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From a recent AOPA email:

Question: If I am on a cross-country flight and running a little behind, is it OK to use my cell phone in flight to notify my friends?

Answer: FAR 91.21 prohibits pilots operating under IFR from using any portable electronic device while in flight. And the FCC has a regulation that prohibits the use of a cell phone on any aircraft in flight. Specifically, FCC Rule 22.925 states, "Cellular telephones installed in or carried aboard airplanes, balloons, or any other type of aircraft must not be operated while such aircraft are airborne." So, using a cell phone?whether VFR or IFR?is prohibited in flight.



Who knew?
 
Guess that means no more portable GPS for situation awareness, no more electronic flight bags, no more digital watches.....
 
Regarding portable electronic devices, you forgot to mention paragraph (b):

(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 operator of the aircraft has determined will not cause interference with the navigation or communication system of the aircraft on which it is to be used.

So, other than cell phones, you the pilot can say what can or cannot be used.

Tracy.
 
thallock said:
Regarding portable electronic devices, you forgot to mention paragraph (b):

(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 operator of the aircraft has determined will not cause interference with the navigation or communication system of the aircraft on which it is to be used.

So, other than cell phones, you the pilot can say what can or cannot be used.

Tracy.
Click to expand...

Ah sweet... I can still shave... :D
 
WHAT...

YOU SAY I CAN USE MY HEARING AID ON WEDNESDAY?

NO, THURSDAY!

YEAH, ME TOO. LET'S GET A BEER.
 
E mail

So here is a dumb question. If I have a wireless card in my Laptop and I have a signal can a passenger send an email or a text?
 
no email

i would lean towards no.

those wireless cards are designed to access cell networks like a cell phone... so if a hazard exists with cell phones interfering with NAV/COM, it would be safe to assume that the wireless card is creating the same kind of interference.
 
rodcritt said:
So here is a dumb question. If I have a wireless card in my Laptop and I have a signal can a passenger send an email or a text?
Click to expand...
Rodney,

I always try to send a text message from y cell phone when in flight to let the people I'm going to visit know my ETA. However, the messages don't always go through. It is kind of hit or miss.

When flying over the mountains, I seem to have better luck for some reason but when the terrain is flat, not so much.

From what I understand, it all has to do with the design of the cell towers and how the signals are designed to radiate out and down, not up.
 
But why ?

Just curious, is there any hard data to indicate that cell phones cause a problem with the airplane avionics. Somewhere I read that the real reasons were more commerical such as:

Commercial Airlines had phone service for sale in flight for something like $8 a minute. Remember the in-seat phones?

Commercial Airlines didn't want everyone talking on phones yelling "can you hear me now"! Thank you thank you thank you

Also might have had something to do with phones possibly hitting multiple towers and clogging things up?


Have no idea if any of that is true but I am REALLY glad you can't use them in the air on commercial flights ;-) but I have never seen any hard data on what a cell phone can really impact. Anyone know for sure?



Bill S
7a finishing
 
I asked an FAA buddy of mine if you can use a cel phone inflight and here is his reply..........

Larry,
It’s a good question and I don’t think I’ve ever gotten a good answer. I can’t speak for the FCC, but according to 91.21 you may be able to depending on the type of operation. It states Air Carrier or aircraft operated under IFR may not. An Air Carrier would be aircraft operating under 121, 125, 135, 137 ect. If my wife and I are out flying around in our plane, we are Air Operators under part 91 and are not flying under an Air Carrier Certificate. As long as we are not IFR, I don’t believe that we would be in violation of an FAR. However, there is the FCC side of the house. I know that there is a big problem with cell phones calling up too many towers in the air. Of course, there are a lot of headset manufactures that have added cell phone hook ups to their products. So, you can get your IFR clearance on the ground, of course!
See ya

Good enough for me, I'm using my cell phone in flight.
 
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Cell Towers

My understanding is that a cell phone (in a car) will switch from cell tower to cell tower as you travel based on signal strength. However, in an aircraft, your cell phone signal is capable of reaching several cell towers simultaneously. So, your signal is hogging several channels on many towers, cluttering up communications for others. Just something I heard, but it makes sense.
 
DUH!

