JOSS21
Topic Author
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Cell Phone Usage In Flight

Sun Mar 14, 2004 5:55 pm

Does anyone believe that airlines and or FAA will in the future allow the usage of cell phones while the plane is in motion? Do they really interfere with the avionics?
 
IL76
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 6:08 pm

GSM phones don't work in airplanes. The antennas on the ground pick up and send signals horizontally, not upwards. Perhaps, if you're lucky, you might still get some reception when flying low shortly after takeoff or when landing, but otherwise, it wouldn't make sense even switching on your phone. Your phone will start transmitting signals to do a location update (with the nearest antenna) and that might cause interference with the avionics. It's the "tuh-tuh-tuh"-sound you hear for example on your car-radio when the phone rings in your car.
Actually making a call at cruising altitude isn't possible.


[Edited 2004-03-14 10:11:24]
 
JAL777
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 6:10 pm

Not to mention that at the speed the aircraft is traveling you'll be leaving and entering an antenna's reception every few minutes making your cellphone totally useless.
 
COAB767
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 6:13 pm

I heard this story on the news last year I believe, a passenger on a BA flight from SEA going to LHR decided to use his cell phone on take-off, so the pilot had to make an emergency landing just cuz of that.
Continental Micronesia: "Fly With The Warmth Of Paradise"
 
canoecarrier
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 6:20 pm

I disagree with the comment that they don't work at all, they do. Remember 9/11? How many cellular phone calls do we have on record made from the planes while in flight. Not to mention some commercial airlines have a cell phone assigned to each aircraft to be kept in the cockpit.

That being said, I really would rather they continue to be outlawed. Who wants to hear 100 people chatting away on their phones during a 6 hour flight? It truly is one of the last non-cell zones we have left, let's keep it that way.
The beatings will continue until morale improves
 
IL76
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 6:28 pm

I was anticipating that comment.
I was talking about GSM (I'm a Nokia GSM NSS-engineer). Satellite phones work everywhere all over the world, GSM (which most people have) don't. Planes carry satellite phones.
But on 9/11, the planes were not really at cruising altitude anymore, were they? These people managing to make a call were lucky (Sorry for the expression, of course they weren't lucky  Sad)...

 
Mir
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 6:30 pm

I believe that it's not an FAA rule, it's and FCC rule. When you fly in a plane, your higher location above the horizon means that you are in range of more than one antenna at once, which clogs up the system. Thus, the FCC bans cellphones in planes.

That's what my flight school told me.

Mir
7 billion, one nation, imagination...it's a beautiful day
 
canoecarrier
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 6:35 pm

Cell phones may be banned, and GSM phones may work, but the phones we have aren't GSM phones. I still think it's a really bad idea to let the traveling public use their cell phones inflight.
The beatings will continue until morale improves
 
IL76
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 6:38 pm

You are surrounded by antenna's all day. At any point in time (depending on the location) your phone is in contant contact with more than 1 antenne, choosing only the strongest one to make a connection. In a big city, your phone can choose 5+ antennas to connect to.
And, for example, as you drive on a highway and making a call, your phone will request a handover to another antenna when the signal of one antenna weakens, and another gets stronger. The system will not clog up. It's designed with overlapping antennas.
 
IL76
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 6:44 pm

...Anyway, drifting off topic with my GSM comments...

I agree, people shouldn't (try to) use their phones on planes. Even if it is possible, I agree with Canoecarrier, sitting around with hundreds of people chatting on a phone for hours is not fun. It already annoys me on a bus- or trainride, which doesn't take more than 30 mins. Imagine a 6 hour flight with beeping ringtones and such!!
 
planesarecool
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 6:48 pm

I can see how a cell/mobile phone might interfere with the avionics (at home if i have my mobile phone next to the computer, whenever i get a text message or a phone call, or send a text message or a phone call, my computer makes weird noises, and on my friend's computer it freezes the computer temporarily). But does it matter if you actually have your phone on in flight if you don't make or receive any calls or text messages. Because surely then it's just like an electrical object and they're usually allowed aren't they?

