Appliance Technology Blog

Appliance Technology

The Appliance Technology Blog is the place for conversation and discussion about Consumer Electronics; Medical Products; Home & Office Equipment; and Power Tools, Lawn and Garden. Here, you'll find everything from application ideas, to news and industry trends, to hot topics and cutting edge innovations.

Previous in Blog: Will You Buy a Smart Refrigerator?   Next in Blog: It’s Like an ATM for Old Cell Phones
Close
Close
Close
9 comments

Do Mobile Electronic Devices Really Interfere with Aircraft Communications?

Posted February 04, 2011 8:30 AM

The continuing quandary of turning off cell phones and other electronic devices during airliner take-offs and landings seems like it will never be resolved. Hmmm… let's think about that. If mobile electronics really did cause EMI with a plane's navigation system, wouldn't some tech specialist have to scan the entire plane's interior with a signal detector to make sure no one inadvertently left an offending device on? Or, should passengers bring their own detection device and scan for themselves. Perhaps an inexpensive detector — not unlike a Wi-Fi signal strength meter — could be used. What do you think?

The preceding article is a "sneak peek" from Appliance Technology, a newsletter from GlobalSpec. To stay up-to-date and informed on industry trends, products, and technologies, subscribe to Appliance Technology today.

Reply

Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Comments rated to be Good Answers:

These comments received enough positive ratings to make them "good answers".
Guru

Join Date: Oct 2010
Posts: 1294
Good Answers: 35
#1

Re: Do Mobile Electronic Devices Really Interfere with Aircraft Communications?

02/04/2011 10:12 AM

Wow--thank you! You cut right through all the BS--wish I had thought about that.

(I vaguely think I've seen other explanations for the ban, like minimizing noise / confusion / distraction to allow clear communication (from flight personnel to passengers) during a potential emergency.)

Reply Off Topic (Score 5)
Associate

Join Date: Jun 2009
Location: Tulsa, OK
Posts: 36
Good Answers: 1
#4
In reply to #1

Re: Do Mobile Electronic Devices Really Interfere with Aircraft Communications?

02/05/2011 10:36 AM

That my friend is the only reason (minimizing noise/confusion). I have been on many test flights where we used all sorts of elect. devices (before and after the iPod and cell phones). We used them prior to take off, during flight and landing (controlled crash). NOTHING happens. I never turn anything off. They just can't hear it. That is what they want.

__________________
Mike
Reply Off Topic (Score 4)
Guru
Technical Fields - Technical Writing - New Member Engineering Fields - Piping Design Engineering - New Member

Join Date: May 2009
Location: Richland, WA, USA
Posts: 21024
Good Answers: 790
#2

Re: Do Mobile Electronic Devices Really Interfere with Aircraft Communications?

02/04/2011 8:29 PM

This resembles the "Microwave in Use" signs that were common some years ago, but so far as I know turned out to be a nonissue.

Not to rule it out, but it seems unlikely that milliwatt signals at the radiation point (and probably microwatt by the time they encounter aircraft wiring) would have any notable effect on hard-wired watt or ten-watt control signals.

If there is an issue about cell-phone chatter interfering with aircraft communications, maybe some frequency reassignments would fix that?

__________________
In vino veritas; in cervisia carmen; in aqua E. coli.
Reply
Anonymous Poster
#3

Re: Do Mobile Electronic Devices Really Interfere with Aircraft Communications?

02/05/2011 4:19 AM

I just do not understand how this "switch off your mobile phone" business got started. The only danger that I can think of is that the signal from a mobile might be used to set of a bomb device. (which doesn't make sense as anybody coulkd still do that). So, that reason is a non starter. Perhaps the powers trhat be are just not telling the "oi poloi" (us the general public) the real reason for this procedure. Alternatively, perhaps some ignorant person of a safety committee suggested this and nobody since that event has ever challenged it. Thinking about it, using a mobile phone during take-off and landing can be a very distracting phenomenon for cabin crew personnel. So, the excuse that they give is very convenient for them. Otherwise, how can the cabin staff demand that you shut off your mobile device. Food for thought and how to control those nuisance passengers. Roger Cane

Reply
2
Commentator

Join Date: May 2010
Location: UK
Posts: 89
Good Answers: 2
#5

Re: Do Mobile Electronic Devices Really Interfere with Aircraft Communications?

02/05/2011 12:41 PM

the first type of cell phones.. non -digital did casue radio interference.. but never proved with aircraft avonics as they are shielded.

The INS, is NOT affected by radio waves as it work on a totally different system.

A friend who has worked for British Airways for many years was told by BA that due to Air Traffic Regulations.. ALL passengers must give their attention to the pre-flight safety brief, if using a phone... then who is paying attention??

Now the digital signal from the new phones cannot cause interference to Heart monitors in hospitals or any of the flying instruments in an aircraft. Further more there is no point in having the phone on after takeoff, as one flight attendant to me and the other passengers, once about 6000ft, you'll not get a signal anyway.. so save your battery.

All they want you as passengers to do is to sit back, relax, enjoy the flight and NOT annoy others with your mindless chatter on a phone.

Have you noticed how many flights DON'T have the on-board phones any more?

