Why are cell phones banned on airlines?

[dave rogers]

I honestly don't understand. I know the reason is a good one, I'm just curious.

[Samm]

Yes it is a damned good reason... because people talking on cell phones are a damned nuisance!

Can you imagine suffering through a 3 hr flight with half the people on the plane chatting away about their mundane little lives while you are just trying to survive the cramped space they call a seat? Hell... its bad enough when just one person does that in a crowded situation.

[LouC]

I honestly don't understand. I know the reason is a good one, I'm just curious.

You don't understand but you know the reason is a good one?

Yes you are curious.

They allow their use before flight and after landing.

That is too much in my opinion.

God if I had to listen to a hundred inane cell phone conversations on a flight someone would end up dead by the time we landed.

There is no reason to use them, with the possible exception being to annoy the hell out of other passengers.

[gb2004]

You don't understand but you know the reason is a good one?

Yes you are curious.

They allow their use before flight and after landing.

That is too much in my opinion.

God if I had to listen to a hundred inane cell phone conversations on a flight someone would end up dead by the time we landed.

There is no reason to use them, with the possible exception being to annoy the hell out of other passengers.

:))

[dave rogers]

Your right about it would be a nuiscance. I thought it was a "safety" thing.

[LouC]

Your right about it would be a nuiscance. I thought it was a "safety" thing.

The original electronics bans were attributed to possible interference with cockpit communications with towers if I remember correctly.

The safety issue I do believe I covered.

If they were allowed to be used during the flight someone is bound to end up dead.

[MikeJF]

the real reason is: money

Exactly how a cell phone interferes with airline electronics is not completely known and would cost a LOT of money to research the issue. Once a lot of money was spent on research, then a lot more money would have to be spent retrofitting all airlines as needed, if needed.

The ban simply avoids this expense. It's also more desirable for the airline to not have passengers communicating with the outside world, especially when a crises situation develops. I also heard that cell phone companies also say cell phone towers are designed for cell phones to operate underneath the towers, not above them. Another expense to get that to work properly.

[gdoane]

The main problem is that the cell phone is a radio which affiliates (tries to anyway) with cell phone towers. Put that cell phone up thousands of feet where it can see dozens of towers and it's going to go nuts transmitting to try and find a decent cell site.

If you look at a cell site antenna array, you notice it doesn't point upwards, but rather outwards in three (usually) directions. In a high place like an airplane, that means optimal signal is going to be line of sight with the horizon, not necessarily the closest cell tower and that introduces another problem.

The cell phone has a "window of opportunity" in which it's supposed to communicate with the cell tower, and because of speed of light limitations the window comes up to be something like 120 miles before the cell phone's timing is just too far off from the tower to make the window. Therefore, when a cell phone sees a tower line-of-sight over about 100 miles away, it tries and tries and tries (they're stubborn that way) to get into the too-distant cell site but it can't do it.

These retries can cause transmitting that could potentially interfere with avionics and communications system aboard the craft and while most probably wouldn't do much more than just run the cell phone battery down to nothing and die, if one does go crazy and start interfering with systems it would be very difficult to track down and elminate.

The main benefit to you as a consumer is that your poor cell phone won't be running the battery down trying to catch cell sites and the main benefit to the airline is there's not some little radio going nuts because it hears a bunch of cell sites that it just can't talk through potentially interfering with aircraft elex.

[dave rogers]

The main problem is that the cell phone is a radio which affiliates (tries to anyway) with cell phone towers. Put that cell phone up thousands of feet where it can see dozens of towers and it's going to go nuts transmitting to try and find a decent cell site.

If you look at a cell site antenna array, you notice it doesn't point upwards, but rather outwards in three (usually) directions. In a high place like an airplane, that means optimal signal is going to be line of sight with the horizon, not necessarily the closest cell tower and that introduces another problem.