-Stephen
 
canoecarrier
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 6:59 pm

You can have it with you, you're just not supposed to have it on. This is the same with MP3 players, laptops, etc. up until an altitude of 10,000ft, except cell phone useage is prohibited inflight.
The beatings will continue until morale improves
 
andz
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 6:59 pm

If your cell is on it is constantly searching for a signal so it is transmitting and receiving anyway.
After Monday and Tuesday even the calendar says WTF...
 
alangirvan
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 7:19 pm

just wondering about using the new Microsoft SPOT devices in flight. These are watches that use radio signals to receive info. Would these be banned?
 
Qantasclub
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 7:29 pm

Yes, but is there any ACTUAL EVIDENCE that they cause interference with the plane's operating systems or is it all just bandwagon stuff-just like all this crap about DVTs and the global airline hysteria over prevention when studies have actually shown that there is no actual statistical risk of a DVT when flying UNLESS you have a pre-existing thrombotic tendancy in whihc case you are likely to develop a clot sometime in your life anyway, flying or not.

I leave my mobile phone on but never answer it throughout the flight.
Long Haul is the only way to go
 
lauda777
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 7:35 pm

If you have a satellite phone the same type as the ones connected in your seat and in the cockpit you should be able to use it as they obviously don't cause interference, after all why should you have to pay the $10 or $12 per minute most airlines charge for a phone call, I realise not many people have satellite phones because of their cost and size but the use of all other GSM and CDMA cellphones should remain forbiden.
We remind passengers all flights are non smoking, if you are caught smoking you will be asked to sit outside on the wing
 
andz
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 7:43 pm

I leave my mobile phone on but never answer it throughout the flight

why not just comply with the rules and switch it off then.
After Monday and Tuesday even the calendar says WTF...
 
Guest

RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 8:27 pm

Cell phones in general should be banned. They are the most annoying things on the planet. Infact now at work I will refuse to help anyone until they get off their phone. Its simple politness.


I dont forsee cells ever being allowed while inflight.
 
jumbopilot
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 11:01 pm

Amwest25:
Cell phones in general should be banned. They are the most annoying things on the planet. Infact now at work I will refuse to help anyone until they get off their phone. Its simple politness.

I sympathize with your feelings. But, on the other hand, for myself the mobile phone (in German called "handy"  Big grin) is a working tool as my notebook, too. I am often on the way and it is the easiest way to remain in contact with my office. But in opposition to some other men I try to use it without disturbing other people (Not always with success, I know).

I cannot understand why some men must use their mobile phone while boarding until starting of engines. It is terrible and nerving to meet with such bad organized guys. In my eyes it is not necessary to allow using of that devices if they are not functioning airborne.
Carpe Diem
 
air2gxs
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 11:18 pm

Lauda777,
Though I'm not familiar with the installation of the sat. phones on aircraft, I do know that all antenna cables are shielded to prevent interference until the signal gets to the antenna. Thus, I imagine the sat. phones are also connected to their antennas via shielded cable, reducing and/or eliminating the chance of interference with other aircraft systems.

Your sat. phone would not have this shielding, thus can/may/will cause interference.

Of course, I could be wrong since I have no experience with sat. phone installations on pax aircraft, I'm just a freight dog.
 
flyingdoctorwu
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 11:28 pm

I have one of the candy bar style GSM phones and one time it accidentally turned on in my pocket in flight- I just happened to check the phone while we were flying over Washington DC- no signal....

I am not sure what sort of interference the cellular signal causes with airline equpment but there are anecdotal case reports of cell phones interferring with medical equipment- specifically cardiac monitoring devices and ventilators. I did a literature search on this and it's rather inconclusive of A)whether or not cell phones interfere and B) whether or not such interference is clinically significant.... Nontheless, if I was flying I would not want anyone to have their phones on, if there is a slight change that some interference causes trouble- you only need one incidence to make a disaster.

Christopher Wu
 
keno
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 11:44 pm

Cell phones should never be used during take offs and landings because they might interfere with the ATC communications. Apart from these critical moments, I don't think there's much harm of using them (if the phone works, that is).
 
Horus
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RE: Cell Phone Usage In Flight

Sun Mar 14, 2004 11:50 pm


Once when I was landing on an Easyjet B737-700 in Luton, and my phone rang and I answered it like a minute before touchdown but nothing happened.

p.s. I forgot to switch it off
EGYPT: A 7,000 Year Old Civilisation
 
air2gxs
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RE: Cell Phone Usage In Flight

Mon Mar 15, 2004 12:34 am

In a perfect aircraft nothing will happen or should happen. But as an aircraft ages problems occur. The thing that concerns cell phone, or any other radio emitting device, is the shielding breaking down on critical wiring allowing stray signals into the wire.

