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Navajo8686
10th Dec 2004, 08:27
I know that there have been a couple of previous threads on this topic but cannot find a reference to this particular incident.

Apparently at the end of 1998/start of 1999 a BA 767 los radio contact with LHR ATC (so my old copy Aviation News tells me). The problem was solved by BA ringing the crews' mobile and relaying to/from ATC.

Why didn't the mobile seriously affect the plane? Why would the crew have it on?

If the answers obvious then apologies in advance!

Thanks

Navajo8686

eal401
10th Dec 2004, 08:46
No idea, but I am well aware that mobile phones do not affect aircraft. At least in that none have crashed when it happens on a regular basis.

As for the concept of creating the means to permit phone use on a plane, I would respond in the following manner;

NOOOOOOOO!!!!!!

Thank you.

foxile
10th Dec 2004, 08:54
I couple of years ago I took a flight from Moscow to St Petersburg and for nearly the whole flight a guy across the aisle was on his phone.

The crew passed him on a number of times and said nothing. Mind you he was over two metres with a short hair cut and black leather jacket so I was not going to argue either!

Needless to say we arrived at our destination in one piece.

Stockpicker
10th Dec 2004, 09:00
I was assuming that it was just to do with the likelihood of interference when the flight deck are talking to ATC - the "may interfere with aircraft systems" bit is just a catch-all phrase, isn't it?

flapsforty
10th Dec 2004, 09:11
Know not of your specific case Navajo, but as you say, the subject has been debated ad nauseam both on R&N and on Tech Log.
Here in Norway, Scandinavia have had several instances of Aircraft systems going haywire and then going back to normal when ALL pax had switched off their mobiles. Both times the empirical evidence suggested the cause was the phones, but no one was able to reproduce the problem later in a scientifically significant manner.

Personally I have had it once; pilots asking me to make a 'switch yer bleeding mobs off NOW' announcement and no more problems in the cockpit after that. So scientific or not, with the above in mind, I'll try and make sure they are damned well switched off!
Why take the risk when you don't have to?

Obviously, Navajo's case they rather had to! ;)

panda-k-bear
10th Dec 2004, 09:23
Flaps is right - proving it is damn hard. But follow the logic - the aircraft's wiring is partly shielded, but from a transmitting source so close to the aircraft wiring - and perhaps directly under the comms antenna? Ever had someone ring you on your mobile whilst you were talking on a landline? Notice the interference? Imagine what that could do to nav, comms or control equipment onboard.

Airbus is currently trying out a GSM system on an A330, apparently, to see if mobiles could potentially be used aboard. Technically it seems feasible (according to the press release, at least) but would an airline ever accept it? I sure as hell wouldn't fly with an airline that permitted it - not from a safety standpoint but imagine being on an overnight flight and people's mobiles going off every 10 minutes? It's the nature of the beast - international travellers are being contacted by other international travllers in different time zones...

Navajo8686
10th Dec 2004, 09:37
Panda-k-bear

I agree!

It's bad enough on the bus with some Vicky Pollard type having a domestic with her 'thug of a boyfriend' by mobile - gawd knows how much worse it would sound at 35k feet!


Navajo8686

Grainger
10th Dec 2004, 09:50
You've all heard the "badup-bleep-bleep-bleep" noise through your TV, radio, or computer speakers when your mobile's interrogating the network.

Now imagine having that going off in your headset when you're in the middle of receiving a complicated clearance. :mad:

BahrainLad
10th Dec 2004, 10:02
A significant amount of opposition to the use of mobiles on aircraft actually comes from the telecoms networks operators.

Consider the following:

a) When you're at 35,000ft you are in range of a number of base stations ('cells') rather than just one....this confuses the hell out of the network, not to mention the billing system.
b) Moving from cell to cell at 550mph+ means that handovers need to take place almost continuously, and again, this confuses the network. They have enough trouble with high speed trains.

As soon as the airlines install transmission equipment onboard aircraft (so that you have a 'cell' onboard) then the operators will go for it........and they'll be able to charge premium rates.

Big Hilly
10th Dec 2004, 11:17
No idea, but I am well aware that mobile phones do not affect aircraft. I'm sorry eal but, WHAT UTTER RUBBISH!

I might suggest that you read this paper by the CAA (http://www.caa.co.uk/docs/33/CAPAP2003_03.PDF) and draw your attention in particular to the following:
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.
BH

eal401
10th Dec 2004, 11:28
I'm sorry eal but, WHAT UTTER RUBBISH!
Of course it is.