The cell phone has a "window of opportunity" in which it's supposed to communicate with the cell tower, and because of speed of light limitations the window comes up to be something like 120 miles before the cell phone's timing is just too far off from the tower to make the window. Therefore, when a cell phone sees a tower line-of-sight over about 100 miles away, it tries and tries and tries (they're stubborn that way) to get into the too-distant cell site but it can't do it.

These retries can cause transmitting that could potentially interfere with avionics and communications system aboard the craft and while most probably wouldn't do much more than just run the cell phone battery down to nothing and die, if one does go crazy and start interfering with systems it would be very difficult to track down and elminate.

The main benefit to you as a consumer is that your poor cell phone won't be running the battery down trying to catch cell sites and the main benefit to the airline is there's not some little radio going nuts because it hears a bunch of cell sites that it just can't talk through potentially interfering with aircraft elex.
That was highly informative. thanks alot.

[dave rogers]

The original electronics bans were attributed to possible interference with cockpit communications with towers if I remember correctly.

The safety issue I do believe I covered.

If they were allowed to be used during the flight someone is bound to end up dead.
lol I can't say I disagree with you.

[sgdp]

I am SERIOUSLY not a 9-11 nut.

But is it even possible to make phone calls from those heights?

[Tulsa]

The main problem is that the cell phone is a radio which affiliates (tries to anyway) with cell phone towers. Put that cell phone up thousands of feet where it can see dozens of towers and it's going to go nuts transmitting to try and find a decent cell site.

If you look at a cell site antenna array, you notice it doesn't point upwards, but rather outwards in three (usually) directions. In a high place like an airplane, that means optimal signal is going to be line of sight with the horizon, not necessarily the closest cell tower and that introduces another problem.

The cell phone has a "window of opportunity" in which it's supposed to communicate with the cell tower, and because of speed of light limitations the window comes up to be something like 120 miles before the cell phone's timing is just too far off from the tower to make the window. Therefore, when a cell phone sees a tower line-of-sight over about 100 miles away, it tries and tries and tries (they're stubborn that way) to get into the too-distant cell site but it can't do it.

These retries can cause transmitting that could potentially interfere with avionics and communications system aboard the craft and while most probably wouldn't do much more than just run the cell phone battery down to nothing and die, if one does go crazy and start interfering with systems it would be very difficult to track down and elminate.

The main benefit to you as a consumer is that your poor cell phone won't be running the battery down trying to catch cell sites and the main benefit to the airline is there's not some little radio going nuts because it hears a bunch of cell sites that it just can't talk through potentially interfering with aircraft elex.

Yet that does not stop them from offering (for a hefty fee) me to use that phone they conveniently placed in the back rest of the seat ahead of me.

[gdoane]

Yet that does not stop them from offering (for a hefty fee) me to use that phone they conveniently placed in the back rest of the seat ahead of me.

My helo pilot carries a satellite phone from the old Iridium system. Satellite phones don't care so much about altitude, but they're very expensive. They work, but as you've noted, they come with a hefty fee.

[gdoane]

I am SERIOUSLY not a 9-11 nut.

But is it even possible to make phone calls from those heights?

The 9-11 jets were flying very low, and it's possible. The tallest radio site I work on is a bit over 7,000 feet altitude and cell phones work fine there. They should, there's a cell phone site not even a quarter mile away.

[notluzn]

I wish Wireless worked upo there

[sgdp]

The 9-11 jets were flying very low, and it's possible. The tallest radio site I work on is a bit over 7,000 feet altitude and cell phones work fine there. They should, there's a cell phone site not even a quarter mile away.

Okay. That was the one thing that always confused me. I've looked at my phone and it shows no signal when I'm flying.

But I guess if it's that low already, that makes more sense.

[DLaw911]

Yes it is a damned good reason... because people talking on cell phones are a damned nuisance!