Example: (in simple and general terms)
In a modern autopilot system the computer tells the control surface actuator to move a certain amount to in order to control the aircraft properly. The actuator sends a signal back to the computer (feedback) that tells it that it has moved. These wires are shielded in order to prevent erroneous signals from interfering with this communication. If this shield has broken down (through age, damage, incorrect installation, etc) it is possible that an outside signal can cause an undesired effect. This communication is continuous and happens through-out the entire aircraft.
Therefore, it is critical that these devices that emit signals should not be used during the critical phases of flight.
Cell phone use is troublesome because of the relatively high emissions (compared to a CD player) it produces.

 
Dan6681
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RE: Cell Phone Usage In Flight

Mon Mar 15, 2004 12:54 am

First off I have to say the use of the word cell phone or calling ones mobile phone a cell makes no sense whatsoever and it annoys me every time I hear it.  Smile

IL76;

Working for Nokia you must know our situation in the U.S. regarding mobile phone networks. Our GSM standard being 1900 while the rest of the world with the exception of Mexico, Canada, and Puerto Rico is on 900/1800. Is one more harmful to surrounding equipment then the other? Also I have had a CDMA phone that worked in flight. Are CDMA,TDMA,Amps phones more or less disruptive to surrounding equipment i.e. avionics then GSM.

EWR-SIN 18.5hrs bring it on!
 
kanebear
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RE: Cell Phone Usage In Flight

Mon Mar 15, 2004 1:01 am

I can't remember now where I read it but I recall seeing that a wireless firm was looking into providing an airborne mobile phone 'gateway' that would allow people to place and receive calls with their cellphones while in flight. It would interface with the terrestrial air-phone network and satellite phone services and would provide switching/call processing functionality on board. Since the very close proximity of the antenna would permit operating the mobile devices at a very very low power output level this would minimize any chances of interference. Personally I dread the thought of having mobile access on board... imagine, 3 AM and you're dead asleep in the middle of a transpacific flight and some tosser starts yelling/laughing his head off into his mobile. I would be arrested for murder. Now what I WOULD like to see is on-board WiFi internet access. Due to the spread-spectrum low power nature of wifi that should pose no risk of interference at all and would be a LOT less expensive than cabling up the airplane.
 
Ralgha
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RE: Cell Phone Usage In Flight

Mon Mar 15, 2004 2:14 am

47 CFR

§ 22.925 Prohibition on airborne operation of cellular telephones.

Cellular telephones installed in or carried aboard airplanes,
balloons or any other type of aircraft must not be operated while such
aircraft are airborne (not touching the ground). When any aircraft
leaves the ground, all cellular telephones on board that aircraft must
be turned off. The following notice must be posted on or near each
cellular telephone installed in any aircraft:
``The use of cellular telephones while this aircraft is airborne is
prohibited by FCC rules, and the violation of this rule could result in
suspension of service and/or a fine. The use of cellular telephones
while this aircraft is on the ground is subject to FAA regulations.''
09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
 
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Starlionblue
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RE: Cell Phone Usage In Flight

Mon Mar 15, 2004 2:43 am

Quite apart from the technical reasons which are course are most important, it would be quite rude to talk on your cell in flight.

The signal can be switched to pager, but it's still a crowded place. This also goes for restaurants, trains and other places. I use my cell extensively, both for voice and datacomm. But I try to speak quietly if I am in a public place, and move to a corner where I won't disturb everyone. It grates on my nerves when I have to listen to loudly declaimed shopping lists/customer meeting action points/gossip along with everyone else in the room/compartment.

A typical example occured on the Eurostar from Paris this Friday. This guy's phone rang very loudly. First point, do us all a favor and set it to pager while on board. It's only two presses. He then proceeded to let it ring five times while he checked who it was. Second point, pick up so we don't have to hear "The Nokia Tune" at earsplitting volumes over and over. He then picked up and spoke loudly for ten minutes. Third point, either learn to lower your voice (believe it or not, there is a microphone in there so you don't have to shout) or walk to the space by the carriage doors where we won't have to listen to you.