I'll tell that to the PPruNer who told me about it happening on a regular basis on 757 and 737NG aircraft with a subsequent total lack of the aircraft crashing, loop the looping etc. etc.

eastern wiseguy
10th Dec 2004, 11:31
Of slightly more concern...on the ground at Luton the other evening a colleague was switching his phone off......as he did so he said "bye bye" or something equally innocuous into the mouth piece.He was challenged then by an "off duty captain" of the airline who presented his pass and began to berate him regarding the dangers of his now INACTIVE phone(I should say the doors were open and there was no evidence of refuelling taking place).

Fair enough you may say...HOWEVER the same off duty captain then began to TALK EXTREMEMLY LOUDLY THROUGHOUT THE ENTIRE SAFETY BRIEF! I know which I prefer.......

ps ...how come US aircraft let you use your phone on the ground?

419
10th Dec 2004, 11:33
On the 29th April 2004, a Super Puma L2 (helicopter) was returning from offshore. As it was on the approach to it’s destination airport, a passenger used his mobile ‘phone. This resulted in the loss of all flight and navigation information on both pilot’s Integrated Flight Display System screens lasting one second during this critical phase of flight.

The UK Civil Aviation Authority carried out tests on two parked aircraft to find out the potential dangers of mobile ‘phone use. It found evidence that they produced interference levels which could disrupt aircraft systems. Faults attributed to mobile ‘phones include false cockpit warnings, malfunctioning of aircraft systems, interference in pilot’s headsets – all distracting the crew from their primary task.[Quote}


[QUOTE]No idea, but I am well aware that mobile phones do not affect aircraft.
Tell that to the crew on the aircraft above.

419

Big Hilly
10th Dec 2004, 11:44
I'll tell that to the PPruNer who told me about it happening on a regular basis on 757 and 737NG aircraft with a subsequent total lack of the aircraft crashing, loop the looping etc. etc. Hang on a minute. I didn't realise that we were looking at this from a 'Daily Mail' point of view - you know the sort of thing "Mobile Terror in the sky; mobile phone causes all six engines on the Airbus 737 to shut down as it spins out of control. . . ." - I thought we were talking about a scientific and SAFETY point of view. You said above:I am well aware that mobile phones do not affect aircraft. which is blatantly incorrect. I don't know whether you fly (your profile doesn't seem to indicate) but if you do, you may well have left your mobile on in your pocket and heard the 'da-ditty-da-dittyda-ditty' noises from your phone as it tries to log onto a cell? Well, here's some news for you - THAT'S YOUR MOBILE AFFECTING THE AIRCRAFT - albeit just the sound you hear in your headset. The CAA have shown that mobiles do have an effect on several a/c systems such as the ILS receiver and that these might, just might pose a possible threat to the safety of the flight.

At the end of the day, the rules exist for a very good reason, and if it's that much of a hardship to turn off your mobile for a few hours then go by train or boat!

Regards

BH

Jerricho
10th Dec 2004, 12:08
No idea, but I am well aware that mobile phones do not affect aircraft

EAL, once again you're talking crap. As Grainer has mentioned, to start with there is the issue of it affecting comms equipment. Myself, I have been sitting at a radar console and had the same interference thing go through my head-set just prior to somebody's phone going off behind me.

Come back when you know what you're talking about.

panda-k-bear
10th Dec 2004, 12:49
Now you see, it does and it doesn't. Yes it CAN interfere. It's a question of adequately shielding the wiring and systems from the transmissions of the phone. Today, yes it does affect aircraft systems. In the future it might not, hence the GSM experiments to check out what really happens and how much shielding is really needed.

AUTOGLIDE
10th Dec 2004, 17:13
The problem isn't interference with radio comms, a VHF transmitter kicks out about 125 watts, and is AM VHF, mobiles are digital and not very powerful, but unfortunately not electrically bonded to the airframe and inside it.
The problem is when the mobile is 7 miles up and on max power trying to contact a station, the result is electromagnetic induction into the aircraft wiring interfering with small signal systems.
I thought there was a trial using an internal mobile 'earth' station, whereby mobiles could be used but due proximity to the repeater station would be emitting very low power signal which wouldn't interfere with small signal systems.
Thing is, imagine your boss phoniong all the time all the way across the Atlantic, or those loud pointless converations all around you...total air rage!

slim_slag
10th Dec 2004, 18:22
Big Hilly, that report is not applicable to what goes on in the real world. NDB approaches are real world and far more dodgy.

