I was recently positioning and had my iPad switched on because I was reading a book as we were taxying out towards the runway. The lights were dimmed, and I was just relaxing and getting into the book when I heard an annoyed lady exclaim “switch you computer off!”. It did startle me a bit and so I turned to my left to see an annoyed expression on the passenger who had instructed me to put my iPad away. I politely explained to her that we are now allowed to use these portable devices as long as they are in airplane mode and I pointed to the airplane symbol on the top corner of my iPad. It didn’t seem to satisfy her and she sharply turned her gaze away.
“Surely these multi-million dollar airplanes can handle any interference from these relatively cheap devices?”
So, why do we need to switch off electronic devices or at least put them on airplane mode? Surely these multi-million dollar airplanes can handle any interference from these relatively cheap devices? I always get asked this question from baffled passengers, friends and family members. I can think of two reasons to why we are asked to switch these devices off. One reason is that there is the potential for interference with the aircraft systems, and the other is so that passengers can pay attention to the safety demonstration and be alert of their surroundings during critical phases of flight (take off and landing)! I always find it disrespectful when I see passengers ignoring the pleas of cabin crew to switch off electronic devices and generally ignoring the safety demonstration. I am sure many people may have seen the safety demonstration repeatedly if they are frequent fliers, nonetheless, a refresher that will take only couple of minutes is always good!
In the case of interference, though there’s been no clear scientific study, there is anecdotal evidence that points to electronic devices being the culprit. There was a discovery made recently during testing of an onboard wifi system, which showed that wifi signals interfered with display screens in the flight deck, causing them to blank for up to 6 minutes. This is quite critical because the display screens give pilots vital information such as the airspeed, altitude and the attitude of the aircraft. This can be especially dangerous during take off or landing, if it were to occur. The FAA has mandated a fix to the systems to avoid this though.
The FAA has since 2013 allowed the use of portable electronic devices (PEDs) – at least in airplane mode. Similarly, on the other side of the Atlantic, the European Aviation Safety Agency (EASA), has approved the use of PEDs in all stages of flight. Initially, after a safety assessment process, EASA allowed the use of PEDs in airplane mode during any stage of flight in December 2013. Then from 26 September 2014, EASA permitted the use of PEDs whether in airplane mode or not (so they can transmit) during any stage of flight. Though EASA permits this, each airline can make the rules more restrictive, so airlines can still enforce electronic devices to be switched off. This is generally the case worldwide – the regulator such as EASA makes the rules, however operators (e.g. airlines) can be more restrictive. Ryanair currently allows small PEDs to be switched on during all stages of flight, but must still be in airplane mode (to ensure there’s no transmission).