End of rant...
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
ANA777Master
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RE: Cell Phone Usage In Flight

Mon Mar 15, 2004 2:57 am

Anyone who uses a cell phone on a flight, for a non-emergency, deserves a boot in the face, in my opinion.
 
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Starlionblue
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RE: Cell Phone Usage In Flight

Mon Mar 15, 2004 3:27 am

Or at least public service in the form of washing AF 744s  Big grin
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
CWUPilot
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RE: Cell Phone Usage In Flight

Mon Mar 15, 2004 3:41 am

Mir is correct. The FCC says it will take away your service/impose a fine if you use a cell phone in flight, weather it's at 1,000' or 39,000' agl. This is because your one signal will tie up many antennas.
Screw it though, I use it all the time myself if in VFR and I need to let someone at my destination know to come meet me at the airport. This is of course in GA aircraft when I'm in command.

-CWUPilot
"The worst day of flying still beats the best day of real work."
 
XFSUgimpLB41X
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RE: Cell Phone Usage In Flight

Mon Mar 15, 2004 3:55 am

Canoecarrier- the phones worked on 9-11 because the airplanes were flying on the deck... I always used to keep mine on when i was instructing..works like a charm below about 8-10000 feet.
Chicks dig winglets.
 
NWA ARJ
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RE: Cell Phone Usage In Flight

Wed Mar 17, 2004 2:52 am

Actually I do not believe that it is a FAA rule that says no cell phones. My ground instructor at UND explained to us that it is a FCC rule because they would not know how to bill people when they are up in the air. Also of note cell phones would not interfere with ATC communications.
Nightmare 68, Fargo Tower, Runway 36, Fly Runway Heading, Mantain 10,000, Cleared For Takeoff, Change To Departure
 
avioniker
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RE: Cell Phone Usage In Flight

Wed Mar 17, 2004 6:16 am

Cell phones emit an RF signal at a tuned frequency.

Interference with that signal causes harmonics which are multiples and fractions of the tuned frequency.

The end of the phone antenna, unless it is a perfect sphere, provides interference.

Any signal will interfere with any other signal to an extent dependant on the relative strength of the signals and the quality of the shielding of the carriage medium. (i.e. coax, twisted wire sets, insulated wire, air, etc.) If any defect exists in the shield of either receiver's antenna lead the phone has the capacity to cause navigation errors, uncommanded flight control inputs, fuel quantity fluctuations, communication interruptions, etc. All of these malfunctions and forms of interference have been demonstrated and proven.

Cell phone emissions interfere with all radio spectra in flight. That is simply a fact.

As for the comment about it not being in the FAR's

§ 121.306 Portable electronic devices.
(a) Except as provided in paragraph (b) of this section, no person may operate, nor may any operator or pilot in command of an aircraft allow the operation of, any portable electronic device on any U.S.-registered civil aircraft operating under this part.

(b) Paragraph (a) of this section does not apply to—

(1) Portable voice recorders;

(2) Hearing aids;

(3) Heart pacemakers;

(4) Electric shavers; or

(5) Any other portable electronic device that the part 119 certificate holder has determined will not cause interference with the navigation or communication system of the aircraft on which it is to be used.

(c) The determination required by paragraph (b)(5) of this section shall be made by that part 119 certificate holder operating the particular device to be used.

[Doc. No. FAA–1998–4954, 64 FR 1080, Jan. 7, 1999]


Turn off the damn phone and quit trying to impress yourself and those around you with your self importance.
One may educate the ignorance from the unknowing but stupid is forever. Boswell; ca: 1533
 
sovietjet
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RE: Cell Phone Usage In Flight

Wed Mar 17, 2004 7:16 am

On 9-11 the planes were flying at a low altitude therefore it was possible.
 
dc10hound
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RE: Cell Phone Usage In Flight

