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Cell Phone Use in Planes

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Gone Fishin'

Guess the cellphone annoyance will be everywhere now!!!

Can see a lot of possibilities for plane rage here, as many who use cell phones don't have consideration for those around them, and the whole flying thing is very sensitive anyway!!!!! Wonder if the pilots can use while flying :p ??



American, Qualcomm Test Cell Phones In Flight

In-Flight Personal Cell Phone Calls Require FAA Approval



DALLAS -- The information superhighway is about to take off into the skyway.



American Airlines and Qualcomm are teaming up on technology that will enable travelers to make phone calls from an airplane in flight using their personal cell phone.



"Now we're just gonna open up this whole thing and let everybody on this airplane place calls around the world and receive calls," said Irwin Jacobs, Qualcomm's chief executive.



Jacobs recently made the first call 25,000 feet in the air.



The quality of the calls is pretty clear, no matter how far away the person on the other end of the line is, KXAS-TV in Dallas reported.



American Airlines spokesman Monte Ford said it's all about convenience and instant communication in case of an emergency.



"[Passengers can] continue the phone call that they had or the business meeting or check on Joey," Ford said.



But in-flight cell phone usage still needs approval from the Federal Aviation Administration.



Jacobs said the approval is necessary to "make sure that all the safety agencies are comfortable, that we cannot be harming any of avionics. "



"This is the beginning of a great journey and I think the fact that entertainment and Internet access -- and cell phone usage -- is starting to at least be on the horizon [covered] with air travel. I think that's a step in the right direction," American Airlines spokesman Roger Frizzell said.



Using a personal cell phone on planes is currently banned on planes due to concerns that they could interfere with navigation systems. It will probably be another two years before it's legal to chat on a cell phone and fly, KXAS-TV reported.

Distributed by Internet Broadcasting Systems, Inc. This material may not be published, broadcast, rewritten or redistributed.
 
I always had heard that in addition to any interference it might cause on the plane, that it could have serious consequences on the cellular network. The short version was that the cell network was designed on the assumption that you would only be in line of sight of a few towers at a time. But when you put someone on a plane 6-7 miles up, you suddenly have visibility to a whole bunch of towers. And since you are travelling at a high rate of speed, you're acquiring and losing visibility to towers at a faster rate. And then the network would go nuts tracking a bunch of calls doing this same thing (technical description).



Anybody with more cellular experience that can confirm or deny this?
 
I've noticed that the few times I've left my phone on during flight (accidentally, of course), I loose signal above 10,000' or so. I don't know if it's weak signal or I hit too many towers and they lock me out.



As far as interference, I can always hear the "tic-tic-tic" of Nextels in my headset, no matter where they're at in the plane. I've had cell phones also make the lightning detector in our plane go nuts, too. Nothing else seems to be affected. But that's just our aircraft, too. I know of a case where a GameBoy really messed up the ILS receiver in an airliner (the thingy that guides the plane down to the runway through the clouds) to the point of making the system unusable. When the toy (that shouldn't even transmit RF) was turned off everything was okay again.



And I don't think the rule is an FAA thing as much as it is an FCC thing.
 
I think that the solution that is being considered for this is to install a "mico-cell" system in the aircraft, which in turn communicates witht the cell systems on the ground. Basically, your cell phone will make a connection to the airphone. Using CDMA technology, the radiated power from a cell phone should be very low when in close proximity to the cell site, and thus less likely to cause interference with the avionics systems.
 
The in flight phones are cellular, so what makes you think your personal cell phone wouldnt work?



I think its more of "force the people to use the inflight phone" rather than a technical issue.
 
The FAA is a pretty conservative bunch. From my experience, only when heck freezes over will they approve the use of cell phones in commercial planes.



Then again I may be wrong. If something does go wrong, who is going to be responsible. The person that was using the phone was the cause of the crash and they have billions at their disposal for all of the lawsuits. :-{} I don't think so. You can wait a couple of hours till you are on the ground to make you phone call(s). Nothing is that important...

Flame away.....

I have my asbestos suit on... . :)
 
Oh, this is just great. I'm really looking forward to sitting next to someone who is on the phone telling all the details of aunt Marge's operation and how little Jimmy is now potty-trained :rolleyes: , while the fast-talking nerdy-voiced guy on the other side of the aisle is saying, "Okay, now if you look at the budget projections on page two, you will see that if we maximize the net return ratio on an upward trend, the marginal basis will create a bias toward potential growth in third quarter net gains thereby maximizing maximum maximizations while minimizing minimum negative aspects. Therefore the whole projected return ratio (blah blah blah)... " :rolleyes: Then there's the high school girl in front of you saying, "Omygawd! I'm all, like, no way, and she's all 'you gotta be kidding', and, like, you know, it's like, 'what's up, girlfriend'? ... TOTALLY!" :confused: And in the meantime, a guy behind you is arguing with his wife in Spanish :-{} while the woman next to the high school girl is having a conversation in Korean, and she's being loud enough to be heard in Korea. :( And you're surrounded by all these people for 3 or 4 hours!! :{

No thanks, I'll pay for the high price of diesel just to be able to drive to my destination in peace and quiet!

Andy
 
"I think its more of "force the people to use the inflight phone" rather than a technical issue. "



Remember all of the announcements, cell phones are bad and affect the plane instruments, when in fact it may be more of a revenue issue, and now the airlines have a handle on how to make money off of it. If it works it sure would make their investment in in-flight phones a boner, unless there is more money with this technology???