Can you imagine suffering through a 3 hr flight with half the people on the plane chatting away about their mundane little lives while you are just trying to survive the cramped space they call a seat? Hell... its bad enough when just one person does that in a crowded situation.I could not agree more. And cell phone users tend to take constructive posssession of the air space within 100 feet around them by talking 3 tiems as loud as anyone else. How many times have you heard a person on a cell phone literally yelling, "It's noisy in here can you speak louder."

Part of the problem is cell phones, unlike traditional phones, are not duplex in nature. You don't hear your own voice in the ear piece. So thus people have a natural tendency to speak louder.

The last time I was on a phone and the plane was about to take off several people were still chatting away. I guess the flight attendant somehow notified the pilot who made an announcement that they were going to sit on the runway as long as necessary until everyone turned off their cell phones. Finally passengers began yelling at others to turn off their phones.

I often wonder how these people managed to survive without cell phones.

[DLaw911]

You don't understand but you know the reason is a good one?

Yes you are curious.

They allow their use before flight and after landing.

That is too much in my opinion.

God if I had to listen to a hundred inane cell phone conversations on a flight someone would end up dead by the time we landed.

There is no reason to use them, with the possible exception being to annoy the hell out of other passengers.Just like cell phones in theatres. Places where YOU pay for enjoyment, or for travel, to get away from the hussle and bustle of everyday life, only to have to put up with ringing phones and people talking about NOTHING. I have never heard a cell phone user talking about "sell the stock now" or in fact talk about anything that cannot wait. A few months ago I had a near fight with a cell phone user in a theatre who took one phone call after another (probably in excess of 20 calls). He would answer the phone telling some people he would call them back. For the others he would stand up, continue talking, and make his way down the crowed aisle to talk along the wall, while everyone was watching, and while everyone was still bothered by his talking. I finally yelled at him to shut off his "explitive" phone and people applauded.

Probably the worst offenders are those with walkie-talkie phones so you get to hear BOTH sides of the convesation. To me that should be a capital offense in a theatre or on an airliner.

[MrShotShot]

I think the main reason they ban their use is so I don't rip the folding tray off of the seat in front of me six hours into the flight and beat the 17-year-old to death sitting next to me.

[PuckHappy]

Well, if you were allowed to use your cell and you happen to have "Verizon" then who would be responsible for buying all the extra seats for your "people"? And what if the flight is oversold, who takes the invol? It's just easier to say no phones! :))

http://indychristian.com/images/verizon_network.jpg

[RWReaganfan]

Have you ever placed your cell phone next to your TV or computer?

If my cell is on the desk in front of my computer, the computer will "buzz" a few seconds BEFORE my phone rings. The same with TVs.

Imagine that kind of interference with aircraft avionics.

[PuckHappy]

Have you ever placed your cell phone next to your TV or computer?

If my cell is on the desk in front of my computer, the computer will "buzz" a few seconds BEFORE my phone rings. The same with TVs.

Imagine that kind of interference with aircraft avionics.

This is true. And if you look back to 9/11, which of the four planes went down before reaching it's target? The plane in which everyone was on their cell phone. :think:

[gdoane]

Have you ever placed your cell phone next to your TV or computer?

If my cell is on the desk in front of my computer, the computer will "buzz" a few seconds BEFORE my phone rings. The same with TVs.

Imagine that kind of interference with aircraft avionics.

That sounds like an old iDen (Nextel/Motorola) phone. Those were notorious for their data packet burst transmissions getting into other electronics. There was a case where one set off a smoke detector, blasted the room with FM-200 fire suppressant and caused the building to be evacuated. You don't see iDen much anymore these days.

The thing to think about interference-wise isn't that the phones just interfere with the airplane's avionics. They're interfering with other phones on the ground, too.

Usually, cell phone sites are engineered so that the frequencies are geographically seperated, because you don't want one cell phone tower getting misdirected transmissions from another cell phone tower's affiliates.

But high-flying cell phones make the geographical seperation a moot point, as they can see for hundreds of miles and transmit that far too, making efforts to mitigate cochannel interference moot if they're on and in the air.