Wed Mar 17, 2004 10:17 am

And if you want comprehensive technical data from another source:

http://www.caa.co.uk/docs/33/CAPAP2003_03.PDF

"The tests covered the cellphone transmission frequencies of 412 (Tetra),940 (GSM)and
1719MHz,including simultaneous exposure to 940 and 1719MHz.The applied interference
field strengths were up to 50 volts/metre for a single frequency,and 35 volts/metre for dual
frequencies.
The following anomalies were seen at interference levels above 30 volts/metre,a level that
can be produced by a cellphone operating at maximum power and located 30cms from the
victim equipment or its wiring harness.
•Compass froze or overshot actual magnetic bearing.
•Instability of indicators.
•Digital VOR navigation bearing display errors up to 5 degrees.
•VOR navigation To/From indicator reversal.
•VOR and ILS course deviation indicator errors with and without a failure flag.
•Reduced sensitivity of the ILS Localiser receiver.
•Background noise on audio outputs.
Most anomalies were observed at 1719MHz.
The project was managed by UK CAA and assisted with loaned equipment and personnel from
Vodafone PLC,CSE Aviation (Oxford),and BAE SYSTEMS (Woodford).


And

Recommendations

"The results of the tests endorse current policy that restricts the use of cellphones in aircraft.

Recommendations are made that would further reduce interference risks,and to continue thestudies to determine interference effects in aircraft from cellphones and other transmitting devices.

CAA will remind operators about the specific risk from cellphone usage on the flight deck, and recommend that confirmation be obtained from passengers at check-in that cellphones in their luggage have been switched off."


I didn't study it closely. Sounds good enough for me.


"Eagles soar. But weasels never get sucked into jet intakes.."
 
777ualsfo
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RE: Cell Phone Usage In Flight

Wed Mar 17, 2004 1:14 pm

I agree with everyone so far- allowing cell phone use on board would be a flight from hell. It is bad enough to hear everyone yakking away during the boarding procedures.
 
jwenting
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RE: Cell Phone Usage In Flight

Wed Mar 17, 2004 1:56 pm

Another reason why cellphones in the US (at least SOME networks) may work while GSM phones do not is because they're based on different technology.
GSM is only now becoming available in the US, most networks still use older analog technology that was abandones in Europe circa 1997 (heck, I worked for KPN at the time on the traffic processing software when they were phasing out the analog network).

Those old-style phones have a longer range (and correspondingly greater transmission power), I wouldn't be surprised if they work at higher altitudes as well.

But the main reason (apart from aircraft safety, which with modern low-power GSM phones might no longer apply, but do you want to give every FA a course in recognising which phone is what type, maybe giving them a checklist you update every day stating exactly which makes and models are allowed and then having to deal with irrate passengers demanding they may use their phones if their neighbours can use theirs...) is social.
Restaurants and cinemas ban cellphones, and their use in an aircraft would indeed drive passengers crazy. People'd constantly be calling and being called, leading to them all shouting ever louder in an attempt to be heard over all the others shouting into their phones.
I wish I were flying
 
CPDC10-30
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RE: Cell Phone Usage In Flight

Fri Mar 19, 2004 1:32 am

in the US, most networks still use older analog technology that was abandones in Europe circa 1997

Acutally, there are very few analog only phones used anymore, or for the past five years. Many phones in the USA and Canada are CDMA or TDMA with backup analog mode, although GSM is getting a lot more popular. From my course in mobile communications, the main reason that no one wants cell phones used in flight is that multiple cell sites are tied up at the same time for one call.
 
iakobos
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RE: Cell Phone Usage In Flight

Sat Mar 20, 2004 12:18 am

One major reason why cellular phones should be switched off onboard aircrafts is related to security. 10 grams of plastic explosive hidden inside can blow off a head. Calling that particular phone triggers the "bomb", think about what it can do the plane. Israeli services used the system to "liquidate" a major Palestinian figure not so long ago...he received the brand new phone as a gift from a "friend".

Cellphones, be it NMT, GSM, AMPS, TACS, TDMA, CDMA, work generally well inside aircrafts, although at altitude ones needs to be pretty close to a window. Pilots do use their cellphones quite often.

