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Despite the U.S. ban on cellular calls on airplanes, air travelers have a hard time keeping their hands off their mobiles and often make calls during critical stages of the flight such as final approach, according to a research team from Carnegie Mellon University.
As part of the study, released Monday, the research team filled their hand luggage with a broadband antenna and spectrum analyzer and boarded random airplanes crossing the Northeast United States. Picking up signals from cell phone calls onboard, they found that an average of one to four calls are made on every U.S. commercial flight.
"These devices can disrupt normal operation of key cockpit instruments, especially Global Positioning System receivers, which are increasingly vital for safe landings," Bill Strauss, an expert in aircraft electromagnetic compatibility at the Naval Air Warfare Center in Patuxent River, Md., and one of the researchers who conducted the study, said in a statement.
Strauss said risks are caused by radio emissions from cellular calls that are higher than previously believed.
The tests were aimed primarily at tracking emissions from cell phones, but they showed that other electronic equipment used on planes, such as laptops and game devices, also send out potentially harmful signals.
The report adds to the debate that was generated last June after the Federal Communications Commission proposed lifting its 1991 cell phone ban, letting passengers use their phones and other electronic devices while flying.
The ban was originally put in place to prohibit calls aloft from interfering with cell phone conversations on the ground and planes' radio communications, a risk that the FCC claimed might be outdated thanks to technical developments.
But lifting the ban is a bad idea, according to the Carnegie Mellon researchers. They recommended instead designing special tools for flight crews to track the use of electronic devices during critical stages of the flight.
The FCC proposal at the time elicited negative reactions from the Department of Homeland Security and the FBI, which expressed concerns that wiretapping guidelines would not be met.
The FCC said its move was triggered by the public's wish to make calls while flying, but not all air travelers agree. A National Consumers League survey last year showed that most passengers want to keep the ban in place, to avoid annoyance from yapping seat neighbors and trouble hearing emergency announcements.
The ban could be lifted as early as the end of this year.
See more CNET content tagged:
ban, flight, passenger, call, plane
Thanks for listening.
more than we ever imagined. oooohhh... scary. Now why did we
imagine they were not as dangerous? Oh that's right, because
not a single aviation accident has been related to cell phone
usage in the air! but wait, it's REALY REALLY dangerous!! People
are doing it 1-4 times on every flight, and not a single incident,
but it's REALLY REALLY dangerous.
For Pete's sake, stop paying anal-ists to produce findings that
are agenda driven and complete self contradictory.
Pfff...!!!
report incidents because it reflects negatively on their bottom line
and their job security. Airlines have PR people that control what
gets released and cellphone companies are probably lobbying for
the lift on the ban. If it's that important to be on the phone, the
satellite phone is available to you.
grrrrrrrrrr
partially caused by personal electronics interference, but not
attributed because it could not be conclusively determined. That
doesn't mean it didn't happen.... Also, pilots frequently report
malfunctioning instrumentation during critical flight operations
that likely are caused by personal electronics. Just because
skilled pilots prevent a disaster doesn't mean the electronics are
safe and are not causing problems. I'm a senior accident analyst
at a USA National Laboratory and track this problem rather
closely... I really hate to see such a clueless posting by a Mac
user, as I use only Macs and other Unix computers in my work...
I forsee new "road rage" incidents by passengers forced to sit next to someone on the phone for hours if they lift the ban. And the sad thing will be that the one who was responsible for these incidents will be "innocent" when the air marshals have to subdue the outraged.
just a prediction...
aware that not only is it a nuisance or that you are providing
everyone around you with entertainment but that it is
dangerous.
Once on an airbus, we were taxing out and the captain calls and
asked is anyone using their phone. The plane just recieved a
impact alarm. Meaning that the plane had given us a warning
that we had just been hit by another plane. A cellphone can
trick our sensors into thinking that there's been an impact. The
electromagnetic fields can mimic another foreign entity. The
captain certain that there wasn't anything near us on the tarmac
continued to taxi out on our flight. We didn't follow up on the
warning we just went on.
One plane from Air Alaska continued on after it's fuselage had
been punctured by a baggage handler. Did the captain from
that flight think it was a cellphone interference as well?
Midflight, the Air Alaska plane experienced a decompression.
Luckily, they landed safely but still. It's unnerving to think that
one day that false alarm may not be false.
aware that not only is it a nuisance or that you are providing
everyone around you with entertainment but that it is
dangerous.
Once on an airbus, we were taxing out and the captain calls and
asked is anyone using their phone. The plane just recieved a
impact alarm. Meaning that the plane had given us a warning
that we had just been hit by another plane. A cellphone can
trick our sensors into thinking that there's been an impact. The
electromagnetic fields can mimic another foreign entity. The
captain certain that there wasn't anything near us on the tarmac
continued to taxi out on our flight. We didn't follow up on the
warning we just went on.
