Airplane mode is a setting on many cellphones which disables their wireless communication abilities, theoretically making them approved for use on aircraft. While in airplane mode, a phone cannot send or receive phone calls, text messages, picture messages, or video messages. However, functions like music players, games, calendars, and so forth can continue to be used.
The idea behind airplane mode is that many people wish to continue using their cell phones on planes to do things like listen to music and check appointments, but the use of cell phones on planes is banned due to the fact that their signals could cause interference. Airplane mode allows cell phone users to circumvent the ban, ensuring that their phones are safe to use on aircraft while the plane is in flight; electronic devices must be turned off for takeoff and landing.
There are two reasons why people are not allowed to use cell phones on aircraft, although the rules against cell phone usage may change at some point. The first reason is that the radio signals emitted by phones could interfere with the communications and guidance systems on the aircraft, which could potentially be very dangerous. In addition, cell phone networks on the ground cannot cope with cell phones being used on planes, because planes travel very fast and at high altitude, so a phone on a plane could confuse a network on the ground.
If a phone offers an airplane mode setting, the user's manual usually clearly shows how to turn airplane mode off and on, and typically it can also be found through the phone's menu. When airplane mode is activated, a small icon often shows up on the screen of the phone to indicate this. In some cases, the user may have to use a password to activate and turn off airplane mode, to ensure that it is not accidentally switched on and off.
Although airplane mode technically makes a phone legal to use on an aircraft, some airlines request that passengers turn their cellphones off anyway, or a flight attendant who is not familiar with the technology may ask you to turn your phone off. Sometimes, explaining that you are using airplane mode is sufficient, and the flight attendant will allow you to leave your phone on, but in other cases, you may be asked to turn it off. Although this may seem unreasonable, it is better to comply; in the wake of the 11 September 2001 terrorist attacks in the United States, airlines are entitled to remove passengers from flights if they fail to comply with requests the airline terms “reasonable.”