# Cell phone use in planes **URL:** \ **Category:** Factual Questions\ **Created:** [May 7, 2001, 4:47am UTC](https://boards.straightdope.com/t/cell-phone-use-in-planes/64612 "2001-05-07T04:47:20Z")\ **Posts on this page:** 14\ **Page:** 1
**Author:** ![Tatjana](https://avatars.discourse-cdn.com/v4/letter/t/d9b06d/32.png) [@Tatjana](https://boards.straightdope.com/u/Tatjana)\ **Post date:** [May 7, 2001, 4:47am UTC](https://boards.straightdope.com/t/cell-phone-use-in-planes/64612/1 "2001-05-07T04:47:20Z")
As we were going in for our landing at JFK a couple months ago, the woman behind me got on her cell phone to make arrangements for a pick-up at the airport. She refused to hang up until she was finished, even when the flight attendants asked her to. As soon as they walked away she got right back on. Obviously, we all agree she was a really obnoxious person who deserved to be thrown out of the plane, but were we in any real danger? Could using a cell phone really mess up the pilots’ radio communication? ---
**Author:** ![sethdallob](https://avatars.discourse-cdn.com/v4/letter/s/e36b37/32.png) [@sethdallob](https://boards.straightdope.com/u/sethdallob)\ **Post date:** [May 7, 2001, 5:00am UTC](https://boards.straightdope.com/t/cell-phone-use-in-planes/64612/2 "2001-05-07T05:00:09Z")
I’m far too lazy to search, but I _know_ that this has been asked before. The short answer: no, it doesn’t interfere with navigation equipment. There was one alleged case of interference; they tried to recreate the situation (they bought the guy’s laptop, phone, etc.) and nothing. The real reason why you can’t use cellphones on planes is that it takes a lot of CellPhoneCo’s towers to bounce your call as you zoom at 500MPH, and the billing system gets whacked up, too. ---
**Author:** ![Dr.Lao](https://avatars.discourse-cdn.com/v4/letter/d/2bfe46/32.png) [@Dr.Lao](https://boards.straightdope.com/u/Dr.Lao)\ **Post date:** [May 7, 2001, 5:36am UTC](https://boards.straightdope.com/t/cell-phone-use-in-planes/64612/3 "2001-05-07T05:36:44Z")
You probably weren’t in any danger, but you can’t be sure. Cell phones aren’t built to the same standard as electronic equipment in an aircraft, so they can put out an awful lot of extranous signals. Also, they haven’t been thourghly tested with every piece of equipment in the airplane to ensure no interference. Nothing electronic could be installed in an airplane without first being subject to these tests, it seems somewhat odd to operate any device on board that hasn’t been tested. ---
**Author:** ![Daemon](https://avatars.discourse-cdn.com/v4/letter/d/c6cbf5/32.png) [@Daemon](https://boards.straightdope.com/u/Daemon)\ **Post date:** [May 7, 2001, 6:04am UTC](https://boards.straightdope.com/t/cell-phone-use-in-planes/64612/4 "2001-05-07T06:04:05Z")
My guess is that there is no real interference or danger, it’s just that they’re trying to avoid more air-rage incidents. You know, like you are sitting next to some idiot at the theater that has to answer the cell phone in the middle of the movie. At least in that case you can walk out and cool off, but where are you gonna go on an airplane? ---
**Author:** ![Tatjana](https://avatars.discourse-cdn.com/v4/letter/t/d9b06d/32.png) [@Tatjana](https://boards.straightdope.com/u/Tatjana)\ **Post date:** [May 7, 2001, 6:24am UTC](https://boards.straightdope.com/t/cell-phone-use-in-planes/64612/5 "2001-05-07T06:24:03Z")
OK, here’s a recap of the possible explanations offered: 1. Avoiding air rage. 2. Saving the cell phone companies hassles. 3. They don’t definitely know that they _won’t_ screw up the navigation equipment, so they ban them just in case. No. 3 is the only one that makes sense to me, because 1 and 2 don’t explain why they ban use of laptopa and other electronic devices too. I’m sorry if this has been answered before. I did a search like a good girl and couldn’t find it. ---