One plane from Air Alaska continued on after it's fuselage had
been punctured by a baggage handler. Did the captain from
that flight think it was a cellphone interference as well?
Midflight, the Air Alaska plane experienced a decompression.
Luckily, they landed safely but still. It's unnerving to think that
one day that false alarm may not be false.
aware that not only is it a nuisance or that you are providing
everyone around you with entertainment but that it is
dangerous.
Once on an airbus, we were taxing out and the captain calls and
asked is anyone using their phone. The plane just recieved a
impact alarm. Meaning that the plane had given us a warning
that we had just been hit by another plane. A cellphone can
trick our sensors into thinking that there's been an impact. The
electromagnetic fields can mimic another foreign entity. The
captain certain that there wasn't anything near us on the tarmac
continued to taxi out on our flight. We didn't follow up on the
warning we just went on.
One plane from Air Alaska continued on after it's fuselage had
been punctured by a baggage handler. Did the captain from
that flight think it was a cellphone interference as well?
Midflight, the Air Alaska plane experienced a decompression.
Luckily, they landed safely but still. It's unnerving to think that
one day that false alarm may not be false.
:D
ensuring devices don't interfere is the job of a whole government agency - the FCC
At least you can find peace and quiet in a library still. If someone forgets to turn off their cell and it rings, their dead.
Is there any truth in any of these studies other than the self-interest of phone service providers on airplanes?
from outside the plane don't penetrate inside very well. By the
same token, cell phone signals inside the plane don't penetrate
outside very well, so the phone jacks up the output power to
keep contact with the tower. The strong signal is bouncing
around inside the plane, being picked up by the onboard wiring
and conducted to the instrumentation. Yes, there is lots of truth
in the studies. Proposed inflight cell systems would have an
internal antenna which penetrates through the aircraft skin (like
the onboard phones now) with amplification of the signal
broadcast outside the aircraft skin which would help minimize
the power the cell phones put out inside the aircraft. Still, it's an
increased risk. How much additional risk are YOU willing to
accept when you fly just so people can jabber?
I'll have to ask my EE co-workers for her copy of IEEE Spectrum to find out the REAL story...
I am also cringing at the possibility of winding up sitting next to some blowhard who just cannot keep quiet, babbling on and making much ado about nothing. I think the rules should favor the non-phone-using passengers - if someone is being bothered, then the offender has to hang up, with no further discussion required (perhaps after something like a five minute minimum amount of call time for things like coordinating ground transportation, hotel reservations, etc. - i.e., reasonable and necessary communications).
As for the range of cell phones, the maximum distance between cell towers for continuous coverage is 6 ~ 12 miles, depending on the terrain, the electromagnetic environment, and the number of other cell phones competing for bandwidth. So, 20,000 ~ 40,000 feet (i.e., roughly 4 ~ 8 miles straight up) is well within the line-of-sight of cell transceivers on the ground (even taking into account slant angle due to aircraft altitude, the requirement for the signals to make it in and out of the aircraft via the windows, etc.). Note that the through-the-window comms is between tuned transmitter/receiver pairs - this requires much less signal strength than just random ground interference I referred to above. One of the biggest opponents to lifting the ban is the cell phone companies themselves, because a cloud of tens of thousands of phones criss-crossing the continent at a significant fraction of the speed of sound at any given time (there are about 30,000 commercial flights a day over the U.S., and assuming an average of 100 potential callers per airliner, that's in the neighborhood of three million potential calls going on within a ~ 20 hour day (within four time zones, plus Alaska's and Hawaii's). Unfortunately, the cell phone system is designed/optimized for mobile users moving at a maximum of about one-tenth of the speed of an airliner, so phones need to switch cell towers about once every minute or so, instead of once every ten minutes (and typically much longer, for stationary users). If three million calls a day are suddenly going on at the higher speed of mobility, the software in all of the cell tower/transceiver sites is probably going to have to be upgraded (the systems do predictive switching between sites as the signal strength of a given phone changes from one site to the next along the path of movement, and the current movement model optimizations will likely need to be extended for higher-speed subscribers). If you think there are times of the day around urban areas when you get dropped calls more often than others now, just wait until you're competing with all those fickle flying folks on the phone.
