Why do we have to switch our cellphones off on a plane?

South Africa
July 16, 2011 12:42pm CST
This is something that I have always wondered, and as I was flying today I asked myself again - why on earth do we have to switch our cell phones off on a plane? I forgot to bring a book to read on my flight and was in the middle of some sudoku on my phone - I wish that we were allowed to use phones during the flight, just to play games even! I always thought that the phones interfered with the signals during the flight, but I was told the other day that that wasn't true - so then why do we have to switch them off? Has anyone ever wondered this before? And does anyone know the answer??
2 people like this
7 responses
• Philippines
17 Jul 11
Here's a simple experiment on how to justify the fact that cellphone signals indeed can interfere with other electronic signals. Put your cellphone beside the television set or FM radio receiver. Try to call or send an sms message. You will observe that the incoming signals going to your cellphone were received also by the television or the FM receiver. Due to difference in frequency, the TV receiver cannot decode those signal thus you can hear an annoying sounds on the speakers. The same principle goes with the plane. Airplane uses electronic devices to communicate with the airport towers or to other nearby airplanes during take off and landing. Interference to their communications might result to accident. So the next time you travel, don't forget to bring your book or just take a nap.
• South Africa
17 Jul 11
Yes, you're absolutely right about how cellphones interfere with TV signals, radios and even with analog telephones - you always get that annoying sound when you are about to receive a message. Its interesting that a plane, which must have the most sophisticated receiving devices for electrical signals, can still get thwarted by a cellphone! But of course would not want to jeopardise a flight so I would never keep my cellphone on - for my own safety and those around me!!
1 person likes this
• United States
16 Jul 11
Although I too find this annoying, I try to see the positiveness of it; gives me a chance to read on a plane or just do something to completely relax. Remember the days before cell phones and what we did?
• South Africa
17 Jul 11
Haha yes I guess you're right - sometimes it is quite nice to have a good excuse to not be contactable!!
• United States
17 Jul 11
Very true! As I often miss my reading time, I use it to read while on a plane. What do you do?
• United States
18 Jul 11
Yes, I wondered and my answer what the same as yours. But now that you say the cell doesn't interfere with the signal I am eager to know why we have to turn them off then. Maybe its because when they are talking to us on the plane we won't pay attention. I don't know. I am way curious now.
• United States
18 Jul 11
Oh okay, I just read the thread. Now I have a better idea of why and how this works. Very interesting. Let's not interfere with the flight though, lol...I already have to talk to myself when I fly, LMBO!
@maximax8 (27048)
17 Jul 11
Right now I have got my third mobile phone. My first mobile phone broke and my second mobile phone I lost. That second mobile phone had a flight safe mode on it yet I still wasn't allowed to use it on my plane trips. I wonder if so mobile phones do affect something to so with the plane. It would be challenging to make sure all passengers were using the safe mode setting. Flight rules are strict it seems to me. Yes, some mobile phones have games on which would be lovely to use inflight.
• South Africa
18 Jul 11
I always wonder what the purpose is of phones having a flight mode function if no one is ever allowed to use them, even in flight mode, on a flight! Also another interesting thought - if you are flying in a small, private, non-commercial plane, like a 4 seater plane or something, can you use a cell phone then?
@JoyfulOne (6243)
• United States
17 Jul 11
They just had a news program devoted to that very question (about a week ago.) It seems that the signals interfere with some of the planes different electronics, and important instructions from the control tower are often missed. By missed I mean that there are skips and jumps in the transmission. Now, if I was on a plane, I would want that pilot and control tower to have reliable communication at all times. It was an interesting program, and very eye opening, to say the least. In view of the fact that it's potentially putting a whole aircraft in danger, as well as the lives of all those people on board, I think it only makes sense to shut them off when asked. Besides, there are always books, hand-held games, crossword puzzles, or other things that can be used to entertain ourselves.
• South Africa
17 Jul 11
You're right - there are certainly other things to keep ourselves busy so I must just remember to bring them with me next time! That is interesting that there was a whole television programme on it - obviously other people were wondering the same thing as me, and I am glad to see that some research has been done into proving conclusively that it does in fact interfere with the signals! Thanks for this info.
• India
16 Jul 11
The usage of cellphones during flights is very harmful and can cause damage by interfearing with the aircrafts communication system and navigation systems. Cellphones send out signals to satellites to attain a signal. When you flying some 35000feet above you do not get a signal and at this time the cellphone will try its best to catch hold of some available network. At the same time the aircrafts navigational system is also constantly sending signals to the ground of its movement above. So this could act as a hazard and disrupt a smooth flight and confuse captains. It could also cause a threat to the people travelling in that plane. With so much of sofisticated technology in an aircraft, the use of electronic devices serves as a severe threat..
• South Africa
17 Jul 11
Thanks for your response! This is very interesting and all these responses are helping me to answer something that has been bugging me for AGES! Isn't that the great thing about MyLot? I understand now why they have to tell you to switch them off - I guess maybe one or 2 cellphones wouldn't make much a difference, but if EVERYONE in the plane is frantically trying to find signal and sending signals in every direction, I can see how this would interfere with the plane's signals!
@KrauseHome (34153)
• United States
17 Aug 11
Personally I think it is something to do with a Safety issue, even though I have seen people using theirs later in the flight. I know that people are allowed to use Laptops etc. so maybe this is a something to do with Security or privacy? Personally would be interesting to know wouldn't it?