It doesn't take much power for line of sight comms. I worked air traffic comms in the US Navy, and 5 watts is PLENTY to hit a Navy Jet Fighter from a hundred miles out for radio comms because there's just nothing in between the antennas.

That works as a blessing and a curse because interference becomes a serious possibility. That's why aircraft communications use the AM (Amplitude Communications) mode of transmission, to avoid the FM Capture Effect which could mute an important communication (say, an SOS distress call).

Cell phones at high altitude can lead to dropped calls on the ground too, which is probably why cell phone companies don't press the issue about allowing cell phones to be used in flight. Interference hurts them too.

[MrShotShot]

That sounds like an old iDen (Nextel/Motorola) phone. Those were notorious for their data packet burst transmissions getting into other electronics.

I've never had a cell phone NOT create that kind of interference - my 6 month old Blackberry does it. I can't have my computer speakers on or be on the phone if my blackberry is close by.

[sgdp]

Second that.

Every phone I've ever had does the buzzing.

[sircharliebrown]

My Blackberry Pearl buzzes if it's close to the baby monitor, but nothing else. My husband Dash does it in the car when it's sitting in the slot above the stereo.

[Samm]

the real reason is: money

Exactly how a cell phone interferes with airline electronics is not completely known and would cost a LOT of money to research the issue. Once a lot of money was spent on research, then a lot more money would have to be spent retrofitting all airlines as needed, if needed.

The ban simply avoids this expense. It's also more desirable for the airline to not have passengers communicating with the outside world, especially when a crises situation develops. I also heard that cell phone companies also say cell phone towers are designed for cell phones to operate underneath the towers, not above them. Another expense to get that to work properly.

Passengers on Flight 93 used their cell phones to call their loved ones... clearly they work in the air.

[Samm]

I could not agree more. And cell phone users tend to take constructive posssession of the air space within 100 feet around them by talking 3 tiems as loud as anyone else. How many times have you heard a person on a cell phone literally yelling, "It's noisy in here can you speak louder."

Part of the problem is cell phones, unlike traditional phones, are not duplex in nature. You don't hear your own voice in the ear piece. So thus people have a natural tendency to speak louder.

The last time I was on a phone and the plane was about to take off several people were still chatting away. I guess the flight attendant somehow notified the pilot who made an announcement that they were going to sit on the runway as long as necessary until everyone turned off their cell phones. Finally passengers began yelling at others to turn off their phones.

I often wonder how these people managed to survive without cell phones.

I was on a flight once where they pulled back to the gate and took a woman off the plane for using her cell phone after the "phones off" order. We were delayed about 45 minutes while they went through the cargo hold to find and remove her luggage.

[Samm]

Just like cell phones in theatres. Places where YOU pay for enjoyment, or for travel, to get away from the hussle and bustle of everyday life, only to have to put up with ringing phones and people talking about NOTHING. I have never heard a cell phone user talking about "sell the stock now" or in fact talk about anything that cannot wait. A few months ago I had a near fight with a cell phone user in a theatre who took one phone call after another (probably in excess of 20 calls). He would answer the phone telling some people he would call them back. For the others he would stand up, continue talking, and make his way down the crowed aisle to talk along the wall, while everyone was watching, and while everyone was still bothered by his talking. I finally yelled at him to shut off his "explitive" phone and people applauded.

Probably the worst offenders are those with walkie-talkie phones so you get to hear BOTH sides of the convesation. To me that should be a capital offense in a theatre or on an airliner.

I have a solution that should make everyone happy... The Airlines could charge everyone who simply must use their cell phones $100 per minute and share the money equally among those passengers who do not use a phone during the flight. ;)

[gdoane]

Passengers on Flight 93 used their cell phones to call their loved ones... clearly they work in the air.

On "flights" like that they will because they're low altitude and relatively low speed.

You don't have the doppler effect of full speed, you don't have the altitude problem of height above average terrain bringing distant towers into the line of sight comms, and besides, almost certainly not all cell phones worked on Flight 93.