It's interesting to note that cell phones are technically allowed to be used on private aircraft that are not being flown under instrument flight rules (IFR), i.e., being flown under visual flight rules (VFR). I say "technically" because use of cell phones is specifically prohibited by the Federal Aviation Regulations (FARs) on any aircraft flying under IFR (which all commercial passenger aircraft are, even on bright, sunny days without a cloud in the sky), but not specifically prohibited (and therefore implicitly allowed) on aircraft flying under VFR. I did a search of the NTSB database for general aviation accidents involving any cell phone usage, and couldn't find any, but I may not have picked exactly the right key words for the search. I suspect that there have to have been at least some incidents where a cell phone (e.g., during taxiing, which can be very confusing, especially at night at an airport with multiple/crossing runways, where a pilot has never been).
Unless/until the cell phone ban is lifted, you have a very powerful weapon right in your seat armrest - the attendant call button. If someone is on the phone, using a computer, playing a game, playing a CD, or using any other restricted device during taxi, takeoff, descent or landing, ask them politely to turn it off, and if they don't, then press that call button and let the crew deal with it (including the air marshall, if necessary). They carry these convenient hand restraints that match any outfit and fit all sizes, and it really is hard to hold a cell phone while sitting on your hands that are pinned behind your back (much less initiate a call on it).
All the Best,
Joe Blow
shared and for taking the time to type it all out. Many thanks.
From a Senior Accident Analyst
Maybe someday cell makers will wake up and introduce a device/standard that forces cell phones to mute their ringers in hospitals, churches, movie theaters and conference rooms.
Shouldn't be hard!
But the safety issue is just scare tactics.
No that is scary.
I guess we should wait until those things happen before doing something about it.
I travel 90K a year, if cell phone on plane are OK I am using my cell phone jammer.
the rest rooms.
Now you think the easy way is to have lines to a designated area aka phone booth?
Apparently you are too young to remember what it was like to fly before a good invention like cell fones invaded our lives with no place to hide.
Ahhhhh peace and quiet, to snooze, read a book, listen to some music or engage an amiable fellow psgr in idle chit chat.
I have heard for years that cell phones are dangerous but I have yet to see the case where anyone has shown any proof that they are dangerous. Where is the proof? the data?
Its starting to sound like one of those uban myths.
If there is a definative study from a credible source please post a segment or link here, I would love to see it. (<- sincere request, not sarcasm)
An article by the folks who actually did one of the studies. From
page 5 "Bill Strauss is an expert in aircraft electromagnetic
compatibility at the Naval Air Warfare Center"
From page 3 "there is a clear and present danger: cellphones can
render GPS instrument useless for landings."
From page 4 "we found 125 entries in the ASRS database that
reported PED interference. Of these, 77 were considered highly
correlated, based on the description of observed PED use and
interference occurrence. The reports included cases of critical
aircraft systems such as navigation and throttle settings being
affected."
"In one telling incident, a flight crew stated that a 30-degree
navigation error was immediately corrected after a passenger
turned off a DVD player and that the error reoccurred when the
curious crew asked the passenger to switch the player on again."
A 30 degree navigation error is clearly enough to potentially
make a bad-weather landing attempt non-recoverable...
Other than bodies on the ground (maybe your loved ones...),
how much more proof do any of you want?
You'd all better hope you never try to illegally use a cell phone
on an airplane within my view...
David
Sr. Accident Analyst
An article by the folks who actually did one of the studies. From
page 5 "Bill Strauss is an expert in aircraft electromagnetic
compatibility at the Naval Air Warfare Center"
From page 3 "there is a clear and present danger: cellphones can
render GPS instrument useless for landings."
From page 4 "we found 125 entries in the ASRS database that
reported PED interference. Of these, 77 were considered highly
correlated, based on the description of observed PED use and
interference occurrence. The reports included cases of critical
aircraft systems such as navigation and throttle settings being
affected."
"In one telling incident, a flight crew stated that a 30-degree
navigation error was immediately corrected after a passenger
turned off a DVD player and that the error reoccurred when the
curious crew asked the passenger to switch the player on again."
A 30 degree navigation error is clearly enough to potentially
make a bad-weather landing attempt non-recoverable...
Other than bodies on the ground (maybe your loved ones...),
how much more proof do any of you want?
You'd all better hope you never try to illegally use a cell phone
on an airplane within my view...
David
Sr. Accident Analyst
First, I do not own a cell phone, so I have no vested interest in proving you or them wrong. My interest is in getting to the truth. I want to know what the facts of the situation are. If I fly, I want to get to my destination safely just like everyone else.
Second, even though I do not work for the airline or cell phone industries, I have a degree in computer engineering, so I am not an idiot either. I am familiar with circuits and electro-magnetic fields and I understand it can be very difficult to predict everything that might happen in a given situation.
That being said, why is there is not a lot more money and effort being put into the study of this situation and into getting current data? Why are we not doing a lot more in-depth studies to find the potential dangers? Why are we not getting this information out there and available? I find that very frustrating.
