Phone usage during flight
 

Last November I was on AS459 seated in 2A. We had just passed 10,000ft. Captain turned off the seatbelt sign, told we can use electronic devices, the usual. Seated in 1D was a lady. After we where told we could use electronic devices she whipped out her little Verizon flip phone and started making a call! "hello?, can you hear me?!, No i'm on the plane". The FA was talking to a passenger in economy but when she saw what was happening she sprinted up to her, and told her to put it away. The lady insisted she didn't do anything wrong but anyone who paid any attention to the safety announcements knew she was wrong. I'm surprised she could even get signal up there. I wonder how many people have tried to call someone in flight?

Your cell phone selects the strongest signal from the towers that are in your area. Normally it would be the nearest one. As you move, it may select a new tower as the signal strength changes.

In a plane, the system gets confused because you are at a higher altitude and there are many more towers in range. Planes also move faster than cars on the ground. Basically, the system isn't designed for that sort of use. If you get service at all, it will be more erratic.

It's more of a service quality issue that it is safety.

There's two parts to it. First, it can really cause problems with the cell system, for the reasons already posted. Second, the FAA really doesn't like anyone using any kind of device that transmits energy (RF, etc) on an aircraft. All the systems installed on the plane are tested to make sure they don't interfere with other systems. A normally working phone might not bother anything, but a broken (or deliberately modified) one certainly could.

joe

Affecting ground communications is a concern. Affecting avionics is not. It's never been proven that cellphones interfere with avionics.

Hasn't it???

I fly light aircraft. I have, on one or two occasions, taken off with my cellphone still switched on in my pocket. The reason I noticed it was on was the fact that it interfered with the aircraft radio.

OK, I appreciate that the telephone of a passenger in seat 35A (or even 2A) is going to be a lot further away from any avionics than a telephone in the pilot's pocket.... but to claim that there is no proof that cellphones interfere with avionics is not correct. I get that proof every time I fly a light aircraft with my cellphone accidentally left on.

Depends on the definition of proven. IEEE (Institute of Electrical and Electronic Engineers) one of the authorities on electronic interference have extensive published peer reviewed research in this area. Here are a few articles. You can find more by doing a simple literature search.

Phoning and flying
Cell Phones Use in Aircraft - A Short-Term Reality?
PED Interference Reporting System in Japan
A description of the software element of the NASA portable electronic device radiated emissions investigation
Cell phone/w-lan emissions interference with narrow body aircraft communication and navigation systems

Showing that something is technically possible is not the same as showing that something is an actual risk in the real world.



However, real world experiences do have a real correlation to real world risk.

There have literally been hundreds of millions of commercial flights with billions of radiating devices (cell, bluetooth, wifi, etc...) with zero accidents attributed to them. This makes the real world risk a total of 0.0000000000%

One time my phone "turned itself" on somehow in my hand luggage and upon landing I had loads of SMS messages welcoming me to countries like Afghanistan and Iran. :)

There is a difference between a cell phone being turned on and a cell phone in active use. Use of cell phones create a significant risk of problems on board a commercial aircraft. If you really want to see air rage, permit the use of cell phones in a crowded US-domestic airliner. Everyone will be shouting over their neighbor because their conversation is so important.

^ Remember that airlines have blocked VOIP calls onboard as well.

On Sept 11, 2001, many people in the doomed airplanes pulled out their cell phones to call loved ones and say goodbye. A lot is known about what actually happened during the hijackings from cell phone communication during the events.

Begging the question: Why would Boeing, Airbus, Embraer, Fokker, etc, make multi-million dollar aircraft, only for them to be significantly impacted by a $50-$100+ device like a cell phone? [err, better phrased, why wouldn't they plan for such possibilities?]

Exactly. The prohibition on cell phone use may well be the last vestige of civility on US domestic flights. Take that away, and every excruciating cell phone conversation you've overheard on the street gets moved one foot away from your ear.

Though maybe it wouldn't be so bad if they installed signal relays onboard and charged for cell phone use, something like $5/minute (comparable to Airfone rates). At least it'd keep calls relatively rare, and bring in another revenue stream.

bolding mine: I think it has to do with altitude as I wanted to use my cell to snap a picture of a bunch of F/t'ers all on the same flight but I had to turn my phone on and then flip it into airplane mode and when i turned it on, no signal at 28,000 feet but one another flight, i was in 3c (last row of f/c) with jackets hanging behind us and no sooner did we clear 12,000 feet (listening on Ch9), a cell phone in the pocket of the jacket hanging up behind me rang with an incoming call :eek:

I dread the day, I really do, when (or if) mobile/cell phones are allowed to be used on planes. Gaudy ring tones going off all the time, inane conversations in every second seat ("No, I'm on the plane..."): I can just as well imagine it. :rolleyes: