Posted on 06/03/2014 9:38:27 AM PDT by lowbridge
yeah—that does not convince me as i have read other info on other sites that say it is not unsafe... again, if it were, cell phones would not be allowed... the same way bombs are not allowed...
yes, i agree... but some insist they interfere... i am good friends with a couple of aviators, and related to one...
In the past 8 months, the FAA has changed their guidance. Most airlines are no longer requiring passengers to turn electronic devices completely off. How, they do ask you to put it in airplane mode.
Leaving the cell-phone enabled can interfere with both navigation and communication, as the frequencies are close, depending on harmonics. Depending on where you sit in the plane, you may be right over the antennas on the belly, or interfering with the cockpit audio system.
Plus, you are just running down your battery faster, as your phone boosts the transmitter to maximum power in an attempt to contact the cell phone tower on the ground (which can't hear it anyway).
Mythbusters didn't even begin to test all the possible ways a cell phone can interfere with aircraft avionics.
I have a pilot's license (instrument rating) AND an amateur radio license. There are very real technical reasons to turn off a cell-phone transmitter on an airplane.
bttt
Among every person I have read or heard claim it is not unsafe, not one of them is qualified to make that assessment.
The IEEE article that was provided to you is an authoritative source, written by people that have forgotten more about EMI (electromagnetic interference) than most people have ever learned. You shouldn't discount it so easily, unless you have similar credentials.
EMI from cell phones (and other transmitters) by itself isn't the problem. It's what happens after EMI occurs. Pilots are trained to recognize and compensate for avionics interference. We also have procedures for complete radio failure, and air traffic control knows what to expect if we use them.
Aviation safety is the result of layers: we have backups, and backups for backups. But, whenever you remove a layer, the margin of safety is reduced. And you run the real risk that interference distracts pilots from another problem that poses a real danger to the plane.
Gee, whom to believe the Institute of Electrical and Electronics Engineers’ radio frequency spectrum analysis or anonymous postings on an internet chat board? Tough call.
Yes, I always put it in airplane mode in the past for the reasons you mentioned. But it was never enough for them, so I just learned to hide it. I really hate rules that are created and enforced out of ignorance.
It's not ignorance. Rules about electronic devices were created by the FAA, based on sound technical reasons. Another poster provided a link to an IEEE article that explains the problem very well, although it may not be comprehensible to many people.
It should be noted that the FAA doesn't actually prohibit electronic devices. The rules makes the aircraft operator responsible for determining whether an electronic device interferes, and allowing the device only if they are sure it doesn't. So, in an abundance of caution, the aircraft operators required all devices not under their control to be turned off.
Electronic equipment installed on an airplane is carefully tested to be sure that it doesn't interfere with the avionics. The TSO standards (for aircraft) are much stricter than FCC type acceptance (for your cell phone).
All electronic devices (including your computer, even if it has no wireless capability) are required to have FCC Type acceptance. Do you know why? It's because your computer is transmitting all the time, just by being turned on. Any digital electronic device does this -- it's a law of physics. There's at least one oscillator in the device that generates a "clock" to drive the components of the device, like the microprocessor. The transmission is relatively weak, and the device can reduce transmissions with shielding, but it's impossible to completely eliminate them without putting the device in a metal box, with no holes for a headset, power, etc.
So what changed? There have been significant advances in electronic device design since the rules were first implemented in the 60's (or maybe earlier). Your phone, computer, etc. are better shielded. And aircraft avionics have better selectivity (a term describing a radio's ability to reject other signals). But again, there are laws of physics (and practical cost and weight issues) that prevent a radio from completely rejecting unwanted signals.
Maybe the flight attendant doesn't understand all the issues. But, he/she is required to enforce FAA rules, at the risk of discipline by their employer. And if her employer doesn't instruct her to enforce these rules, the airline can be fined or sanctioned by the FAA. So, if you have a problem with the rules, take it up with the FAA.
I’m talking about airplane mode.
Let’s be frank here. If the devices increased the risk the way some argue they do, they would be collected as you enter the plane, turned off, and returned to you when you deplane. The fact that they trust the passenger to turn off their device is proof that the risk is VERY low.
Yes, the risk is low. And, it is much lower than in the past, due to the advances I discussed in my previous posting.
But, as I explained in another posting earlier: even if the interference does occur (and there are multiple cases where it has been observed), it's not fatal. The airplane isn't going to crash.
Pilots are trained to recognize avionics problems, which can be caused by interference on the ground or in the plane, or outright failure on the ground or the plane. We have alternate procedures to compensate for it -- even a complete outage. Air traffic control will respond accordingly.
The real risk is that the problem isn't recognized, and it leads to a conflict that wouldn't have occurred otherwise. Or worse, the problem causes a distraction, which results in a dangerous situation.
The fact that they trust the passenger to turn off their device is proof that the risk is VERY low.
I've had this rock for my entire life. I carry it in my pocket to scare off tigers. I've never been attacked by a tiger, so it must work. Right?
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