At these days of feeling as if naked at a deserted island when we don’t have our mobile phones with, it is for sure the most hated announcement of aircrafts hearing “Please turn your mobile phones off”. Like it or not we abide the  rule,but why is this measure necessary? Well, the answer to this question is right in it, this is a measure as most rough form..!

As I had shared in my previous articles, affecting other electronic devices with intentional or unintentional emissions from electronic devices is known as “Electromagnetic Interference” (EMI), where operating without causing or being affected from interference is known as “Electromagnetic Compatibility” (EMC). It is not difficult to find out that the main reason of the measure is this matter of fact..So, do the  mobile phones really cause harmful EMI? This question does not have clear and universally valid answer, it can be, or it is likely to be, because the matter depends on many factors; frequency of source, amplitude, environmental conditions, realization of the coupling requirements etc. All electronic devices of their nature, have electromagnetic emissions, more or less… It is unquestionably a fact that in case of this emissions build interference on the sensitive aircraft systems, it poses a vital risk!

Although the flight permissions are given after the aircraft passed the EMC tests and is certified to be in compliance with the standards, both as a system an also as equipment base, there is no guarantee that the test scenerio will exactly suit to the conditions of the real daily life! Think of it, notification of even a one percent margin of error is adequate for us to give up the use of the aircraft, taking the risk of this interference does not look very rational…

So, how big is the risk???

When using the mobile phone apart from its communication functions (as taking photo, playing music etc.) I can briefly state that the unintentional emissions are very small in amplitude. So the risk is “bigger than zero”, but clearly much too small. However, if the the subject is messaging or having a call, that requires wireless communication, we surely know that the intentional emissions of the device while trying to connect to the base station reach to high power levels, and also we know that those levels may be high enough to create risk to disturb the sensitive navigation systems of the aircraft. Although in today’s technology this risk is minimized with EMC precautions, it is still important  and can not be ignored…

Result; Stay away from mobile phones during flights! This will reduce the risk of danger, besides it also will lead to create an opportunity to socialize by contacting other passengers, face to face…