CarltonBrowne the FO
10th Dec 2004, 19:00
eal401, no one is saying that mobile phones ALWAYS have an effect- just that they do SOMETIMES.
I've moderated my tone for this post because it's obvious you don't know what you're talking about.

niknak
10th Dec 2004, 23:58
Last night a regional carrier was on final to land when the crew got a fire warning light in one of the holds, this resulted in a full emergency being declared, all operations at the airport concerned being suspended for 15 minutes and the attendance of the local police, fire and ambulance services, in line with standard procedures, and the aircraft being evacuated.

The crew suspected that it was as a result of a mobile phone being switched on, because they heard the tell tale noises in their headsets, but the warning light stayed on and they had to assume that there was a fire on board.
On other similar aircraft in similar circumstances, the crew had had door warning and other such indications.

The captain spoke politely to passengers who were seated in the relavant area, and a chap had the honesty to admit that he'd switched on his phone at precisely the time the incident occured.
Neither the airline or the airport authority intend to take any further action against the passenger concerned.

However, it proves that there's a long way to go before the full use of mobile phones on aircraft can be permitted.

Milan N
11th Dec 2004, 08:27
25 february traffic managers of aeroport "Ulyanovsk-East" took to boarding cargo ÀN-124-100 of air companies "Flight" and passenger planes "Volga-Dnepr" and "Perm airways". When liners are prepared to call at to boarding, signal from land was interrupted by the unknown transmitter. Certain men on the frequency talk about love with his girlfriend. Technical aeroport service fixed only their talk and did not get signals from boards. In the interim in earphones of pilots was silence as in the tank. Liners have to whirl good while midair, previously than hear call sign from land.
Policeman did not form a labour to delay a violator. They are renderred student, which dirt-cheap has gained from hands uncertificated radiotelephone of big radius of action. Buying was double cheaper than mobile. Having Installed beside itself building a base of radiotelephone it could use a tube in any spot of city. And herewith nothing not to pay for voiced - a number-that town. However telephone was not certificated, frequency, to which it is renderred adjusted, was already used by Ulyanovsk aeroport.

ShyTorque
11th Dec 2004, 10:01
I can confirm that baggage bay smoke detector/ fire alarm CAN be set off by mobile phones, even if no call is being made. We have experienced this a number of times, in addition to interference on radio/intercom as the phone attempts to log on to different cells in flight. I now make a point of explaining the problem in no uncertain terms to pax during the safety brief, especially as our baggage bay has no fire extinguisher system.

Big Hilly
11th Dec 2004, 10:13
slim, NDB approaches are real world and far more dodgy. True to a point but NDB approaches are APPROVED by the CAA and also NDB technology has been around for a hell of a long time - therefore we know all about it's 'foibles'. Mobile phones, however, are still a relatively new technology; they ARE affecting aircraft and, as yet, we simply don’t know enough about them so, on my aircraft, they stay well and truly switched-off!
that report is not applicable to what goes on in the real world.
Urmm, it is applicable and it IS happening "in the real world"!

BH

419
11th Dec 2004, 10:15
Is it only me, or has anyone else noticed, that following all the postings here showing how mobiles CAN affect aircraft systems, one particular person seems to have gone very quiet.

419

Big Hilly
11th Dec 2004, 10:21
419,

I too had noticed that - the phrase 'tail between legs' sprung to mind.

It’s also interesting to note that the only two people who attempted to support the use of Mobile Phones on planes appear not to be pilots. The first’s occupation is listed as a ‘Management Consultant’ the second’s as ‘Ski Bum’!

Just goes to prove that a little knowledge is a very dangerous thing!

BH

slim_slag
11th Dec 2004, 14:03
Ah big hilly, when did I support the use of mobile phones on a plane? I just poo-poo'd the report as evidence of what can happen on a real-world commercial jet.

What do you say about all those mobile phone towers smack bang on the Runway 27 threshold at East Midlands Airport? Must be around where you lot have to decide whether you continue that Cat IIIB approach. I suspect the base stations throw out a lot more RF energy that hits the airframe than a phone, inverse square law accepted and all that.

Jerricho
11th Dec 2004, 14:08
One notices Mr EAL has gone a little quiet.

