argue against?

said by patcat88:

So the circuit boards on planes are not FCC certified?

The US code that you cited says that the device must accept interference without damage. It doesn't say that it must function properly during the interference. An example would be your Wi-Fi connection or Bluetooth headset: Have you ever lost a connection or heard a crackling noise when the microwave oven was running in your kitchen? That's interference. But, unless you put the device IN your microwave, it resumed functioning after the microwave shut off.

The electronic devices on civil planes (other than experimentals) in the US are TSO certified, which is far more stringent than any FCC certification. The TSO standard relevant to this situation is rejection of interference from an ADJACENT frequency. That is specified in terms of both frequency deviation and power level, as a very strong signal on an adjacent frequency can also "blank" a receiver. Again, it's laws of physics.

said by patcat88:

The radio instruments do not fly the plane, nor will they make it go into a steep dive to the ground like in a cartoon.

Actually, in a Cat III approach, the autopilot is coupled to the navigation radios, and does fly the plane. However, the pilots monitor the landing and will command a missed approach if anything appears amiss.

said by patcat88:

That is a sign of bad training or social problems at the airline.

No, it's the conclusion of many accident investigations. Pilot training, air traffic control procedures, and equipment design all have layers of redundancy to prevent a single failure from leading to an accident. Removing or circumventing a single layer doesn't necessarily cause a crash, but may increase the probability of one in the event all other layers fail.