My cell phone works fine flying low and slow in a helicopter doing about 160 MPH at an altitude of 2,000 feet. That's not really a problem, but when you start talking about 600 MPH at 20,000 feet, that's a lot different.

The 9-11 jets were not flying normally. They were trying to hit targets on the ground which is not typical jet flight pattern. The cell phones worked because they were near their working environment. Another mile high and they wouldn't work the same at all.

[Samm]

That sounds like an old iDen (Nextel/Motorola) phone. Those were notorious for their data packet burst transmissions getting into other electronics. There was a case where one set off a smoke detector, blasted the room with FM-200 fire suppressant and caused the building to be evacuated. You don't see iDen much anymore these days.

The thing to think about interference-wise isn't that the phones just interfere with the airplane's avionics. They're interfering with other phones on the ground, too.

Usually, cell phone sites are engineered so that the frequencies are geographically seperated, because you don't want one cell phone tower getting misdirected transmissions from another cell phone tower's affiliates.

But high-flying cell phones make the geographical seperation a moot point, as they can see for hundreds of miles and transmit that far too, making efforts to mitigate cochannel interference moot if they're on and in the air.

It doesn't take much power for line of sight comms. I worked air traffic comms in the US Navy, and 5 watts is PLENTY to hit a Navy Jet Fighter from a hundred miles out for radio comms because there's just nothing in between the antennas.

That works as a blessing and a curse because interference becomes a serious possibility. That's why aircraft communications use the AM (Amplitude Communications) mode of transmission, to avoid the FM Capture Effect which could mute an important communication (say, an SOS distress call).

Cell phones at high altitude can lead to dropped calls on the ground too, which is probably why cell phone companies don't press the issue about allowing cell phones to be used in flight. Interference hurts them too.

Question: Is the aluminum fuselage of an airplane fairly transparent to cell phone frequencies? I have noticed that some steel shelled buildings are nearly cell phone proof.

[Samm]

On "flights" like that they will because they're low altitude and relatively low speed.

You don't have the doppler effect of full speed, you don't have the altitude problem of height above average terrain bringing distant towers into the line of sight comms, and besides, almost certainly not all cell phones worked on Flight 93.

My cell phone works fine flying low and slow in a helicopter doing about 160 MPH at an altitude of 2,000 feet. That's not really a problem, but when you start talking about 600 MPH at 20,000 feet, that's a lot different.

The 9-11 jets were not flying normally. They were trying to hit targets on the ground which is not typical jet flight pattern. The cell phones worked because they were near their working environment. Another mile high and they wouldn't work the same at all.

Flight 93 had reached its cruising altitude of 35,000 feet when the hijackers took over.

[AeroEngineer]

Yes it is a damned good reason... because people talking on cell phones are a damned nuisance!

Can you imagine suffering through a 3 hr flight with half the people on the plane chatting away about their mundane little lives while you are just trying to survive the cramped space they call a seat? Hell... its bad enough when just one person does that in a crowded situation.



This^


Also, cell phones can POTENTIALLY cause instrument interference, though IMO the risk in most cases would be minimal. Have you ever had your cell phone positioned by a speaker system/computer and have the device make weird noises right before your cellphone rings? That same effect could mess with aircraft systems.

Also, would a cell phone even get reception at 35k feet above cell towers? I thought the antennae don't point that way?

[PuckHappy]

Passengers on Flight 93 used their cell phones to call their loved ones... clearly they work in the air.

Like I eluded to in a pervious post, Flt 93 was brought down before reaching it's intended target. We will never know what really brought it down. We want to believe that it was the "Let's roll" charge. But maybe it was the many cell phones that were in use all at the same time.
I really do not want to take that chance and allow cell ph usage on board any a/c.