**Author:** ![Chas.E](https://avatars.discourse-cdn.com/v4/letter/c/e99b99/32.png) [@Chas.E](https://boards.straightdope.com/u/Chas.E)\ **Post date:** [May 7, 2001, 6:46am UTC](https://boards.straightdope.com/t/cell-phone-use-in-planes/64612/6 "2001-05-07T06:46:05Z")
They DON’T ban laptops on airplanes, they just require you to stow them during landing and takeoff. Just like all other carryon items. They DO ban the use of radio receivers, because they have no fixed frequency, and many models can radiate interference on an undeterminable frequency. Cel phones do not interfere with navigation equipment. If that were true, no airplane could fly anywhere near a cellular broadcast antenna. And of course they do it all the time. The main reason is because cel phones are a terrestrial system and if you are in the air, your signal can easily be received by several cels, where if you were on the ground, you’d only hit one. Broadcasting to several towers screws up the cellular system because it was never designed for that possibility. And of course, there is one last reason why cel phones are banned, to force people to use the expensive Sky-Phone. ---
**Author:** ![Daemon](https://avatars.discourse-cdn.com/v4/letter/d/c6cbf5/32.png) [@Daemon](https://boards.straightdope.com/u/Daemon)\ **Post date:** [May 7, 2001, 6:47am UTC](https://boards.straightdope.com/t/cell-phone-use-in-planes/64612/7 "2001-05-07T06:47:27Z")
> [@](#): > > \*Originally posted by Tatjana \* > \*\*OK, here’s a recap of the possible explanations offered: > > 1. Avoiding air rage. > 2. Saving the cell phone companies hassles. > 3. They don’t definitely know that they _won’t_ screw up the navigation equipment, so they ban them just in case. > > No. 3 is the only one that makes sense to me, because 1 and 2 don’t explain why they ban use of _laptopa_ and other electronic devices too. > > I’m sorry if this has been answered before. I did a search like a good girl and couldn’t find it. \*\* Ahhh… Laptopa… the lost and forbidden book of Gulliver’s Travels. You should see my copy sometime… ---
**Author:** ![Tatjana](https://avatars.discourse-cdn.com/v4/letter/t/d9b06d/32.png) [@Tatjana](https://boards.straightdope.com/u/Tatjana)\ **Post date:** [May 7, 2001, 6:55am UTC](https://boards.straightdope.com/t/cell-phone-use-in-planes/64612/8 "2001-05-07T06:55:45Z")
Chas, your explanation does not address other electronic devices, like CD players, that also have to be turned off during landing and take-off. I’m still finding Dr.Lao to be the most convincing. (Besides he’s a _doctor_.) I guess I really better watch my typos around here! ---
**Author:** ![Daemon](https://avatars.discourse-cdn.com/v4/letter/d/c6cbf5/32.png) [@Daemon](https://boards.straightdope.com/u/Daemon)\ **Post date:** [May 7, 2001, 6:59am UTC](https://boards.straightdope.com/t/cell-phone-use-in-planes/64612/9 "2001-05-07T06:59:58Z")
Prepare for the most enriching experience of your life… ---
**Author:** ![Chas.E](https://avatars.discourse-cdn.com/v4/letter/c/e99b99/32.png) [@Chas.E](https://boards.straightdope.com/u/Chas.E)\ **Post date:** [May 7, 2001, 7:20am UTC](https://boards.straightdope.com/t/cell-phone-use-in-planes/64612/10 "2001-05-07T07:20:48Z")
> [@](#): > > \*Originally posted by Tatjana \* > **Chas, your explanation does not address other electronic devices, like CD players, that also have to be turned off during landing and take-off.** Yes it does. You have to stow ALL items during takeoff and landing. You really don’t want to survive a crash, just to have the top of your head taken off by a flying CD player or laptop. Honestly, I was surprised that your seatmate could even GET a cel connection, until I read that you were on final approach. If you were any higher, she would have been in line-of-sight of several cels and she wouldn’t have gotten a connection. I once forgot to turn off my cel phone until we got to a high altitude, and I pulled it out to turn it off, and even though we were flying in an area that was covered by cellular, it showed that it could not make a connection. ---
**Author:** ![Tatjana](https://avatars.discourse-cdn.com/v4/letter/t/d9b06d/32.png) [@Tatjana](https://boards.straightdope.com/u/Tatjana)\ **Post date:** [May 7, 2001, 7:30am UTC](https://boards.straightdope.com/t/cell-phone-use-in-planes/64612/11 "2001-05-07T07:30:28Z")
I’m still not buying it, Chas. They don’t tell you that you have to _stow_ your electronic devices, they tell you that you have to _turn them off_. They do let you keep small items on your lap. Thanks, Daemon. I’ve got some big exams coming up and I won’t have much Internet access over the summer, so I don’t plan on becoming a regular. This board does seem more interesting than some of the ones I’ve taken to frequenting lately though. ---
