[FoRK] Disruptions: Fliers Must Turn Off Devices, but It's Not Clear Why

Stephen Williams sdw at lig.net
Tue Dec 6 10:01:17 PST 2011

On 12/6/11 9:22 AM, Gary Stock wrote:
> On 12/6/11 11:36 AM, Sean Conner wrote:
>> The issue not be with avionic interference, but actual cellular networkissues. 
> Yes.  Thank you.  While I despair of security theater generally, other legitimate issues are being ignored during the pile-on 
> drubbing of the phones-off policy.

That was one legitimate concern.  But it only applies during takeoff and landing when the plane is actually in range of towers.  
Anything over 3000 ft. or so and the signal won't reach, especially from inside an aluminum can with tiny portholes.  And the 
government and airlines chooses to thinly lie about the reason, I guess because someone came to the conclusion that people 
wouldn't care about the real reason.  So, they dress it up as security and then, more or less illegally since it is a lie, give 
it the force of Federal law for enforcement.  Government mendacity is abhorrent, even here.

While passengers have little effective security responsibility other than staying seated, it's not a bad idea to turn off 
broadcasting electronics (but not e-ink ebooks and similar) during the 10 minute zone around takeoff/landing. In between, above 
5K, it's just silly.

And, no longer the case since Wifi is now sold broadly and cellular-compatible radio is about to come on line (but for 
text/Internet rather than voice, only for social reasons).

> At normal commercial cruising altitudes, no cell phone gets a signal.  (Yes, I've verified it.  Between Detroit and 
> Baltimore.  Multiple times.  So arrest me. ;-)
> What are people whining about?  The fact that they might be unable to use a device in a venue where -- by ~design~ -- it 
> ~will~ not work?

Until the airlines can sell it to you.  Then suddenly the security threat evaporates back to the actual nearly non-existent 
level of reality.

> (Even if cell towers were four or five miles tall, ~most~ long flights also spend ~most~ of their time over vast expanses of 
> land that have little or no coverage even on the ~ground~.)
> This thread has already mentioned the possibility of intentional electronic exploit (or a takeover of some sort, even of 
> communications) from within the plane, while in midair.  Acknowledging that terrorists -- by definition -- will ignore rules 
> and laws, which flight would you rather take:
> 1) with 100+ cellphones, and similar devices obviously in use?
> 2) with only a terrorist's electronic device obviously in use?

Filtering for frequency is the most basic sigint.  There could be a thousand radios at 2.4Ghz and an AM aviation frequency will 
still stand out.  And such a radio is not illegal.  I have often carried my hand-held aviation transmitter when I thought I 
might want to fly at an endpoint.

> OK, you say, what if they put it in cargo, or luggage -- or hide it under a blanket?
> OK, let's presume they do.  Presume we suspect a credible threat may exist of such a device eventually (or at a particular 
> time or location) being deployed on a commercial flight, or in its immediate environment.
> Thinking as we did at NSA:  our challenge is to recognize, understand, and defeat such a device.  We have only some notion of 
> what forms it may take, or frequencies it may use.
> Q:  What would be our first priority?
> A:  Isolate and rule out effects from all other devices.
> Q:  What is the easiest way to do that?
> A:  Shut as many such devices as possible off.
> Q:  How can we do that without alerting terrorists to our effort?
> A:  Shut as many such devices as possible off ~ALL~ the time.
> Crude But Effective(tm).

What's possible is much broader than what is probable, and we generally don't lock everything down for the most extreme case.  
The fact that powerful, noisy communication is allowed when the airlines can make money on it undermines the whole argument.

> I'd submit that most of the research validating why the ban ~may~ be valid is highly classified -- just like most of the work, 
> likely ongoing today, that will eventually make the ban unnecessary.
> GS 


More information about the FoRK mailing list