Reply Good Answer (Score 2)
Commentator

Join Date: Apr 2008
Posts: 59
Good Answers: 2
#6
In reply to #5

Re: Do Mobile Electronic Devices Really Interfere with Aircraft Communications?

02/06/2011 5:06 PM

If mobile phone signals could actually interfere with the navigation etc systems, it would be very easy for a terrorist to get a high-power directional antenna and sit 10 miles from a major airport and shoot each plane down as they arrived, with no trace whatsoever of their location.

The electrical interference issue may have been a problem in bygone years, but is a non-issue now. It is more about customer comfort. Have you ever tried to take a call in a crowded room? It's hard to hear yourself think. Now imagine 350 people in a small tin box, and half of them talking on the phone.... The loud guy to your left is making a great business deal with someone, the teenage girl to your right is gossiping with her friends, and like, OMG, like using like, the word like, like waaaay too much! It would be total chaos.

There have been proposals from some airlines (sorry, no reference, just something I remember, possibly and Australian airline) to allow data and SMS capabilities in-flight. As you say, at 13,000ft, you're just a bit out of range of the local towers (don't forget they use directional antennas so they don't waste energy pumping signals into space). The plane itself would need a local base station with a satellite uplink. I've seen a local base station to do a 2000 person building, it's about the size of a small home fridge. One to suit the range required for a plane would be much smaller, and easy to get onto a plane. This shows the electrical interference is a non-issue, but the comfort interference is an issue. You could easily check emails etc, and the teenage girls could SMS their mates, but it would still be a quiet flight.

As also mentioned previously, this would avoid people not paying full attention during safety briefings.

Reply
Power-User
United States - Member - New Member

Join Date: Aug 2008
Location: KY, USA
Posts: 367
Good Answers: 18
#7

Re: Do Mobile Electronic Devices Really Interfere with Aircraft Communications?

02/07/2011 11:51 AM

One possibility that apparently you have not considered is that not all commercial passenger planes are the same. Some of them are over 20 years old, and the test standards back then for EMF interference did not necessarily cover the exact signal range that your iPhone uses.

Possible technical issues aside, the most likely communication problem that would occur without this simple requirement would be that some jack-ass who is so consumed with himself that he refuses to take his eyes off of his phone for 2 seconds would fail to listen to instructions from the pilot and create an unnecessary delay for everyone on the plane.

__________________
The most valuable of all talents is that of never using two words when one will do. ~Thomas Jefferson
Reply
Guru
Popular Science - Weaponology - New Member Engineering Fields - Engineering Physics - New Member Engineering Fields - Nuclear Engineering - New Member

Join Date: Dec 2007
Location: No. VA, USA (No, it does NOTu mean "won't go"!)
Posts: 1793
Good Answers: 75
#8
In reply to #7

Re: Do Mobile Electronic Devices Really Interfere with Aircraft Communications?

02/07/2011 12:59 PM

I can easily buy the self-absorbed jackass (isn't that the same one who is carrying on the LOUD obnoxious conversation right next to me in an already over-crowded row of seats while I'm trying to read/sleep/eat lunch quietly), and that especially ties into the argument about just keeping it quiet, enjoying the flight and arriving rested, relaxed, and HAPPY FOR PETE'S SAKE!!

Now sit down, buckle in, shut up, and let me white-knuckle my way through this thing in peace? OK, YOU GOT IT?

And that kind of irritation is another reason the cabin crew would like to avoid the problems caused by the loud, obnoxious conversations of people who don't understand that the rest of us don't WANT to eavesdrop on their conversations, if they'd just have them quietly enough we didn't have to hear their garbage noise.

Besides, we want to listen to our own forms of garbage .. noise ... silence.

__________________
Been away a while. Miss all my old friends. Some of you I KNOW are still around. Where are the rest?
Reply
Anonymous Poster
#9
In reply to #7

Re: Do Mobile Electronic Devices Really Interfere with Aircraft Communications?

02/09/2011 11:24 AM

Good point ref.. aircraft over 20 years old, however as technology has changed then the upgrades have kept pace with the improving equipment, and it will always be cheaper to upgrade a older plane with new state of the art comms & Nav equipment than the scrap it and buy this years model.. which is what they do.

Aricraft frames can and do fly for many years, and all that does change is the inflight electronics.

The first 747 flight deck I paid a vist to (when you could), over 25 years ago, had a flight engineer in addition to the two pilots.

These days, its all computers, upgrades have done away with that third person... same aricraft, just upgraded.

with that upgrade would come the latest in shielding from interference, and if you have every flown at night, you will see the electric storms illuminating the sky, and sometimes hitting the aircraft..... does that aircraft suffer, does it mal-function, no it doesn't.

All due to the latest technology.

Thinking about it, you're safer flying than crossing the street!

thccontrols

Reply
Reply to Blog Entry 9 comments
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Comments rated to be Good Answers:

These comments received enough positive ratings to make them "good answers".
Copy to Clipboard

Users who posted comments:

Anonymous Poster (2); Critcho (1); EElectrician (1); memiles47 (1); micahd02 (1); rhkramer (1); thccontrols (1); Tornado (1)

Previous in Blog: Will You Buy a Smart Refrigerator?   Next in Blog: It’s Like an ATM for Old Cell Phones
You might be interested in: Focal Plane Arrays, Scan and Video Converters, Reticles

Advertisement