**Author:** ![Broomstick](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/broomstick/32/246_2.png) [@Broomstick](https://boards.straightdope.com/u/Broomstick)\ **Post date:** [May 7, 2001, 9:57am UTC](https://boards.straightdope.com/t/cell-phone-use-in-planes/64612/12 "2001-05-07T09:57:04Z")
It’s an FCC regulation that bans cellphone use from the air, it has nothing to do with the airlines, FAA, or even the skyphone makers. The reason is that from the air cellphones will latch on to not just one but many towers, thereby monopolizing frequencies, screwing up billing, or just confusing the system to the point where something locks up. The reason they tell you to turn off all the other electronic goodies is two-fold: 1) it’s safer to stow objects so if you hit turbulence or, God forbid, a building or other large obstacle there is less flying debris to cause injury and/or clutter up your escape route from the burning wreck; and 2) there is a small but real _potential_ for the electronic toys/laptops/whatever to interfere with the airplane’s instrumentation. In other words, it really is for your safety. In small airplanes it’s up to the pilot to determine whether or not electronic goodies can be operated. I know of at least one private airplane owner who installed a nintendo in the back seat to keep the kids occupied instead of bothering daddy while he’s flying. But, in a small plane, it’s easy to flip a switch, figure out if there are any stray emissions causing a problem, then decide whether it’s OK to leave a gizmo running or not. And yes, it IS possible for an e-item to cause interference, although it is rare. It’s just not practical in a 747 to test every possible e-item in the passenger cabin so they just say “turn 'em ALL off” to be on the safe side. Why just landing then? Because that’s when the pilots need to be the most precise in what they’re doing, especially if the weather is anything but blue sky and sunny. ---
**Author:** ![Dr.Lao](https://avatars.discourse-cdn.com/v4/letter/d/2bfe46/32.png) [@Dr.Lao](https://boards.straightdope.com/u/Dr.Lao)\ **Post date:** [May 7, 2001, 2:33pm UTC](https://boards.straightdope.com/t/cell-phone-use-in-planes/64612/13 "2001-05-07T14:33:10Z")
> [@](#): > > \*Originally posted by Chas.E \* > **They DO ban the use of radio receivers, because they have no fixed frequency, and many models can radiate interference on an undeterminable frequency. > Cel phones do not interfere with navigation equipment. If that were true, no airplane could fly anywhere near a cellular broadcast antenna. And of course they do it all the time.** Isn’t this a contradiction? Cell phones are radio recievers and transmitters. ---
**Author:** ![Johnny\_L.A](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_l.a/32/1084_2.png) [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)\ **Post date:** [May 7, 2001, 3:16pm UTC](https://boards.straightdope.com/t/cell-phone-use-in-planes/64612/14 "2001-05-07T15:16:20Z")
The question has indeed come up before. [In this thread](http://boards.straightdope.com/sdmb/showthread.php?threadid=12807) I said **“The use of cell phones in flight is not prohibited by the FARs. It is an FCC regulation.”** and went on to portable electronic devices: > [@](#): > > Regarding portable electronic devices, see the FAA Advisory circular here: [http://www.bts.gov/NTL/DOCS/91-21\_1.html](http://www.bts.gov/NTL/DOCS/91-21_1.html) > > > [@](#): > > > > quote: > > Subject: USE OF PORTABLE ELECTRONIC DEVICES ABOARD AIRCRAFT > > > > 1. PURPOSE. This advisory circular (AC) provides aircraft assistance in the compliance of Federal Aviation Regulations (FAR) Section 91.21. Because of the potential for portable electronic devices to interfere with aircraft communications and navigation equipment, FAR Section 91.21 was established. It prohibits the operation of portable electronic devices aboard U.S.-registered civil aircraft, operated by the holder of an air carrier operating certificate or an operating certificate, or any other aircraft while operating under instrument flight rules. The rule permits use of specified portable electronic devices and other devices that the operator of the aircraft has determined will not cause interference with the safe operation of the aircraft in which it is operated. The recommendations contained herein are one means, but not the only means, of complying with the requirements of FAR Section 91.21, pertaining to the operation of portable electronic devices. The question was asked again just a month ago [here](http://boards.straightdope.com/sdmb/showthread.php?threadid=61875).