An integral satellite-phone, be it Iridium, Globalstar, Inmarsat or Thuraya, will not work inside a plane, unless it is connected to an external antenna.
(which is the case with sat-equipped planes)

Cellphones (max 2W) and sat-phones (usually 2W but up to 25W) are subject to very strict and intricate tests (US FCC, European ETS, etc..) before being approved. The same principle goes of course for all electronic equipment onboard a plane.
Now, whatever "clean" an electronic device is, if it is designed to radiate energy, it will do so. This means in practice that i.e. a GSM phone will radiate up to 2W on a specific frequency, either during a call or during regular handshaking sessions with the network (which are transparent to the user).
These Watts are radiated by the antenna to produce a magnetic field (expressed in microvolt/meter).
2W of (effectively) radiated energy corresponds to a magnetic filed of 3.5V at a distance of 2 meters, 0.7V at 10 meters, pretty insignificant in any case (EXCEPT when directional antennas are used).
In addition, unwanted energy will also be produced at "harmonic" frequencies, i.e. at multiples of the "fundamental" frequency. These harmonics are created by non-linear devices in the electronic circuits. Eventhough filtering takes place, they are not totally cancelled but their level is several thousand times lower than the fundamental, we are talking microWatt or even nanoWatt here, close to nothing, and very substantially lower than all the fields produced by high power stations (AM, FM and TV broadcast, military stations, satellite ground stations, and the top of it: ultra high power submarine communication stations).

So, how can a tiny cellphone be found guilty of "interfering" with airborne equipment ? if everything was working as it should, it cannot.
Aircraft devices do not work in the same frequency bands of course, so no "interference" possible due to "signal pick up".
Actually there is only one possibility:
* the aircraft's device is not immune or insufficiently immune to a magnetic field when confronted to it. In the case of a cellphone, the distance between the phone and the device must be extremely small, talking cm here !
If the device's performance (and its associate wiring) is perfectly in accordance with the rules, a problem cannot occur.
However, AND THIS IS IT, any unshielded or non-linear component can "pick up" that magnetic field and distribute it further down the line of circuits.
(an example of non-linear component is a "bad solder" point)
Conclusion: in theory nothing should happen, in practice noone will dare to say that everything is perfect in an aircraft.
Add to this the fact that allowing cellphone usage would obviously result in what everybody can imagine...

Not convinced ? think about all the aircraft systems that do radiate energy (VHF, HF, SAT, transponder, radar, TCAS, etc....), quite a bunch more than several cellphones.

Sorry if I was long...hoping it helped address some questions and correct misconceptions.




 
funflyer
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RE: Cell Phone Usage In Flight

Sat Mar 20, 2004 3:02 pm

Um, first I dont care if it interferes with anything, It would just be DAMN annoying, imagine like 100 people on there damn phones!
Who cares about status?
 
XFSUgimpLB41X
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RE: Cell Phone Usage In Flight

Sat Mar 20, 2004 11:11 pm

"Cellphones, be it NMT, GSM, AMPS, TACS, TDMA, CDMA, work generally well inside aircrafts, although at altitude ones needs to be pretty close to a window. Pilots do use their cellphones quite often."




That is incorrect. Your cellphone does not work at altitude..cell phone antennas don't point up...esp not 7 miles up. Sure I use my cell phone quite often... on the ground, with the door open. Just when it is legal to do so.
Chicks dig winglets.
 
Rick767
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RE: Cell Phone Usage In Flight

Sat Mar 20, 2004 11:34 pm

The CAA report DC10hound mentioned was really a bit of an impractical analysis of the risks and effects of cellular phones used by passengers, with aircraft instrumentation.

a cellphone operating at maximum power and located 30cms from the
victim equipment or its wiring harness


What passenger is within 30cm of any "critical device" wiring on the aircraft. Answer: none. And yes, I know wiring runs all over the aircraft, but not for the critical devices the CAA tested, relative to the passenger within 30cm.

I would be willing to bet every commercial flight I have operated in the last 6 months is very likely to have had at least one active mobile phone on board for the duration, it is almost guaranteed.

In the past, it has been my own or the Captain's phone, which we have used on the ground at the destination and then neglected to switch off before engine start.

I have never experienced any anolomy with flight instruments which I consider were caused by cellular equipment. At the end of the day the risk is tiny, and you will never prevent people from having phones switched on in the cabin (since it is mostly accidental). As a passenger, I have realised my phone was switched on during a flight... it happens so don't believe that half the commercial planes in the sky right now have no cellphones switched on!

The ban on their use in flight should of course still remain, since the combined effect of several such devices remains unknown, but in general the risk is hugely over-hyped.
I used to love the smell of Jet-A in the morning...
 
airplay
Posts: 3369
Joined: Sat Oct 25, 2003 1:58 am

RE: Cell Phone Usage In Flight

Sat Mar 20, 2004 11:58 pm

I leave my mobile phone on but never answer it throughout the flight.

