Anyone who has flown on an airplane should be familiar with the common pre-flight reminder to turn off cell phones on flight. For many people, this may seem silly or superfluous. What could your iPhone do that would possibly affect the flight? There are those who have left their phones on during flights and, having landed safely, are convinced that this Federal Aviation Administration (FAA) and the Federal Communication Commission (FCC) regulation is unnecessary. While neglecting to turn off your cell phone will not bring down the plane, there is a reason that flight crews require you to leave mobile phones off during our flights that goes beyond inconveniencing you.
Every electronic device emits radio waves, either by design or unintentionally. The waves emitted by electronic devices span most of the radio spectrum. The electronic systems used for navigation and communication on modern airplanes are known as avionics. Avionics rely heavily on radio waves, similar to those emitted from personal electronic devices, to connect to GPS satellites and to communicate with people on the ground. Theoretically, an electronic device, or a group of electronic devices, might be emit radio waves powerful enough to interfere with those associated with the plane’s avionics.
This raises a couple of questions: Why must passengers keep their phones off at all times while other devices can be used after take-off and landing? Is it possible for electronic devices, like pacemakers or hearing aids, to cause problems as well? As it turns out, the strength of the waves emitted from various devices is the most important factor in determining what can be used on an aircraft. Cellular phones emit relatively strong radio waves in order to reach cell towers and connect with other phones. On the other hand, a device like an MP3 player is not designed to send out radio waves and emissions are comparably much smaller. As for medical devices, thorough FAA testing has proven that pacemakers and hearing aids are safe for air travel.
Neither the FAA nor the FCC has found conclusive evidence that has directly linked cell phones with an airplane malfunction. However, there has been some anecdotal evidence of phone calls during flights causing fluctuations on a plane’s GPS. In December 2012, FCC Chairman Julius Genachowski endorsed the idea of lifting regulations on cell phone use. However, the FAA is not currently considering that option.
The only way to conclusively see which devices have an effect on the avionics, if any, would be to test each device individually. Due to the massive amount of cellular phones in the market and the rate at which new devices are introduced, it is not feasible to carry out these tests.
There is legitimate concern regarding whether or not cell phone signals can affect the avionics on commercial airplanes. There is a distinct possibility that you may not have to deal with this inconvenience in the future, but for now, make sure to power down your cell phone whenever you are flying.