[DLaw911]

I have a solution that should make everyone happy... The Airlines could charge everyone who simply must use their cell phones $100 per minute and share the money equally among those passengers who do not use a phone during the flight. ;)They could not pay me $100 per minute to sit next to some JERK who is disturbing my peace. I would rather have a screaming baby sitting next to me on a flight them some loudmouth letting the entire plane hear his sexual outbusts, the F word, the S word, everything that is purely personal and none of my business. Nothing I want to hear, nothing I appreciate. I don't want to know who dumped who, I don't want to hear, "I love you, I miss you, what are you having for dinner, what are you doing tonight, put daddy on, put Auntie Sally on, etc." I WANT a screaming baby if for no other reason to drown out the selfish punks with the cell phones that are polluting my mind. And if you think I'm joking I'm not. These people need to get a life and respect others. They need to HOLD it until they get off the plane. If the phone call is ALL THAT important, than screw the flight!! They should not travel. and if they CAN afford $100 per minute I guarantee you the conversation is going to be worthless air pollution.

[Sinister Rouge]

Maybe because it is the airlines property, not the public sector, and they have the right to make their own rules?
Just enjoy your flight, its one of the few places where you won't be bothered by cell phones.

[altair1013]

I just hope to God that they stay banned. I can't imagine being trapped in a sardine can for three hours with 20 babbling idiots.

[gdoane]

Question: Is the aluminum fuselage of an airplane fairly transparent to cell phone frequencies? I have noticed that some steel shelled buildings are nearly cell phone proof.

Well, that depends on the cell phone frequencies. Most cell phones are dual band and some are tri-band. Basically, radio waves will penetrate metal less than 1/4 wavelength. At the 800 MHz band, that's about 4 inches thick. That's not plane material, that's full metal armor.

[Samm]

Like I eluded to in a pervious post, Flt 93 was brought down before reaching it's intended target. We will never know what really brought it down. We want to believe that it was the "Let's roll" charge. But maybe it was the many cell phones that were in use all at the same time.
I really do not want to take that chance and allow cell ph usage on board any a/c.

Cell phones may have the potential to interfere with communications and navigation systems, not flight controls...

Actually... there is no evidence of any safety problem at all.

A 1996 study commissioned by the U.S. Federal Aviation Administration looked at thousands of flight records and failed to find a single instance in which equipment was affected by a wireless phone. The study was conducted by RTCA Inc., a nonprofit organization that sets industry standards for airplane electronics.

Plane makers Boeing Co. and Airbus Industrie have bombarded their aircraft with cell-phone frequencies and discovered no interference with communication, navigation or other systems. One likely reason that no problems were found: cellular phones don't operate on any of the frequencies used by airplane systems.


http://news.zdnet.com/2100-9595_22-95986.html

And some airlines have allowed cell phones ... Air France, Air Emirates and Malaysia Air all allow cell phone use.

[Samm]

This^


Also, cell phones can POTENTIALLY cause instrument interference, though IMO the risk in most cases would be minimal. Have you ever had your cell phone positioned by a speaker system/computer and have the device make weird noises right before your cellphone rings? That same effect could mess with aircraft systems.

Also, would a cell phone even get reception at 35k feet above cell towers? I thought the antennae don't point that way?

Yeah... wouldn't you love to be sitting on a plane with 100 people all loudly saying "can you hear me now?" ;)

[gdoane]

Cell phones have the potential to interfere with communications, not flight controls...

Most plane flights run on autopilot, which is computer control. Screw up the computer and you could conceivably crash the plane.

Initial reports of the French plane that crashed last month (Airbus A332, France Air, June 1st) were that electrical failures caused the captain to take manual control, and the problem with that is an Airbus at cruising speed and altitude is very, very tricky to fly manually because there's a narrow powerband which the plane has to stay within at altitude in order to maintain lift for flight. Go too fast and the engines lose power, go too slow and the engines lose power too.

The autopilot can do it, but if the plane has no autopilot then the controls are taxing on a human pilot because it takes concentration on both altitude and airspeed to maintain the powerband of the engines. Failure can (did, apparently) result in an irrecoverable condition resulting in a plane crash.