First and foremost, it is quite irresponsible to experiment with other passenger's lives because you don't believe or fail to understand why specific rules are in place.

I have never experienced any anolomy with flight instruments which I consider were caused by cellular equipment.

Again, I find it quite irresponsible to use a loaded airplane as a science experiment! I have personally witnessed numerous interactions with different devices, cell phones included that had the potential for introducing a hazard and although it is a rare occurance, it is possible.

The hazard probability analysis that is typically performed for aircraft systems are designed to ensure that catastrophic failures are extremely improbable and major failures are improbable. Cell phone emmissions can cause a hazard, and you need to understand that when they are stowed in various areas, in the overhead or even in a flight bag or in a jacket or bag on the floor under the seat in front of you, they can be transmitting at maximum power seraching for a station.

The analysis proves there is an unacceptable level of probability of operating cell phones in aircraft so why do it?

From the FCC side of things, next time you try to call somewhere and the cell phone call fails because of system over-capacity, think about how many cellphones flying around at low level are taxing the cell towers in range....



 
Rick767
Posts: 2613
Joined: Sun Jan 30, 2000 8:11 pm

RE: Cell Phone Usage In Flight

Sun Mar 21, 2004 2:08 am

"I find it quite irresponsible to use a loaded airplane as a science experiment!"

That's the point though - the "science experiment" as you put it is occuring all day, every day with a high proportion of aircraft departing with an active cellphone in the passenger cabin from the sheer unawareness of passengers and crew members alike that they have not switched the equipment off.

Without intense, costly screening of passengers for this equipment, how can this ever be stopped? And how many bags make it into the hold with a live cellphone inside?

I am not condoning the use of cellular equipment on aircraft, but let's be realistic here - if interference is potentially possible either with the cellphone networks or aircraft equipment, that is for the manufacturers of that equipment to resolve - because the 'problem' itself will never go away.
I used to love the smell of Jet-A in the morning...
 
artsyman
Posts: 4516
Joined: Wed Feb 28, 2001 12:35 pm

RE: Cell Phone Usage In Flight

Sun Mar 21, 2004 5:40 am

I also find it odd the amount of cell phone calls from 9.11. I, and every single one of my friends in inflight at Continental have yet to ever get a signal on any one of the flights we have been on and tried. Personally, I have tried about 10-15 times, and not once did I get a signal, others have tried also, so it seems odd that people managed to get a signal on 9.11.
 
iakobos
Posts: 3255
Joined: Wed Aug 06, 2003 6:22 pm

RE: Cell Phone Usage In Flight

Mon Mar 22, 2004 8:54 pm

XFSUgimpLB41X
Cellular base stations are in most cases using directional antennas. These are both directional in azimuth and elevation, according to what area it is intended to cover.
The antenna(s) "beam" in elevation is only a few degrees wide, however the antenna has a very significant gain.
When the cellphone is used in an aircraft at high cruise level, there is no doubt it will not connect to a base cell immediately below it, but it can perfectly pick up a base cell a few dozen miles away, even quite far away.
 
Moolies
Posts: 476
Joined: Fri Nov 07, 2003 2:59 am

RE: Cell Phone Usage In Flight

Mon Mar 22, 2004 11:23 pm

On a flight on a 738, a few friends and I were going to a rowing regatta for the weekend. On the approach a space kadet friend of ours had left his phone on and it rang. It was Deacon, the eyes of the fellow PAX became the sizes of saucers. This one guy says Deacon im in a plane, oh well then you can chat he responds. I have never seen so many frightenend people in my life.
 
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clickhappy
Posts: 9042
Joined: Thu Sep 13, 2001 12:10 pm

RE: Cell Phone Usage In Flight

Tue Mar 23, 2004 5:48 am

bottom line is this, given the security around planes and flying these days, would they let us take our mobils onboard if they posed a real threat?
 
mhsieh
Posts: 327
Joined: Thu Jul 20, 2000 2:28 pm

RE: Cell Phone Usage In Flight

Tue Mar 23, 2004 1:06 pm

On 9/11, the calls were made from in-flight phones (those found on the seatbacks of the middle seat) and not personal cellular phones.
I never heard of anyone being able to talk on cellular phones while in-flight.

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