Test it. If it works without screwing with your electronics, why not use it? Its only gonna work in limited areas anyway. The Feds can't locate Osama, how are they gonna find you?
 
BillSchlatterer said:
Just curious, is there any hard data to indicate that cell phones cause a problem with the airplane avionics.
Click to expand...

Couple of facts:
a) mobile telephony is a two way transmission. You can switch off the phone, you can't switch off the tower
b) tower have much stronger signal
c) towers transmit on all the channels at once, cell jumps between them, but uses only one at a time.
d) when you are in flight your plane can be in range of multiple towers
e) even if you are not talking your phone is periodically contacting towers transmitting often with full power.
f) there are several sources of HF radiation in the airplane, many of them much more powerful than cell's 0.5W so avionics should be properly shielded right?

Considering all of this I'd say using cells onboard is safe. If it's legal it's a whole different story.
 
It has been done. Probably best for passengers only, or when conditions are so good and easy to fly in that it is safe for the pilot also.

It is kind of funny when you tell someone that you are in one place at the beginning of the conversation and tell them you are a lot further down the road 5 or 10 minutes later!!! It makes them wonder what kind of an idiot you are for driving that fast!!

I guess that does not determine if you are supposed to though...
 
Cell phones in flight

I finally just gave up on cell phones in flight. Forget the legalities, its just not a reliable connection. Amazingly text messages work pretty well though. I write a text and then let the phone search for a while. It will eventually get out when it gets a quick connection.

For safety I finally just bought a Iridium phone for flight. My wife really appreciates me checking in on long flying days - particularly if I have my son with me. That works really well and if you don't use it much its not really cost prohibitive. And it can be pretty useful... ;)
 
One data point

Occasionally my wife forgets to turn off her phone while we are flying. There have been several times that I have gotten a bit of a buzzy noise in my headset when the phone rings - the spacing of the noise correlates with the ring and/or vibrate on the phone, so it is clear to me that the phone is causing the buzz in my headset. Whether this is my specific avionics setup (currently flying an old C172), I don't know, but it seems clear to me that there is potential for interference with other things (like nav instruments) as well. I would be interested to know whether anyone else has experienced this.

greg
 
The real problem with aircraft and cell phones...

Here is a report from the latest NASA ASRS Callback Report. I always knew that those things were dangerous! :)

Cell Phone Commotion
The pilot of a vintage J-3 Cub floatplane reported to ASRS that a cell phone call from a misguided golfer set in motion a law enforcement and search and rescue effort.

I aborted a landing on the southwest end of ABC Lake due to low level turbulence, windshear, and lake obstructions. At this time, I commenced on
my route of flight southward over the golf course. According to [sheriff]?during climbout/departure of the aborted landing and passage of the golf course, a golfer called emergency personnel stating that a yellow aircraft flew over the golf course with wings rocking and engine sputtering. The individual then apparently stated he believed the aircraft crashed?[Another individual], after hearing the?commotion on her scanner, witnessed a yellow floatplane land on XYZ Lake. She stated the pilot stopped to fix the propeller, and minutes later took off heading southbound.

In reality, I attempted to land in ABC Lake to relieve myself, but due to weather constraints and other parameters could not do so safely, thus aborting the landing and continuing southbound. Due to moderate turbulence, windshear and closely spaced isobars the wings were rocking the entire route of flight?I could safely maneuver my aircraft for landing at XYZ Lake?The airplane?does not have an electrical system, therefore it needs to be started by hand. This is what I was doing: starting my airplane?[not] ?fixing the propeller.? I continued on my way home, arrived safely, tied my floatplane to the dock, just as I do every time.
I never broke any FARs and operated my aircraft in a safe and responsible manner and had no mechanical issues with the airplane I was piloting. Unfortunately, a golfer with a cell phone?was the catalyst for the much wasted time of private search personnel, law enforcement officers, and many search and rescue airplanes being deployed.

John Clark
RV8 N18U "Sunshine"
KSBA
 
MYTHBUSTERS

on discovery channel, did an episode trying to bust the myth of cell phone interfering with avionics... i'm trying to find the episode now..


not that the mythbusters are conclusive evidence on which to base your life (or decisions that could ultimately risk your life), but a good, well engineered test.
:cool:
 
mythbusters

Episode 49. air date: March 15, 2006.

from www.mythbustersresults.com

Mythbusters results dot com said:
The ban on cell phones on aircraft is designed to force passengers to use the expensive in-flight phones.