But what about everyone in a commercial airliner trying to talk on a cell phone at the same time? You know how they discuss their personal problems so quietly!!!! , and you are trying for some quiet time!



". . You can wait a couple of hours till you are on the ground to make you phone call(s). Nothing is that important... "



Guess you have never heard how important some of these cell phone calls are :rolleyes: You know the 'QUIET' ones with intimate details about their date last night, spouses/boyfriends/girlfriends fighting, Aunt Bertha's gall bladder surgery, or what the found in their belly button lint, etc. :eek: Sort of like at the mall but you can't walk away. :(



My guess is that the flight attendants will have to be WWF qualified to sort through the inteference :p
 
JPope said:
Using a personal cell phone on planes is currently banned on planes due to concerns that they could interfere with navigation systems. It will probably be another two years before it's legal to chat on a cell phone and fly, KXAS-TV reported.

Distributed by Internet Broadcasting Systems, Inc. This material may not be published, broadcast, rewritten or redistributed.



That is not the reason why cell phones are banned on airplanes. The only systems that could possibly be interfered with are some of the radio systems that have not been utilized since the late 1970's on single engine personal planes.



The reason that cell phones are not allowed on planes has to do with handoff speed. When you drive around in your car, as you approach the limit of one cellular cell, your phone begins to search for a more powerful signal. If one is found, and a channel is available, a "handoff" occurs. This can be both intra and inter cell (within the BSU), within a BSC (group of towers) or MSU (Region of towers). Every time you switch cells, the cellular system has to process this, and readjust a dozen or so things. In the car, this does not happen all that often, because the radius of a cell is can range from a few hundred meters (in the city) to 20/30 km in rural areas.



If you were to use your cell phone in a airplane traveling approx 850 kmph, causing a handoff to occur approx every 35 ms. It takes the cellular structure anywhere from 2 to 6 seconds to re-register your phone in a new cell.



The reason you can not use cell phones on a plane is you will drive the cellular system crazy, and cause a possible failure. Air carriers ask you to turn off your phone as a courtesy.



If you would like more details about the different types of handoffs on the three cellular systems utilized in the US, please ask.



-Rich
 
rkressg said:
The reason you can not use cell phones on a plane is you will drive the cellular system crazy, and cause a possible failure. Air carriers ask you to turn off your phone as a courtesy.



Good, so I'm not crazy. I was starting to think that I didn't actually hear this anywhere and just made it up one time after a few drinks. :D
 
Like the others said, too high or too fast will cause problems with the cell system and the phone just won't work.



On the other hand, low and slow, the phone works just fine. Say a cessna 172 at 3000 ft. works just fine. aviation intercoms and headsets are made to interface with the phones really well now. I think its still illegal according to the FAA. Never asked them and I'm not going to. Let them pull me over and check.



John
 
Of note, cellular towers are not designed to carry the signal over 40 miles at a height more than 3000 ft above the tower top. As for inflight phones being "cellular", that's not the case... they use "other means" of transmission. Some use satellite and others use antennae to ground entry point systems, not the commercial cellular towers that you see around the countryside. I could fill you in on the details of how I know this information, but then I'd have to have you terminated:D:D:D.



For real, I'm a 747 Instructor Pilot, on a plane that does communication for a living. And the previous statement about interference on instruments is correct. None of the current cellular frequencies operate in the spectrum of modern avionics that can be interefered with.



Cheers,



Loren
 
I was at an FAA seminar last month and one of the FAA people had a presentation on use of cell phones (using an airborne "pico-cell tower") in airplanes. He also talked about wireless internet being implemented in airplanes. I have a copy of the presentation at work, and hope to scan it and post it on my website. When I do so, I'll post a link here. He had graphs and numbers from case studies of reports of cell phone interference. While reported cases were rare, there were some cases. One example that he mentioned was a cell phone in luggage in the belly of the A/C setting of a smoke/fire detector in the baggage compartment. This caused a warning light in the cockpit, so the flight crew made an unscheduled landing (don't know if it was considered an emergency landing) to deterimine the cause. Keep in mind that cell phones transmit with to the cell system even when you are not having a conversation so that the cell system knows where you are.



I am speculating that what will be implemented will be a "pico cell tower" on-board the aircraft. Your cellphone will connect through the on-board system, and then to the ground. That being the case, I would expect that you will pay significant roaming charges to use the system, which would severly limit the number of soccer moms from using it. Basically, they will replace the seat-back in-flight-phone hand sets with your personal cell phone, but the rest of the system may very well use existing airborne telephone technology.
 
The budget aviation cell phones (okay, so budget and aviation don't really go together) do actually use parts of the cell tower network. There's a handful of cell towers (approx 135 in the US) that have horizontally polarized antennas in addition to the normal vertically polarized terrestrial antennas, and they plug right into the normal cell network. But there's not many of these systems being installed any more since satcom has come down in price significantly in the past few years.



The FAA doesn't specifically ban cell phones. FAR 91. 21 leaves it up to the operator of the aircraft to decide what "portable electronic devices" may be used on the craft. But if you turn it on after the flighcrew tells you to turn it off, then you're breaking the law.



But the FCC specifically says no:

Federal Communications Commission (FCC) regulation 47 CFR Ch. 1 (10/01/98 Edition) says: Section 22. 925 Prohibition on airborne operation of 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.
 
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