I always read about someone saying this is dangerous and we should do this or that, but the articles never include the data that was used to come to that conclusion. I want to know, to have the facts as opposed to opinions, so I can be informed and understand. That IS the best way to make decisions, by being well informed. If we don?t have more facts, we desperately need to get them.
I noticed one of the writers of the article you referred to, was the same gentleman referred to in the first article, Mr. Bill Strauss.
In the article it stated that their data was two years old but it was the best available in this area. It also said that theirs was the first documented study of in-flight RF emissions by portable electronic devices, and maybe the first done outside the airline industry. I am amazed that this is not under more study. Why are the people in charge of government spending and the people in charge of airline safety not crawling all over this, doing everything they can to research this issue? And why are we not doing a better job of making available the data we do have? It seems like a casual attitude for something that could be such an important issue.
In their investigation, these individuals set up a spectrum analyzer which recorded that someone made a call, which was also witnessed by the participants. The article says it showed evidence of the call, but that was easily known just by visual observation. The article did not say that it detected the call outside the range of frequencies specified for that call OR that the call signal had moved into the band used by the aircraft. The graphic at the end of the article did not show a signal out of band, just that there was a signal. We don?t need to prove that people use cell phones on airplanes, we know they do. What we need to prove is IF they are dangerous and if so what can we do to fix the situation or reduce the risk.
The article mentioned that the device that had been used to secretly monitor the plane ?had been carefully tested for safe in-flight operation and was allowed on board by the airline and the two relevant U.S. safety agencies, the FAA and the Transportation Security Administration.? If we can certify this equipment (including a laptop) as safe, why can we not require the cell phone companies, device manufacturers and airlines to do the same thing, test their equipment and make it safe for simultaneous use. That is assumes we know what about it is dangerous, if we don?t then we should work hard and fast to find out, and stop guessing.
The second page of the article had some good information for those who wish for a very basic understanding of some elements of the issue but it did little to further the issue of whether or not it is a safety risk.
In one case it did just the opposite, in identifying the signal as a cell phone call, it stated, ?we couldn't conclusively identify the technologies underlying the signals we detected. However, the FCC permits only cellular telephones to operate in these frequency bands and restricts emissions from unintentional radiators. The recorded power levels are also evidence that the signals are due to cell phone use: an unintentional PED radiator operating at the maximum allowable emission level would show up as being at least 70 decibels below that of an onboard cellular signal. That makes it sound pretty well regulated. If they can be sure about these things, then where is the problem, it was a cell phone call in a cell phone band. It is important information but it does not make the point that it is a danger. Maybe there just needs to be a shift in the stress of the article. (just having a car on the road does not make it a danger to the pedestrian)
The article again referred to their research showing clearly ?that, in violation of FCC and FAA rules, calls are regularly made from commercial aircraft.? and again I say that is a given. We need to prove whether it is dangerous and, if so, what can we do about? We also need to ask why all the necessary study hasn?t been done sooner.
The article mentions lack of cooperation between the FCC and FAA. If the government can pull multiple agencies under one umbrella, why can we not require these two agencies to work together for the common safety? Also why can we not require the airlines to install more shielding or redundancy on their aircraft? Is it because of the lack of specific crash evidence of the danger? I see a lot of issues but where is the work being done to correct those issues?
In the final page of the article, several steps are listed that would go a long way to improving our understanding of the situation, making things safer and increasing public knowledge of the situation. I agree with the points made. There is much we need to do. Maybe we even need to go farther, as has been done in other areas, maybe we need pull the responsible agencies under a technical umbrella or set up an agency directly responsible for making sure they communicate and get the job done.
Now come to the issue why cell phones are banned on the planes, because air-lines don't want to take the responsiblity or deal with RF emission issues inside the cockpit, it's a fear issue or annoyance issue. Dagner for airplane landing approach? If cell phone signals are problematic, no one will have a safe landing around any major airports because I can guarantee that around any US major airports there are a signicant amount of cell phone towers, doppler radars and other air traffic communication towers that emits WAY more RF signal power than a few little cell phones. Of course, any RF design would work better if the background environement is as noise free as possible, hence the air port and air lines don't allow people to use cell phone on the plane, for no other reason than not having to deal with the issue and just because they can make you, average joe, to comply. Is there any real technical merit points to direct frequency conflict between cell phone and air traffic control channels? If the answer is yes, then entire staff of the FCC should be fired for doing such a lousy job as allowing a public utility frequency such as a cell phone channel to interfere with vital traffic control channels. This has never happened yet. Could it be possible? Yes. It is likely, not more likely to have air traffic control and GPS signal interfered by the radar installations onsite at the air ports, and no one is banning the use of radar around air ports, yet...
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