Perhaps he's testing the theory. Hope he doesn't get into trouble :E

419
11th Dec 2004, 14:36
Slim shag,
You are correct, in that the masts do indeed transmit far more RF energy than a mobile phone. The main difference being that the aircraft wiring and avionics are protected from the external energy by the aircraft skin, but this is not the case with a phone inside the aircraft, which may only be inches from a wiring loom.

Compare it to an aircraft lightning strike. 500,000 volts can hit the aircraft, and it will be dissipated by the aircraft fuselage. (the aircraft skin acts as a Faraday cage, and no, or very little energy passes through. imagine the outcome if only a fraction of it hit inside the avionic bay.

419

slim_slag
11th Dec 2004, 15:00
419,

Thanks for your explanation of how the fuselage acts as a faraday cage.

Not long ago I was on a flight which was delayed after all pax got on it and it had left the gate. Captain came on and said 'in this one instance you can use your mobile phones to call ahead and tell people you will be late'

Bugger me, I looked at my phone and had five bars! I could make and receive phone calls within the faraday cage. How the heck did that happen???

Big Hilly
11th Dec 2004, 15:16
slim_slag,

I just poo-poo'd the report as evidence of what can happen on a real-world commercial jet. I'm afraid you're looking at this from the wrong angle. The report shows exactly what IS happening 'on a real-world commercial jet', FACT!

BH

slim_slag
11th Dec 2004, 15:31
big hilly

Limitations of test

The equipment selected for these tests represented a very small sample of avionic equipment in general use. Whilst the results provided an indication of the types of problem that can arise, assumptions about their applicability to other equipment should be made with due caution.Choice of Avionic Equipment To obtain maximum yield from the test programme, several items of avionic equipment were selected to create a system representative of equipment currently in use but designed and qualified to the earlier, less-demanding standards (RTCA DO-138 and DO-160). Although airline equipment would be the preferred choice, practical considerations of equipment availability, its size, power requirements, and complexity of the system interface, restricted the choice to general aviation equipment.

Not real world in the commercial arena. Did you look at the picture of the kit on the test rig, that's more ancient that a lot of stuff you will find on your 172s (but not all, ? Whats that huge horn antenna doing there, haven't got one of those on the end of my phone.

What I'm saying is that report is not evidence of a problem in commercial jets.

So what about that Cat IIIB approach?

You should be a ski-bum, it's more fun than flying :)

Big Hilly
11th Dec 2004, 15:59
slim,

OK, I'll put this in simple terms: The report corroborates what pilots have been experiencing in real-life-every-day-non-ms-flight-simulator-hairyplanes. It goes on, it happens, it takes place, it occurs, cell phones do interfere with aircraft systems, be it just the ‘da-ditties’ in the headset or anything else.

Yes, the test was done in a lab but so were most of the tests that allow modern aircraft to evolve from being wooden models – it doesn’t mean that the results of the test are of less worth because they didn’t do them in a 747 halfway across the Atlantic ocean. But hey, if you want to pick up the tax bill for the CAA to do the very same test in an airborne 747 then I’m sure the Inland Revenue would be only to happy to relieve you of some cash!

I’m not even going to start on the CAT III approach, I’m off to train to be a ski-bum, you’re right, it’s gotta be easier than this. . . .

Regards,

BH

419
11th Dec 2004, 16:18
Bugger me, I looked at my phone and had five bars! I could make and receive phone calls within the faraday cage. How the heck did that happen???

Simple. Whilst the fuselage acts as a faraday cage, due to the fact it has windows, it will never be perfect.
So, even if only 50% of the RF is stopped, your mobile will still pick up the signal.
But, all of the mobile phones transmitted energy can pass through the wiring looms.

In answer to one of your earlier points about the power from the base stations. (This assumes a base station with a 60 watt output, and a phone with a 2 watt maximum power. Both of which are about the maximum in use in the UK

By the inverse square law, the maximum intensity in the main beam at a point on the ground 50 m from a 10 m tower carrying an antenna transmitting 60 W into a 120 sector is about 100 mW/m2. This corresponds to oscillating electric and magnetic fields of about 5 V/m , very roughly about 50 to 100 times smaller than those 2.2 cm from the antenna of a mobile phone..

419

Luke SkyToddler
11th Dec 2004, 16:19
My last job was flying an ambulance aircraft for a couple of years back in NZ, that not only had a mobile phone kit on board, it was STC'ed and it was wired into the intercom so you could use it hands free through your headset.