It doesn't take much to crash a plane.

[Samm]

Most plane flights run on autopilot, which is computer control. Screw up the computer and you could conceivably crash the plane.

Initial reports of the French plane that crashed last month (Airbus A332, France Air, June 1st) were that electrical failures caused the captain to take manual control, and the problem with that is an Airbus at cruising speed and altitude is very, very tricky to fly manually because there's a narrow powerband which the plane has to stay within at altitude in order to maintain lift for flight. Go too fast and the engines lose power, go too slow and the engines lose power too.

The autopilot can do it, but if the plane has no autopilot then the controls are taxing on a human pilot because it takes concentration on both altitude and airspeed to maintain the powerband of the engines. Failure can (did, apparently) result in an irrecoverable condition resulting in a plane crash.

It doesn't take much to crash a plane.

I edited that post... read the link that I added. The frequencies used by all of the aircraft operations including the fly-by-wire aircraft, are nowhere near the frequencies used by cell phones and other common individual electronics devices. Exhaustive tests have failed to produce any interference by phones, ipods or laptop computers, etc. Electronics are all subject to failure, but there is no indication that the ban on on-board use of such devices as a potential cause of said failures is factually justified.

The nuisance factors though are entirely valid.

[gdoane]

I edited that post... read the link that I added. The frequencies used by all of the aircraft operations including the fly-by-wire aircraft, are nowhere near the frequencies used by cell phones and other common individual electronics devices. Exhaustive tests have failed to produce any interference by phones, ipods or laptop computers, etc. Electronics are all subject to failure, but there is no indication that the ban on on-board use of such devices as a potential cause of said failures is factually justified.

The nuisance factors though are entirely valid.

You can't go by the final frequency in a superheterodyne transceiver.

I had a problem with a 6 Ghz (that's 6,000 Mhz) digital microwave getting flaky and I had my service monitor out using the O'scope when the autofinder went SCREAMING to a frequency near 150 Mhz (that's about 5,800,000,000 Hz away) sending digital pages. Turned out there was a digital pager radio on the same site blasting 1,000 watts dead on the IF (Intermediate Frequency) of that particular radio. It was nowhere near the frequency but it was dead on the second IF.

You can think you're a million kilocycles away and still be dead on interfering. I've seen it happen.

[djdudley]

Not for nothing, but I hate being a captive audience to some idiot on a cell phone in a plane. Could you imagine several people on their phones at one time! Nooooooooooo please!!!

[Samm]

You can't go by the final frequency in a superheterodyne transceiver.

I had a problem with a 6 Ghz (that's 6,000 Mhz) digital microwave getting flaky and I had my service monitor out using the O'scope when the autofinder went SCREAMING to a frequency near 150 Mhz (that's about 5,800,000,000 Hz away) sending digital pages. Turned out there was a digital pager radio on the same site blasting 1,000 watts dead on the IF (Intermediate Frequency) of that particular radio. It was nowhere near the frequency but it was dead on the second IF.

You can think you're a million kilocycles away and still be dead on interfering. I've seen it happen.

Still... NO actual problem has ever been identified.

[SabercatPuck]

It is also possible that the only reason that they were able to use the phones was that at the time they were close enough to Pittsburgh to be able to pick off cell towers. Can you imagine the handoff rate those things must have at 500+ MPH, and pointed somewhere other than where they are supposed to go. Cell towers have a fairly directional nature, they are designed to go out more than up, and even that is tuned to provide zones, in city closer together, in the country further appart.
That said, I would also agree that there is very minimal chance of cell phones interfering at all, much less enough to bring down a plane, but in the interest of safety and sanity (and considering the extra number of irritated people that it would create, that could be considered a matter of public safety too) of the people, the ban is in place.
As for the question of if you can use a cell phone from inside a plane, I have done it frequently. Typically right after landing the crew will announce that you can now use phones, and I have yet to not be able to make a call at that point.