BUSTED

It was found that cell phone signals, specifically those in the 800-900 MHz range, did intefere with unshielded cockpit instrumentation. Because older aircraft with unshielded wiring can be affected, and because of the possible problems that may arise by having many airborne cell phones "seeing" multiple cell phone towers, the FCC (via enforcement through the FAA) still deems it best to err on the safe side and prohibit the use of cell phones while airborne.
Click to expand...
 
I don't see a problem with cellphones "seeing" multiple towers. If they didn't, google maps wouldn't work in the phones. Googlemaps use triangulation of several towers to pinpoint the position. Maybe another one for mythbusters? :) I have heard the problem is that the cellphones can't connect high up in the air, but will continuously try to, ant therefore they are transmitting on many channels at once all the time.
 
The reason you don't want a handset to see multiple sites at the same time, is because cell sites share frequencies. It's somewhat like coloring a map with only 4 colors, no adjoining states can have the same color. Cell services re-use frequencies by insuring that adjacent cell sites don't use the same frequencies. That's actually where the name comes from, each site creates a "cell". The sites are designed so that they cannot hear a signal from two cells away. If you transmit on a single channel while airborne everyone within line of sight will hear you, tying up multiple cells.

At least that's the basic concept. Now, with the number of cell phones out there and the demand for service, they have started breaking up the cells into smaller sectors using directional antennas which apparently don't cover much above the horizon. It increases coverage on the ground, and probably helps alleviate some of the problems caused by people that don't follow federal regulations in the air.

Paige
 
Greg Arehart said:
Occasionally my wife forgets to turn off her phone while we are flying. There have been several times that I have gotten a bit of a buzzy noise in my headset when the phone rings - the spacing of the noise correlates with the ring and/or vibrate on the phone, so it is clear to me that the phone is causing the buzz in my headset. Whether this is my specific avionics setup (currently flying an old C172), I don't know, but it seems clear to me that there is potential for interference with other things (like nav instruments) as well. I would be interested to know whether anyone else has experienced this.

greg
Click to expand...
I do too. GSM technology phones (example, T-Mobile or AT&T - I have T-Mobile) are notorious for that buzzing sound. Mine does it also around almost anything with a speaker. Clock radio, various older and newer aircraft, etc... I have not seen it affect nav sources or anything in the cockpit. But it surely gets to speakers in the headphones.
 
PaigeHoffart said:
The reason you don't want a handset to see multiple sites at the same time, is because cell sites share frequencies. It's somewhat like coloring a map with only 4 colors, no adjoining states can have the same color. Cell services re-use frequencies by insuring that adjacent cell sites don't use the same frequencies. That's actually where the name comes from, each site creates a "cell". The sites are designed so that they cannot hear a signal from two cells away. If you transmit on a single channel while airborne everyone within line of sight will hear you, tying up multiple cells.

At least that's the basic concept. Now, with the number of cell phones out there and the demand for service, they have started breaking up the cells into smaller sectors using directional antennas which apparently don't cover much above the horizon. It increases coverage on the ground, and probably helps alleviate some of the problems caused by people that don't follow federal regulations in the air.

Paige
Click to expand...

As antennas get smarter, they may try to focus a beam on you. As you happen to be very far away from particular sites, that may reduce capacity for the remainder of the cell that would be serviced by that antenna. I don't know if the technology has been rolled out yet, but it is in the works. I would expect that there would be some threshold where they won't even try assuming that you are too far away.

Signaling schemes such as CDMA count on you being in sync with the base station in your cell. Once that happens, non-interference is guaranteed with other CDMA users in the vicinity. If you're hitting multiple base stations this property of CDMA is diminished. I'm not even sure what happens at the PHY level when seeing multiple sites with decent signal strength. You could be getting handed off many times per second and congesting the handoff mechanism.

Remember, just because you tried it and nothing bad happens to you, doesn't mean that nothing bad is happening.
 
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