Nothing special about the phone, it was a bog standard flip type motorola of the typical late '90s design. It wasn't shielded or used a special antenna or anything, just sat in its little cradle on the dashboard like a carphone. We used it all the time to coordinate with our ground ambulances whilst airborne. And yes I've done NDB, ILS, GPS and most other kind of approaches while I've been using the thing.

I've flown in several light piston types back in NZ that had a similar system installed.

What's the problem?

419
11th Dec 2004, 16:29
I've flown in several light piston types back in NZ that had a similar system installed What's the problem

No one has said that it will definitely cause a problem, only that it can, and sometimes does. Why take the risk.
One of the biggest problems is that mobile phones are becoming more powerful, and aircraft avionics are becoming more complicated and computerised all the time.

I don't know the type you flew in NZ, but being "light piston types", I would be very surprised if they had digital autopliot, EFIS, etc. If there was ever a problem on your aircraft, I'm sure the pilot could fly manually. This might not be the case with a modern fly by wire aircraft.

419

slim_slag
11th Dec 2004, 18:36
No one has said that it will definitely cause a problem, only that it can, and sometimes does. Why take the risk.

So you have accepted that RF from mobile phone base stations can penetrate the cabin, which is where the wire looms are. If you cannot quantify the risk, why stick mobile phone towers right next to the end of a Cat IIIB approach?

Why take the risk? Perhaps because there isn't one?

CarltonBrowne the FO
12th Dec 2004, 00:00
It may have escaped your notice slim_slag, but the Crossair Saab 340 accident has been attributed to interference from an onboard mobile phone. Something made the autopilot and Flight Director systems lose their attitude the standby gyro system also drifted off. Coincidentally, at the same time a mobile phone can be heard on the CVR...
419 has already given a thorough explanation why ground stations pose no threat to aircraft systems. Let me put it more simply for you: a close weak signal is more dangerous than a distant strong signal.

419
12th Dec 2004, 09:15
So you have accepted that RF from mobile phone base stations can penetrate the cabin, which is where the wire looms are. If you cannot quantify the risk, why stick mobile phone towers right next to the end of a Cat IIIB approach?

The figures I gave, did quantify the risk. Just because the RF energy penetrates the fuselage, does not mean it poses a risk (provided it is low enough, which in the case of mobile masts the energy if very low).
A 200 W HF aircraft transmitter, or a 20 W VHF aircraft transmitter will produce far more of an induced signal in a wiring loom than transmissions from a phone mast mast will ever do. Would you consider banning them as well?


Why take the risk? Perhaps because there isn't one?
In the case of phones inside the cabin, I think the number of cases highlighed on this thread have proved that there is a risk.

419

radeng
12th Dec 2004, 11:15
We had a beautiful new screened room at work, costing some £40k. Although it had about 90dB of attenuation, you could still use a mobile phone inside it.......

Total power from a base station can be as high as 1600watts. However, that's split between sectors and between bands - 900 and 1800MHz.

The effects of a TDM signal, which is pulsed, may well be very different to an amplitude modulated VHF comms signal, or an HF SSB. In fact. almost certainly different, and likely to be much more deadly to a servo. I do wonder, though about that beautiful surveillance radar at LHR, with its enormous effective radiated power (2giga watts from memory - it may be only 1)

ICAO have intimated that it will be many years before commercial airliners all meet an immunity of 20V/m, while keeping that over service life with abrasion of cable screens, corrosion etc may well be difficult.

Having been involved with producing EMC standards and working in radio frequency design for 40 years, I'm afraid that as a very frequent SLF (it will be 24 times this year), I'm very much of the 'switch the b***** thing off - keep it off' persuasion.

Big Hilly
12th Dec 2004, 11:21
total crap . . non-precision approach gone wrong because of a mobile ? it went wrong for obvious reasons . . god bless`em Clip-clop clip-clop, oh what a surprise, it's a troll! Grow up, wotsyors! :rolleyes:

I wonder how happy those keen advocates of using 'unapproved' mobiles on aircraft would be on flying in aircraft made out of 'unapproved' parts?

BH

Lynx206
12th Dec 2004, 12:18
I left my GSM phone accidentally switched on in the cockpit one day and didn't realise until top of climb when the 'noise' started in the headset. When I looked at the phone there was no signal and definitely no chance of using it even though we were at FL350 G/S 300 over a major city. I am told that when the phones exceed about 150 knots or so the doppler effect causes havoc with the signal to and from the ground station. Is this the case?

Apologies if I have missed this earlier in the thread.

slim_slag
12th Dec 2004, 13:27
Mobiles on planes, yawn, I turn mine off.

It's mobile phone base stations sat close to the end of Cat IIIB approaches that I'm wondering about. Only one person on this thread seems to know much about radios, and it isn't me, I'm just asking questions. CarltonBrowne wins the prize for knowing less about it than me though :p

eal401
13th Dec 2004, 08:06
One notices Mr EAL has gone a little quiet
Oh I am so sorry. You see, I have this thing called "a life" and have been enjoying it over the weekend. This is something whereby you do something other than sit if front of a computer. A handful of you may be familiar with it.

Well, the mobile phone use aboard aircraft that I refered to happens every single day during the take-off and landing phases, for obvious reasons. It has been happening since the airline in question has been set up. I haven't, again for obvious reasons, named the airline, so plenty here know nothing about what they are saying. Number of incidents or crashes reported. Yep, nil. Oh and I am in a position to know thanks.

I admit this doesn't prove that it is dangerous, sorry for not being as clever as some, but I believe in this little thing called "having an opinion."

I don't appear to recall being personally abusive to anyone in this post, so quite why some comments are justified here I don't know. Still, many of you are pilots, so I guess that explains some of the reasoning.

Capt.KAOS
13th Dec 2004, 08:54
Once I forgot to switch off my GSM and we still safely arrived at destination (in a B737). Statistically thousands of passengers must have forgotten to switch of the GSM in the past and there's no indication that this has lead to a string of crashes.

I don't appear to recall being personally abusive to anyone in this post, so quite why some comments are justified here I don't know. Still, many of you are pilots, so I guess that explains some of the reasoning. This unfortunately is not entirely uncommon on Pprune, eal401.

Face the harsh reality: you are an ignorant pax, a species which in the eyes of some flygods are a necessary evil that unfortunately has to be tolerated because it funds their job/passion/hobby/lifestyle.

Once I made a simular post about these flygods and was subsequently banned, so it appears to be the norm and if you don't see me for a while after this you know da reason ;)

Cell Phone Calls In Flight? (http://money.cnn.com/2004/12/09/technology/personaltech/cellphones_inflight/)

flapsforty
13th Dec 2004, 09:14
KAOS, you're telling porkies again! ;)
The reason for your long ago....ermmmm...absence was not being impolite to pilot chappies (we could close down the whole site if we used that criterion!) but for repeatedly and willfully disregarding the JB ROE despite many gentle proddings from yours truly....

Just refreshing your memory here Your Honour.:p

Navajo8686
13th Dec 2004, 11:19
Thank you all for your combined answers - I now understand more but remain puzzled that there is so much variation over the effects of mobiles.

Regards

Navajo8686

419
13th Dec 2004, 11:28
It's probably due to there being so many variations in the condition of the wiring screening, age of wiring, nearness to the phones etc. Also, mobile phones can vary as to the transmitted power.

Does anyone have any idea of the power output of a satellite phone (iridium or similar sort of thing), and if these have ever been known to cause any problems.

419

effortless
13th Dec 2004, 11:37
Just to add a little personal experience here. I worked on the first data transmission study for cellular phones and we found that the old analogue units played havoc with all sorts of electronic equipment. Newer digital units are not so dangerous but they do give off a lot of spurious signals as do radios, laptops etc.. I spend a lot of time in hospitals and monitors can go us when the consultant hasn't turned off his mobile while in ITU.

The point is that, though the risk is low, especially when only one or two handsets are turned on, everyone has one now. Do we really want three hundred odd PAX using them in a confined space? Nevermind the chaos caused to the multiple cells that they would be logging to, that is the units would log to more than one ground unit at once. That is why it is illegal to use one in the air over the UK.

For my part, I don't want to risk it. If you can't be seperated from your phone for a few hours then there is something wrong with your life. :rolleyes:

MadsDad
13th Dec 2004, 13:23
419

I was talking to one of the engineers here. He couldn't give a specific figure, depends on phone type, but thought it would be about 24-50 DBM. However he did say it was a tightly focussed beam (more power/sq. centimetre bradcast) so a satphone would more than likely miss any wiring but, if it happened to have wiring within the beam any induced currents would be greater.

Jerricho
13th Dec 2004, 14:15
I like the bit where EAL takes the bait........

(whoops, this isn't the re-run thread.)