[NascarGirl2448]

This is true. And if you look back to 9/11, which of the four planes went down before reaching it's target? The plane in which everyone was on their cell phone. :think:

Yeah because the people on that plane knew what was going on and fought the terrorists, causing the terrorists to crash the plane before someone who knew what they were doing landed the plane safely.

[gdoane]

Still... NO actual problem has ever been identified.

True enough, but it's kind of hard to do forensic investigation on the cause of equipment failure when the equipment is in a smoking crater too. Cell phones are incredibly frequency agile, they go to whichever frequency the cell tower tells them to so you'd almost never know which frequencies were in use at the moment of the crash.

I don't think the FAA would ever allow it anyway because they're really... inflexible.

For example, watching a helo pilot light up an A-star helo, I saw him kick on the pitot tube heater. Now, this is Phoenix, Arizona in JULY. It's 110° in the shade, and he's kicking on a heater? So I asked him about it and got this for an explanation...

The pitot tube is for measuring airspeed and the pitot tube heater is to keep ice from forming in the tube, blocking the flow of air and keeping the pitot tube from reading airspeed. The helicopter, in FAA acceptance tests, had the heater on so the pilots flying this thing have to turn on the pitot tube heater to comply with FAA regulations and the temperature doesn't matter.

I think it's nuts but in things concerning flight, the FAA makes the rules. I'd say if you're in Phoenix, AZ in July and you're worried about ice forming that you're beyond paranoid myself.

[PuckHappy]

Maybe because it is the airlines property, not the public sector, and they have the right to make their own rules?
Just enjoy your flight, its one of the few places where you won't be bothered by cell phones.

I do believe that you hit the nail on the head! When it comes down to it the airlines are run by total control freaks!
Think about it. They control the flt schedule, the price, take off and landing times (delays or closing the a/c door early). And then when you are in the air they tell when and where to sit, when to put your tray up and seat back forward, when you can and cannot use the restroom, what can or cannot go under the seat in front of you.
Even after you land and the plane is at the gate, you cannot deplane until the gate agent pulls up the jet bridge and the f/a opens the door and gives you the go ahead!

So yeah! In all reality, I'd say it is just a control thing on the airlines part. :))

[Samm]

True enough, but it's kind of hard to do forensic investigation on the cause of equipment failure when the equipment is in a smoking crater too. Cell phones are incredibly frequency agile, they go to whichever frequency the cell tower tells them to so you'd almost never know which frequencies were in use at the moment of the crash.

I don't think the FAA would ever allow it anyway because they're really... inflexible.

For example, watching a helo pilot light up an A-star helo, I saw him kick on the pitot tube heater. Now, this is Phoenix, Arizona in JULY. It's 110° in the shade, and he's kicking on a heater? So I asked him about it and got this for an explanation...

The pitot tube is for measuring airspeed and the pitot tube heater is to keep ice from forming in the tube, blocking the flow of air and keeping the pitot tube from reading airspeed. The helicopter, in FAA acceptance tests, had the heater on so the pilots flying this thing have to turn on the pitot tube heater to comply with FAA regulations and the temperature doesn't matter.

I think it's nuts but in things concerning flight, the FAA makes the rules. I'd say if you're in Phoenix, AZ in July and you're worried about ice forming that you're beyond paranoid myself.

That is not paranoia... icing is a result of dew point not air temperature. If the air is near saturation... and that can easily happen at altitude even though the relative humidity on the ground is below 10% say... it can freeze in the carburetor venturi or an airspeed pitot tube. I personally have encountered carburetor ice in the summer at ambient temperatures far above freezing. Turning on the heater may not be necessary, but if you wait until you realize that you have icing the heater may not resolve it quickly enough to prevent a serious problem. Pitot tube and carburetor heat is meant to be a preventive measure not a problem resolution measure. It is no less ridiculous on your check list than lowering the landing gear.