Yes, but there would be no need to turn the thing off in that case; you would merely put it to sleep, and that is not the instruction.
The cell phone story is indicative of a slightly different concern than what we have been discussing. The original intent of turning off electronics was, as has been mentioned before, avoiding radio frequency interference (rfi), that is, interference to broadcast radio reception, either communications or navigation-related. The multiple cell phone experiment seems to address another issue, that of interference to non-antenna-connected equipment. The reason for saying that is that the attempt seems to be to generate a field intensity of many Volts per meter, over a wide area, which is what would be necessary to (theoretically) cause interference to equipment with much higher thresholds of susceptibility than radios have. One might imagine that with enough rf signal, and the right modulations, an intercom or other low-level audio link might be corrupted. The impact of that would vary according as to whether it was interruption of an entertainment system, or whether it compromised communications amongst the cabin and/or flight crews. Ken Javor Phone: (256) 650-5261 > From: "Gartman, Richard" <[email protected]> > Date: Thu, 24 Sep 2009 09:32:52 -0500 > To: Ken Javor <[email protected]>, "[email protected]" > <[email protected]> > Conversation: Article on "portable electronics" aboard airplanes > Subject: RE: Article on "portable electronics" aboard airplanes > > The best reason I have heard from a flight attendant (this happened only once) > for putting the computer away was " do you want a 5 pound projectile flying > around the cabin if there is an incident". You cannot argue with that logic. > > Does any on have the report of the KLM/FCC cell phone test that was done in > Phoenix several years back. As I hear the story, a KLM "Boeing" aircraft was > filled with cell phones (one in each seat) and they all went active at the > same time. The intent was to see if a plane loaded with cell phones could > cause interruption to the aircrafts electronics. > > I am sure this group would enjoy that report. > > Have a great day > W. Richard Gartman, MS, CSP > > -----Original Message----- > From: [email protected] [mailto:[email protected]] On Behalf Of Ken Javor > Sent: Thursday, September 24, 2009 9:18 AM > To: [email protected] > Subject: Re: Article on "portable electronics" aboard airplanes > > While having stuff put away during take-off and landing makes sense, just as > you say, protection of aircraft radio and navigation receivers is the > primary driver. Paralleling control of rfi on the ground, the first such > rfi control only applied to radios, because of local oscillators, and then > later applied to digital electronics, because the clocks and their harmonics > could radiate just like the radio's LO could. > > Ken Javor > > Phone: (256) 650-5261 > > >> From: Nick Williams <[email protected]> >> Date: Thu, 24 Sep 2009 15:02:55 +0100 >> To: Ken Wyatt <[email protected]> >> Cc: <[email protected]> >> Subject: Re: Article on "portable electronics" aboard airplanes >> >> I've always understood that, certainly so far as commercial airliners >> are concerned, EMC was never really the issue. Far more to the point >> is the fact that take off and landing are statistically the most >> likely time for there to be an emergency which requires the >> passengers to be paying attention to what the cabin attendants have >> to say rather than listening to or fiddling with their personal >> possessions. >> >> It also can't do any harm for the cabin not to be cluttered up with >> laptops and other junk for people to trip over if you need to get >> everyone off in a hurry. >> >> Nick. >> >> >> >> At 22:26 -0600 23/9/09, Ken Wyatt wrote: >>> I thought I'd post this link to a semi-rant by one of the Gizmodo >>> editors on the use of electronics aboard aircraft. He brings up some >>> good points regarding the EMI properties of various gadgets. It's >>> also interesting how he and other non-EMCers think on the whole >>> subject. >>> >>> Has anyone on this list studied the emissions characteristics ("on" >>> versus sleep mode) for various portable electronic products? >>> >>> I'd love to not be hassled when using my Bose headphones. >>> >>> http://gizmodo.com/5366128/giz-explains-how-to-fix-the-airlines-stupid-porta>>> b >>> le-gadget-rules >>> >>> Regards, Ken >>> ---------------------------------------------- >>> Wyatt Technical Services, LLC >>> 56 Aspen Dr. >>> Woodland Park, CO 80863 >>> >> >> - >> ---------------------------------------------------------------- >> This message is from the IEEE Product Safety Engineering Society emc-pstc >> discussion list. To post a message to the list, send your e-mail to >> <[email protected]> >> >> All emc-pstc postings are archived and searchable on the web at: >> http://www.ieeecommunities.org/emc-pstc >> Graphics (in well-used formats), large files, etc. can be posted to that URL. >> >> Website: http://www.ieee-pses.org/ >> Instructions: http://listserv.ieee.org/request/user-guide.html >> List rules: http://www.ieee-pses.org/listrules.html >> >> For help, send mail to the list administrators: >> Scott Douglas <[email protected]> >> Mike Cantwell <[email protected]> >> >> For policy questions, send mail to: >> Jim Bacher: <[email protected]> >> David Heald: <[email protected]> > > - > ---------------------------------------------------------------- > This message is from the IEEE Product Safety Engineering Society emc-pstc > discussion list. To post a message to the list, send your e-mail to > <[email protected]> > > All emc-pstc postings are archived and searchable on the web at: > http://www.ieeecommunities.org/emc-pstc > Graphics (in well-used formats), large files, etc. can be posted to that URL. > > Website: http://www.ieee-pses.org/ > Instructions: http://listserv.ieee.org/request/user-guide.html > List rules: http://www.ieee-pses.org/listrules.html > > For help, send mail to the list administrators: > Scott Douglas <[email protected]> > Mike Cantwell <[email protected]> > > For policy questions, send mail to: > Jim Bacher: <[email protected]> > David Heald: <[email protected]> > - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
